Electric power supply system between vehicle and house

An electric bower supply system includes a power supply controlling element (62) configured to switch a plug-out power supply which supplies electric power (75) from a fuel cell (20) or a battery (21) to a house (70) and a plug-in power supply which supplies electric power from a commercial power source (75) disposed in the house (70) to a fuel cell vehicle (1a) on the basis of a vehicular power state of the fuel cell (20) and the battery (21) detected by a vehicular power state detecting element (61) and a household power state of the commercial power source (75) detected by a household power state detecting element (81) when a receptacle (10) of the fuel cell vehicle (1a) and an outlet (71) of the commercial power source (75) have been connected by a power cable (100).

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electric power supply system which supplies electric power between a vehicle provided with a vehicular power source and a house provided with a household power source.

2. Description of the Related Art

Hitherto, there has been disclosed a system performing a so-called plug-in power supply which supplies electric power from a commercial power source disposed in a house to a vehicle via a power cable connected between an external power source connector disposed in the vehicle and an outlet of the commercial power source (for example, refer to Japanese Patent Laid-open No. 2008-61432).

According to the plug-in power supply, a battery provided in a hybrid electric vehicle or an electric automobile which uses a motor as a driving source can be charged with the electric power of the commercial power source supplied from the house.

Moreover, according to Japanese Patent Laid-open No. 2008-61432, in order to prevent the electric power from being stolen from the outlet disposed in the house, the system is configured to perform an authorization between the vehicle and a bower supply portion in the house and the plug-in power supply from the house to the vehicle is permitted only when the authorization is valid.

There has also been disclosed a system performing a so-called plug-out power supply which generates an alternating-current power same as the commercial power source and outputs it to an outlet disposed in the vehicle with the same shape as the outlet of the commercial power source (for example, refer to Japanese Patent Laid-open No. 2006-20445). As above-mentioned, one system which performs the plug-in power supply and another system which performs the plug-out power supply have been disclosed, however, a combination of the two systems has not been proposed yet.

SUMMARY OF THE INVENTION

The present invention has been accomplished in view of the aforementioned problems, and it is therefore an object of the present invention to provide an electric power supply system which supplies electric power between a vehicle provided with a vehicular power source and a house provided with a household power source in both directions according to a plug-in power supply and a plug-out power supply by effectively utilizing electric power supplied from the vehicular power source in the vehicle and the household power source in the house, while appropriately adjusting a temperature of the vehicular power source such as a fuel cell or a battery.

To attain an object described above, there is provided an electric power supply system between a vehicle and a house comprising: a power source connecting element configured to have a detachable connection between a vehicular power source disposed in the vehicle and a household power source disposed in the house for an electric power supply in both directions; a vehicular power state detecting element configured to detect a vehicular power state; a household power state detecting element configured to detect a household power state; and a power supply controlling element configured to switch a plug-out power supply which supplies electric power from the vehicular power source to the house and a plug-in power supply which supplies electric power from the household power source to the vehicle on the basis of the vehicular power state detected by the vehicular power state detecting element and the household power state detected by the household power state detecting element when the vehicular power source disposed in the vehicle and the household power source disposed in the house have been connected by the power source connecting element for electric power supply in both directions.

According to the present invention, the plug-out power supply which supplies electric power from the vehicular power source to the house and the plug-in power supply which supplies electric power from the household power source to the vehicle are switched by the power supply controlling element according to the vehicular power state and the household power state.

By switching the slug-out power supply and the plug-in power supply, the vehicular power source and the household power source can compensate each other to make effective use of the electric power supplied therefrom. Moreover, adjusting appropriately the temperature of the vehicular power source can contribute to stabilizing the performance of the vehicular power source.

In the present invention, the vehicular power source is a fuel cell, and the power supply controlling element performs the plug-out power supply to supply a generated power from the fuel cell to the house when a warm-up operation which increases a temperature of the fuel cell according to the power generation of the fuel cell is detected by the vehicular power state detecting element to be on operation.

Conventionally, electric power is needed to perform the warm-up operation for the fuel cell and the electric power is generated in the warm-up operation. Thus, if the generated electric power cannot be consumed by electric accessory devices disposed in the vehicle, it is necessary to dispose a resistor with a greater rated power for converting the generated electric power to heat in the vehicle in order to consume the electric power. As a result thereof, the electric power generated by the fuel cell is consumed in vain, and the provision of the resistor with a greater rated power would increase component-mounting space and component cost.

Thus, the power supply controlling element supplies the generated electric power from the fuel cell to the house to be consumed in the house. According thereto, the generated electric power from the fuel cell can be utilized to operate electric loads in the house such as electric home appliances or can be sold to an electric power company. Thereby, the generated electric power from the fuel cell can be effectively utilized. Moreover, by replacing a resistor with a greater rated power for consuming the generated electric power from the fuel cell with another resistor with a smaller rated power in the vehicle, it is expected to reduce the component-mounting space and the component cost.

In the present invention, the vehicle is an electric vehicle provided with a motor to drive a driving wheel; the vehicular power source is an electric accumulator; and the power supply controlling element performs the plug-out power supply to supply a discharged power from the electric accumulator to the house when a warm-up operation which increases a temperature of the electric accumulator according to the power discharging of the electric accumulator is detected to be on operation by the vehicular power state detecting element.

According to the present invention, electric power is needed to perform the warm-up operation for the electric accumulator and the electric power is discharged in the warm-up operation. Thus, if the discharged electric power cannot be consumed by the electric accessory devices disposed in the vehicle, it is necessary to dispose a resistor with a greater rated cower for converting the discharged electric power to heat in the vehicle in order to consume the electric power. As a result thereof, the electric power discharged by the electric accumulator is consumed in vain, and the provision of the resistor with a greater rated power would increase component-mounting space and component cost.

Thus, the power supply controlling element supplies the discharged electric power from the electric accumulator to the house to be consumed in the house. According thereto, the discharged electric power from the electric accumulator can be utilized to operate electric loads in the house such as electric home appliances or can be sold to an electric power company. Thereby, the discharged electric power from the electric accumulator can be effectively utilized. Moreover, by replacing a resistor with a greater rated power for consuming the discharged electric power from the electric accumulator with another resistor with a smaller rated power in the vehicle, it is expected to reduce the component-mounting space and the component cost.

In the present invention, the vehicle is a hybrid electric vehicle provided with a motor and an engine to drive a driving wheel; the vehicular power source is an electric accumulator; and the power supply controlling element performs the plug-out power supply to supply a discharged power from the electric accumulator or a generated power from the motor which is driven by the engine to serve as a power generator to the house when a first warm-up operation which increases a temperature of the electric accumulator according to the power discharging of the electric accumulator or a second warm-up operation which increases the temperature of the electric accumulator according to the power charging by the generated power from the motor is detected to be on operation by the vehicular power state detecting element.

According to the present invention, electric power is needed to perform the first warm-up operation or the second warm-up operation for the fuel cell and the electric power is generated according to the discharging of electric power in the first warm-up operation or the generation of electric power in the second warm-up operation. Thus, if the generated electric power cannot be consumed by electric accessory devices disposed in the vehicle, it is necessary to dispose a resistor with a greater rated power for converting the generated electric power to heat in the vehicle to consume the electric power. As a result thereof, the electric power discharged from the electric accumulator and the electric power generated from the motor are consumed in vain, and the provision of the resistor with a greater rated power would increase the component-mounting space and the component cost.

Thus, the power supply controlling element supplies the electric power discharged from the electric accumulator and the electric power generated from the house to be consumed in the house. According thereto, the electric power discharged from the electric accumulator and the electric power generated from the motor can be utilized to operate electric loads in the house such as electric home appliances or can be sold to an electric power company. Thereby, the electric power discharged from the electric accumulator and the electric power generated from the motor can be effectively utilized. Moreover, by replacing a resistor with a greater rated power for consuming the generated electric power from the fuel cell with another resistor with a smaller rated power in the vehicle, it is expected to reduce the component-mounting space and the component cost.

In the present invention, the power supply controlling element performs the plug-out power supply to supply the electric power from the vehicular power source to the house to compensate the shortage of output power from the household power source when the voltage of the output power from the household power source is detected to be equal to or lower than a predefined level by the household power state detecting element.

According to the present invention, when the output voltage a household power source is decreased due to increment of consumed electric power or electric power failure in the house, the shortage of output power from the household power source can be compensated by performing the plug-out power supply.

In the present invention, the vehicle is provided with a shift position detecting element configured to determine whether or not a shift lever is set at a position of parking, a motor configured to drive a driving wheel, and a switching element configured to switch on and off the electric power supply to the motor; and the electric power supply system further includes a power connection permitting element configured to permit the connection between the vehicular power source disposed in the vehicle and the household power source disposed in the house for the electric power supply in both directions by the power source connecting element on condition that the shift lever is detected to be set at the position of parking by the shift position detecting element and the electric power supply to the motor is switched off by the switching element.

According to the present invention, when the shift lever of the vehicle is set at the position of parking and the electric power supply to the motor is switched off by the switching element, it is impossible to run the vehicle at the moment. According to the present invention, the connection between the vehicular power source disposed in the vehicle and the household power source disposed in the house for the electric power supply in both directions by the power source connecting element is permitted by the power connection permitting element on condition that the vehicle is unable to be run. Thereby, the vehicle can be undoubtedly prevented from being run by mistake when the vehicle and the house are connected by the power source connecting element.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, an embodiment of the present invention will be described in detail with reference toFIG. 1toFIG. 7.FIG. 1illustrates an overall configuration of an electric power supply system between a vehicle and a house when the present invention is applied to a fuel cell vehicle.

Referring toFIG. 1, the fuel cell vehicle1ais provided with a vehicular power source including a fuel cell20, a battery (for example, a lithium ion battery) and a capacitor23. Electric power from the vehicular power source is supplied to a motor41which is connected with a driving wheel (not shown) as a driving power through a PDU (Power Drive Unit)40.

The fuel cell vehicle1ais further provided with a DC/DC converter30connected between the PDU40and a location aside the fuel cell20and the capacitor23, a DC/DC converter31connected between the battery21and a location between the DC/DC converter30and the PDU40; a PDU42connected between an electric accessory device43and a location between the DC/DC converter31and the battery21, a motor switch35(corresponding to a switching element of the present invention) for switching electric power supply to the PDU40, a plug receptacle10(corresponding to a power source connecting element of the present invention), a movable cover10afor exposing or covering the plug receptacle10, and a controller60afor controlling electric power supply between the fuel cell vehicle1aand the house70. Herein, the electric accessory device43may be, for example, a reactant gas supplying device for supplying reactant gases to the fuel cell20, an air conditioner, or a water pump for circulating coolants in a coolant circulation circuit to heat or cool the fuel cell20.

The fuel cell20is provided with a fuel cell sensor50for detecting a state of the fuel cell20. The state of the fuel cell20includes, for example, a temperature, a terminal voltage, an output current, and a supply pressure of reactant gases (hydrogen and air in the present embodiment) for the fuel cell20.

The battery21is provided with a battery sensor52for detecting a temperature, a terminal voltage, an output current and the like for the battery21. Similarly, the capacitor23is provided with a capacitor sensor51for detecting a temperature, a terminal voltage, an output current and the like for the capacitor23.

The controller60ais an electronic unit composed of a microcomputer (not shown) and the like. By causing microcomputer to execute a control program configured to supply electric power between the fuel cell vehicle1aand the house70, the controller60afunctions as a vehicular power state detecting element61a, a power supply controlling element62a, a PLC (Power Line Carrier, Power Line Communication) transmitting element63, and a power connection permitting element64.

Detection signals FC_s on the temperature, the terminal voltage, the output current, the supply pressure of reactant gases and the like detected by the fuel cell sensor50for the fuel cell20, detection signals UC_s on the temperature, the terminal voltage, the output current and the like detected by the capacitor sensor51for the capacitor23, and detection signals BT_s on the temperature, the terminal voltage, the output current and the like detected by the battery sensor52for the battery21are input into the controller60a.

The operations of the DC/DC converters30and31, the PDU42, the motor switch35, the movable cover10a,the reactant gas supplying device, the water pump and the like are controlled according to control signals output from the controller60a, respectively.

The vehicular power state detecting element61adetects the temperature, the terminal voltage, the output current, the generated power source and the like for the fuel cell20according to the detection signals FC_s output from the fuel cell sensor50; detects the temperature, the terminal voltage, the output current, SOC (State of Charge: the percentage of residual charge amount when the full-charged amount is denoted as 100%) and the like for the capacitor23according to the detection signals UC_s output from the capacitor sensor51; and detects the temperature, the terminal voltage, the output current, the SOC and the like for the battery21according to the detection signals BT_s output from the battery sensor52. The power supply controlling element62a, on the basis of the state of the fuel cell20and the battery21detected by the vehicular power state detecting element61aand the state of a commercial power source in the house70detected by a household power state detecting element81(to be described hereinafter), switches a plug-in power supply which supplies electric power from the house70to the fuel cell vehicle1avia a power cable100and a plug-out power supply which supplies electric power from the fuel cell vehicle1ato the house70via the power cable100.

The PLC (Power Line Communication) transmitting element63performs communications by using electric power lines including the power cable100to carry data signals between the controller60adisposed in the fuel cell vehicle1aand a controller80(to be described hereinafter) disposed in the house70.

On condition that a shift lever (not shown) is determined to be at the position of parking P according to detection signals Sh_s output from a shift position sensor (not shown) configured to detect a position of the shift lever, the power connection permitting element64opens the movable cover10aby turning off the motor switch35(disconnected state) when an open operation is performed by a driver on the movable cover10acovering the plug receptacle10.

The above-mentioned controller80which is disposed in the house70is an electronic unit composed of a microcomputer (not shown) and the like. By causing the microcomputer to execute a control program configured to supply electric power between the fuel cell vehicle1aand the house70, the controller80functions as the above-mentioned household power state detecting element81and a PLC transmitting element82.

The controller80is connected with the commercial power source75through a switch box74having a power usage meter72and a power selling meter73. The switch box74distributes electric power supplied from the commercial power source75to power outlets disposed in the house70. The switch box74corresponds to a household power source provided in the house in the present invention. A connection portion between the switch box74and the commercial power source75is connected with a power outlet71by a power line85.

The household power state detecting element81detects the state of the commercial power source75in the house70according to detection signals Pi_s on the voltage, the power usage and one like of the commercial power source75output from the power usage meter72and detection signals Po_s on the electric power sold output from the power selling meter73. The PLC transmitting element82performs communications with the fuel cell vehicle1aby using the power line85to carry data signals.

Hereinafter, with reference to the charts illustrated inFIG. 2toFIG. 5, descriptions will be carried out on processes performed respectively by the power supply controlling lenient62aand the power connection permitting element64.

STEP1to STEP4and STEP20to STEP21inFIG. 2are performed by the power connection permitting element64. At STEP1, when an open switch (not shown) of the movable cover10adisposed in the fuel cell vehicle1ais operated by a user (driver) of the fuel cell vehicle1a, the power connection permitting element64determines whether or not the shift lever is at the position of P (parking) according to the detection signals Sh_s output from the shift position sensor. When the shift lever is positioned at P, the fuel cell vehicle1ais in a state of being braked by a mechanical brake.

When the shift lever is determined to be positioned at P, the process moves to STEP2where the power connection permitting element64stops supplying electric power to the PDU40by switching off the motor switch35. Accordingly, the fuel cell vehicle1ais halted by the mechanical brake and the driving wheels thereof are unable to be driven by the motor41.

As mentioned, when the fuel cell vehicle1ais halted by the mechanical brake and the driving wheels thereof are unable to be driven by the motor41, the process moves to STEP3where the power connection permitting element64opens the movable cover10a. Accordingly, it is possible for the plug101of the power cable100to be inserted to the plug receptacle10.

On the other hand, when the shift lever is determined not to be at the position of P at STEP1, the process diverges to STEP20where the power connection permitting element64maintains the plug receptacle10as being covered by the movable cover10aas it was. Thereafter, the process moves to STEP21and the process is terminated. In this case, the plug101is prohibited from being inserted to the plug receptacle10by the user.

The process after STEP4is performed by the power supply controlling element62a. At STEP4, the power supply controlling element62aconfirms whether or not the PLC transmission is enabled between the controller60adisposed in the fuel cell vehicle1aand the controller80disposed in the house70. According to the confirmation result, the power supply controlling element62adetermines whether or not the plug receptacle10provided in the fuel cell vehicle1aand the power outlet71disposed in the house70are connected by the power cable100.

If the plug receptacle10provided in the fuel cell vehicle1aand the power outlet71disposed in the house7C is determined to have been connected, the process moves to STEP5where the power supply controlling element62adetermines whether or not the voltage of the commercial power source75in the house70is equal to or lower than a predefined low voltage level (for example, 85% of the output voltage of a normal commercial power source, or the upper limit of contracted power in a house is predicted to have been reached) according to data signals sent from the household power state detecting element81through the PLC transmitting element82.

If the voltage of the commercial power source75in the house70is determined to be equal to or lower than the predefined low voltage level, the process moves to STEP6inFIG. 3. On the other hand, if the voltage of the commercial power source75in the house70is determined to be greater than the predefined low voltage level, the process diverges to STEP30where the power supply controlling element62adetermines whether or not the temperature of the fuel cell20detected by the vehicular power state detecting element61ais equal to or higher than 0° C.

If the temperature of the fuel cell20is determined to be equal to or higher than 0° C. (in this case, the warm-up operation is not needed to be performed on the fuel cell20), the process diverges to STEP70in Fin.5where the power supply controlling element62adetermines whether or not it is necessary to charge the battery21and charges the battery21if it is needed. On the other hand, if the temperature of the fuel cell20is determined to be lower than 0° C. (in this case, the warm-up operation is necessary for the fuel cell20), the process moves to STEP31where the power supply controlling element62ainitiates the warm-up operation for the fuel cell20and the process moves to STEP6inFIG. 3. STEP6to STEP11inFIG. 3illustrate the warm-up operation for the fuel cell20.

Hereinafter, with reference toFIG. 3, descriptions will be carried out on process performed when the voltage of the commercial power source75in the house70is determined to be equal to or lower than the predefined low voltage level.

At STEP6, the power supply controlling element62adetermines whether or not the SOC of the battery21detected by the vehicular power state detecting element61ais equal to or greater than 35%. If the SOC of the battery21is determined to be equal to or greater than 35%, the process moves to STEP7where the power supply controlling element62acontrols the PDU42to generate electric power with a specification same as the output power from the commercial power source75by using the output power from the battery21and output it to the plug receptacle10. Accordingly, the output power from the battery21is supplied to the house70through the PDU42(the plug-out power supply) to assist the power supply by the commercial power source75in the house70.

While the electric power generated from the output power from the battery21with the same specification as the commercial power source75is being supplied, if the voltage of the commercial power source75in the house70is determined to be greater than the predefined low voltage level at STEP8, the plug-out power supply is sufficient. Therefore, the process returns to STEP6, the power supply controlling element62acontinues the plug-out power supply according to only the output power from the battery21.

On the other hand, if the voltage of the commercial power source75in the house70is determined to be lower than the predefined low voltage level at STEP8, the plug-out power supply is insufficient. Thus, the process moves to STEP9, the power supply controlling element62ainitiates the water pump, and at STEP10, the power supply controlling element62astarts supplying the reactant gases to the fuel cell20through the electric accessory device43.

At STEP11, the power supply controlling element62acontrols the PDU42to generate an electric power with the same specification as the output power from the commercial power source75by using the output power from the fuel cell20and output it to the plug receptacle10. Accordingly, the output power from the fuel cell20is supplied to the house70through the PDU42(the plug-out power supply) to assist the power supply by the commercial power source75in the house70. Thereafter, the process moves to STEP12and is terminated by the power supply controlling element62a.

Hereinafter, the warm-up operation of the fuel cell20will be explained with reference toFIG. 4.

At STEP32, the power supply controlling element62adetermines whether or not the generated power (warm-up electric power) of the fuel cell20detected by the vehicular power state detecting element61ais greater than the receivable power (maximum chargeable electric power) of the battery21detected by the vehicular power state detecting element61a. The warm-up operation is performed on the fuel cell20for 10 to 60 seconds with the generated power of the fuel cell20set at 10 to 30 kW, for example.

If the generated power from the fuel cell20is equal to or less than the receivable power of the battery21, the generated power from the fuel cell20can be completely consumed the battery21for charging. In this case, the process diverges to STEP40where the power supply controlling element62acharges the battery21using the generated power from the fuel cell20. Thereafter, the process moves to STEP36and is terminated by the power supply controlling element62a.

On the other hand, if the generated power from the fuel cell20is greater than the receivable power of the battery21, the generated power from the fuel cell20cannot be consumed the battery21for charging only. In this case, the process moves to STEP33where the cower supply controlling element62adetermines whether the generated power from the fuel cell20is greater than the sum of the consumed power by the electric accessory device43and the receivable power of the battery21.

If the generated power from the fuel cell20is equal to or less than the sum of the consumed power by the electric accessory device43and the receivable power of the battery21, the generated power from the fuel cell20can be completely consumed by the electric accessory device43and the battery21. In this case, the process diverges to STEP50where the power supply controlling element62adistributes the generated power from the fuel cell20to the electric accessory device43for consumption and the battery21for charging. Thereafter, the process moves to STEP36and is terminated by the power supply controlling element62a.

On the other hand, if the generated power from the fuel cell20is greater than the sum of the consumed power by the electric accessory device43and the receivable power of the battery21, the generated power from the fuel cell20cannot be consumed by the electric accessory device43and by the battery21through charging.

In this case, the process moves to STEP34where the power supply controlling element62adetermines whether or not the generated power from the fuel cell20is greater than the sum of the consumed power by electric home appliances in the house70(corresponding to the electric load of the present invention) and the consumed power by the electric accessory device43and the receivable power of the battery21.

If the generated power from the fuel cell20is equal to or less than the sum of the consumed power by the electric home appliances in the house70and the consumed power by the electric accessory device43and the receivable power of the battery21, he generated power from the fuel cell20can be completely consumed by the electric home appliances in the house70and the electric accessory device43and by the battery21through charging.

In this case, the process diverges to STEP60where the power supply controlling element62acontrols the PDU42to generate an electric power with the same specification as the output power from the commercial power source75by using a part of the output power from the fuel cell20and output it to the plug receptacle10. Accordingly, a part of the output power from the fuel cell20is supplied to the house70through the PDU42(the plug-out power supply) to be consumed effectively by the electric home appliances in the house70. Thereafter, the process moves to STEP36and is terminated by the power supply controlling element62a.

On the other hand, if the generated power from the fuel cell20is greater than the sum of the consumed power by the electric home appliances in the house70and the consumed power by the electric accessory device43and the receivable power of the battery21at STEP34, the generated power from the fuel cell20cannot be completely consumed by the electric home appliances in the house70and the electric accessory device43and by the battery21through charging.

In this case, the process moves to STEP35where the power supply controlling element62adistributes the generated power from the fuel cell20to the battery21for charging, the electric accessory device43and the electric home appliances in the house70for consumption, to a resistor (not shown) connected between the output terminals of the fuel cell20for consumption, and a return (power selling) from the house70to the commercial power line (of AC 100V, for example). Thereafter, the process moves to STEP36and is terminated by the power supply controlling element62a.

Hereinafter, with reference toFIG. 5, the charging process for the battery21will be explained.

At STEP70, the power supply controlling element62adetermines whether or not the SOC of the battery21detected by the vehicular power state detecting element61ais equal to or greater than 90%.

If the SOC of the battery21is determined to be equal to or greater than 90%, the battery21has sufficient charged power, and the process moves to STEP71where the power supply controlling element62aends the process without charging the battery21.

On the other hand, if the SOC of the battery21is determined to be less than 90% at STEP70, the process diverges to STEP80where the power supply controlling element62acontrols the PDU42to convert the electric power supplied from the house70via the power cable100into power to be provided to the battery21. Accordingly, the bower supply controlling element62acharges the battery21at STEP81. When the SOC of the battery becomes equal to or greater than 90% at the subsequent STEP82, the process moves to STEP71where the power supply controlling element62aends the process.

In the present embodiment, the fuel cell20and the lithium battery21are given as specific examples of the vehicular power sources of the present invention. However, a capacitor or a battery of the other kinds mounted in a vehicle may be used as the vehicular power source to supply electric power between the vehicle and a house according to the present invention.

In the present embodiment, when the warm-up operation is being performed on the fuel cell, the generated power according to the power generation of the fuel cell is supplied to the house and consumed by the electric home appliances in the house. However, even without the mentioned processes, the effect of the present invention can be obtained.

In the present embodiment, the fuel cell vehicle mounted with a fuel cell is given as an example of the vehicle of the present invention. However, it is also acceptable to use any vehicle provided with a power source, such as an electric vehicle or a hybrid electric vehicle, as the vehicle of the present invention.

Hereinafter, an embodiment where an electric vehicle or a hybrid electric vehicle is used as the vehicle of the present invention will be explained.

first, an embodiment where an electric vehicle1bis applied in the present invention will be explained with reference toFIG. 6.

FIG. 6illustrates an overall configuration of an electric power supply system between the electric vehicle (EV)1band a house. The same numerals are used to refer to the same or identical parts in the aforementioned embodiment related to the fuel cell vehicle1ainFIG. 1and descriptions thereof are omitted.

The electric vehicle1bis provided with a battery21(for example, a lithium battery equivalent to the electric accumulator of the present invention) serving as the vehicular power source of the present invention. According to the electric power supplied from the battery21, the PDU40provides the driving power to drive the motor41.

The controller60bis an electronic unit composed of a microcomputer (not shown) and the like. By causing the microcomputer to execute a control program configured to supply electric power between the electric vehicle1band the house70, the controller60bfunctions as a vehicular power state detecting element61b, a power supply controlling element62b, a PLC transmitting element63, and a power connection permitting element64.

Detection signals BT_s on the temperature, the terminal voltage, the output current and the like detected by the battery sensor52for the battery21are input into the controller60b. The operations or the DC/DC converter31, the PDU42, the motor switch35, the movable cover10aand the like are controlled according to control signals output from the controller60b, respectively.

The vehicular power state detecting element61bdetects the temperature, the terminal voltage, the output current, the SOC and the like for the battery21according to the detection signals BT_s output from the battery sensor52. The power supply controlling element62b, on the basis of the state of the battery21detected by the vehicular power state detecting element61band the state of the commercial power source in the house70detected by the household power state detecting element81, switches the plug-in power supply and the plug-out power supply.

When the plug receptacle10disposed in the electric vehicle1band the power outlet71disposed in the house70are connected by the power cable100, the power supply controlling element62bperforms the plug-in power supply if the SOC of the battery21is less than 90%. Accordingly, the battery21is charged by the electric power supplied from the house70.

When the battery21is charged, the temperature thereof will rise accordingly. Therefore, by charging the battery21, the power supply controlling element62bcan increase the SOC of the battery21and meanwhile can warm up the battery21.

When the SOC of the battery22reaches close to 100% where the battery21cannon be charged any further, the power supply controlling element62bperforms the plug-out power supply by discharging the battery21when the temperature of the battery21becomes equal to or lower than a predefined lower limit to supply the discharged power from the battery21to the house70. Meanwhile, the battery is heated according to the discharging (the warm-up operation of the battery21).

Hereinafter, an embodiment where a hybrid electric vehicle1cis applied in the present invention will be explained with reference toFIG. 7.

FIG. 7illustrates an overall configuration of an electric power supply system between the hybrid electric vehicle (HEV)1cand a house. The same numerals are used to refer to the same or identical parts in the aforementioned embodiment related to the fuel cell vehicle1ainFIG. 1and descriptions thereof are omitted.

The hybrid electric vehicle1cis provided with a battery21(for example, a lithium battery equivalent to the electric accumulator of the present invention) serving as the vehicular power source of the present invention. According to the electric power supplied from the battery21, the PDU40provides the driving power to drive the motor41.

A revolution shaft of the motor41is directly linked to a revolution shaft of en engine90, therefore, the driving force from the engine90and the motor41is transmitted to wheels92and92through a transmission91.

The motor41operates as a three-phase alternating current motor and a power generator. When the engine90is stopped, the driving force from the motor41is transmitted to the wheels92through the transmission91. When the engine90is running, the motor41is rotated by the engine90, which makes the motor41function as a power generator.

An engine controller95is an electric unit composed of a microcomputer (not shown) and the like. Detection signals on a revolution number of the engine90, a negative pressure of an intake, a water temperature and the like from the engine90and detection signals on stepped angles of an accelerator pedal96are input into the engine controller95. The engine controller95calculates an amount of fuels supplied to the engine90or an ignition timing according to the detection signals and outputs control signals on the fuel supply and the ignition timing to the engine90.

The engine controller95also controls operations of the motor41. The engine controller95outputs control signals for defining the output from the motor41to the PDU40. Further, instruction signals for defining an amount of power generated from the motor41is output from the controller60cto the engine controller95. According to the instruction signals, the engine controller95outputs control signals on the fuel supply and on the ignition timing to the engine90.

The motor41is provided with a rotor angle sensor93. The PDU40, on the basis of detected rotor angles from the rotor angle sensor93, outputs a driving voltage to drive the motor41and converts the generated electric bower from the motor41to direct-current power.

The controller60cis an electronic unit composed of a microcomputer (not shown) and the like. By causing the microcomputer to execute a control program configured to supply electric power between the hybrid electric vehicle1cand the house70, the controller60cfunctions as a vehicular power state detecting element61c, a power supply controlling element62c, a PLC transmitting element63, and a power connection permitting element64.

Detection signals BT_s on the temperature, the terminal voltage, the output current and the like detected by the battery sensor52for the battery21are input into the controller60c. The operations of the DC/DC converter31, the PDU42, the motor switch35, the movable cover10aand the like are controlled according to control signals output from the controller60c, respectively.

The vehicular power state detecting element61cdetects the temperature, the terminal voltage, the output current, the SOC and the like for the battery21according to the detection signals BT_s output from the battery sensor52. The power supply controlling element62c, on the basis of the state of the battery21detected by the vehicular power state detecting element61cand the state of the commercial power source in the house70detected by the household power state detecting element81, switches the plug-in power supply and the plug-out power supply.

When the plug receptacle10disposed in the hybrid electric vehicle1cand the power outlet71disposed in the house70are connected by the power cable100, the power supply controlling element62cperforms the plug-in power supply if the SOC of the battery21is less than 90%. Accordingly, the battery21is charged by the electric power supplied from the house70.

The temperature of the battery21rises due to the charging. Therefore, by charging the battery21, the power supply controlling element62ccan increase the SOC of the battery21and meanwhile can warm up the battery21.

When the SOC of the battery21reaches close to 100% and the battery21cannot be charged any further, the power supply controlling element62cperforms the plug-out power supply by discharging the battery21when the temperature of the battery21becomes equal to or lower than a predefined lower limit supply the discharged power from the battery21to the house70.

Meanwhile, the battery21is heated according to the discharging (first warm-up operation of the battery21).

Moreover, when the SOC of the battery21is too low to heat the battery21by discharging and the house70cannot afford sufficient electric power to charge the battery21according to the plug-in power, the power supply controlling element62cinitiates engine90to operate the motor41as a power generator. Therefore, the power supply controlling element62ccan charge the battery21according to the electric power generated from the motor41, and meanwhile, supplies a part the generated electric power by the motor41to the house70according to the plug-out power supply (second warm-up operation of the battery21).

According thereto, the battery21can be heated through charging, and meanwhile, the power supply by the commercial power source75to the house70can be assisted according to the plug-out power supply.

In the present embodiment, the system is explained as including a power connection permitting element which permits the connection of a vehicle and a house through a power cable when the shift lever of the vehicle is set at the position of P (parking) and the electric power supply to the motor is switched off. The present invention is not limited thereto. The effect of the present invention can be achieved without providing the power connection permitting element.