JP5971601B2 - Electric vehicle power supply system - Google Patents

Description

  The present invention relates to an electric vehicle power feeding system.

  In recent years, electric vehicles such as plug-in hybrid vehicles (PHVs) and battery vehicles (BEV: Barttery Electric Viecle) have been developed. It is being considered to charge an electric vehicle by supplying a commercial AC power source.

  In addition, when a power failure occurs while a commercial AC power supply is being supplied to an electric vehicle and the battery is being charged, the battery of the electric vehicle is discharged and power is supplied to the electric devices in the house. It has been studied (see, for example, Patent Document 1).

JP 2006-158084 A

  In the system disclosed in Patent Document 1 described above, when charging the electric vehicle, commercial AC power is supplied to the electric vehicle, and the battery is charged by converting the alternating current into direct current inside the electric vehicle. There was a problem that conversion loss occurred when converting to. Moreover, since the DC power stored in the battery is converted into AC power and supplied to the house side when the electric vehicle is discharged, there is a problem that conversion loss occurs when DC is converted into AC.

  The present invention has been made in view of the above problems, and the object of the present invention is to convert AC-DC or DC-DC when charging an electric vehicle battery or discharging the battery to supply power to the house. An object of the present invention is to provide an electric vehicle power supply system that eliminates the need for alternating current conversion and efficiently uses power.

In order to achieve the above object, an electric vehicle power feeding system of the present invention is arranged in a building, and a DC distribution board that distributes DC power supplied from a DC power source to a branch circuit arranged in the building; Bidirectionally configured to perform a charging operation for supplying DC power from the DC distribution board to a battery of an electric vehicle and a power supply operation for supplying DC power from the battery of the electric vehicle to the DC distribution board a power feeding unit, on the basis of the DC power supply by the power supply amount and the amount of electric power used in the branch circuit, to generate a switching signal for switching the operation of the bidirectional power feeding device to either the charging operation and the feeding operation A control unit configured to switch the electric vehicle to either the battery charging operation or the power feeding operation based on the switching signal; A vehicle-side power supply unit that supplies DC power from the DC distribution board to the electric vehicle when the electric vehicle is charged, and a component that supplies DC power from the electric vehicle to the DC distribution panel when the electric vehicle is discharged The DC distribution board includes, as the DC power source , an AC / DC converter that converts AC power supplied from a commercial AC power source into DC, and a DC voltage generated by the power generator. A first DC / DC converter that converts a voltage value; and a second DC / DC converter that converts a voltage value of a DC voltage supplied from a storage battery installed in the building. The power supply amount of each of the AC / DC converter, the first DC / DC converter, and the second DC / DC converter is controlled .

  According to the present invention, when the battery is charged by supplying power to the charging / discharging unit of the electric vehicle, DC power is supplied from the DC distribution board to the electric vehicle via the bidirectional power supply device. There is no need to convert AC to DC on the side, and no conversion loss occurs during AC-DC conversion. Moreover, even when the battery is discharged by the charging / discharging unit of the electric vehicle and power is supplied from the electric vehicle side, the bidirectional power supply device supplies the DC power stored in the battery of the electric vehicle to the DC distribution board as it is. Therefore, there is no need to convert the DC power supplied from the electric vehicle into AC, and conversion loss during DC-AC conversion does not occur, so that the power can be used efficiently.

It is a system configuration figure of this embodiment. It is a system block diagram which shows the other system configuration same as the above.

  Embodiments of the present invention will be described below with reference to the drawings.

  The electric vehicle power supply system according to the present embodiment supplies direct current power to an electric vehicle such as a plug-in hybrid vehicle (PHV) or a battery vehicle (BEV) to charge the electric vehicle. The battery of an automobile is discharged and the electric power charged in the battery is supplied to the dwelling unit side. In addition, although this embodiment demonstrates the form which applied the electric vehicle electric power feeding system to the detached dwelling unit, it cannot be overemphasized that an electric vehicle electric power feeding system may be applied to buildings, such as an apartment house and a business establishment.

  FIG. 1 is a schematic block diagram of an electric vehicle power supply system, which is arranged in a dwelling unit H, and distributes DC power supplied from a DC power source to a branch circuit arranged in the dwelling unit H. The charging operation for supplying the DC power supplied from the DC distribution board 1 to the charging / discharging circuit 63 of the electric vehicle 60 or the DC power supplied from the charging / discharging circuit 63 of the electric vehicle 60 is supplied to the DC distribution board 1. A bidirectional power feeding device 2 that performs any one of the power feeding operations, a control device 3, and a setting display device 4 are provided.

  Here, the electric vehicle 60 includes a connector 61 that is detachably connected to the connector 26 provided at the tip of the charging cable CA from the bidirectional power feeding device 2, a battery 62 such as a lithium ion battery, and the battery 62. The charging / discharging circuit 63 for charging or discharging, the communication circuit 64 for communicating with the bidirectional power feeding device 2, and the charging / discharging circuit 63 based on the switching signal from the bidirectional power feeding device 2 received by the communication circuit 64. And a charge / discharge control circuit 65 that switches the operation to either a charging operation or a power feeding operation.

On the other hand, the DC distribution board 1 is compatible with a DC voltage of 300V class, and cooperates with the control unit 11 for supplying DC power from a plurality of DC power sources to the load circuit in cooperation with the output terminal of the cooperation control unit 11. And a plurality of DC breakers 12 respectively connected between a plurality of branch circuits. The DC distribution board 1 includes a DC / DC converter 13 (first DC / DC converter) that converts a DC voltage generated by the photovoltaic power generation facility 50 into a DC voltage having a predetermined voltage value, and a fuel cell (FC). The DC / DC converter 14 (first DC / DC converter) that converts the DC voltage generated by the fuel cell 51 into a DC voltage having a predetermined voltage value, and another DC power source and another DC power source. A DC / DC converter 15 (second DC / DC converter) that converts a DC voltage supplied from the storage battery 52 that is discharged when the power supply stops feeding into a DC voltage of a predetermined voltage value, and a commercial AC power supply AC An AC / DC converter 16 that receives supply of alternating current power and converts it into direct current is housed. The outputs of the DC / DC converters 13 to 15 and the AC / DC converter 16 are It is connected to the cooperation control section 11 via a flow power line L1. Here, in this embodiment, the photovoltaic power generation facility 50, the fuel cell 51, the storage battery 52, and the DC / DC converters 13 to 15 that convert the output thereof to a predetermined voltage value, or the AC input of the commercial AC power source AC to DC An AC / DC converter 16 for conversion is provided as a DC power source.

  In addition, the bidirectional power supply device 2 converts a DC power supplied from the DC breaker 12 into a voltage value corresponding to the electric vehicle 60 and supplies the voltage to the electric vehicle 60 side (vehicle-side power supply unit); Signals are exchanged between the control device 3 and the DC / DC converter 22 (distribution panel side power supply unit) that converts the voltage value of the DC voltage supplied from the electric vehicle 60 and outputs it to the DC power line L1. Based on the signal received from the control device 3 or the electric vehicle 60, the communication unit 25 that performs communication between the interface unit 24 (I / F) and the communication circuit 64 of the electric vehicle 60 via the communication line L4. And a control unit 23 that controls the operation of the converters 21 and 22. In the present embodiment, signals are exchanged between the communication unit 25 of the bidirectional power feeding device 2 and the communication circuit 64 of the electric vehicle 60 via a dedicated communication line L4 incorporated in the charging cable CA. However, the signal may be superimposed by power line carrier communication via the power line L3, or the signal may be exchanged by short-range wireless communication.

  The control device 3 has a function of controlling the power supply amount of the DC power supplied from the DC distribution board 1, and by individually adjusting the power supply amounts of the DC / DC converters 13 to 15 and the AC / DC converter 16. The power supply ratio of a plurality of DC power supplies is set. The control device 3 also has a function of transmitting power supply capability information from a plurality of DC power supplies to the bidirectional power supply device 2. The bidirectional power supply device 2 also has information on power supply capability transmitted from the control device 3. In addition, the DC power supplied to the electric vehicle 60 is controlled by controlling the DC / DC converter 21 so as not to exceed the power supply capability of the DC power supply.

  The setting display device 4 includes a touch panel type liquid crystal monitor, and the power supply status of the DC power source is displayed on the screen, and various settings are made to the control device 3 by touching operation buttons displayed on the screen. Data can be set.

  Here, the charging / discharging operation of the electric vehicle 60 by the power feeding system will be described.

  The control device 3 compares the amount of power supplied by the DC power supply with the amount of power used on the branch circuit side. If the power supply amount of the DC power supply exceeds the amount of power used, the bidirectional power supply device 2 A switching signal for switching the operation to the charging operation is transmitted to the bidirectional power feeding device 2, the electric power feeding device 2 feeds power to the electric vehicle 60 side, and the battery 62 of the electric vehicle 60 is preferentially charged. Then, when the charging of the battery 62 is completed, the control device 3 causes the storage battery 52 to be charged next, and when the charging of the storage battery 52 is also completed, the control device 3 converts it into an AC power source by a DC / AC converter (not shown). You may supply to an apparatus. On the other hand, when the power supply amount of the DC power source is lower than the power consumption amount, the storage battery 52 is first discharged, and then a switching signal for switching the operation of the bidirectional power supply device 2 to the power supply operation is sent to the bidirectional power supply device 2. The DC power transmitted and discharged from the battery 62 of the electric vehicle 60 by the bidirectional power supply device 2 is fed to the DC distribution board 1 side.

  Here, when charging the electric vehicle 60, when the connector 26 of the charging cable CA derived from the bidirectional power supply device 2 is connected to the connector 61 of the electric vehicle 60, the control unit 23 of the bidirectional power supply device 2 A charging information transmission request for requesting transmission of charging information related to the charging voltage and charging current is transmitted from the communication unit 25 to the electric vehicle 60 side. When the communication circuit 64 of the electric vehicle 60 receives the charging information transmission request transmitted from the bidirectional power supply device 2, the charging / discharging control circuit 65 sends both charging information related to its own charging voltage and charging current from the communication circuit 64. Transmission to the direction feeding device 2 is performed. When the charging information is received by the communication unit 25 of the bidirectional power supply device 2, the control unit 23 of the bidirectional power supply device 2 receives the charging information received by the communication unit 25 and the control device 3 via the interface unit 24. Based on the obtained power supply capability of the DC power supply, it is determined whether or not power supply from the DC distribution board 1 is possible, and a DC / DC value is determined based on the current value that can be supplied and the voltage value requested from the electric vehicle 60 side. The output of the DC converter 21 is controlled to supply power to the electric vehicle 60 side.

  In the present embodiment, as a DC power source for supplying DC power to the DC distribution board 1, the photovoltaic power generation facility 50, the fuel cell 51, the storage battery 52, and the commercial AC power source AC are converted to DC by the AC / DC converter 16. Although the DC power source obtained by the conversion is used, the control device 3 automatically executes a process of selecting a DC power source to be fed to the electric vehicle 60 from a plurality of DC power sources.

  For example, when charging the battery 62 on the electric vehicle 60 side, the amount of power supplied from the AC / DC converter 16 that converts the AC input of the commercial AC power supply AC into DC is set to zero using the setting display device 4. In the case where sunlight is present (that is, power is generated by the photovoltaic power generation facility 50) and the remaining charge is present in the storage battery 52, the electric vehicle 60 responds to the charging information transmission request and sets the charging voltage to DC300V, When charging information with a charging current of 20 A is returned to the bidirectional power supply device 2, the charging information is further transmitted from the bidirectional power supply device 2 to the control device 3. The control device 3 knows the power supply capability of each DC power source, and the generated power of the solar power generation facility 50 is 2000 VA, the generated power of the fuel cell 51 is 0 VA, and the remaining charge of the storage battery 52 is 1000 VA. If there is no power consumption by other electrical devices in H, the power that can be supplied to the electric vehicle 60 is set to 3000 VA. The control device 3 controls the DC / DC converters 13 and 15 to supply the electric vehicle 60 with a power supply voltage of DC 300 V and a power supply current of 10 A using the photovoltaic power generation facility 50 and the storage battery 52 as power sources. When there is no sunlight in the above power supply situation, the control device 3 determines that the electric power that can be supplied to the electric vehicle 60 is 1000 VA of the storage battery 52, controls the DC / DC converter 15, and uses the storage battery 52 as a power source. 60 is fed with a feeding voltage of 300V and a feeding current of 3.3A. In addition, when the power supply amount from the AC / DC converter 16 that converts the AC input of the commercial AC power supply AC to DC is set to 1000 VA, when there is no sunlight and the battery 52 has a remaining charge of 1000 VA, The control device 3 determines that the electric power that can be supplied to the electric vehicle 60 is 2000 VA, controls the DC / DC converter 15 and the AC / DC converter 16, and converts the AC input from the commercial AC power source AC to DC. The converter 16 and the storage battery 52 are used as power sources to supply power to the electric vehicle 60 with a power supply voltage of DC 300 V and a power supply current of 6.6 A. The control device 3 automatically selects an optimum DC power source according to preset selection conditions. However, the type of DC power source to be preferentially fed using the setting display device 4 is registered in advance. It is also possible to keep it.

  As described above, DC power is supplied from the DC distribution board 1 to the electric vehicle 60 side, and the battery 62 is charged by the charging / discharging circuit 63 of the electric vehicle 60. However, when power supply from the DC power supply is stopped. Is transmitted from the control device 3 to the electric vehicle 60 via the bidirectional power supply device 2, and the charge / discharge circuit 63 of the electric vehicle 60 discharges the battery 62, and the direct current is transferred from the battery 62 to the DC distribution board 1 side. Power is supplied.

  For example, while the electric vehicle 60 is charged at night or the like, the power conversion from the commercial AC power supply AC is set to the minimum using the setting display device 4, and the scheduled travel distance of the next day is set to 50 km. In this case, since the power generated by the solar power generation facility 50 is lost at night, the fuel cell 51 and the storage battery 52 are used as power sources to charge the electric vehicle 60 and to supply power to the load in the dwelling unit H. Here, when the power supply capability of the fuel cell 51 and the storage battery 52 is less than the load power used, the control device 3 discharges the battery 62 from the charge operation of charging the battery 62 of the electric vehicle 60 (power supply operation). A switching signal for switching to is output to the bidirectional power feeding device 2, and this switching signal is transmitted from the bidirectional power feeding device 2 to the electric vehicle 60. At this time, the charging / discharging control circuit 65 of the electric vehicle 60 causes the charging / discharging circuit 63 to perform a discharging operation (power feeding operation) based on the switching signal received by the communication circuit 64 and uses the DC power stored in the battery 62 as a power line. It discharges to the bidirectional | two-way electric power feeder 2 via L3. In the bidirectional power supply device 2, the control unit 23 stops the operation of the DC / DC converter 21 according to the switching signal input from the control device 3 and is supplied from the electric vehicle 60 by the DC / DC converter 22. The DC voltage (for example, DC300V) is converted into a transmission voltage value in the house (for example, DC350V) and output to the DC power wiring L1, and the DC power is supplied to the load in the dwelling unit H using the battery 62 of the electric vehicle 60 as a power source. Can be supplied.

  By the way, when the scheduled travel distance for the next day is set using the setting display device 4, the scheduled travel distance setting information is transmitted from the control device 3 to the electric vehicle 60 via the bidirectional power feeding device 2. The charge / discharge control circuit 65 of the electric vehicle 60 sets the required battery capacity required to travel the planned travel distance based on the setting information received from the bidirectional power supply device 2. Then, in the charge / discharge control circuit 65, when discharging of the battery 62 is started according to the switching signal input from the bidirectional power supply device 2, the remaining capacity of the battery 62 is compared with the required battery capacity, and the remaining capacity is determined. When the battery capacity is less than the required battery capacity, the charging / discharging circuit 63 is controlled to automatically stop discharging of the battery 62, so that the battery capacity necessary to travel the next scheduled travel distance can be ensured.

  In addition, when the discharge of the battery 62 is stopped, the charge / discharge control circuit 65 transmits a discharge stop signal for notifying the stop of the discharge from the communication circuit 64 to the bidirectional power supply device 2. Is received, the operation of the DC / DC converter 22 is stopped and a discharge stop signal is transmitted from the interface unit 24 to the control device 3. When the control device 3 receives this discharge stop signal, the control device 3 operates the AC / DC converter 16 to compensate for the shortage of power due to the stop of the discharge from the electric vehicle 60, and the AC / DC converter. The commercial AC power supply AC is converted into DC power by 16 and DC power is supplied to the load together with the storage battery 52.

  Note that when an overcurrent or a leakage occurs when the battery 62 of the electric vehicle 60 is discharged and the discharged power is supplied to the DC distribution system in the dwelling unit H, the DC provided in the DC distribution board 1 It is protected by a breaker 12 or a leakage breaker (not shown).

  As described above, in this electric vehicle power supply system, when the battery 62 of the electric vehicle 60 is charged, DC power is supplied from the DC distribution board 1 to the electric vehicle 60 via the bidirectional power supply device 2. Therefore, there is no need to convert alternating current into direct current on the electric vehicle 60 side, and no conversion loss occurs during alternating current-direct current conversion. In addition, when the battery 62 of the electric vehicle 60 is discharged and power is supplied from the side of the electric vehicle 60, the bidirectional power supply device 2 uses the direct current power stored in the battery 62 of the electric vehicle 60 to the DC distribution board 1. Since it is supplied as it is, there is no need to convert the DC power supplied from the electric vehicle 60 into AC, and no conversion loss occurs at the time of DC-AC conversion, so that the power can be used efficiently. it can.

  In the electric vehicle power supply system described above, the DC power discharged from the battery 62 of the electric vehicle 60 may be charged in the storage battery 52, and the DC power stored in the battery 62 of the electric vehicle 60 is used as a load in the dwelling unit H. Can be used effectively.

  In the electric vehicle power supply system described above, the bidirectional power supply device 2 includes two DC / DC converters 21 and 22, and during charging, the DC-DC converter 21 performs voltage conversion of DC power supplied from the house side. At the time of discharge and supplied to the electric vehicle 60 side, the DC / DC converter 22 converts the DC voltage supplied from the electric vehicle 60 and supplies it to the house side. As shown in FIG. A DC / DC converter 27 that performs both charging from the vehicle and discharging from the vehicle side may be provided. The operation of the DC / DC converter 27 is controlled by a control signal from the control unit 23, converts the voltage of DC power supplied via the DC breaker 12 during charging, supplies the voltage to the electric vehicle 60, and discharges the electric vehicle. The voltage value of the DC voltage supplied from 60 is converted and supplied to the house side (cooperative control unit 11).

  The electric vehicle power supply system includes a storage battery that is charged with DC power supplied from another DC power source as a DC power source and that discharges when the other DC power source stops power supply. The storage battery may be charged by DC power supplied from the power board side power supply unit. Thereby, the direct-current power discharged from the battery of the electric vehicle can be charged to the storage battery.

DESCRIPTION OF SYMBOLS 1 DC distribution board 2 Bidirectional electric power feeder 3 Control apparatus 4 Setting display apparatus (setting apparatus)
21 DC / DC converter (car-side power supply unit)
22 DC / DC converter (distribution panel side feeding section)
23 control unit 60 electric vehicle 62 battery 63 charge / discharge circuit (charge / discharge unit)
65 Charge / Discharge Control Circuit (Charge / Discharge Control Unit)

Claims (2)

A DC distribution board arranged in a building and distributing DC power supplied from a DC power source to a branch circuit arranged in the building;
Bidirectionally configured to perform a charging operation for supplying DC power from the DC distribution board to a battery of an electric vehicle and a power supply operation for supplying DC power from the battery of the electric vehicle to the DC distribution board A power supply device;
Wherein based on the amount of electric power used in the branch circuit and the power supply amount of the DC power source, configured to generate a switching signal for switching the operation of the bidirectional power feeding device to either the charging operation and the feeding operation A control device,
The bidirectional power feeding device includes a control unit that switches the electric vehicle to either a charging operation or a feeding operation of the battery based on the switching signal, and a direct current from the direct current distribution board when the electric vehicle is charged. A vehicle-side power supply unit that supplies power to the electric vehicle; and a distribution board-side power supply unit that supplies DC power from the electric vehicle to the DC distribution panel when the electric vehicle is discharged.
The DC distribution board includes, as the DC power source , an AC / DC converter that converts AC power supplied from a commercial AC power source into DC, and a first DC that converts a voltage value of a DC voltage generated by a power generator. A DC / DC converter and a second DC / DC converter that converts a voltage value of a DC voltage supplied from a storage battery installed in the building,
The control device is configured to control power supply amounts of the AC / DC converter, the first DC / DC converter, and the second DC / DC converter, respectively. Electric vehicle power supply system.   The electric vehicle power supply system according to claim 1, further comprising a setting device that sets a power supply amount of the AC / DC converter according to an operation.

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