Patent Publication Number: US-10330710-B2

Title: Apparatus for managing power of vehicle and method of controlling the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to and the benefit of Korean Patent Application No. 10-2017-0077880, filed on Jun. 20, 2017, which is incorporated herein by reference in its entirety. 
     FIELD 
     The present disclosure relates to a power management apparatus and a method of controlling the same, for determining whether a power system of a vehicle is abnormal. 
     BACKGROUND 
     The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
     In general, a fuse box is installed in a vehicle. The fuse box normally contains a fuse to protect a circuit from power supplied to various electronic devices. Recently, a smart junction box (SJB) is prevalent as a multifunctional fuse box which contains a microcontroller unit (MCU) controlling an operational time of various relay circuits and other electronic devices, besides a general purpose of the fuse box. 
       FIG. 1  is a diagram illustrating an example of a general smart junction box  100 . 
     Referring to  FIG. 1 , the smart junction box  100  may include an MCU  110  which controls in supplying or shutting off power to various loads in a vehicle. It triggers a relay and an intelligent power switch (IPS) with power supplied from a battery  210  based on a control signal received through a communication unit  220  and a state of a vehicle switch  230 . In addition, the smart junction box  100  may normally include a fuse switch  120  that is turned on when a vehicle is delivered to a customer. As a result, the MCU  110  may control power supplied to the vehicle using different methods according to a state of the fuse switch  120 , which will be described with reference to  FIG. 2 . 
       FIG. 2  is a flowchart illustrating an example of a procedure of managing vehicle power in a general smart junction box. 
     Referring to  FIG. 2 , as external switch input is generated or controller area network (CAN) communication is activated, the smart junction box may supply power to various load systems in a vehicle (S 201 ). When a sleep mode condition is satisfied (e.g., CAN communication enters a sleep mode) after power is supplied (S 202 ), the smart junction box may enter a sleep mode (S 203 ) and perform an operation for shutting off dark current. 
     The operation for shutting off dark current may be varied according to a fuse switch state (S 204 ). In detail, when the fuse switch is turned on at time of delivery to a customer, if a timer is started and a predetermined time (e.g., 20 minutes) elapses (S 205 ), a lamp load is first shut off (S 206 ). However, when a longer time (e.g., 12 hours) elapses (S 207 ), a body electrical load may be shut off (S 208 ). When the body electrical load is shut off, the MCU is powered off (S 209 ) and is maintained in a corresponding state until a preset release condition is satisfied (S 210 ). Here, when a lock signal is received through a remote controller such as a smart key after the timer is started, a short time (e.g., 5 seconds) elapses and, then, a load may be shut off. In addition, the preset release condition may be such as a change in exchange switch input and/or CAN communication activation. 
     When a fuse switch state is off, if a predetermined time (e.g., 5 minutes) elapses after the timer is started (S 211 ), all loads may be shut off at one time (S 222 ). 
     However, in the aforementioned power management apparatus, only some loads (i.e., lamp load and body load) are structurally shut off by a smart junction box. Also, a dark current blocking function is activated only per management policies of a vehicle manufacturer. As a result, it may be difficult to satisfy driver requirements. 
     In addition, determining whether a power system of a driving vehicle is abnormal is conducted for each load and, thus, the number of resistors required by a circuit for detecting and monitoring abnormal power may increase, thereby increasing manufacturing costs as well. 
     SUMMARY 
     The present disclosure provides a power management apparatus of a vehicle and a method of controlling the same, for determining whether a power system of a vehicle is abnormal. 
     In particular, the present disclosure provides a power management apparatus of a vehicle and a method of controlling the same which may contribute in enhancing product reliability and reducing manufacturing costs. This can be achieved by a resistor circuit and error correction logic that is designed to collectively monitor a battery voltage supplied to a plurality of loads. 
     In one form of the present disclosure, a power management apparatus of a vehicle includes a battery, a battery sensor configured to acquire voltage information of the battery, and a controller configured to receive the voltage information of the battery, to compare a second voltage and a third voltage with preset reference information, and to determine whether power is abnormal, wherein a first voltage is measured by the controller, the second voltage is adjusted by converting the first voltage into a digital signal, and the third voltage is measured by the battery sensor. 
     In another form of the present disclosure, a method of controlling a power management apparatus for a vehicle includes calculating a second voltage that is adjusted by converting a first voltage into a digital signal, wherein the first voltage is measured by a controller and the controller includes a monitoring circuit and a microcontroller unit (MCU), measuring a third voltage from a battery sensor, comparing the second voltage and the third voltage with preset reference information, and determining whether power is abnormal. 
     Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which: 
         FIG. 1  is a diagram illustrating an example of a general smart junction box; 
         FIG. 2  is a flowchart illustrating an example of a procedure of managing vehicle power in a general smart junction box; 
         FIG. 3  is a diagram illustrating configuration of a power management system; 
         FIGS. 4A and 4B  are diagrams illustrating an example of monitoring circuits; 
         FIGS. 5A and 5B  are diagrams illustrating an example of calculation of a correction constant and use of correction logic of a monitoring circuit; 
         FIG. 6  is a diagram showing an example of preset reference information configured in the form of a table; 
         FIG. 7  is a diagram illustrating an example of the logic for determining whether a power system of a vehicle is abnormal during driving; and 
         FIG. 8  is a diagram showing an example of comparison of the reference information and the real-time voltage information of a vehicle. 
     
    
    
     The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
     DETAILED DESCRIPTION 
     The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. 
     Here, the suffixes “module” and “unit” of elements herein are used for convenience of description and thus can be used interchangeably and do not have any distinguishable meanings or functions. 
     In the following description of the at least one form, a detailed description of known functions and configurations incorporated herein will be omitted for the purpose of clarity and for brevity. The features of the present disclosure will be more clearly understood from the accompanying drawings and should not be limited by the accompanying drawings, and all changes, equivalents, and substitutes that do not depart from the spirit and technical scope of the present disclosure are encompassed in the present disclosure. 
     To determine whether a power system is abnormal and to warn a user during driving, a form of the present disclosure proposes a resistor circuit and error correction logic for collectively monitoring a battery voltage applied to a plurality of loads. 
     A power management system  300  of a vehicle for the above proposal will be described with reference to  FIG. 3 . 
       FIG. 3  is a diagram illustrating configuration of the power management system  300  in some forms of the present disclosure. 
     Referring to  FIG. 3 , the power management system  300  in some forms of the present disclosure may include a battery  310 , a battery sensor  320 , and a controller  330 . 
     The battery  310  may supply power to various load systems in the vehicle and the battery sensor  320  installed in the battery  310  may detect power supplied by the battery  310 . 
     The controller  330  may receive battery voltage information detected by the battery sensor  320  through a network in the vehicle. 
     In some forms of the present disclosure, a communication method for embodying a network system may be wired communication applicable to vehicles, for example, controller area network (CAN), local interconnect network (LIN), Flexray, Ethernet, and so on, but is not limited thereto. 
     The controller  330  may be an integrated control unit (ICU) or may be embodied as an integrated gateway &amp; power control module (IGPM) but is not limited thereto. 
     The controller  330  may include a monitoring circuit  340  and a microcontroller unit (MCU)  350 . 
     The monitoring circuit  340  may drop a voltage applied from the battery  310  and output the dropped voltage to the MCU  350 , and the MCU  350  may convert a voltage applied from the monitoring circuit  340  into a digital signal and compare a voltage with a correction constant applied thereto with reference information to determine whether a power system is abnormal. 
     Here, the correction constant may be defined as a value calculated in consideration of an error rate of a plurality of resistors included in the monitoring circuit  340 , which will be described below with reference to  FIGS. 5A and 5B . 
     The reference information may be configured in the form of a table including a plurality of items defined as preset data, which will be described below with reference to  FIG. 6 . 
     The MCU  350  may include a converter  351 , a correction processor  352 , a receiver  353 , a memory unit  354 , a determiner  355 , and a transmitter  356 . 
     The converter  351  may include an analog/digital converter (ADC) for converting a voltage (hereinafter, referred to as a “first voltage”) output from the monitoring circuit  340  into a digital signal. 
     The correction processor  352  may apply the correction constant to a voltage obtained by converting the first voltage into a digital signal to calculate a voltage (hereinafter, referred to as a “second voltage”) with high reliability. 
     The receiver  353  may receive a battery voltage (hereinafter, referred to as a “third voltage”) detected by the battery sensor  320  through a network. 
     The memory unit  354  may generate preset reference information and a memory space for storing the reference information, and an applicable apparatus may include an electrically erasable programmable read-only memory (EEPROM) or the like but is not limited thereto. 
     The determiner  355  may compare the second voltage corresponding to the third voltage with reference information to determine whether a power system including components to the controller  330  from the battery  310  is abnormal and the transmitter  356  may transmit a warning message to a display device in the vehicle upon determining that the power system is abnormal. 
     The controller  330  may include an intelligent power switch (IPS) that is operated to supply or shut off power supplied from the battery  310  to various loads in the vehicle. 
     Load  1  and load  2  may include a headlamp load, a vehicle electrical load, a multimedia load, or the like but this is purely exemplary and the present disclosure is not limited thereto. 
     Hereinafter, configuration of monitoring circuits  340   a  and  340   b  will be described in more detail based on the aforementioned power management system  300 . 
       FIGS. 4A and 4B  are diagrams illustrating an example of monitoring circuits  340   a  and  340   b  in some forms of the present disclosure. 
     The monitoring circuits  340   a  and  340   b  may drop a voltage applied from the battery  310  and output the dropped voltage to MCUs  350   a  and  350   b , and the MCUs  350   a  and  350   b  may monitor the voltage output from the monitoring circuits  340   a  and  340   b  to determine whether a power system including components to the controller from the battery  310  is abnormal. 
     First, referring to  FIG. 4A , the monitoring circuit  340   a  in some forms of the present disclosure may independently include a plurality of resistors R 1  and R 3  that are connected in series to load  1  among a plurality of loads and a plurality of resistors R 2  and R 4  that are connected in series to load  2 . 
     Referring to  FIG. 4B , the monitoring circuit  340   b  in some forms of the present disclosure may include a plurality of resistors R 1  and R 2  that are connected in parallel to a plurality of loads and a common node Nc of a battery, and a resistor R 3  connected in series to a plurality of resistors that are connected in parallel. 
     When the monitoring circuit  340   b  is used, the MCU  350   b  measure one voltage V 1  output by the monitoring circuit  340   b  to determine whether power is abnormal and, thus, a battery voltage supplied to a plurality of loads is collectively monitored and some of a plurality of resistors included in a circuit are omitted, thereby reducing manufacturing costs. 
     A plurality of resistors included in a monitoring circuit has an error rate and, thus, the correction constant may be applied to calculate a voltage with high reliability. 
     Hereinafter, a procedure of calculating a correction constant will be described in more detail. 
     In the following description including  FIGS. 5A and 5B  of the specification, for convenience of description, it is assumed that a controller of a vehicle is an integrated gateway &amp; power control module (IGPM) of the controller. However, this is purely exemplary and the present disclosure is not limited thereto. 
       FIGS. 5A and 5B  are diagrams illustrating an example of calculation of a correction constant and use of correction logic of a monitoring circuit. 
     In  FIG. 5A , an IGPM sample with an ideal resistor without an error rate may be applied. 
     Referring to  FIG. 5A , when a reference voltage V input  with predetermined amplitude is applied to a monitoring circuit, a first voltage V 1   _   ref  measured by the MCU may be calculated based on Ohm&#39;s law according to the following equation. 
     
       
         
           
             
               
                 
                   
                     V 
                     
                       1 
                       ⁢ 
                       
                         _ 
                         ⁢ 
                         ref 
                       
                     
                   
                   = 
                   
                     
                       
                         ( 
                         
                           
                             R 
                             3 
                           
                           
                             
                               
                                 
                                   R 
                                   1 
                                 
                                  
                               
                               ⁢ 
                               
                                 R 
                                 2 
                               
                             
                             + 
                             
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                       × 
                       
                         V 
                         input 
                       
                     
                     = 
                     
                       R 
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                         V 
                         input 
                       
                     
                   
                 
               
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     1 
                   
                   ] 
                 
               
             
           
         
       
     
     In  FIG. 5B , an IGPM sample with an actual resistor with an error rate may be applied. 
     Referring to  FIG. 5B , when a reference voltage V input  with predetermined amplitude is applied to a monitoring circuit, a first voltage V 1   _   car  measured by an MCU may be calculated based on Ohm&#39;s law according to the following equation. 
     In this case, the monitoring circuit may include a plurality of resistors R 1  and R 2  that are connected in parallel to a plurality of loads and a common node of a battery, a resistor R 3  connected in series to a plurality of resistors that are connected in parallel, and error resistors ΔR 1 , ΔR 2  and ΔR 3 . 
     
       
         
           
             
               
                 
                   
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                   [ 
                   
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     A correction constant σ may be defined as the first voltage V 1   _   ref  of the IGPM sample with an ideal resistor applied thereto with respect to the first voltage V 1   _   car  of the IGPM sample with an actual resistor applied thereto based on the same voltage V input  and may be calculated according to the following equation. 
     
       
         
           
             
               
                 
                   σ 
                   = 
                   
                     
                       R 
                       
                         R 
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                           ⁢ 
                           
                               
                           
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                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
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                     3 
                   
                   ] 
                 
               
             
           
         
       
     
     In this case, the correction constant σ may represent the same or different features for each produced IGPM and a memory unit of a controller may pre-store the calculated correction constant σ. 
     The correction constant σ calculated through the aforementioned procedure may be applied to the voltage V 2   _   car  obtained by converting the first voltage measured in a condition of applying the IGPM with an actual resistor to a vehicle into a digital signal so as to reduce error and, thus, the second voltage V 2   _   ref  with high reliability may be calculated. 
     The second voltage V 2   _   ref  calculated via error correction logic may be calculated according to the following equation.
 
 V   2   _   ref   =σ×V   2   _   car   [Equation 4]
 
     The third voltage measured by the battery sensor  320  of the vehicle during driving may correspond to the second voltage calculated by applying a correction constant to a voltage obtained by converting a voltage measured by the controller  330  into a digital signal. 
     Hereinafter, a procedure of generating reference information as a comparison target to determine whether power is abnormal will be described in more detail. 
       FIG. 6  is a diagram showing an example of preset reference information  600  configured in the form of a table. 
     The preset reference information  600  may be formed by configuring a second reference voltage  610  corrected by converting a first reference voltage measured by a controller into a digital signal and a third reference voltage  620  measured by a battery sensor, in the form of a table. 
     The second reference voltage may be a value obtained by converting the first reference voltage measured by an IGPM including an ideal resistor without an error rate into a digital signal. When the reference information is used, even if a resistor with a high error rate is used in the monitoring circuit  340 , a voltage with high reliability may be provided, thereby enhancing product reliability and reducing manufacturing costs. 
     The third reference voltage measured by the battery sensor  320  may corresponds to the second reference voltage calculated by the controller  330 . 
     In this case, the second reference voltage may be defined as a voltage converted into a digital signal by an analog/digital converter and may be stored in the form of an integer. 
     Battery voltage variation may be guided via various conditions after a vehicle is produced and, thus, the memory unit  354  of the controller  330  may generate a plurality of data of the second reference voltage and/or the third reference voltage. 
     The table may include a plurality of items  630  and  640 , each of the plurality of items may include a pair of the second reference voltage and the third reference voltage that correspond to each other, and the pair of the second reference voltage and the third reference voltage, included in each of the plurality of items, may have different values. 
     For example, a first item  630  of the plurality of items may include a pair of a third reference voltage of 13.6 V and a second reference voltage of 531 V corresponding thereto and the second reference voltage and the third reference voltage, included in each of the first item  630  and a second item  640 , may have different voltages. However, this is purely exemplary and it would be obvious to one of ordinary skill in the art that a detailed range of the second reference voltage and the third reference voltage is not limited thereto. 
     Hereinafter, logic for determining whether a power system is abnormal based on the aforementioned voltage measured by the battery sensor  320  during driving, the voltage calculated by the controller  330 , and the preset reference information will be described with reference to  FIGS. 7 and 8 . 
       FIG. 7  is a diagram illustrating an example of the logic for determining whether a power system of a vehicle is abnormal during driving. 
     Referring to  FIG. 7 , first, the controller  330  may calculate a second voltage from the battery  310  of a driving vehicle (S 710 ) and receive a third voltage from a battery sensor  320  (S 720 ). 
     The converter  351  of the controller  330  may measure a first voltage output from the monitoring circuit  340  (S 711 ) and an analog/digital converter (ADC) may convert the first voltage into a digital signal (S 712 ). 
     The correction processor  352  may multiply the voltage converted into the digital by a preset correction constant (S 713 ) to calculate the second voltage (S 714 ). 
     The receiver  353  may receive a third voltage of a battery, detected by the battery sensor  320 , through a network (S 721 ). 
     Upon receiving voltage information of the driving vehicle via operations S 710  and S 720 , the controller  330  may compare the voltage information with preset reference information (S 730 ). 
     A procedure of comparing and determining real-time voltage information of a driving vehicle and preset reference information will be described in more detail with reference to  FIG. 8 . 
       FIG. 8  is a diagram showing an example of comparison of the reference information and the real-time voltage information of a vehicle. 
     Referring to  FIG. 8 , a second reference voltage matched with a third reference voltage corresponding to a received third voltage may be compared with a second voltage to determine whether power is abnormal. 
     For example, when a third voltage of the real-time voltage information of a vehicle, received during driving, is 14.2 V, the second reference voltage corresponding to the third reference voltage corresponding to 14.2 V from the preset reference information may be retrieved and compared with the second voltage. 
     Referring back to  FIG. 7 , whether error between the second reference information and the reference information and the second voltage received by a driving vehicle is greater than a preset error allowable range may be determined (S 740 ). 
     When the error is greater than the preset error allowable range, a warning message may be transmitted to a display device in the vehicle (S 760 ). 
     The disclosure can also be embodied as computer readable code on a computer readable recording medium. The computer readable recording medium is any data storage device that can store data which can be thereafter read by a computer system. Examples of the computer readable recording medium include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, carrier wave such as transmission via the Internet, etc. 
     In some forms of the present disclosure, the following effects may be obtained. 
     An issue that may arise due to abnormality of a power system of a vehicle may be pre-monitored and notified to a user, thereby reducing the number of accidents which may be caused during driving. 
     In addition, a resistor circuit and error correction logic for collectively monitoring a battery voltage applied to a plurality of loads may enhance product reliability and reduce manufacturing costs. 
     It will be appreciated by persons skilled in the art that that the effects that could be achieved with the present disclosure are not limited to what has been particularly described hereinabove and other advantages of the present disclosure will be more clearly understood from the detailed description taken in conjunction with the accompanying drawings. 
     The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the substance of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.