Abstract:
A charging control apparatus is adapted to control an alternator which is operable to generate a voltage to charge a battery which is operable to supply the voltage to an electric component. An interface is connected to the alternator, the battery, and the electric component and operable to input and output a signal therebetween. A microcomputer is connected to the inter face and operable to execute a gradual change process in which a generating voltage of the alternator is gradually changed to a target generating voltage of the alternator and a sudden change process in which the generating voltage is suddenly changed to the target generating voltage. The microcomputer is operable to detect a using status of the electric component based on the signal. The microcomputer is operable to judge whether the gradual change process is required or the sudden change process is required based on the detected using status. The microcomputer executes the sudden change process when the microcomputer judges that the sudden change process is required. The microcomputer executes the gradual change process when the microcomputer judges that the gradual change process is required.

Description:
The disclosure of Japanese Patent Application No. 2006-042578 and No. 2006-042579 both filed Feb. 20, 2006 including specifications, drawings and claims are incorporated herein by reference in its entireties. 
   BACKGROUND 
   The present invention relates to a charging control apparatus and a charging control method. 
   A battery for supplying power to electric components and an alternator for generating the power to charge the battery while an engine is operated are mounted on an engine-driven vehicle. 
   In a related-art charging control, as one of methods for rapidly charging the battery, an alternator adjustment voltage to adjust a voltage generated by the alternator is set to relatively high voltage when the vehicle is decelerated since the alternator can generate much power by regeneration thereof, thereby increasing the power generated by the alternator. In addition, the alternator adjustment voltage is set to relatively low voltage when the vehicle is accelerated since engine torque required for accelerating the vehicle is prioritized, thereby decreasing the power generated by the alternator. 
   While such a charging control, if the alternator adjustment voltage is suddenly changed from a high value to a low value and vice versa, a voltage of the battery connected to the alternator is also suddenly changed. The suddenly changing of the voltage of the battery may effect operation of the electric component mounted on the vehicle. For example, a light mounted on the vehicle suddenly flickers. 
   In order to prevent the voltage of the battery from being suddenly changed, in the related-art charging control, the alternator adjustment voltage is gradually changed to a target alternator adjustment voltage (see Japanese Patent No. 3044867, paragraphs [0017] to [0022]). 
   However, in the related-art charging control, for example, even in a case where the light is not used, the alternator adjustment voltage is gradually changed when the vehicle is decelerated or accelerated, so that charging efficiency of the battery is decreased. 
   On the other hand, with sudden spread of vehicles, needs for improving comportability, safety, and convenience of vehicles are increased. To satisfy the needs, the number of the electric components such as an air conditioner and a navigator which are installed in the vehicle is increased, thereby increasing electrical load of the battery. Therefore, it is necessary to control for charging the battery in order to prevent the battery from voltage reduction and deterioration. 
   However, in some cases, the charging efficiency of the battery is deteriorated according to condition of the battery. In order to overcome such a problem, in a related-art battery charging apparatus, the charging efficiency of the battery is determined from an open voltage of the battery and a regulator adjustment voltage to indirectly control a voltage output from the alternator is corrected based on the determined efficiency of the battery (see Japanese Patent No. 3010719). Namely, the related-art battery charging apparatus prevents the battery from an overcharging by correcting the regulator adjustment voltage according to the charging efficiency of the battery, thereby increasing the lifetime of the battery. 
   However, although the related-art battery charging apparatus controls the alternator to charge the battery according to the charging efficiency of the battery in order to improve the lifetime of the battery, it does not control the alternator in order to rapidly charge the battery. 
   SUMMARY 
   It is therefore an object of the invention to provide a charging control apparatus and a charging control method, which are capable of charging a battery with high efficiency. 
   It is also an object of the invention to provide a charging control apparatus which is capable of rapidly charging a battery by correcting a target electric quantity to be output from an electric generator such as an alternator based on a condition of a vehicle. 
   In order to achieve the above described objects, according to the invention, there is provided a charging control apparatus adapted to control an alternator which is operable to generate a voltage to charge a battery which is operable to supply the voltage to an electric component, the charging control apparatus comprising: 
   an interface, connected to the alternator, the battery, and the electric component and operable to input and output a signal therebetween; and 
   a microcomputer, connected to the inter face and operable to execute a gradual change process in which a generating voltage of the alternator is gradually changed to a target generating voltage of the alternator and a sudden change process in which the generating voltage is suddenly changed to the target generating voltage, wherein: 
   the microcomputer is operable to detect a using status of the electric component based on the signal; 
   the microcomputer is operable to judge whether the gradual change process is required or the sudden change process is required based on the detected using status; 
   the microcomputer executes the sudden change process when the microcomputer judges that the sudden change process is required; and 
   the microcomputer executes the gradual change process when the microcomputer judges that the gradual change process is required. 
   According to the invention, there is also provided a charging control method for controlling an alternator which is operable to generate a power to charge a battery which is operable to supply the power to an electric component, the charging control method comprising: 
   detecting a using status of the electric component; 
   judging whether the gradual change process in which a generating voltage of the alternator is gradually changed to a target generating voltage of the alternator is required or sudden change process in which the generating voltage is suddenly changed to the target generating voltage based on the detected using status; 
   executing a sudden change process when the sudden change process is required; and 
   executing the gradual change process when the gradual change process is required. 
   According to the charging control apparatus and the charging control method, since it is determined whether the gradual change process is required or the sudden change process is required, based on the using status of the electric component, the gradual change process can be executed only when the electric component is used. 
   Accordingly, when the electric component is used, since the gradual change process is performed to gradually change the generating voltage of the alternator to the target generating voltage of the alternator, the voltage of the battery is prevented from being suddenly changed. Therefore, the operation of the electric component is not effected by the changing of the voltage of the battery. In addition, when the electric component is not used, since the sudden change process is performed to suddenly change the generating voltage of the alternator to the target generating voltage of the alternator, the charging efficiency of the battery is improved, whereby the battery is rapidly charged. 
   According to the invention, there is also provided a charging control apparatus adapted to control an alternator which is operable to output an electric quantity to charge a battery mounted on a vehicle, the charging control apparatus comprising: 
   a detecting section operable to detect a condition of the vehicle; 
   a determining section operable to determine a target electric quantity of the alternator; 
   a correcting section operable to correct the target electric quantity based on the detected condition. 
   With this configuration, since the target electric quantity is corrected based on a correction value suitable for the conditions of the vehicle, the battery can be rapidly charged. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein: 
       FIG. 1  is a schematic diagram showing a charging control system according to a first embodiment of the present invention; 
       FIG. 2  is a schematic diagram showing a hardware configuration of a charging control apparatus according to the first embodiment; 
       FIG. 3  is a schematic diagram showing a functional configuration of the charging control apparatus; 
       FIG. 4  is a flow chart showing a gradual change requirement determination process according to the first embodiment; 
       FIG. 5  is a flow chart showing a first former gradual change requirement determination process according to the first embodiment; 
       FIG. 6  is a flow chart showing a second former gradual change requirement determination process according to the first embodiment; 
       FIG. 7  is a flow chart showing a first latter gradual change requirement determination process at a first latter stage according to the first embodiment; 
       FIG. 8  is a diagram showing a relationship between a battery voltage and a charging rate according to the first embodiment according to the first embodiment; 
       FIG. 9  is a diagram showing a relationship between liquid temperature and a correction coefficient of a charging rate according to the first embodiment; 
       FIG. 10  is a flow chart showing a second latter gradual change requirement determination process according to the first embodiment; 
       FIG. 11  is a flow chart showing a third latter gradual change requirement determination process according to the first embodiment; 
       FIG. 12  is a flow chart showing a fourth latter gradual change requirement determination process according to the first embodiment; 
       FIG. 13  is a flow chart showing a gradual change rate decision process according to the first embodiment; 
       FIG. 14  is a diagram showing a first gradual change rate table according to the first embodiment; 
       FIG. 15  is a diagram showing a second gradual change rate table according to the first embodiment; 
       FIG. 16  is a diagram showing a sudden change process according to the first embodiment; 
       FIG. 17  is a diagram showing a gradual change process according to the first embodiment; 
       FIG. 18  is a schematic diagram according to a second embodiment of the invention; 
       FIG. 19  is a schematic diagram showing a charging control system according to a second embodiment of the present invention; 
       FIG. 20  is a schematic diagram showing a hardware configuration of the charging control apparatus according to the second embodiment; 
       FIG. 21  is a schematic diagram showing functional configuration of the charging control apparatus; 
       FIG. 22  is a diagram showing a relationship between an open voltage of a battery and a battery charging rate according to the second embodiment; 
       FIG. 23  is a diagram showing a relationship between a liquid temperature and a correction value of a battery charging rate according to the second embodiment; 
       FIG. 24  is a diagram showing a relationship between a battery charging rate and a correction value of a voltage according to the second embodiment; 
       FIG. 25  is a diagram showing a relationship between a liquid temperature and a correction value of a voltage according to the second embodiment; 
       FIG. 26  is a diagram showing a relationship between a consumption current of an electric component and a correction value of a voltage according to the second embodiment; 
       FIG. 27  is a diagram showing a relationship between a battery charging rate and a time to determine whether or not a correction process is performed again according to the second embodiment; 
       FIG. 28  is a diagram showing a relationship between a battery charging rate and a time to interrupt a voltage correction process according to the second embodiment; 
       FIG. 29  is a diagram showing a relationship between remaining fuel and a time to stop a voltage correction process according to the second embodiment; 
       FIG. 30  is a diagram showing a data structure of a charging rate-correction value table according to the second embodiment; 
       FIG. 31  is a diagram showing a data structure of a vehicle condition-correction value table according to the second embodiment; and 
       FIG. 32  is a flow chart showing a process of battery charging control according to the second embodiment. 
   

   DETAILED DESCRIPTION OF THE EMBODIMENTS 
   Hereinafter, a first embodiment of a charging control apparatus and a charging control method will be described in detail with reference to the accompanying drawings. 
   Firstly, a system configuration of a charging control system will be described. 
   As shown in  FIG. 1 , a charging control system includes a charging control apparatus  10  for controlling charging of a battery  11 . An alternator  12  for generating power while an engine is operated so as to charge the battery  11 , electric components  13 , and the battery  11  for supplying power to the electric components  13  are connected to the charging control apparatus  10  via a power line  14 . 
   The battery  11  is provided with a voltage sensor  15  for detecting a voltage of the battery  11 , a current sensor  16  for detecting current of the battery  11 , and a temperature sensor  17  for detecting liquid temperature of the battery  11 . The voltage sensor  14 , the current sensor  16  and the temperature sensor  17  are connected to the charging control apparatus  10  via a signal line  18 . In addition, the alternator  12  is provided with a voltage sensor  19  and a current sensor  20 . The voltage sensor  19  and the current sensor  20  are connected to the charging control apparatus  10  via the signal line  18 . 
   In addition, the charging control apparatus is connected to a car navigator  21  for acquiring information on a position of the vehicle and driving path of the vehicle, and a radio  22  for acquiring weather information and so on. 
   For example, the electric components  13  are a light and a wiper. Namely, using status of the electric components  13  can be visually and/or auditorily recognized by a user. 
   Based on signals from the voltage sensor  15 , current sensor  16  and temperature sensor  17  of the battery  11 , signals from the voltage sensor  18  and current sensor  20  of the alternator  12 , and signals from the car navigator  21  and the radio  22 , the charging control apparatus determines whether it is required or not to perform a gradual change process in which a generating voltage of the alternator  12  is gradually changed to a target generating voltage of the alternator  12 , and controls the charging of the battery  11  based on a result of the determination. Here, the generating voltage of the alternator  12  represents a voltage currently generated by the alternator  12 . And the target generating voltage of the alternator  12  represents a voltage to be generated by the alternator  12 . 
   Next, a hardware configuration of the charging control apparatus  10  will be described. 
   As shown in  FIG. 2 , the charging control apparatus  10  comprises a microcomputer  30 . The microcomputer  30  is connected to a bus  31  in the charging control apparatus  10  and is connected to the signal line  18  via an I/F (interface)  32 . 
   The microcomputer  30  comprises a CPU (Central Processing Unit)  34 . The CPU  34  is connected to a ROM (Read Only Memory)  35  and a RAM (Random Access Memory)  36  via a bus  37  in the microcomputer  30 . In addition, the CPU  34  is connected to the bus  31  via the bus  37 . 
   The CPU  34  controls a whole operation of the charging control apparatus  10 . A program of an OS (Operating System) or at least a portion of an application program to be executed by the CPU  34  is temporarily stored in the RAM  36 . In addition, various kinds of data required for processes by the CPU  34  are stored in the RAM  36 . An OS and application programs are stored in the ROM  35 . 
   The stored application programs include programs for a gradual change requirement determination process, a gradual change rate decision process, a sudden change process and a gradual change process, which are performed by the charging control apparatus  10 . 
   Next, a functional configuration of the charging control apparatus  10  which is embodied by the hardware configuration of  FIG. 2  will be described. 
   As shown in  FIG. 3 , the charging control apparatus  10  comprises a battery condition detecting section  41 , an alternator condition detecting section  42 , a using status detecting section  43 , a vehicle running condition detecting section  44 , an using status predicting section  45 , a vehicle running condition predicting section  46 , a gradual change requirement determining section  47 , a gradual change rate deciding section  48 , a sudden change performing section  49  and a gradual change performing section  50 . 
   The battery condition detecting section  41  detects condition of the battery  11  by detecting a voltage, current and liquid temperature of the battery  11 , which are detected by the voltage sensor  15 , the current sensor  16  and the temperature sensor  17 , respectively. In addition, the alternator condition detecting section  42  detects condition of the alternator  12  by detecting a voltage and current to be generated by the alternator  12 , which are detected by the voltage sensor  19  and the current sensor  20 , respectively. 
   The using status detecting section  43  detects using status of the electric components  13 , and the using status predicting section  45  predicts the using status of the electric components  13  from external information. 
   The vehicle running condition detecting section  44  detects vehicle running condition related to idle, acceleration, constant speed, and deceleration, based on information from an electronic control unit that controls an engine of the vehicle, and the vehicle running condition predicting section  46  predicts the vehicle running condition from external information. 
   Based on results of the detection and prediction, the gradual change requirement determining section  47  determines whether it is required or not to perform the gradual change process in which the generating voltage generated by the alternator  12  is gradually changed to the target generating voltage of the alternator  12  and the gradual change rate deciding section  48  decides a gradual change rate indicating a variation width of the generating voltage of the alternator  12  per unit time when the gradual change process is performed. 
   When it is determined that the gradual change process is not required, or when it is determined that a sudden change process is required, the sudden change performing section  49  performs the sudden change process in which the generating voltage of the alternator  12  is suddenly changed to the target generating voltage of the alternator  12 . When it is determined that the gradual change process is required, the gradual change performing section  50  performs the gradual change process based on the decided gradual change rate. Here, since the generating voltage is instantaneously changed to the target generating voltage in the sudden change process, a time period required to change the generating voltage to the target generating voltage in the sudden change process is much shorter than that in the gradual change process. 
   Next, the gradual change requirement determination process of the gradual change requirement determining section  47  will be described. 
   As shown in  FIG. 4 , the gradual change requirement determining section  47  repeatedly performs the following steps according to the program for the gradual change requirement determination process. 
   In the first embodiment, the gradual change requirement determination process is divided into a former stage and a latter stage. 
   [Step S 11 ] The CPU  34  performs the gradual change requirement determination process at the former stage, which is shown in  FIGS. 5 and 6 . 
   [Step S 12 ] The CPU  34  determines whether or not the gradual change process is required, based on a result of the process at Step S 11 . If it is determined that the gradual change process is required, the process proceeds to Step S 13 . Otherwise, the process proceeds to Step S 16 . In Step S 12 , the CPU  34  may also determine whether the gradual change process is required or the sudden change process is required. In this case, if it is determined that the sudden change process is required, the process proceeds to Step S 16 . 
   [Step S 13 ] The CPU  34  performs the gradual change requirement determination process at the latter stage, which is shown in  FIGS. 7 ,  10 ,  11  and  12 . This process is not indispensable but optional. When this process is performed, precision of the gradual change requirement determination process is improved. 
   [Step S 14 ] The CPU  34  determines whether or not the gradual change process is required, based on a result of the process at Step S 13 . If it is determined that the gradual change process is required, the process proceeds to Step S 15 . Otherwise, the process proceeds to Step S 16 . In Step S 14 , the CPU  34  may also determine whether the gradual change process is required or the sudden change process is required. In this case, if it is determined that the sudden change process is required, the process proceeds to Step S 16 . 
   [Step S 15 ] The CPU  34  performs the gradual change process which is shown in  FIG. 17 . 
   [Step S 16 ] The CPU  34  performs the sudden change process which is shown in  FIG. 16 . 
   According to the above-described processes, if it is determined that the gradual change process is required, since the generating voltage of the alternator  12  is gradually changed to the target generating voltage, the voltage of the battery  11  is not suddenly changed, thereby having no effect on operation of the electric components  13 . If it is determined that the gradual change process is not required, since the generating voltage of the alternator  12  is suddenly changed to the target generating voltage, charging efficiency of the battery  11  is improved, whereby the battery  11  is rapidly charged. 
   Now, an example of the process at Step S 11  in  FIG. 4  will be described. For the purpose of performing this process, the gradual change requirement determining section  47  includes programs for a first former gradual change requirement determination process and a second former gradual change requirement determination process, which are selected as necessary. 
   To begin with, the first former gradual change requirement determination process performed by the gradual change requirement determining section  47  will be described. 
   As shown in  FIG. 5 , the gradual change requirement determining section  47  performs the following steps according to the program for the first former gradual change requirement determination process program. 
   [Step S 21 ] The CPU  34  determines whether or not the electric components  13 , for example, a light that flickers the generating voltage of the alternator  12  is suddenly changed and a wiper whose operation speed is rapidly changed when the generating voltage is suddenly changed, are being used. If it is determined that the electric components  13  is used, the process proceeds to Step S 22 . Otherwise, the process proceeds to Step S 23 . 
   [Step S 22 ] Since flickering of the light and change of the operation speed of the wiper can be prevented by preventing the generating voltage of the alternator  12  from being suddenly changed, the CPU  34  determines that the gradual change process to gradually change the generating voltage of the alternator  12  to the target generating voltage is required. 
   [Step S 23 ] Since the electric components  13  such as the light or the wiper is not used, and therefore, its operation is not affected although the voltage of the battery  11  is suddenly changed as the generating voltage of the alternator  12  is suddenly changed, the CPU  34  determines that the gradual change process is not required. 
   According to the above described processes, it is determined whether or not the gradual change process is required, based on the using status of the electric components  13  such as the light that flickers or the wiper whose operation speed is rapidly changed when the generating voltage of the alternator  12  is suddenly changed. 
   Next, the second former gradual change requirement determination process performed by the gradual change requirement determining section  47  will be described. 
   As shown in  FIG. 6 , the gradual change requirement determining section  47  performs the following steps according to a program for the second former gradual change requirement determination process. 
   [Step S 31 ] The CPU  34  acquires information on a position and a driving path of the vehicle, which are acquired by the car navigator  21 . 
   [Step S 32 ] The CPU  34  acquires weather information acquired by the radio  22  through a FM teletext or the like. 
   [Step S 33 ] The CPU  34  acquires time information from a electric component having a clock function. 
   [Step S 34 ] The CPU  34  predicts a using status of the electric components  13  based on the position and driving path information, the weather information and the time information of the vehicle. For example, if the acquired time information indicates evening or if the acquired position and driving path information indicates that the vehicle is about to go into a tunnel, the light is predicted to be turned on. In addition, if the weather information indicates that it is likely to rain, the wiper is predicted to be actuated. 
   [Step S 35 ] The CPU  34  determines whether or not there is one of electric components  13  to be predicted to operate soon. If it is determined that there is one of electric components  13  to be predicted to operate soon, the process proceeds to Step S 36 . Otherwise, the process proceeds to Step S 37 . 
   [Step S 36 ] The CPU  34  determines that the gradual change process is required. 
   [Step S 37 ] The CPU  34  determines that the gradual change process is not required. 
   According to the above-described processes, it is determined whether or not the gradual change process is required, based on the predicted using status of the electric component such as the light or wiper. 
   Next, an example of the process at Step S 13  in  FIG. 4  will be described. For the purpose of performing this process, the gradual change requirement determining section  47  includes programs for a first latter gradual change requirement determination process, a second latter gradual change requirement determination process, a third gradual change requirement determination process, and/or a fourth latter gradual change requirement determination process, which are selected as necessary. 
   To begin with, the first latter gradual change requirement determination process performed by the gradual change requirement determining section  47  will be described. 
   If it is determined that the gradual change process is required after completion of Step S 12 , as shown in  FIG. 7 , the gradual change requirement determining section  47  performs the following steps according to the program for the first latter gradual change requirement determination process. 
   [Step S 41 ] The CPU  34  acquires the voltage of the battery  11 , which is detected by the voltage sensor  15 , and a charging rate according to the voltage. 
   Here, the charging rate is acquired based on the acquired voltage of the battery  11 . That is, as shown in  FIG. 8 , since the battery  11  has a characteristic that the charging rate is varied depending on the voltage Vb, the CPU  34  acquires the charging rate corresponding to the voltage Vb of the battery  11  from the ROM  35  in which data on the voltage characteristic of the battery  11  are stored. In addition, since the battery  11  has a characteristic that the charging rate is varied depending on the liquid temperature Tb, it is necessary to correct the charging rate depending on the liquid temperature Tb. Accordingly, the CPU  34  acquires a correction coefficient of the charging rate corresponding to the liquid temperature of the battery  11  from the ROM  35  in which data on the temperature characteristic as shown in  FIG. 9  are stored, and corrects the charging rate of the battery  11  by multiplying the charging rate of the battery  11  by the correction coefficient. 
   [Step S 42 ] The CPU  34  acquires vehicle running condition related to idle, acceleration, constant speed and deceleration and determines whether or not the vehicle running condition are varied, based on information from the electronic control unit that controls the engine of the vehicle. If it is determined that the vehicle running condition are varied, the process proceeds to Step S 43 . Otherwise, the process proceeds to Step S 45 . 
   [Step S 43 ] The CPU  34  acquires a generating voltage Va 1  of the alternator  12  detected by the voltage sensor  19 . 
   [Step S 44 ] The CPU  34  acquires a target generating voltage Va 2 . Since the target generating voltage Va 2  of the alternator  12  is set depending on the vehicle running condition, the CPU  34  acquires the target generating voltage Va 2  corresponding to variation of the vehicle running condition. 
   [Step S 45 ] The CPU  34  determines whether or not the voltage or charging rate of the battery  11  is more than a predetermined value. If it is determined that the voltage or charging rate of the battery  11  is more than the predetermined value, the process proceeds to Step S 48 . Otherwise, the process proceeds to Step S 46 . 
   [Step S 46 ] The CPU  34  determines whether or not the vehicle running condition is in deceleration. If it is determined that the vehicle running condition is in deceleration, the process proceeds to Step S 47 . Otherwise, the process proceeds to Step S 48 . 
   [Step S 47 ] The CPU  34  determines that the gradual change process is not required. 
   The processes in Steps S 45 , S 46  and S 47  instantaneously change the generating voltage of the alternator  12  to the target generating voltage by forcibly making the gradual change process unnecessary in a case where the vehicle running condition is in deceleration in which the alternator  12  can generate more power when the voltage or charging rate of the battery is decreased. Accordingly, the battery  11  whose voltage or charging rate is decreased can be rapidly charged in deceleration of the vehicle. 
   [Step S 48 ] The CPU  34  determines whether or not a difference between the target generating voltage Va 2  and the generating voltage Va 1  of the alternator  12  is more than a predetermined value. If it is determined that the difference is more than the predetermined value, the process proceeds to Step S 49 . Otherwise, the process proceeds to Step S 47 . 
   [Step S 49 ] Since the difference between the generating voltage of the alternator  12  and the target generating voltage is large, The CPU  34  determines that the gradual change process is required to prevent the generating voltage of the alternator  12  from being suddenly changed. 
   According to the above-described processes, it is determined whether or not the gradual change process is required, based on the difference between the target generating voltage Va 2 , which corresponds to the vehicle running condition, and the generating voltage Va 1  of the alternator  12 . 
   Next, the second latter gradual change requirement determination process performed by the gradual change requirement determining section  47  will be described. 
   As shown in  FIG. 10 , the second latter gradual change requirement determination process is different from the first latter gradual change requirement determination process in that the target generating voltage Va 2  and the generating voltage Va 1  of the alternator  12  are changed to target power Pa 2  and present power Pa 1  of the alternator  12 , respectively. Thus, in Step S 58 , the CPU  34  determines whether or not a difference between the target power Pa 2  and the present power Pa 1  of the alternator  12  is more than a predetermined value. Power of the alternator  12  is calculated from the generating voltage and generating current of the alternator  12 , which are detected by the voltage sensor  19  and the current sensor  20 , respectively. 
   According to the above-described processes, it is determined whether or not the gradual change process is required, based on the difference between the target power based on the target generating voltage, which corresponds to the vehicle running condition, and the present power based on the generating voltage of the alternator  12 . 
   Next, the third latter gradual change requirement determination process performed by the gradual change requirement determining section  47  will be described. 
   If it is determined that the gradual change process is required after completion of Step S 12 , as shown in  FIG. 11 , the gradual change requirement determining section  47  performs the following steps according to the program for the third latter gradual change requirement determination process. 
   [Step S 61 ] The CPU  34  acquires the voltage of the battery  11 , which is detected by the voltage sensor  15 , or a charging rate according to the voltage. 
   [Step S 62 ] The CPU  34  acquires information on a position and a driving path of the vehicle, which are acquired by the car navigator  21 . 
   [Step S 63 ] The CPU  34  predicts the vehicle running condition based on the information on the position and the driving path of the vehicle. For example, the vehicle running condition is predicted to change to acceleration if the vehicle encounters an uphill road, while the vehicle running condition is predicted to change to deceleration if the vehicle encounters a downhill road. In addition, the vehicle running condition is predicted to change to deceleration if a traffic light is predicted to turn red. 
   [Step S 64 ] The CPU  34  determines whether or not the vehicle running condition is changed, based on a result of the prediction in Step S 63 . 
   If it is determined that the vehicle running condition is changed, the process proceeds to Step S 65 . Otherwise, the process proceeds to Step S 67 . 
   [Step S 65 ] The CPU  34  acquires the generating voltage Va 1  of the alternator  12 , which is detected by the voltage sensor  19 . 
   [Step S 66 ] The CPU  34  acquires the target generating voltage Va 2  of the alternator  12 . 
   [Step S 67 ] The CPU  34  determines whether or not the voltage or the charging rate of the battery  11  is more than a predetermined value. If it is determined that the voltage or the charging rate of the battery  11  is more than the predetermined value, the process proceeds to Step S 70 . Otherwise, the process proceeds to Step S 68 . 
   [Step S 68 ] The CPU  34  determines whether or not the vehicle running condition is in deceleration. If it is determined that the vehicle running condition is in deceleration, the process proceeds to Step S 69 . Otherwise, the process proceeds to Step S 70 . 
   [Step S 69 ] The CPU  34  determines that the gradual change process is not required. 
   [Step S 70 ] The CPU  34  determines whether or not a difference between the target generating voltage Va 2  and the generating voltage Va 1  of the alternator  12  is more than a predetermined value. If it is determined that the difference is more than the predetermined value, the process proceeds to Step S 71 . Otherwise, the process proceeds to Step S 69 . 
   [Step S 71 ] The CPU  34  determines that the gradual change process is required. 
   According to the above-described processes, it is determined whether or not the gradual change process is required, based on the difference between the target generating voltage, which corresponds to the predicted vehicle running condition, and the generating voltage of the alternator  12 . 
   Next, the fourth latter gradual change requirement determination process performed by the gradual change requirement determining section  47  will be described. 
   As shown in  FIG. 12 , the fourth latter gradual change requirement determination process is different from the third latter gradual change requirement determination process in that the target generating voltage Va 2  and the generating voltage Va 1  of the alternator  12  are changed to target power Pa 2  and present power Pa 1  of the alternator  12 , respectively. Thus, in Step S 90 , the CPU  34  determines whether or not a difference between the target power Pa 2  and the present power Pa 1  of the alternator  12  is more than a predetermined value. 
   According to the above-described processes, it is determined whether or not the gradual change process is required, based on the difference between the target power based on the target generating voltage, which corresponds to the predicted vehicle running condition, and the present power based on the generating voltage of the alternator  12 . 
   Next, the gradual change rate decision process performed by the gradual change rate deciding section  48  will be described. 
   If it is determined that the gradual change process is required according to the processes of the flow chart of  FIG. 4 , as shown in  FIG. 13 , the gradual change rate deciding section  48  performs the following steps according to the program for the gradual change decision process. 
   [Step S 101 ] The CPU  34  acquires the voltage of the battery  11 , which is detected by the voltage sensor  15 , or a charging rate according to the voltage. 
   [Step S 102 ] The CPU  34  acquires information on running condition of the vehicle before being changed, and running condition of the vehicle after being changed, based on information from the electronic control unit that controls the engine of the vehicle. 
   [Step S 103 ] The CPU  34  determines whether or not the voltage or charging rate of the battery  11  is more than a predetermined value. If it is determined that the voltage or charging rate of the battery  11  is more than the predetermined value, the process proceeds to Step S 104 . Otherwise, the process proceeds to Step S 106 . 
   [Step S 104 ] The CPU  34  selects the first gradual change rate table for deciding gradual change rates. As shown in  FIG. 14 , gradual change rates based on the running condition of the vehicle before being changed, the running condition of the vehicle after being changed, and determination on whether or not the power of the alternator  12  is cut are stored in the first gradual change rate table. 
   [Step S 105 ] The CPU  34 , refers to the ROM  35  in which the first gradual change rate table is stored, and then decides a gradual change rate based on running condition of the vehicle before being changed, the running condition of the vehicle after being changed, and the determination on whether or not power of the alternator  12  is cut. 
   Here, the electronic control it that controls the engine of the vehicle has a function to prioritize torque of the engine over generating the power when the running condition is acceleration. With this function, the target generating voltage of the alternator  12  is cut by, for example, 5%. In this case, the gradual change rate is set to be high and the generating voltage of the alternator  12  is suddenly changed to the target generating voltage, and therefore, the torque of the engine is raised. 
   [Step S 106 ] The CPU  34  selects the second gradual change rate table for deciding the gradual change rate. As shown in  FIG. 15 , gradual change rate based on the running condition of the vehicle before being changed and the running condition of the vehicle after being changed are stored in the second gradual change rate table. Since the gradual change rate is set to be higher in the second gradual change rate table than the first gradual change rate table, it is prioritized to charge the battery  11  when the voltage or charging rate of the battery  11  is low. 
   [Step S 107 ] The CPU  34  decides a gradual change rate, based on the running condition of the vehicle before being changed and the running condition of the vehicle after being changed by referring to the ROM  35  in which the second gradual change rate table is stored. According to the above-described processes, one of the first and second gradual change rate tables is selected based on the voltage or charging rate of the battery  11 . Specifically, when the first gradual change rate table in which low gradual change rates are set is selected, a gradual change rate is decided based on change of the vehicle rung condition and the determination on whether or not the power of the alternator  12  is cut, and, when the second gradual change rate table in which high gradual change rates are set is selected, a gradual change rate is decided based on change of the vehicle running condition. 
   Next, a sudden change process performed by the sudden change performing section  49  will be described. 
   As shown in  FIG. 16 , the sudden change performing section  49  performs the following steps according to the program fox the sudden change process. 
   [Step S 121 ] The CPU  34  acquires the target generating voltage Va 2  of the alternator  12 , which is acquired by the processes of the flow chart of  FIG. 4 . 
   [Step S 122 ] The CPU  34  performs the sudden change process in which the generating voltage Va 1  of the alternator  12  is suddenly changed to the target generating voltage Va 2 . 
   Next, a gradual change process performed by the gradual change performing section  50  will be described. 
   As shown  FIG. 17 , the gradual change performing section  50  performs the following steps according to the program for the gradual change process. 
   [Step S 111 ] The CPU  34  acquires the gradual change rate decided in Step S 105  or Step  107 . 
   [Step S 112 ] The CPU  34  acquires the target generating voltage Va 2  of the alternator  12 , which is acquired by the processes of the flow chart of  FIG. 4 . 
   [Step S 113 ] The CPU  34  performs the gradual change process in which the generating voltage of the alternator  12  is gradually changed to the target generating voltage according to the acquired gradual change rate. 
   In addition, although the charging control apparatus  10  is provided independently in the first embodiment, it may be built in the electronic control unit. 
   Hereinafter, a second embodiment of a charging control apparatus will be described in detail with reference to the accompanying drawings. 
   As shown in  FIG. 18 , a charging control apparatus  1  includes a vehicle condition detecting section  1   a , a target electric quantity determining section  1   b , a correction value storing section  1   c , a correction value acquiring section  1   d , and a target electric quantity correcting section  1   e . In addition, the charging control apparatus  1  is connected to a battery  2 , a sensor  3  and an electric generator (alternator)  4 . 
   The vehicle condition detecting section  1   a  detects vehicle conditions from the battery  2  and the sensor  3 . For example, the vehicle condition detecting section  1   a  detects a voltage or a current output from the battery  2 . In addition, the vehicle condition detecting section  1   a  detects using status of electric components installed in the vehicle from the sensor  3 , and, for example, detects running condition of the vehicle from a throttle valve opening angle, a vehicle speed, RPM (revolution per minute) of an engine, etc. 
   The target electric quantity determining section  1   b  acquires information on vehicle conditions from the vehicle condition detecting section  1   a  and determines a target electric quantity to be output from the electric generator  4 . Specifically, the target electric quantity determining section  1   b  acquires a voltage and current of the battery  2  from the vehicle condition detecting section  1   a  and determines the target electric quantity to be generated by the electric generator  4  from the voltage and current of the battery  2  and a target voltage of the battery  2 . 
   The correction value storing section  1   c  preliminarily stores a correction value to correct the target electric quantity, which is determined by the target electric quantity determining section  1   b , based on the vehicle conditions detected by the vehicle condition detecting section  1   a.    
   The correction value acquiring section  1   d  acquires information on the vehicle conditions detected by the vehicle condition detecting section  1   a . In addition, the correction value acquiring section  1   d  acquires the correction value to correct the target electric quantity based on the information on the vehicle conditions from the correction value storing section  1   c.    
   Upon acquiring information on the target electric quantity from the target electric quantity determining section  1   b , the target electric quantity correcting section  1   e  acquires the correction value to correct the target electric quantity from the correction value acquiring section  1   d . Then, the target electric quantity correcting section  1   e  corrects the target electric quantity with the acquired correction value and instructs the electric generator  4  to charge the battery  2 . 
   According to the instruction to charge the battery  2 , the electric generator  4  outputs the electric quantity to charge the battery  2  based on the target electric quantity which is instructed by the target electric quantity correcting section  1   e.    
   With the charging control apparatus  1  constructed as above, the vehicle condition detecting section  1   a  detects the vehicle conditions, the correction value acquiring section  1   d  reads the correction value to correct the target electric quantity based on the vehicle conditions from the correction value storing section  1   c , and the target electric quantity correcting section  1   e  corrects the target electric quantity based on the read correction value. Accordingly, the target electric quantity is corrected with the correction value suitable for the vehicle conditions. Thus, the electric generator  4  can rapidly charge the battery  2 . 
   Next, an embodiment in which the charging control apparatus according to the second embodiment is applied to a master ECU will be described. 
   As shown in  FIG. 19 , a master ECU (Electronic Control Unit)  100 , a battery  200  and an alternator (ALT)  300  are interconnected via a power line  400 . In addition, a navigator  500  is connected to the master ECU  100 . 
   The battery  200  is connected to a voltmeter  210  that measures a voltage of the battery  200 , an ammeter  220  that measures a current of the battery  200 , and a thermometer  230  that measures a liquid temperature of the battery  200 . 
   The master ECU  100  detects vehicle conditions via wires that interconnect the voltmeter  210 , the ammeter  220 , the thermometer  230  and the master ECU  100 . For example, the master ECU  100  detects the voltage and current of the battery  200  from the voltmeter  210  and the ammeter  220 , respectively. In addition, the master ECU  100  detects vehicle conditions including, for example, using status of electric components installed in a vehicle, vehicle situation indicating acceleration or deceleration of a vehicle, external environments of a vehicle, such as traffic congestion, atmospheric temperature, remaining fuel of a vehicle, via the wires from sensors (not shown) sensing the vehicle conditions. In addition, the master ECU  100  detects liquid temperature of the battery  200  from the thermometer  230 . 
   In addition, the master ECU  100  calculates the target electric quantity to be output by the alternator  300 , based on a target charging voltage of the battery  200  and the detected voltage of the battery  200 . In this case, the target electric quantity may be a target power to be generated by the alternator  300 . On the other hand, the master ECU  100  calculates a correction value to correct the calculated target electric quantity, based on the detected vehicle conditions. In addition, the master ECU  100  corrects the target electric quantity to be output by the alternator  300 , based on the calculated correction value, and outputs an instruction signal to the alternator  300  via a communication bus  410 . 
   Upon receiving the instruction signal from the master ECU  100 , the alternator  300  output the electric quantity based on the instruction signal including the target electric quantity and charges the battery  200 . In addition, the alternator  300  supplies the electric quantity to electric components installed in the vehicle. In this case the electric quantity may be a power generated by the alternator  300 . 
   As shown in  FIG. 20 , the master ECU  100  comprises a microcomputer  101 , an I/F (interface)  102  and a bus  103 , and is connected to, for example, an external bus  400  via the I/F  102 . 
   The microcomputer  101  comprises a CPU (Central Processing Section)  101   a , a ROM (Read Only Memory)  101   b  and a RAM (Random Access Memory)  101   c . The master ECU  100  is controlled as a whole by the CPU  101   a . The ROM  101   b  and the RAM  101   c  are connected to the CPU  101   a  via an internal bus  101   d  of the microcomputer  101 . 
   A program of an OS (Operating System) or at least a part of an application program to be executed by the CPU  101   a  is temporarily stored in the RAM  101   c . In addition, various kinds of data required for processes by the CPU  101   a  are stored in the RAM  101   c . An OS and application programs are stored in the ROM  101   b.    
   In addition, hardware of the master ECU  100  is not limited to the configuration shown in  FIG. 20 . For example, a ROM may be connected to the bus  103  and the OS or the application programs may be stored in this ROM. In addition, a RAM may be connected to the bus  103  and data may be temporarily stored in this RAM. Various process functions of the second embodiment can be realized by the above-described hardware configuration. 
   Next, process functions of the master ECU  100  will be described. 
   As shown in  FIG. 21 , the master ECU  100  comprises a vehicle condition detecting section  110 , a target voltage storing section  120 , a power generation amount calculating section  130 , a charging rate storing section  140 , a charging rate acquiring section  150 , a correction value storing section  160 , a correction processing section  170  and a predetermined time storing section  180 . 
   The vehicle condition detecting section  110  detects vehicle conditions. The vehicle conditions refer to conditions of the battery installed in a vehicle, using status of electric components installed in a vehicle, vehicle situation indicating, such as acceleration or deceleration of a vehicle, external information of a vehicle, such as traffic congestion on a traveling path to a destination set in a vehicle and atmospheric temperature, remaining fuel of a vehicle, etc. 
   The vehicle condition detecting section  110  comprises a battery condition detecting section  111 , an electric component using status detecting section  112 , a vehicle situation detecting section  113 , an external environment detecting section  114  and a remaining fuel detecting section  115  for detecting various conditions of the vehicle. 
   The battery condition detecting section  111  detects the voltage of the battery  200  from the voltmeter  210 , the current from the ammeter  220 , and the liquid temperature from the thermometer  230 . 
   The electric component using status detecting section  112  detects the using status of the electric components installed in the vehicle. For example, the electric component using status detecting section  112  detects whether or not an air conditioner installed in the vehicle is used and intensity of wind from the air conditioner. Specifically, the electric component using status detecting section  112  detects using status of the air conditioner from an ECU attached to the air conditioner. 
   The vehicle situation detecting section  113  detects vehicle situation that indicates running condition of the vehicle, such as acceleration, deceleration, constant speed, idle or racing, which are obtained based on a throttle valve opening angle, RPM (revolution per minute) of an engine, a vehicle speed, etc., from sensors (not shown). 
   The external environment detecting section  114  detects external environments of the vehicle, which are external information related to running of the vehicle. Specifically, the external environment detecting section  114  detects external information such as traffic congestion on a traveling path to a destination set in the navigator  500  connected to the master ECU  100 , weather information such as atmospheric temperature. 
   The remaining fuel detecting section  115  detects remaining fuel of the vehicle. 
   The target voltage storing section  120  stores a voltage at which the battery is full-charged, as a target voltage for charging of the battery  200  (Namely, a target charging voltage of the battery). 
   The power generation amount calculating section  130  acquires the target charging voltage of the battery  200  from the target voltage storing section  120  and acquires the voltage of the battery  200  from the battery condition detecting section  111 . In addition, based on a difference between both voltages, the power generation amount calculating section  130  calculates a target voltage to be generated by the alternator  300 . 
   A battery charging rate corresponding to an open voltage of the battery  200  is stored in the charging rate storing section  140 . In addition, a correction value to correct the battery charging rate corresponding to liquid temperature of the battery  200  is stored in the charging rate storing section  140 . 
   Hereinafter, a relationship between the open voltage of the battery and the battery charging rate which is stored in the charging rate storing section  140  and a relationship between the liquid temperature and the battery charging rate will be described. 
   As shown in  FIG. 22 , a voltage-charging rate graph  141  shows that the battery charging rate is set to correspond to the open voltage of the battery  200 . That is, the battery charging rate can be obtained by the open voltage of the battery  200 , which is calculated by the master ECU  100 , and the voltage-charging rate graph  141  which is stored in the charging rate storing section  140 . 
   The voltage-charging rate graph  141  shows that the battery charging rate increases as the open voltage increases. That is, when the battery  200  is charged and the open voltage is calculated, if the open voltage increases with respect to the open voltage calculated before charging, the battery charging rate increases. 
   As shown in  FIG. 23 , a liquid temperature-correction value graph  142  shows that a correction value to correct the battery charging rate is set to correspond to the liquid temperature. 
   In addition, the liquid temperature-correction value graph  142  shows that the correction value is 1 when the liquid temperature is 25° C. That is, there is no need to correct the battery charging rate obtained from the open voltage shown in  FIG. 22  when the liquid temperature is 25° C. In addition, the battery charging rate is corrected by multiplying the battery charging rate obtained from the open voltage by the correction value. 
   Returning to  FIG. 21 , process functions of the master ECU  100  will be described. 
   The charging rate acquiring section  150  acquires the voltage and the current of the battery  200  from the battery condition detecting section  111  and calculates an internal resistance of the battery  200  based on the acquired voltage and current. In addition, the charging rate acquiring section  150  calculates the open voltage of the battery based on the voltage and the current of the battery  200  and the calculated internal resistance of the battery  200 . The open voltage is calculated according to the following equation (1).
 
Voltage of battery 200−(current of battery 200×internal resistance of battery 200)=open voltage of battery  (1)
 
   In the above equation (1), a term in parentheses is positive when the battery  200  is charged and the term in parentheses is negative when the battery  200  is discharged. 
   After calculating the open voltage, the charging rate acquiring section  150  acquires the battery charging rate corresponding to the open voltage from the charging rate storing section  140 . In addition, the charging rate acquiring section  150  acquires the liquid temperature from the battery condition detecting section  111  and the correction value of the battery charging rate corresponding to the liquid temperature, and corrects the calculated battery charging rate based on the acquired correction value. The charging rate acquiring section  150  instructs the correction processing section  170  to correct a voltage calculated by the power generation amount calculating section  130  if the corrected battery charging rate is less than a predetermined value. 
   For example, the charging rate acquiring section  150  instructs the correction processing section  170  to correct the voltage if the corrected battery charging rate is less than 75%. Specifically, the charging rate acquiring section  150  instructs the correction processing section  170  to intermittently correct the voltage if the corrected battery charging rate is between 50 to 75% and constantly correct the voltage if the corrected battery charging rate is less than 50%. 
   A correction value to correct the voltage calculated by the power generation amount calculating section  130  is stored in the correction value storing section  160  in correspondence to vehicle conditions. For example, the correction value to correct the voltage is stored in correspondence to the battery charging rate, the liquid temperature, the amount of current consumed by the electric components, and the running condition of the vehicle. 
   Hereinafter, a relationship between the correction value and each of the battery charging rate, the liquid temperature and the consumption current consumed by the electric components, which are stored in the correction value storing section  160 , will be described. 
   As shown in  FIG. 24 , a charging rate-correction value graph  161  shows that the correction value to correct the voltage calculated by the power generation amount calculating section  130  is set to correspond to the battery charging rate. 
   This correction value is set to be low when the battery charging rate is high and to be high when the battery charging rate is low. This is based on the requirement that the battery charging rate has to increase faster as the battery charging rate is lower since a danger of rising of a battery voltage increases as the battery charging rate is lower. 
   As shown in  FIG. 25 , a liquid temperature-correction value graph  162  shows that the correction value to correct the voltage calculated by the power generation amount calculating section  130  is set to correspond to the liquid temperature. 
   This correction value is set to be low when the liquid temperature is high and to be high when the liquid temperature is low. This is based on the requirement that the battery  200  has to be charged to a high voltage when the liquid temperature is low, which is higher than a voltage when the liquid temperature is high, since acceptance of a charging current is deteriorated when the liquid temperature is low. 
   As shown in  FIG. 26 , a current-correction value graph  163  shows that the correction value to correct the voltage calculated by the power generation amount calculating section  130  is set to correspond to the consumption current of the electric component installed in the vehicle. 
   This correction value is set to be high when the consumption current of the electric component is large and to be low when the consumption current of the electric component is small. This is based on the requirement that the alternator  300  has to output higher power since power generated by the alternator  300  is consumed in bulk in the electric component when the consumption current is large. 
   Returning to  FIG. 21  again, process functions of the master ECU  100  will be further described. 
   Upon receiving an instruction to correct the voltage calculated by the power generation amount calculating section  130  from the charging rate acquiring section  150 , the correction processing section  170  acquires vehicle condition information related to the vehicle conditions from the vehicle condition detecting section  110 . In addition, the correction processing section  170  uses the acquired vehicle condition information to acquire the correction value of the voltage from the correction value storing section  160 . Further, the correction processing section  170  uses the acquired correction value to correct the voltage calculated by the power generation amount calculating section  130 , and instructs the alternator  300  to output the corrected voltage. 
   When the corrected voltage is output from the alternator  300  and the battery  200  is charged, the correction processing section  170  monitors the voltage of the battery  200  for a predetermined period of time to determine whether or not the voltage increases. If it is determined that the voltage does not increase for the predetermined period of time, the correction processing section  170  corrects the voltage again and instructs the alternator  300  to output a higher voltage. 
   If it is determined that the alternator  300  has insufficient capability to supply the power to electric components, the feed of the power to the electric components is restricted depending on the battery charging rate and remaining fuel. In this case, the feed of power to an electric component having no direct relation to running of the vehicle is preferentially restricted. 
   For example, when the external environment detecting section  114  detects brightness in the outside of the vehicle through an optical sensor, if a light of the vehicle is turned on although it is determined that it is bright in the outside of the vehicle, the light is turned off. In addition, if an air conditioner is turned on although temperature in the outside of the vehicle is low, the air conditioner is turned off. 
   If the voltage calculated by the power generation amount calculating section need not be urgently corrected, it may be intermittently corrected. For example, if the amount of remaining fuel is less than a predetermined value or if the battery charging rate is less than a predetermined value, it may be intermittently corrected. 
   Interruption time of the correction process and execution time of the intermittent correction process when the correction processing section  170  performs the intermittent correction process, and a time taken from the voltage correction process to determination on whether or not the correction process is performed again are stored in the predetermined time storing section  180 . 
   Hereinafter, a relationship between the vehicle condition information and each of the times which is stored in the predetermined time storing section  180 , will be described using a graph. 
   As shown in  FIG. 27 , a charging rate-determination time graph  181  shows that a determination time to determine whether or not the voltage correction process is performed again is set to correspond to the battery charging rate. 
   The determination time is set to be long when the battery charging rate is high and short when the battery charging rate is low. This is based on the requirement that the battery charging rate has to increase faster as the battery charging rate is lower since a danger of rising of a battery voltage increases as the battery charging rate is lower. 
   As shown in  FIG. 28 , a charging rate-interruption time graph  182  shows that an interruption time of the intermittent voltage correction process is set to correspond to the battery charging rate. 
   The interruption time is set to be long when the battery charging rate is high and short when the battery charging rate is low. This is based on the requirement that the battery charging rate has to increase faster as the battery charging rate is lower since a danger of rising of a battery voltage increases as the battery charging rate is lower. 
   As shown in  FIG. 29 , a remaining fuel-elapse time graph  183  shows that a time elapsed from initiation of the intermittent voltage correction process is set to correspond to the remaining fuel. The intermittent voltage correction process is stopped when a predetermined elapse time passes. 
   The elapse time is set to be long when the amount of remaining fuel is large and short when the amount of remaining fuel is small. This is based on the requirement that the time taken to perform the voltage correction process that consumes fuel has to be set to be shorter as the amount of remaining fuel is smaller since a danger of lack of gas increases as the amount of remaining fuel is smaller. On the other hand, as the amount of remaining fuel is larger, the time taken to perform the voltage correction process is set to be longer. 
   Next, examples of various kinds of data stored in the master ECU  100  will be described. 
   A charging rate-correction value table  164 , as shown in  FIG. 30 , is stored in the correction value storing section  160  and shows battery charging rates and corresponding correction values, with a pair of a battery charging rate and a corresponding correction value forming a record. 
   The battery charging rates of the battery  200  are set to decrease by 5% from 75% to 55%. The correction values are set as voltage values to be added to the voltage calculated by the power generation amount calculating section  130  when the voltage correction process is performed. 
   As shown in the charging rate-correction value graph  161  of  FIG. 24 , the correction value is set to be large as the battery charging rate is lowered. In addition, setting the battery charging rate to start from 75% is based on the requirement that the voltage correction process should not be performed when the battery charging rate exceeds 75%. 
   A vehicle condition-correction value table  165 , as shown in  FIG. 31 , is stored in the correction value storing section  160 . The vehicle condition-correction value table  165  shows vehicle conditions and corresponding correction values, with a pair of a vehicle condition and a corresponding correction value forming a record. 
   The vehicle conditions are set to be acceleration, idle, constant speed, and deceleration-racing. The correction values are set to be X 1 , X 2 , X 3  and X 4 . 
   In this example, the set correction values have a relationship of X 1 &lt;X 2 &lt;X 3 &lt;X 4 . This relationship is set since, if the voltage calculated by the power generation amount calculating section  130  is corrected to be high in acceleration of the vehicle, torque, which is generated in an engine of the vehicle and has to be used for acceleration of the vehicle, is much used to generate power in the alternator  300 , which results in deterioration of driving efficiency. 
   In deceleration or racing of the vehicle, contrary to the acceleration, the driving efficiency is not affected since there is no need for torque to accelerate the vehicle even if the voltage calculated by the power generation amount calculating section  130  is corrected to be high, and the torque generated in the engine of the vehicle is used to generate power in the alternator  300 . Accordingly, the correction values are set to be small in the acceleration and large in the deceleration-racing. 
   The master ECU  100  having the above-described functions and data performs the following processes. 
   Hereinafter, the flow chart of  FIG. 32  will be described with step numbers. 
   [Step S 211 ] The battery condition detecting section  111  detects a voltage, current and liquid temperature of the battery. The electric component using status detecting section  112  detects using status of electric components installed in a vehicle. Specifically, the amount of current consumed by the electric components is detected. 
   The vehicle situation detecting section  113  detects vehicle conditions including acceleration, idle, constant speed, deceleration, and racing. The external environment detecting section  114  detects information on traffic congestion on a path to a destination set in the navigator  500  and information on atmospheric temperature. The remaining fuel detecting section  115  detects the amount of remaining fuel of the vehicle. 
   [Step S 212 ] The power generation amount calculating section  130  acquires a target voltage of the battery  200  from the target voltage storing section  120  and a voltage of the battery  200  from the battery condition detecting section  111 , and, based on a difference between both acquired voltages, calculates a voltage to be generated by the alternator  300 . 
   [Step S 213 ] The charging rate acquiring section  150  acquires the voltage and current of the battery  200  from the battery condition detecting section  111  and calculates an internal resistance of the battery  200  based on the acquired voltage and current. In addition, the charging rate acquiring section  150  calculates an open voltage of the battery  200  based on the voltage, current and internal resistance of the battery  200  and acquires a battery charging rate using the calculated open voltage. In addition, the charging rate acquiring section  150  determines whether or not the voltage calculated by the power generation amount calculating section  130  is to be corrected from the acquired battery charging rate. 
   For example, if a threshold value is pre-set to be 75% of the battery charging rate, the charging rate acquiring section  150  determines whether or not the voltage calculated by the power generation amount calculating section  130  is to be corrected depending on whether or not the acquired battery charging rate exceeds the threshold value. If it is determined that the voltage is to be corrected, the process proceeds to Step S 214 . Otherwise, the process returns. 
   [Step S 214 ] The correction processing section  170  acquires information on the remaining fuel of the vehicle from the remaining fuel detecting section  115  and information on a distance to the destination set in the navigator  500  and traffic congestion on the path to the destination from the external environment detecting section  114 . Based on the information on the distance to the destination and the traffic congestion on the path to the destination, the correction processing section  170  calculates the minimal amount of fuel required to arrive at the destination. 
   For example, assuming that fuel efficiency of the vehicle is 10 km/L, a distance to the destination set in the navigator  500  is 50 km, and a 2 km interval is in traffic congestion, the minimal amount of fuel required to arrive at the destination can be calculated to be (5+offset value)L according to the following equation (2).
 
(Distance to destination/fuel efficiency)+offset of excessive fuel consumption in traffic congestion=minimal amount of fuel required to arrive at destination  (2)
 
   Here, when the offset of excessive fuel consumption in traffic congestion is expressed by the following equation (3), the minimal amount of fuel required to arrive at destination is calculated to be 7 L.
 
Traffic congestion distance×1=offset of excessive fuel consumption in traffic congestion  (3)
 
   The correction processing section  170  takes the calculated minimal amount of fuel required to arrive at destination as a threshold value A and determines whether or not the amount of remaining fuel of the vehicle exceeds the threshold value A. If it is determined that the amount of remaining fuel of the vehicle does not exceed the threshold value A, the process proceeds to Step S 225  to intermittently perform the voltage correction process that relatively much consumes fuel. If it is determined that the amount of remaining fuel of the vehicle exceeds the threshold value A, the process proceeds to Step S 215 . 
   [Step S 215 ] The correction processing section  170  acquires the battery charging rate from the charging acquiring part  150  and determines whether or not the battery charging rate is less than a predetermined threshold value B. If it is determined that the battery charging rate is more than the threshold value B, the process proceeds to Step S 225  to intermittently perform the voltage correction process although there is a need to fully perform the voltage correction process since the battery charging rate is less than 75% as determined in Step S 213 . If it is determined that the battery charging rate is less than the threshold value B, it is determined that the voltage correction process has to be fully performed, and thus, the process proceeds to Step S 225 . 
   [Step S 216 ] The correction processing section  170  acquires the vehicle condition information from the vehicle condition detecting section  110 . In addition, based on the acquired vehicle condition information, the correction processing section  170  acquires the correction value to correct the voltage calculated by the power generation amount calculating section  130  from the correction value storing section  160 . 
   When the correction value to correct the voltage is in correspondence to the battery charging rate, the liquid temperature, the using status of the electric components, for example, the amount of current consumed by the electric components, and the vehicle conditions, the correction processing section  170  acquires the battery charging rate from the charging rate acquiring section  150 , the liquid temperature from the battery condition detecting section  111 , the amount of current consumed by the electric components from the electric component using status detecting section  112 , and the vehicle conditions from the vehicle situation condition  113 . In addition, based on the acquired vehicle condition information, the correction processing section  170  acquires the correction value from the correction value storing section  160  and corrects the voltage. The correction processing section  170  may correct the voltage using each or all of correction values corresponding to the vehicle conditions. If the correction processing section  170  corrects the voltage using all of the correction values, the correction processing section  170  calculates a correction value by multiplying the correction values corresponding to the vehicle together and corrects the voltage using the calculated correction value (hereinafter referred to as first voltage correction). 
   [Step S 217 ] The correction processing section  170  instructs the alternator  300  to output a voltage after the first voltage correction. 
   [Step S 218 ] The correction processing section  170  acquires the battery charging rate from the charging rate acquiring section  150  and acquires a determination time to determine whether or not the voltage correction process is again performed from the predetermined time storing section  180  using the acquired battery charging rate. In addition, the correction processing section  170  instructs the alternator  300  to output the voltage and determines whether or not the acquired determination time elapses. If it is determined that the acquired determination time elapses, the process proceeds to Step S 219 . 
   [Step S 219 ] The correction processing section  170  acquires the voltage of the battery  200  from the battery condition detecting section  111 , instructs the alternator  300  to output the voltage, as described in Step S 217 , and determines whether or not a voltage of the battery  200  charged by the voltage output from the alternator  300  increases. If it is determined that the voltage of the battery  200  does not increase, the process proceeds to Step S 220 . If it is determined that the voltage of the battery  200  increases, the process proceeds to Step S 222 . 
   [Step S 220 ] The correction processing section  170  calculates a correction value to correct the voltage after the first voltage correction, which is calculated in Step S 216 , and corrects the voltage after the first voltage correction based on the calculated correction value (hereinafter referred to as second voltage correction). For example, a preset correction value is added to the voltage after the first voltage correction. 
   [Step S 221 ] The correction processing section  170  instructs the alternator  300  to output a voltage after the second voltage correction, which is corrected again in Step S 220 . 
   [Step S 222 ] The correction processing section  170  acquires the battery charging rate from the charging rate acquiring section  150  and determines whether or not the battery charging rate is less than a preset threshold value C. If it is determined that the battery charging rate is less than the threshold value C, the process proceeds to Step S 223 . If it is determined that the battery charging rate is more than the threshold value C, the process returns. 
   [Step S 223 ] The correction processing section  170  acquires the amount of remaining fuel of the vehicle from the remaining fuel detecting section  115  and determines whether or not the amount of remaining fuel is less than a preset threshold value D. If it is determined that the amount of remaining fuel is less than the threshold value D, correction for the voltage of the battery  200  is abandoned since the battery charging rate is not recovered although the second correction process is performed in Step S 221  and since the remaining fuel is insufficient, and process proceeds to Step S 224 . If it is determined that the amount of remaining fuel is more than the threshold value D, the process returns. 
   [Step S 224 ] The correction processing section  170  limits feed of power to the electric components installed in the vehicle. That is, when the correction processing section  170  determines that the battery charging rate can not be recovered by further voltage correction when the battery charging rate does not increase although the second voltage correction is performed and when the remaining fuel is insufficient, the correction processing section  170  attempts to recover the battery charging rate by limiting the feed of power to the electric components that are installed in the vehicle and consume power. At this time, the feed of power to the electric components is limited depending on external environments. Particularly, feed of power to electric components that are not necessary for driving of the vehicle is preferentially limited. 
   [Step S 225 ] The correction processing section  170  acquires interruption time of the intermittent voltage correction process. Specifically, the correction processing section  170  acquires the battery charging rate from the charging rate acquiring section  150  and acquires the interruption time stored in the predetermined time storing section  180  based on the acquired battery charging rate. 
   [Step S 226 ] The correction processing section  170  stops the voltage correction process. If the voltage correction process is not performed when Step S 226  comes around, the state that the voltage correction process is not performed remains as it is. 
   [Step S 227 ] The correction processing section  170  determines whether or not the interruption time acquired in Step S 225  elapses after the stop of the voltage correction process in Step S 226 . If it is determined that the interruption time elapses, the process proceeds to Step S 228 . 
   [Step S 228 ] The correction processing section  170  releases the stop of the voltage correction process. 
   [Step S 229 ] The correction processing section  170  performs the voltage correction process. Specifically, the correction processing section  170  performs the processes from Step S 216  to Step S 221 . 
   [Step S 230 ] The correction processing section  170  determines whether or not a predetermined time elapses after performing the voltage correction process. Specifically, the correction processing section  170  acquires the amount of remaining fuel from the remaining fuel detecting section  115 , and, based on the acquired amount of remaining fuel, acquires the predetermined time stored in the predetermined time storing section  180 . When the correction processing section  170  determines that the predetermined time elapses after performing the voltage correction process, the process proceeds to Step S 231 . 
   [Step S 231 ] The correction processing section  170  stops the voltage correction process. 
   By performing the above-described processes, the voltage to be output from the alternator  300  is corrected depending on the vehicle conditions so that the battery  200  can be early charged. 
   In addition, although the power generation amount calculating section  130  calculates the voltage to be generated by the alternator  300  in the second embodiment, the power generation amount calculation part  130  may calculate current or work to be output from the alternator  300 . In this case, a correction value to correct the current or work may be stored in the correction value storing section  160 . 
   In addition, although the voltage correction process is performed when the battery charging rate is less than the threshold value of 75% in the second embodiment, the threshold value may be varied depending on properties of vehicles or properties of running paths of vehicles, without being limited to 75%. 
   In addition, although the charging control apparatus  1  is provided independently in the second embodiment, it may be built in the alternator and operated as a battery charging apparatus. 
   [ FIG. 1 ] 
   
       
         10 : CHARGING CONTROL APPARATUS 
         21 : CAR NAVIGATOR 
         22 : RADIO 
         15 : VOLTAGE SENSOR 
         11 : BATTERY 
         16 : CURRENT SENSOR 
         17 : TEMPERATURE SENSOR 
         19 : VOLTAGE SENSOR 
         12 : ALTERNATOR 
         20 : CURRENT SENSOR 
         13 : ELECTRIC COMPONENT
 
[ FIG. 2 ]
 
         10 : CHARGING CONTROL APPARATUS 
         300 : MICROCOMPUTER
 
[ FIG. 3 ]
 
         10 : CHARGING CONTROL APPARATUS 
         41 : BATTERY CONDITION DETECTING SECTION 
         42 : ALTERNATOR CONDITION DETECTING SECTION 
         43 : ELECTRIC COMPONENT USING STATUS DETECTING SECTION 
         44 : VEHICLE RUNNING CONDITION DETECTING SECTION 
         45 : ELECTRIC COMPONENT USING STATUS PREDICTING SECTION 
         46 : VEHICLE RUNNING CONDITION PREDICTING SECTION 
         47 : GRADUAL CHANGE REQUIREMENT DETERMINING SECTION 
         48 : GRADUAL CHANGE RATE DECIDING SECTION 
         49 : SUDDEN CHANGE PERFORMING SECTION 
         50 : GRADUAL CHANGE PERFORMING SECTION
 
[ FIG. 4 ]
 
       GRADUAL CHANGE REQUIREMENT DETERMINATION PROCESS 
       S 11 : GRADUAL CHANGE REQUIREMENT DETERMINATION PROCESS AT FORMER STAGE 
       S 12 : GRADUAL CHANGE PROCESS REQUIRED? 
       S 13 : GRADUAL CHANGE REQUIREMENT DETERMINATION PROCESS AT LATTER STAGE 
       S 14 : GRADUAL CHANGE PROCESS REQUIRED? 
       S 15 : GRADUAL CHANGE PERFORMANCE PROCESS 
       S 16 : SUDDEN CHANGE PERFORMANCE PROCESS RETURN
 
[ FIG. 5 ]
 
FIRST FORMER GRADUAL CHANGE REQUIREMENT DETERMINATION PROCESS
 
       S 21 : IS ELECTRIC COMPONENT USED? 
       S 22 : GRADUAL CHANGE PROCESS REQUIRED 
       S 23 : GRADUAL CHANGE PROCESS NOT REQUIRED. RETURN
 
[ FIG. 6 ]
 
SECOND FORMER GRADUAL CHANGE REQUIREMENT DETERMINATION PROCESS
 
       S 31 : ACQUIRE POSITION OF VEHICLE. 
       S 32 : ACQUIRE WEATHER INFORMATION. 
       S 33 : ACQUIRE TIME INFORMATION. 
       S 34 : PREDICT ELECTRIC COMPONENT TO BE USED. 
       S 35 : WILL ELECTRIC COMPONENT BE USED? 
       S 36 : GRADUAL CHANGE PROCESS REQUIRED. 
       S 37 : GRADUAL CHANGE PROCESS NOT REQUIRED. RETURN
 
[ FIG. 7 ]
 
FIRST LATTER GRADUAL CHANGE REQUIREMENT DETERMINATION PROCESS
 
       S 41 : ACQUIRE VOLTAGE OR CHARGING RATE OF BATTERY. 
       S 42 : VEHICLE RUNNING CONDITION CHANGED? 
       S 43 : ACQUIRE GENERATING VOLTAGE Va 1 . 
       S 44 : ACQUIRE TARGET GENERATING VOLTAGE Va 2 . 
       S 45 : VOLTAGE OR CHARGING RATE OF BATTERY≧ PREDETERMINED VALUE? 
       S 46 : DECELERATION? 
       S 47 : GRADUAL CHANGE PROCESS NOT REQUIRED. 
       S 48 : |Va 2 -Va 1  |≧ PREDETERMINED VALUE? 
       S 49 : GRADUAL CHANGE PROCESS REQUIRED. RETURN
 
[ FIG. 8 ]
 
       BATTERY CHARGING RATE (%) 
       BATTERY VOLTAGE Vb (V)
 
[ FIG. 9 ]
 
       CORRECTION COEFFICIENT 
       LIQUID TEMPERATURE Tb (° C.)
 
[ FIG. 10 ]
 
SECOND LATTER GRADUAL CHANGE REQUIREMENT DETERMINATION PROCESS
 
       S 51 : ACQUIRE VOLTAGE OR CHARGING RATE OF BATTERY. 
       S 52 : VEHICLE RUNNING CONDITION CHANGED? 
       S 53 : ACQUIRE PRESENT POWER Pa 1 . 
       S 54 : ACQUIRE TARGET POWER Pa 2 . 
       S 55 : VOLTAGE OR CHARGING RATE OF BATTERY ≧ PREDETERMINED VALUE? 
       S 56 : DECELERATION? 
       S 57 : GRADUAL CHANGE PROCESS NOT REQUIRED. 
       S 58 : |Pa 2 -Pa 1  |≧ PREDETERMINED VALUE? 
       S 59 : GRADUAL CHANGE PROCESS REQUIRED. RETURN
 
[ FIG. 11 ]
 
THIRD LATTER GRADUAL CHANGE REQUIREMENT DETERMINATION PROCESS
 
       S 61 : ACQUIRE VOLTAGE OR CHARGING RATE OF BATTERY. 
       S 62 : ACQUIRE INFORMATION ON POSITION OF VEHICLE. 
       S 63 : PREDICT VEHICLE RUNNING CONDITION. 
       S 64 : VEHICLE RUNNING CONDITION CHANGED. 
       S 65 : ACQUIRE GENERATING VOLTAGE Va 1 . 
       S 66 : ACQUIRE TARGET GENERATING VOLTAGE Va 2 . 
       S 67 : VOLTAGE OR CHARGING RATE OF BATTERY ≧PREDETERMINED VALUE? 
       S 68 : DECELERATION? 
       S 69 : GRADUAL CHANGE PROCESS NOT REQUIRED. 
       S 70 : |Va 2 -Va 1  |≧ PREDETERMINED VALUE? 
       S 71 : GRADUAL CHANGE PROCESS REQUIRED. RETURN
 
[ FIG. 12 ]
 
FOURTH LATTER GRADUAL CHANGE REQUIREMENT DETERMINATION PROCESS
 
       S 81 : ACQUIRE VOLTAGE OR CHARGING RATE OF BATTERY. 
       S 82 : ACQUIRE INFORMATION ON POSITION OF VEHICLE, 
       S 83 : PREDICT VEHICLE RUNNING CONDITION. 
       S 84 : VEHICLE RUNNING CONDITION CHANGED. 
       S 85 : ACQUIRE PRESENT POWER Pa 1 . 
       S 86 : ACQUIRE TARGET POWER Pa 2 . 
       S 87 : VOLTAGE OR CHARGING RATE OF BATTERY ≧ PREDETERMINED VALUE? 
       S 88 : DECELERATION? 
       S 89 : GRADUAL CHANGE PROCESS NOT REQUIRED. 
       S 90 : |Pa 2 -Pa 1  |≧ PREDETERMINED VALUE? 
       S 71 : GRADUAL CHANGE PROCESS REQUIRED. RETURN
 
[ FIG. 13 ]
 
GRADUAL CHANGE RATE DECISION PROCESS
 
       S 101 : ACQUIRE VOLTAGE OR CHARGING RATE OF BATTERY. 
       S 102 : ACQUIRE INFORMATION ON VEHICLE RUNNING CONDITION. 
       S 103 : VOLTAGE OR CHARGING RATE OF BATTERY ≧ PREDETERMINED VALUE? 
       S 104 : SELECT FIRST GRADUAL CHANGE RATE TABLE. 
       S 105 : DECIDE GRADUAL CHANGE RATE. 
       S 106 : SELECT SECOND GRADUAL CHANGE RATE TABLE. 
       S 107 : DECIDE GRADUAL CHANGE RATE.
 
[ FIG. 14 ]
 
VEHICLE RUNNING CONDITION BEFORE BEING CHANGED
 
VEHICLE RUNNING CONDITION AFTER BEING CHANGED
 
GRADUAL CHANGE RATE
       POWER BEING CUT   POWER NOT BEING CUT   
     
       DECELERATION 
       IDLE 
       CONSTANT RATE 
       ACCELERATION
 
[ FIG. 15 ]
 
VEHICLE RUNNING CONDITION BEFORE BEING CHANGED
 
VEHICLE RUNNING CONDITION AFTER BEING CHANGED
 
GRADUAL CHANGE RATE
 
       DECELERATION 
       IDLE 
       CONSTANT RATE 
       ACCELERATION
 
[ FIG. 16 ]
 
SUDDEN CHANGE PROCESS
 
       S 121 : ACQUIRE TARGET GENERATING VOLTAGE Va 2 . 
       S 122 : PERFORM SUDDEN CHANGE PROCESS. 
       RETURN
 
[ FIG. 17 ]
 
GRADUAL CHANGE PROCESS
 
       S 111 : ACQUIRE GRADUAL CHANGE RATE. 
       S 121 : ACQUIRE TARGET GENERATING VOLTAGE Va 2 . 
       S 122 : PERFORM GRADUAL CHANGE PROCESS. 
       RETURN
 
[ FIG. 18 ]
 
         1 : CHARGING CONTROL APPARATUS 
         2 : BATTERY 
         3 : SENSOR 
         1   a : VEHICLE CONDITION DETECTING SECTION 
         1   b : TARGET ELECTRIC QUANTITY DETERMINING SECTION 
         1   d : CORRECTION VALUE ACQUIRING SECTION 
         1   e : TARGET ELECTRIC QUANTITY CORRECTING SECTION 
         1   c : CORRECTION VALUE STORING SECTION 
         4 : ELECTRIC GENERATOR
 
[ FIG. 19 ]
 
         100 : MASTER ECLT 
         500 : NAVIGATOR 
         410 : COMMUNICATION BUS 
         410 : POWER LINE
 
[ FIG. 20 ]
 
         400 : BUS 
         100 : MASTER ECU 
         101 : MECRO COMPUTER
 
[ FIG. 21 ]
 
         100 : MASTER ECU 
         110 : VEHICLE CONDITION DETECTING SECTION 
         111 : BATTERY CONDITION DETECTING SECTION 
         112 : ELECTRIC COMPONENT USING STATUS DETECTING 
       SECTION 
         113 : VEHICLE SITUATION DETECTING SECTION 
         114 : EXTERNAL ENVIRONMENT DETECTING SECTION 
         115 : REMAINING FUEL DETECTING SECTION 
         130 : POWER GENERATION AMOUNT CALCULATING SECTION 
         140 : CHARGING RATE STORING SECTION 
         150 : CHARGING RATE ACQUIRING SECTION 
         170 : CORRECTION PROCESSING SECTION 
         120 : TARGET VOLTAGE STORING SECTION 
         180 : PREDETERMINED TIME STORING SECTION 
         160 : CORRECTION VALUE STORING SECTION
 
[ FIG. 22 ]
 
         141 : VOLTAGE-CHARGING RATE GRAPH 
       BATTERY CHARGING RATE [%] 
       OPEN VOLTAGE [v]
 
[ FIG. 23 ]
 
 142 : LIQUID TEMPERATURE-CORRECTION VALUE GRAPH
 
       CORRECTION VALUE 
       LIQUID TEMPERATURE [° C.]
 
[ FIG. 24 ]
 
 161 : CHARGING RATE -CORRECTION VALUE GRAPH
 
       CORRECTION VALUE 
       BATTERY CHARGING RATE [%]
 
[ FIG. 25 ]
 
 162 : LIQUID TEMPERATURE-CORRECTION VALUE GRAPH
 
       CORRECTION VALUE 
       LIQUID TEMPERATURE [° C.]
 
[ FIG. 26 ]
 
 163 : CURRENT-CORRECTION VALUE GRAPH
 
       CORRECTION VALUE 
       CONSUMPTION CURRENT [A]
 
[ FIG. 27 ]
 
 181 : CHARGING RATE-DETERMINATION TIME GRAPH
 
       DETERMINATION TIME 
       BATTERY CHARGING RATE [%]
 
[ FIG. 28 ]
 
 182 : CHARGING RATE-INTERRUPTION TIME GRAPH
 
       INTERRUPTION TIME 
       BATTERY CHARGING RATE [%]
 
[ FIG. 29 ]
 
 183 : REMAINING FUEL-ELAPSE TIME GRAPH
 
       ELAPSE TIME 
       REMAINING FUEL [L]
 
[ FIG. 30 ]
 
 164 : CHARGING BATE-CORRECTION TABLE
 
       BATTERY CHARGING RATE [%] 
       CORRECTION VALUE
 
[ FIG. 31 ]
 
 165 : VEHICLE SITUATION-CORRECTION TABLE
 
       VEHICLE SITUATION
       ACCELERATION   IDLE   CONSTANT RATE   DECELERATION OR RACING
 
CORRECTION VALUE [V]
 
[ FIG. 32 ]
 
START
   
     
       S 211 : DETECT VEHICLE CONDITION. 
       S 212 : CALCULATE VOLTAGE TO BE GENERATED BY ALTERNATOR. 
       S 213 : CORRECTION PROCESS REQUIRED? 
       S 214 : DOES REMAINING FUEL AMOUNT EXCEED A? 
       S 215 : IS CHARGING RATE LESS THAN B? 
       S 216 : INSTRUCT ALTERNATOR TO OUTPUT VOLTAGE. 
       S 218 : DETERMINATION TIME ELAPSED? 
       S 219 : NO INCREASE OF VOLTAGE? 
       S 220 : CALCULATE VOLTAGE CORRECTION VALUE. 
       S 221 : INSTRUCT ALTERNATOR TO OUTPUT VOLTAGE. 
       S 225 : ACQUIRE INTERRUPTION TIME. 
       S 226 : STOP VOLTAGE CORRECTION. 
       S 227 : INTERRUPTION TIME ELAPSED? 
       S 228 : RELEASE VOLTAGE CORRECTION STOP 
       S 229 : PERFORM VOLTAGE CORRECTION PROCESS. 
       S 230 : PREDETERMINED TIME ELAPSED? 
       S 231 : STOP VOLTAGE CORRECTION PROCESS. 
       S 222 : Is CHARGING RATE LESS THAN C? 
       S 223 : IS REMAINING FUEL AMOUNT LESS THAN D? 
       S 224 : LIMET FEED OF POWER. 
       RETURN