Charging and discharging relay device

Abstract

A charge / discharge relay device is provided that can properly charge and discharge a vehicle-side storage battery of an electric vehicle when the vehicle-side storage battery of the electric vehicle and a power supply device installed in a facility are interconnected by the facility's power line. [Solution] When the relay circuit unit 21 is electrically connected to the inverter 42 of the electric vehicle 40, the relay side control unit 33 of the charge / discharge relay device 20 acquires information capable of identifying the type of the electric vehicle 40 from the vehicle side control unit 47, and performs a charge / discharge feasibility determination process to determine whether or not to permit power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40, and whether or not to permit power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21, based on the information capable of identifying the type of power supply device 51 connected to the facility side power line 2, the charging feasibility information, and the discharging feasibility information.

Description

[Technical Field]

[0001] The present invention relates to a charge / discharge relay device. [Background technology]

[0002] Patent Document 1 (Japanese Patent No. 5355641) describes a configuration in which a storage battery (vehicle storage battery 24) of an electric vehicle (automobile 22) is connected to a power line installed in a facility (building 12) using a cable (26). In this case, the electrical connection between the facility's power line and the storage battery is relayed by a control device (14) installed in the facility. Specifically, the control device (14) has a function of converting AC power to DC power and DC power to AC power, and performs control such as converting power supplied from a power grid (system power supply 20) into DC power and supplying it to the storage battery to charge it, and converting power stored in the storage battery into AC power and supplying it to electrical equipment (16) in the facility. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5355641 Summary of the Invention [Problem to be solved by the invention]

[0004] In some cases, an existing power supply device such as a fuel cell device is installed on the power line of a facility (building 12) to which an electric vehicle (automobile 22) such as that described in Patent Document 1 is connected. The power supply device may operate in a way that causes a reverse flow of power to the power grid, or in a way that does not cause a reverse flow.

[0005] In this case, the electric vehicle cannot know whether a power supply device is connected to the facility's power line. Therefore, if an electric vehicle connected to a facility's power line is configured to detect the presence or absence of a reverse flow of power from the power line to the power grid, an abnormal state may occur in which, from the electric vehicle's perspective, power is output from the power supply device to the power line, causing a reverse flow of power from the power line to the power grid, even though the electric vehicle is not supplying power to the power line. In other words, if a storage battery of an electric vehicle and a power supply device that causes a reverse flow of power to the power grid are interconnected by the facility's power line, it may not be appropriate to cause a reverse flow of power from the storage battery of the electric vehicle to the power grid.

[0006] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a charge / discharge relay device that can properly charge and discharge the vehicle-side battery of an electric vehicle when the vehicle-side battery of the electric vehicle and a power supply device installed in a facility are interconnected by the facility's power line. [Means for solving the problem]

[0007] A characteristic configuration of a charge / discharge relay device according to the present invention for achieving the above object is a charge / discharge relay device that is installed in a facility, electrically connects a facility-side power line that is linked to an electric power grid to an inverter of an electric vehicle using a relay circuit unit, and relays charging to and discharging from a vehicle-side storage battery of the electric vehicle that is connected to the inverter, a relay-side storage unit that stores, when the inverter of the electric vehicle is connected to the facility-side power line via the relay circuit unit and a power supply device provided in the facility is connected to the facility-side power line, charging enable / disable information indicating whether or not power supply from the relay circuit unit to the inverter of the electric vehicle is permitted, and discharging enable / disable information indicating whether or not power supply from the inverter of the electric vehicle to the relay circuit unit is permitted, for each combination of one or more types of the electric vehicle and one or more types of the power supply device connected to the facility-side power line; a relay-side control unit capable of communicating information with a vehicle-side control unit that controls the operation of the inverter of the electric vehicle; When the relay circuit unit is electrically connected to the inverter of the electric vehicle, the relay-side control unit acquires information capable of identifying the type of the electric vehicle from the vehicle-side control unit, and performs a charge / discharge enable / disable determination process that determines whether or not to permit power supply from the relay circuit unit to the inverter of the electric vehicle, and whether or not to permit power supply from the inverter of the electric vehicle to the relay circuit unit, based on the information capable of identifying the type of the power supply device connected to the facility-side power line, the charge enable / disable information, and the discharge enable / disable information.

[0008] According to the above characteristic configuration, the compatibility of each combination of one or more types of electric vehicles and one or more types of power supply devices can be examined in advance, such as whether or not a malfunction will occur when they are interconnected. The relay-side storage unit can then store charging availability information indicating whether or not to permit power supply from the relay circuit unit to the inverter of the electric vehicle when the two are connected to the facility-side power line, and discharging availability information indicating whether or not to permit power supply from the inverter of the electric vehicle to the relay circuit unit. When the electric vehicle actually arrives at the facility and the relay circuit unit is electrically connected to the inverter of the electric vehicle, the relay-side control unit acquires information identifying the type of the electric vehicle from the vehicle-side control unit, and performs a charging / discharging availability determination process to determine whether or not to permit power supply from the relay circuit unit to the inverter of the electric vehicle and whether or not to permit power supply from the inverter of the electric vehicle to the relay circuit unit based on the information identifying the type of power supply device connected to the facility-side power line, the charging availability information, and the discharging availability information. In other words, malfunctions can be avoided when the electric vehicle and the power supply device are interconnected, regardless of the type of electric vehicle that arrives at the facility. Therefore, when the vehicle-side storage battery of an electric vehicle and a power supply device installed in a facility are interconnected via the facility's power line, a charge / discharge relay device can be provided that can properly charge and discharge the vehicle-side storage battery of an electric vehicle.

[0009] Another characteristic configuration of the charge / discharge relay device of the present invention is that the charging / discharging capability information and the discharging / discharging capability information include information that is determined depending on whether the power supply device operates so as not to cause reverse power flow to the power grid.

[0010] When a power supply device causes a reverse flow of power to the power grid, an electric vehicle, which is unaware of the existence of the power supply device, may become aware of an abnormal state in which power is being output from the power supply device to the power line, causing power to flow reversely to the power grid, even though the electric vehicle itself is not discharging power. Therefore, in this characteristic configuration, the charge permission information and the discharge permission information include information determined depending on whether the power supply device operates to prevent reverse power flow to the power grid. That is, for example, the discharge permission information may store information indicating that discharge from the electric vehicle is not permitted when the power supply device operates to prevent reverse power flow to the power grid, and the discharge permission information may store information indicating that discharge from the electric vehicle is permitted when the power supply device operates to prevent reverse power flow to the power grid, thereby preventing the above problem from occurring.

[0011] Another characteristic configuration of the charge / discharge relay device according to the present invention is that the charging / discharging capability information and the discharging capability information include information that is determined depending on whether the power supply device and the inverter of the electric vehicle are electrically connected to each other when the facility-side power line is in an autonomous state and not connected to the power grid.

[0012] There are power supply devices that output power only to a dedicated stand-alone output line when the facility-side power line is in an independent state and not connected to the power grid. In such cases, when the facility-side power line is in an independent state and not connected to the power grid, the power supply device and the inverter of the electric vehicle are not electrically connected to each other, so there is no need to consider whether a malfunction will occur if the electric vehicle and the power supply device are interconnected. Therefore, in this characteristic configuration, the charge enable / discharge enable / disable information includes information that is determined depending on whether the power supply device and the inverter of the electric vehicle are electrically connected to each other in an independent state when the facility-side power line is not connected to the power grid. In other words, when the power supply device and the inverter of the electric vehicle are not electrically connected to each other in an independent state, it is possible to determine whether to permit power supply from the relay circuit unit to the inverter of the electric vehicle, and whether to permit power supply from the inverter of the electric vehicle to the relay circuit unit, without considering whether a malfunction would occur if the power supply device and the inverter of the electric vehicle were connected to each other.

[0013] Another characteristic configuration of the charge / discharge relay device according to the present invention is a first electric circuit unit that is used for electrically connecting to the facility side power line and that is composed of an N phase that is a neutral line, a U phase that is a voltage line, and a V phase that is a voltage line; a second electric circuit unit configured with a U-phase voltage line and a V-phase voltage line, the second electric circuit unit being used for electrically connecting to the inverter of the electric vehicle; and a grid connection protection unit that performs a protective operation required when the inverter of the electric vehicle is connected to the power grid via the facility-side power line, based on the voltage between the U phase and the N phase and the voltage between the V phase and the N phase in the first electric circuit unit.

[0014] According to the above characteristic configuration, the interconnection protection unit of the charge / discharge relay device performs a protective operation required when the inverter of the electric vehicle is interconnected to the power grid via the facility-side power line, based on the voltage between the U phase and the N phase and the voltage between the V phase and the N phase in the first electric circuit unit, which is composed of the N phase as a neutral line, the U phase as a voltage line, and the V phase as a voltage line, used for electrically connecting to the facility-side power line. In other words, the provision of the interconnection protection unit in the charge / discharge relay device enables two-phase monitoring.

[0015] Another characteristic feature of the charge / discharge relay device of the present invention is that it includes a relay-side storage battery that can be charged with power supplied from the facility-side power line and power supplied from the electric vehicle, and that can supply the charged power to the interconnection protection unit.

[0016] According to the above characteristic configuration, since the charge / discharge relay device is equipped with a relay-side storage battery, even in an abnormal state where power is not being supplied normally from the power system (i.e., even if power is not being supplied normally from the facility-side power line to the charge / discharge relay device), the interconnection protection unit can use the power supplied from the relay-side storage battery to perform protective operations such as electrically disconnecting the inverter of the electric vehicle from the power system when low voltage is detected in the power system.

[0017] Another characteristic feature of the charge / discharge relay device according to the present invention is that the measurement result of a power meter that measures the power at the receiving point of the facility is transmitted to the electric vehicle.

[0018] According to the above characteristic configuration, in the electric vehicle, the operation of the inverter can be controlled so that the discharged power of the vehicle-side storage battery is not reversely flowed to the power grid.

[0019] Another characteristic feature of the charge / discharge relay device of the present invention is that it includes a connection section that connects the N phase, which is a neutral line, the U phase, which is a voltage line, and the V phase, which are voltage lines that constitute the first electrical circuit section, with the U phase, which is a voltage line, and the V phase, which are voltage lines that constitute the second electrical circuit section.

[0020] According to the above characteristic configuration, the connection portion can connect a first electrical circuit portion consisting of an N phase which is a neutral line, a U phase which is a voltage line, and a V phase which is a voltage line, to a second electrical circuit portion consisting of a U phase which is a voltage line and a V phase which is a voltage line.

[0021] Another characteristic feature of the charge / discharge relay device of the present invention is that the relay-side control unit allows power supply from the facility-side power line to the inverter of the electric vehicle even if a corresponding combination of the electric vehicle and the power supply device does not exist or if information communication with the vehicle-side control unit is not possible.

[0022] According to the above characteristic configuration, if a corresponding combination of an electric vehicle and a power supply device does not exist, or if information communication with the vehicle-side control unit of the electric vehicle is not possible, the charge / discharge relay device cannot verify whether or not it is permissible to supply power from the inverter of the electric vehicle to the facility-side power line while the inverter of the electric vehicle is connected to the power grid, but it is possible to supply power from the facility-side power line to the inverter of the electric vehicle (i.e., charge the vehicle-side storage battery).

[0023] Another characteristic configuration of the charge / discharge relay device according to the present invention is that the relay-side storage unit stores authentication information about hardware included in the authenticated electric vehicle, The relay side control unit When the relay circuit unit is electrically connected to the inverter of the electric vehicle, information about the hardware is acquired from the electric vehicle, and a vehicle determination process is performed to determine whether the hardware of the electric vehicle is identical to the authenticated hardware based on the authentication information stored in the relay-side storage unit; When it is determined in the vehicle determination process that the hardware of the electric vehicle is identical to that authenticated, permitting the supply of power from the inverter of the electric vehicle to the relay circuit unit on the condition that the supply of power from the inverter of the electric vehicle to the relay circuit unit is permitted in the charge / discharge permission determination process; If the vehicle determination process determines that the hardware of the electric vehicle is not the same as that authenticated, the supply of power from the inverter of the electric vehicle to the relay circuit unit is prohibited regardless of whether the charge / discharge feasibility determination process has permitted the supply of power from the inverter of the electric vehicle to the relay circuit unit.

[0024] According to the above characteristic configuration, when the relay circuit unit is electrically connected to the inverter of the electric vehicle, the relay-side control unit acquires information about the hardware from the electric vehicle. The relay-side control unit then performs a vehicle determination process to determine whether the hardware of the electric vehicle is identical to the authenticated hardware based on the authentication information stored in the relay-side storage unit. That is, the vehicle determination process determines whether the hardware (inverter) of the electric vehicle has the configuration as previously applied. If the relay-side control unit determines in the vehicle determination process that the hardware of the electric vehicle is identical to the authenticated hardware, the relay-side control unit permits the supply of power from the inverter of the electric vehicle to the relay circuit unit, provided that the charge / discharge permission determination process has permitted the supply of power from the inverter of the electric vehicle to the relay circuit unit. If the relay-side control unit determines in the vehicle determination process that the hardware of the electric vehicle is not identical to the authenticated hardware, the relay-side control unit prohibits the supply of power from the inverter of the electric vehicle to the relay circuit unit, regardless of whether the charge / discharge permission determination process has permitted the supply of power from the inverter of the electric vehicle to the relay circuit unit.

[0025] Another characteristic configuration of the charge / discharge relay device of the present invention is that when the relay side control unit determines in the vehicle determination process that the hardware of the electric vehicle is not the same as that authenticated, it allows the relay circuit unit to supply power to the inverter of the electric vehicle, provided that the charge / discharge feasibility determination process has permitted the relay circuit unit to supply power to the inverter of the electric vehicle.

[0026] According to the above characteristic configuration, even if the hardware of the electric vehicle is not the same as that authenticated, power can be supplied from the facility-side power line to the inverter of the electric vehicle (i.e., charging the vehicle-side storage battery) on the condition that the charge / discharge feasibility determination process permits power supply from the relay circuit unit to the inverter of the electric vehicle.

[0027] Another characteristic feature of the charge / discharge relay device of the present invention is that when the relay side control unit determines in the vehicle determination process that the hardware of the electric vehicle is not the same as that authenticated, the relay side control unit prohibits the relay circuit unit from supplying power to the inverter of the electric vehicle, regardless of whether the charge / discharge feasibility determination process allows the relay circuit unit to supply power to the inverter of the electric vehicle.

[0028] According to the above characteristic configuration, if the hardware of the electric vehicle is not the same as that authenticated, it is possible to prohibit the supply of power from the facility-side power line to the inverter of the electric vehicle (i.e., charging the vehicle-side storage battery), regardless of whether the charge / discharge permission determination process has permitted the supply of power from the relay circuit unit to the inverter of the electric vehicle.

[0029] Another characteristic feature of the charge / discharge relay device of the present invention is that when the relay circuit unit is electrically connected to the inverter of the electric vehicle, the relay side control unit transmits to the electric vehicle a setting value of an automatic voltage adjustment function that adjusts the output voltage from the inverter of the electric vehicle to the relay circuit unit.

[0030] According to the above characteristic configuration, the inverter of the electric vehicle can be made to exhibit an automatic voltage regulation function with an appropriate set value.

[0031] Another characteristic configuration of the charge / discharge relay device according to the present invention is that the relay-side storage unit stores information about software that needs to be stored in the electric vehicle, When the relay circuit unit is electrically connected to the inverter of the electric vehicle, the relay side control unit acquires information about the software stored in the electric vehicle and performs software determination processing to determine whether the required software is stored in the electric vehicle based on the information stored in the relay side memory unit.

[0032] According to the above characteristic configuration, the relay-side control unit can determine whether or not the necessary software is stored in the electric vehicle, that is, whether or not the electric vehicle performs appropriate operations based on appropriate software.

[0033] Another characteristic configuration of the charge / discharge relay device of the present invention is that if the relay side control unit determines in the software determination process that the version of software required for the electric vehicle is not stored, it transmits the software to the electric vehicle.

[0034] According to the above characteristic configuration, the relay-side control unit can transmit the version of software required for the electric vehicle to the electric vehicle. As a result, the electric vehicle can be operated appropriately based on the required version of software. In other words, the electric vehicle can be made to operate appropriately as requested in advance.

[0035] Another characteristic configuration of the charge / discharge relay device of the present invention is that when the relay side control unit determines in the software determination process that the version of software required for the electric vehicle is stored, it allows the supply of power from the inverter of the electric vehicle to the relay circuit unit, provided that the charge / discharge feasibility determination process has permitted the supply of power from the inverter of the electric vehicle to the relay circuit unit.

[0036] According to the above characteristic configuration, when the electric vehicle can operate based on the required version of software, the relay-side control unit can supply power from the inverter of the electric vehicle to the relay circuit unit, provided that the charge / discharge feasibility determination process has permitted the supply of power from the inverter of the electric vehicle to the relay circuit unit. [Brief explanation of the drawings]

[0037] [Figure 1] FIG. 1 is a diagram illustrating a configuration of a system in which a charge / discharge relay device is provided. [Figure 2] 3A and 3B are diagrams illustrating specific configuration examples of a changeover switch and an insulating transformer. [Figure 3] FIG. 1 is a diagram illustrating a configuration of a system in which a charge / discharge relay device is provided. [Figure 4] 10A and 10B are diagrams illustrating examples of charging availability information and discharging availability information. [Figure 5] FIG. 10 is a diagram illustrating the configuration of another system in which a charge / discharge relay device is provided. [Figure 6] FIG. 10 is a diagram illustrating the configuration of another system in which a charge / discharge relay device is provided. [Figure 7] 10A and 10B are diagrams illustrating another example of the chargeability information and the dischargeability information. [Figure 8] FIG. 10 is a diagram illustrating the configuration of another system in which a charge / discharge relay device is provided. DETAILED DESCRIPTION OF THE INVENTION

[0038] First Embodiment A charge / discharge relay device 20 according to a first embodiment of the present invention will be described below with reference to the drawings. 1 and 3 are diagrams illustrating the configuration of a system in which a charge / discharge relay device 20 is installed. As illustrated, the charge / discharge relay device 20 is installed in a facility H, such as a residence or a business office, and electrically connects a facility-side power line 2, which is connected to a power grid 1, to an inverter 42 of an electric vehicle 40, to relay charging to a vehicle-side storage battery 41 of the electric vehicle 40 connected to the inverter 42, and discharging from the vehicle-side storage battery 41. The electric vehicle 40 is, for example, an electric vehicle, a fuel cell vehicle, a plug-in hybrid vehicle, or the like, which is equipped with a vehicle-side storage battery 41 that supplies power to a drive motor that drives the wheels. In FIGS. 1 and 3, paths through which power is supplied are depicted with thick lines, and paths through which power is not supplied are depicted with thin lines.

[0039] The charge / discharge relay device 20 includes a grid-connection protection unit 32, a relay-side control unit 33, a relay-side communication unit 34, a relay-side storage unit 35, and a relay-side storage battery 36.

[0040] Electric vehicle 40 includes a vehicle-side control unit 47, a vehicle-side communication unit 48, and a vehicle-side storage unit 49. Vehicle-side control unit 47 controls the operation of inverter 42.

[0041] Electric vehicle 40 has an AC connection terminal 45 connected to AC circuit unit 43 and a DC connection terminal 46 connected to DC circuit unit 44. When an external charging cable such as connection cable 11 is connected to AC connection terminal 45, vehicle-side storage battery 41 can be charged via the charging cable. Alternatively, vehicle-side storage battery 41 can be charged even when a charging cable is connected to DC connection terminal 46.

[0042] When the connection cable 11 is connected to the AC connection terminal 45, the inverter 42 of the electric vehicle 40 is connected to the facility-side power line 2 via the charge / discharge relay device 20. Then, the inverter 42 of the electric vehicle 40 is used as a grid-connection inverter to connect the vehicle-side storage battery 41 to the power grid 1, and charging and discharging of the vehicle-side storage battery 41 can be performed. In other words, a V2H (Vehicle to Home) system can be built.

[0043] In facility H, a V2H panel 5 and a distribution panel 8 are provided on the facility-side power line 2. A grounding wire 8a provided on the distribution panel 8 and a grounding wire 38 provided on the charge / discharge relay device 20 are connected by a grounding wire 13.

[0044] Power loads 9 and a power supply device 51 are connected to the distribution board 8. The power supply device 51 is a power storage device that can charge and discharge power, or a power generation device equipped with, for example, a fuel cell. The power supply device 51 may be configured to operate so as to cause a reverse flow of power to the power grid 1 (i.e., to supply power upstream of the distribution board 8 (toward the power grid 1)), or may be configured to operate so as not to cause a reverse flow of power to the power grid 1.

[0045] A charge / discharge relay device 20 is connected to the V2H panel 5 via a power wiring 10. Specifically, the charge / discharge relay device 20 is connected to the V2H panel 5 using an interconnection line 10a and a self-sustaining line 10b of the power wiring 10. The interconnection line 10a is connected to a breaker 6 of the V2H panel 5, and the self-sustaining line 10b is connected to a change-over switch 7 of the V2H panel 5.

[0046] The charge / discharge relay device 20 includes a relay circuit unit 21 that electrically connects the facility-side power line 2 and an inverter 42 of the electric vehicle 40. The relay circuit unit 21 is realized using an insulating transformer 22, a changeover switch 23, a switch 24, a grid-connection circuit unit 25, an independent circuit unit 26, a first electric circuit unit 27, and a second electric circuit unit 28, as described below.

[0047] The relay circuit unit 21 constituting the electric circuit inside the charge / discharge relay device 20 is electrically connected to the facility-side power line 2 via a power wiring 10. The relay circuit unit 21 is also electrically connected to an inverter 42 of the electric vehicle 40 via a connection cable 11. In this embodiment, the connection cable 11 has an electric wiring 11a for supplying electric power, a signal line 11b for transmitting information, and a ground wire 11c. One end of the electric wiring 11a of the connection cable 11 is connected to the relay circuit unit 21 inside the charge / discharge relay device 20, and the other end of the electric wiring 11a of the connection cable 11 is connected to a terminal of an electric plug 37. When the terminal of the electric plug 37 is attached to an AC connection terminal 45 of the electric vehicle 40, the relay circuit unit 21 of the charge / discharge relay device 20 and the inverter 42 of the electric vehicle 40 are electrically connected via the electric wiring 11a, and a ground wire 38 provided in the charge / discharge relay device 20 and a ground wire 50 provided in the electric vehicle 40 are electrically connected via the ground wire 11c.

[0048] The relay circuit unit 21 of the charge / discharge relay device 20 is electrically connected to the outside through the interconnection port 29, the self-sustaining port 30, and the connection port 31. Specifically, the relay circuit unit 21 is connected to the interconnection line 10a through the interconnection port 29, to the self-sustaining line 10b through the self-sustaining port 30, and to the electrical wiring 11a of the connection cable 11 through the connection port 31.

[0049] A contact a of the changeover switch 23 is electrically connected to the electrical wiring 11a of the connection cable 11. A contact b of the changeover switch 23 is electrically connected to the isolation transformer 22. A contact c of the changeover switch 23 is electrically connected to one end of the switch 24. The other end of the switch 24 is electrically connected to the interconnection line 10a. The operation of the changeover switch 23 is controlled by the relay-side control unit 33.

[0050] The relay circuit unit 21 has a first electric circuit unit 27 and a second electric circuit unit 28. The first electric circuit unit 27 is configured with an N phase, which is a neutral line, a U phase, which is a voltage line, and a V phase, which are used for electrical connection with the facility-side power line 2. The second electric circuit unit 28 is configured with a U phase, which is a voltage line, and a V phase, which are used for electrical connection with the inverter 42 of the electric vehicle 40. In other words, the first electric circuit unit 27 is configured with a single-phase three-wire system (200V or 100V), and the second electric circuit unit 28 is configured with a single-phase two-wire system (200V). In this embodiment, the connection between the single-phase three-wire first electric circuit unit 27 and the single-phase two-wire second electric circuit unit 28 is made by the changeover switch 23 and the isolation transformer 22.

[0051] The first electrical circuit section 27 has an interconnection circuit section 25 that passes power when the system is in a normal state where power is being supplied normally from the power grid 1, and an independent circuit section 26 that is not electrically connected to the power grid 1 and passes power when the system is not in a normal state (i.e., when an abnormal state occurs).

[0052] FIG. 2 is a diagram showing a specific example of the configuration of the changeover switch 23 and the isolation transformer 22. As shown in the figure, the interconnection line 10a and the isolated line 10b connected to the facility-side power line 2, which is a single-phase three-wire system, are also configured as single-phase three-wire systems. The connection cable 11 is configured as a single-phase two-wire system with a U phase and a V phase. The isolation transformer 22 performs voltage transformation between the single-phase three-wire wiring consisting of the N phase as a neutral line, the U phase as a voltage line, and the V phase as a voltage line, and the single-phase two-wire wiring consisting of the U phase as a voltage line and the V phase as a voltage line. In this way, the changeover switch 23 and the isolation transformer 22 function as a connection unit that connects the single-phase three-wire wiring consisting of the N phase as a neutral line, the U phase as a voltage line, and the V phase as a voltage line, with the single-phase two-wire wiring consisting of the U phase as a voltage line and the V phase as a voltage line.

[0053] The ground wire 38 is connected to the ground wire 13 and the ground wire 11c (11). The ground wire 38 is also connected to the N phase of the self-sustaining circuit section 26.

[0054] The relay-side control unit 33 determines whether or not power is being supplied normally from the power system 1, for example, based on the voltage of the interconnection line 10a at the interconnection port 29. If the power supply from the power system 1 is in a normal state where it is being supplied normally, the relay-side control unit 33 connects the contacts a and c of the changeover switch 23. FIG. 1 is a diagram illustrating the normal state. On the other hand, if the power supply from the power system 1 is in an abnormal state where it is not being supplied normally, the relay-side control unit 33 connects the contacts a and b of the changeover switch 23. FIG. 3 is a diagram illustrating the abnormal state.

[0055] A changeover switch 7 is provided on the V2H panel 5. In a normal state where power is being supplied normally from the power grid 1, contacts a and c of the changeover switch 7 on the V2H panel 5 are connected, as shown in Fig. 1. On the other hand, in an abnormal state where power is not being supplied normally from the power grid 1, contacts a and b of the changeover switch 7 on the V2H panel 5 are connected, as shown in Fig. 3.

[0056] As shown in FIG. 1 , in a normal state (i.e., during grid connection) in which power is being supplied normally from the power grid 1, a distribution panel 8 and a power load 9 are connected to the power grid 1 via a V2H panel 5. An interconnection line 10a is connected to a facility-side power line 2. The interconnection line 10a is also connected to a connection cable 11 via a charge / discharge relay device 20. As a result, power supplied from the power grid 1 can be supplied to the power load 9. The power supplied from the power grid 1 can also be charged into a vehicle-side storage battery 41 via the charge / discharge relay device 20. Alternatively, power discharged from the vehicle-side storage battery 41 can also be supplied to the power load 9 via the charge / discharge relay device 20.

[0057] In this embodiment, the measurement result of the power meter 4, which measures the power at the receiving point of the facility H, is transmitted to the relay-side control unit 33 of the charge / discharge relay device 20. The power meter 4 is configured using, for example, a current transformer (instrument current transformer) used to detect the current value of power supplied from the power system 1 to the V2H panel 5, and can derive the value of the power flowing through the facility-side power line 2 upstream of the V2H panel 5 (on the power system 1 side) from the product of the current value and a predetermined voltage value (e.g., 100 V, 200 V, etc.). Note that the power meter 4 may transmit only the current value of the power in the facility-side power line 2 to the relay-side control unit 33, and the relay-side control unit 33 may derive the power value. The measurement result of the power value is then transmitted to the electric vehicle 40 via the signal line 11b. Information communication between the charge / discharge relay device 20 and the electric vehicle 40 is performed by the relay-side communication unit 34. The operation of the relay-side communication unit 34 is controlled by the relay-side control unit 33. Alternatively, only the current value of the power on the facility-side power line 2 measured by the power measuring instrument 4 may be transmitted from the relay-side control unit 33 to the vehicle-side control unit 47 of the electric vehicle 40, and the vehicle-side control unit 47 may derive the power value.

[0058] In this way, the vehicle-side control unit 47 of the electric vehicle 40 can know the power at the power receiving point of the facility H. The vehicle-side control unit 47 can also control the operation of the inverter 42 so that the discharged power of the vehicle-side storage battery 41 is not reversely flowed to the power grid 1. Note that the vehicle-side control unit 47 may operate the inverter 42 regardless of the power at the power receiving point of the facility H, as long as it is acceptable for the discharged power of the vehicle-side storage battery 41 to be reversely flowed to the power grid 1.

[0059] The relay-side control unit 33 of the charge / discharge relay device 20 receives the measurement results of a power meter 39 that measures the power supplied from the charge / discharge relay device 20 to the electric vehicle 40. In the example shown, the power meter 39 is provided between the selector switch 23 and the connection port 31 of the charge / discharge relay device 20. The power meter 39 is configured using, for example, a current transformer (instrument current transformer) used to detect the current value of the power supplied from the charge / discharge relay device 20 to the electric vehicle 40, and can derive the value of the power supplied from the charge / discharge relay device 20 to the electric vehicle 40 from the product of this current value and a predetermined voltage value. Note that the power meter 39 may transmit only the current value of the power supplied from the charge / discharge relay device 20 to the relay-side control unit 33, and the relay-side control unit 33 may derive the power value. By referring to the measurement results of the power measuring instrument 39, the relay side control unit 33 can determine whether power is being supplied from the relay circuit unit 21 to the electric vehicle 40 (i.e., whether the relay circuit unit 21 is charging the vehicle side storage battery 41 of the electric vehicle 40) or whether power is being supplied from the electric vehicle 40 to the relay circuit unit 21 (i.e., whether the vehicle side storage battery 41 of the electric vehicle 40 is discharging the relay circuit unit 21), and can determine the magnitude of the supplied power.

[0060] For example, in a situation where power is being supplied from the relay circuit unit 21 to the electric vehicle 40 (i.e., a situation where the relay circuit unit 21 is charging the vehicle-side storage battery 41 of the electric vehicle 40), the power meter 39 measures the charging power of the vehicle-side storage battery 41 of the electric vehicle 40. On the other hand, in a situation where power is being supplied from the electric vehicle 40 to the relay circuit unit 21 (i.e., a situation where the vehicle-side storage battery 41 of the electric vehicle 40 is discharging from the relay circuit unit 21), the power meter 39 measures the discharging power of the vehicle-side storage battery 41 of the electric vehicle 40. In other words, if the power measured by the power meter 39 is a positive value, the relay-side control unit 33 can determine that power is being supplied from the relay circuit unit 21 to the electric vehicle 40 (i.e., a situation where the relay circuit unit 21 is charging the vehicle-side storage battery 41 of the electric vehicle 40). On the other hand, if the power measured by the power measuring device 39 is a negative value, the relay side control unit 33 can determine that power is being supplied from the electric vehicle 40 to the relay circuit unit 21 (i.e., that the relay circuit unit 21 is being discharged from the vehicle side storage battery 41 of the electric vehicle 40).

[0061] 3, in an abnormal state where power is not being supplied normally from the power grid 1 (i.e., during an autonomous state), the distribution panel 8 and the power load 9 are connected to the autonomous line 10b via the V2H panel 5. The autonomous line 10b is also connected to the connection cable 11 via the charge / discharge relay device 20. As a result, the power discharged from the vehicle-side storage battery 41 can be supplied to the power load 9 via the charge / discharge relay device 20.

[0062] In this embodiment, the inverter 42 of the electric vehicle 40 is a grid-connected inverter. Therefore, it is necessary to perform grid-connection protection operations, such as overvoltage protection and undervoltage protection, based on, for example, the voltage between the U phase and the N phase and the voltage between the V phase and the N phase. Therefore, the grid-connection protection unit 32 of the charge / discharge relay device 20 performs protection operations (e.g., opening the switch 24) required when connecting the inverter 42 of the electric vehicle 40 to the power grid 1 via the facility-side power line 2, based on the voltage between the U phase and the N phase and the voltage between the V phase and the N phase in the first electric circuit unit 27. For example, the grid-connection protection unit 32 performs overvoltage protection and undervoltage protection based on the voltage between the U phase and the N phase and the voltage between the V phase and the N phase, i.e., by performing two-phase monitoring. That is, the grid-connection protection unit 32 performs protection operations, such as opening the switch 24 when an overvoltage is detected and opening the switch 24 when an undervoltage is detected. The interconnection protection unit 32 can also perform other protection operations such as frequency increase protection operation and frequency decrease protection operation.

[0063] The relay-side storage battery 36 can be charged with power supplied from the facility-side power line 2 and power supplied from the electric vehicle 40, and can supply the charged power to the interconnection protection unit 32. In other words, by including the relay-side storage battery 36 in the charge / discharge relay device 20, the interconnection protection unit 32 can maintain the inverter 42 of the electric vehicle 40 electrically connected to the electric power grid 1 using the power supplied from the relay-side storage battery 36, even when, for example, an instantaneous voltage drop is detected in the electric power grid 1. Furthermore, the interconnection protection unit 32 can perform a protective operation, such as electrically disconnecting the inverter 42 of the electric vehicle 40 from the electric power grid 1, depending on the amount and duration of the voltage drop. The relay-side storage battery 36 can be realized using, for example, various types of storage batteries. The relay-side storage battery 36 does not need to have a large capacity; it only needs to have a capacity sufficient to supply the power required within the charge / discharge relay device 20 for, for example, 10 minutes.

[0064] The vehicle-side storage unit 49 stores information handled by the electric vehicle 40. For example, the vehicle-side storage unit 49 stores information about the hardware and software of the electric vehicle 40. The information about the hardware of the electric vehicle 40 is information such as the chassis number, serial number, and model of the electric vehicle 40. In other words, if information such as the chassis number, serial number, and model of the electric vehicle 40 is known, it is also possible to identify hardware such as the inverter 42 mounted on the electric vehicle 40. The information about the software of the electric vehicle 40 is software for a program that operates the inverter 42, software for implementing flicker countermeasures, etc.

[0065] Electric vehicle 40 is also provided with an inverter 42 that converts DC power to AC power, and an AC circuit unit 43 through which the AC power flows can be connected to facility-side power line 2. In this case, there is no need to provide facility H with a power conversion function that converts DC power to AC power. However, when such a configuration is adopted, inverter 42 of electric vehicle 40 serves as a grid-connection inverter, and therefore it is conceivable that an agreement with the power transmission and distribution company that manages power system 1 will be required to permit only power supply to facility H from an appropriate grid-connection inverter as applied for in advance.

[0066] For example, when the inverter 42 of the electric vehicle 40 is used as a grid-connection inverter and the charge / discharge relay device 20 electrically connects the facility-side power line 2 and the inverter 42 using the relay circuit unit 21 to relay charging to and discharging from the vehicle-side storage battery 41 of the electric vehicle 40 connected to the inverter 42, for example, the hardware of the electric vehicle 40 and the software that realizes its operation must be authenticated in advance. Therefore, if a user of the facility H applies to the power transmission and distribution company that manages the power grid 1 to connect the inverter 42 of the electric vehicle 40 to the power grid 1 via the charge / discharge relay device 20 and the application is approved, the user registers, as authentication information, information about the hardware of the authenticated electric vehicle 40, such as the chassis number, serial number, and model, and the model of the inverter 42, in the relay-side storage unit 35. The user of the facility H may also register various information, such as the setting value of the automatic voltage adjustment function of the inverter 42 of the electric vehicle 40, in the relay-side storage unit 35. For example, a user of facility H registers the information using a computer or the like connected by wire or wirelessly to the charge / discharge relay device 20. As a result, the relay-side storage unit 35 of the charge / discharge relay device 20 stores authentication information about the hardware, such as the vehicle number, serial number and model of the authenticated electric vehicle 40 and the model of the inverter 42, as well as information about the setting values ​​of the automatic voltage adjustment function performed by the inverter 42 of the electric vehicle 40.

[0067] Furthermore, the user of the facility H can store software to be used in the electric vehicle 40 (for example, the above-mentioned software for the program that operates the inverter 42, software for implementing flicker countermeasures, etc.) in the relay-side storage unit 35 using a computer or the like that is connected by wire or wirelessly to the charge / discharge relay device 20. The user of the facility H can also successively update the software stored in the relay-side storage unit 35 to the latest version of the software. In other words, the relay-side storage unit 35 can store information about software that needs to be stored in the electric vehicle 40 (for example, the latest version of the software, etc.).

[0068] Furthermore, it is preferable that information on whether the power supply device 51 and the inverter 42 of the electric vehicle 40 are configured to be electrically connected to each other when connected to the grid and when independent is stored in the relay-side storage unit 35. In the systems of Figures 1 and 3, the power supply device 51 and the inverter 42 of the electric vehicle 40 are configured to be electrically connected to each other when connected to the grid and when independent is stored.

[0069] It is preferable that the above-mentioned information registered in the relay-side memory unit 35 can be confirmed by users of the facility H, the power transmission and distribution business operator that manages the power grid 1, or the like, using, for example, a computer that is connected by wire or wirelessly to the charge and discharge relay device 20, or a display unit provided in the charge and discharge relay device 20 or a display device connected to the charge and discharge relay device 20. With such a configuration, for example, the power transmission and distribution business operator can check whether the inverter 42 of the electric vehicle 40 is properly connected to the power grid via the charge and discharge relay device 20 by looking at the above-mentioned information registered in the relay-side memory unit 35.

[0070] Although a power supply device 51 is connected to the facility-side power line 2 of facility H to which the inverter 42 of electric vehicle 40 is connected, electric vehicle 40 cannot know whether or not the power supply device 51 is connected to the facility-side power line 2. Therefore, if electric vehicle 40 connected to the facility-side power line 2 via inverter 42 is configured to detect the presence or absence of a reverse flow of power from the facility-side power line 2 to the power grid 1 by referring to the measurement results of power meter 4, an abnormal state may occur in which, from the standpoint of electric vehicle 40, even though electric vehicle 40 is not supplying power to the facility-side power line 2, power output from power supply device 51 to the facility-side power line 2 causes a reverse flow of power from the facility-side power line 2 to the power grid 1. In other words, when the vehicle-side storage battery 41 of electric vehicle 40 and the power supply device 51 are interconnected by the facility-side power line 2, it may not be appropriate to allow a reverse flow of power from the vehicle-side storage battery 41 of electric vehicle 40 to the power grid 1.

[0071] Therefore, in the present embodiment, when the inverter 42 of an electric vehicle 40 is connected to the facility-side power line 2 via the relay circuit unit 21 and a power supply device 51 provided in the facility H is connected to the facility-side power line 2, the relay-side storage unit 35 stores charging enable / disable information indicating whether or not to permit power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40 and discharging enable / disable information indicating whether or not to permit power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21, for each combination of one or more types of electric vehicles 40 and one or more types of power supply devices 51 connected to the facility-side power line 2. Note that because the power supply devices 51 are fixedly installed in the facility H, the relay-side storage unit 35 also stores information (e.g., the model of the power supply device 51) that can identify the type of power supply device 51 connected to the facility-side power line 2.

[0072] The relay-side control unit 33 is capable of communicating information with a vehicle-side control unit 47 that controls the operation of the inverter 42 of the electric vehicle 40 via a signal line 11b. The signal line 11b is included in the connection cable 11. Alternatively, the signal line 11b may be realized by a power line (electrical wiring 11a) for realizing power line carrier communication. Furthermore, when the electric plug 37 of the connection cable 11 is attached to the AC connection terminal 45 of the electric vehicle 40, the relay-side control unit 33 can recognize that the relay circuit unit 21 is electrically connected to the inverter 42 of the electric vehicle 40. When the relay circuit unit 21 is electrically connected to the inverter 42 of the electric vehicle 40, the relay-side control unit 33 acquires information capable of identifying the type of the electric vehicle 40 (e.g., the model of the electric vehicle 40) from the vehicle-side control unit 47, and performs a charge / discharge permission determination process to determine whether or not to permit power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40 and whether or not to permit power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21, based on the information capable of identifying the type of the power supply device 51 connected to the facility-side power line 2, the charge permission information, and the discharge permission information. Here, the relay-side control unit 33 prioritizes the result of the charge / discharge permission determination process over the result of the vehicle determination process. In other words, even if the hardware of the electric vehicle 40 is the same as that authenticated, depending on the combination of the electric vehicle 40 and the power supply device 51, the relay-side control unit 33 may not permit (i.e., prohibit) power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21.

[0073] Fig. 4 is a diagram illustrating an example of the chargeability information and the dischargeability information. Fig. 4 shows the chargeability information and the dischargeability information for combinations of type C and type D electric vehicles 40 and type A and type B power supply devices 51. The chargeability information and the dischargeability information also include information that is determined depending on whether the power supply device 51 operates so as not to cause a reverse flow of power to the power grid 1.

[0074] Specifically, the information for combination No. 1A is charging / discharging enable / disable information when a type A power supply device 51 that does not have reverse power flow and a type C electric vehicle 40 are interconnected by the facility-side power line 2. The information indicates that charging of the vehicle-side storage battery 41 of the electric vehicle 40 is permitted when the electric vehicle 40 is connected to the grid (i.e., the relay-side control unit 33 permits power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40), that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is permitted when the electric vehicle 40 is connected to the grid (i.e., permits power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21), and that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is permitted when the electric vehicle 40 is independent (i.e., permits power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21). Note that, because the power supply device 51 does not have reverse power flow, when independent, the vehicle-side storage battery 41 of the electric vehicle 40 can only be discharged, not charged.

[0075] Additionally, the information for combination No. 1B is charging permission / prohibition information and discharging permission / prohibition information when a type A power supply device 51 and a type C electric vehicle 40 that perform reverse power flow are interconnected by the facility-side power line 2. The information indicates that charging of the vehicle-side storage battery 41 of the electric vehicle 40 is permitted when connected to the grid (i.e., the relay-side control unit 33 permits power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40), that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is permitted when connected to the grid (i.e., power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21 is permitted), and that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is not permitted when autonomous (i.e., power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21 is not permitted). Furthermore, since the power supply device 51 has a reverse power flow, if the load power of the power load 9 is small during self-sustaining operation, the vehicle-side storage battery 41 of the electric vehicle 40 can be charged by the reverse power flow from the power supply device 51 (i.e., the relay-side control unit 33 allows power to be supplied from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40).

[0076] Furthermore, when relay circuit unit 21 is electrically connected to inverter 42 of electric vehicle 40, relay-side control unit 33 acquires information about the hardware from electric vehicle 40 and performs vehicle determination processing to determine whether the hardware of electric vehicle 40 is the same as that authenticated, based on the authentication information stored in relay-side storage unit 35. In other words, the vehicle determination processing makes it possible to determine whether the hardware (inverter 42) of electric vehicle 40 has the configuration as previously applied for.

[0077] If the relay-side control unit 33 determines in the vehicle determination process that the hardware of electric vehicle 40 is identical to that authenticated, it permits the supply of power from the inverter 42 of electric vehicle 40 to the relay circuit unit 21, on the condition that the supply of power from the inverter 42 of electric vehicle 40 to the relay circuit unit 21 is permitted by the charge / discharge permission determination process, and if it determines in the vehicle determination process that the hardware of electric vehicle 40 is not identical to that authenticated, it prohibits (i.e., does not permit) the supply of power from the inverter 42 of electric vehicle 40 to the relay circuit unit 21, regardless of whether the supply of power from the inverter 42 of electric vehicle 40 to the relay circuit unit 21 is permitted by the charge / discharge permission determination process. Therefore, it is possible to provide a charge / discharge relay device 20 that can prove that an appropriately configured electric vehicle 40 is grid-connected. For example, if the power measured by the power measuring device 39 is a negative value, the relay side control unit 33 determines that power is being supplied from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21, and closes the switch 24 to prohibit the supply of power from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21.

[0078] If the relay-side control unit 33 determines in the vehicle determination process that the hardware of the electric vehicle 40 is not identical to the authenticated one, the relay circuit unit 21 may permit the supply of power to the inverter 42 of the electric vehicle 40, on the condition that the supply of power from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40 is permitted in the charge / discharge permission determination process. In other words, even if the hardware of the electric vehicle 40 is not identical to the authenticated one, power can be supplied from the facility-side power line 2 to the inverter 42 of the electric vehicle 40 (i.e., charging the vehicle-side storage battery 41). For example, even if a visitor's electric vehicle 40 whose authentication information, etc., is not registered in the relay-side storage unit 35 is connected to the charge / discharge relay device 20 using the connection cable 11, or even if a user of the facility H has just purchased a new or replaced electric vehicle 40 and the authentication information, etc., has not yet been registered in the relay-side storage unit 35, charging the vehicle-side storage battery 41 of the electric vehicle 40, which is necessary for traveling, is permitted.

[0079] If the relay-side control unit 33 determines in the vehicle determination process that the hardware of the electric vehicle 40 is not the same as the authenticated hardware, the relay-side control unit 33 may prohibit the relay circuit unit 21 from supplying power to the inverter 42 of the electric vehicle 40, regardless of whether the charge / discharge permission determination process has permitted the relay circuit unit 21 to supply power to the inverter 42 of the electric vehicle 40. For example, the relay-side control unit 33 can prohibit the relay circuit unit 21 from supplying power to the inverter 42 of the electric vehicle 40 by, for example, opening the switch 24 as described above. The method of prohibiting the relay circuit unit 21 from supplying power to the inverter 42 of the electric vehicle 40 can be changed as appropriate.

[0080] When relay circuit unit 21 is electrically connected to inverter 42 of electric vehicle 40, relay-side control unit 33 transmits to electric vehicle 40, for example, setting values ​​of an automatic voltage regulation function that adjusts the output voltage from inverter 42 of electric vehicle 40 to relay circuit unit 21, which are stored in advance in relay-side storage unit 35 as described above, and the U-phase voltage and V-phase voltage measured by charge / discharge relay device 20. As a result, inverter 42 of electric vehicle 40 executes the automatic voltage regulation function based on the setting values ​​and U-phase voltage and V-phase voltage. In other words, relay-side control unit 33 can cause inverter 42 of electric vehicle 40 to perform the automatic voltage regulation function with appropriate setting values.

[0081] The relay-side storage unit 35 stores information about software that needs to be stored in the electric vehicle 40. When the relay circuit unit 21 is electrically connected to the inverter 42 of the electric vehicle 40, the relay-side control unit 33 acquires information about the stored software (e.g., information about the type of software and its version) from the electric vehicle 40, and performs software determination processing to determine whether or not the necessary software is stored in the electric vehicle 40 based on the information stored in the relay-side storage unit 35. As a result, the relay-side control unit 33 can determine whether or not the necessary software is stored in the electric vehicle 40, i.e., whether or not the electric vehicle 40 performs appropriate operation based on appropriate software.

[0082] Then, when the relay-side control unit 33 determines in the software determination process that the software version required for the electric vehicle 40 is not stored, it transmits the software of the required version to the electric vehicle 40. For example, the software version required for the electric vehicle 40 may be stored in advance in the relay-side storage unit 35, and when the relay-side control unit 33 determines in the software determination process that the software version required for the electric vehicle 40 is not stored, it may read out the software of that version from the relay-side storage unit 35 and transmit it to the electric vehicle 40. As a result, the electric vehicle 40 can be operated appropriately based on the software of the required version. In other words, the electric vehicle 40 can be made to operate appropriately as requested in advance.

[0083] Furthermore, if the relay-side control unit 33 determines in the software determination process that a required version of software is stored for the electric vehicle 40, it permits power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21, on the condition that the charge / discharge permission determination process permits power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21. In other words, if the electric vehicle 40 can operate based on the required version of software, it can allow power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21. On the other hand, if the relay-side control unit 33 determines in the software determination process that a required version of software is not stored for the electric vehicle 40, it may prohibit power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21, regardless of whether the charge / discharge permission determination process permits power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21. For example, the relay-side control unit 33 can prohibit power supply from the inverter 42 of the electric vehicle 40 to the facility-side power line 2, for example, by opening the switch 24. The method for prohibiting the supply of power from the inverter 42 of the electric vehicle 40 to the facility-side power line 2 can be changed as appropriate.

[0084] Second Embodiment In the above embodiment, an example has been described in which the power supply device 51 is connected to the distribution board 8, but the connection destination of the power supply device 51 can be changed as appropriate. Figures 5 and 6 are diagrams showing the configuration of another system in which the charge / discharge relay device 20 is provided. In Figures 5 and 6, paths through which power is supplied are drawn with thick lines, and paths through which power is not supplied are drawn with thin lines.

[0085] In the example shown in FIGS. 5 and 6 , the power supply device 51 is connected to the V2H panel 5 via a breaker 55. The power supply device 51 outputs power to the V2H panel 5 during grid connection, when power is being normally supplied from the power grid 1 to the facility-side power line 2, and outputs power to an independent outlet 52 during an independent state, when power is not being normally supplied from the power grid 1 to the facility-side power line 2. Therefore, in facility H, by connecting the electrical outlet 53 of the power load 54 to the independent outlet 52, power can be supplied from the power supply device 51 to the power load 54 even during an independent state when power is not being normally supplied. That is, in the system shown in FIGS. 5 and 6 , the electric vehicle 40 is not interconnected with the power supply device 51 during independent output ( FIG. 6 ). That is, during an independent state, when the facility-side power line 2 is not connected to the power grid 1, the power supply device 51 and the inverter 42 of the electric vehicle 40 are not electrically connected to each other, and therefore it is not necessary to consider whether a malfunction will occur if the electric vehicle 40 and the power supply device 51 are interconnected. In the case of the systems shown in Figures 5 and 6, the relay side memory unit 35 stores information that the power supply device 51 and the inverter 42 of the electric vehicle 40 are configured to be electrically connected to each other when connected to the grid, and that the power supply device 51 and the inverter 42 of the electric vehicle 40 are configured not to be electrically connected to each other when independent.

[0086] In this case, the charging permission information and the discharging permission information described in the above embodiment include information that is determined depending on whether the power supply device 51 and the inverter 42 of the electric vehicle 40 are electrically connected to each other in an independent state when the facility-side power line 2 is not connected to the power grid 1. In other words, when the power supply device 51 and the inverter 42 of the electric vehicle 40 are not electrically connected to each other in an independent state, it is possible to determine whether or not to permit power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40, and whether or not to permit power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21, without considering whether a malfunction would occur if the power supply device 51 and the inverter 42 of the electric vehicle 40 were interconnected.

[0087] FIG. 7 is a diagram illustrating an example of chargeability information and dischargeability information. In FIG. 7, chargeability information and dischargeability information are shown for a combination of a type C electric vehicle 40 and a type A power supply device 51. In addition, information on whether the electric vehicle 40 is interconnected with the power supply device 51 during standalone output is also included. Note that, for the sake of notation, FIG. 7 uses the same types A and C as those illustrated in FIG. 4, but these are different types of devices.

[0088] Specifically, the information for combination No. 2A is charging / discharging enable / disable information for a case where a type A power supply device 51 that does not allow reverse power flow and a type C electric vehicle 40 are interconnected by the facility-side power line 2, and are not interconnected with the power supply device 51 during standalone output from the electric vehicle 40 (i.e., the cases in FIGS. 5 and 6 ). The information indicates that charging of the vehicle-side storage battery 41 of the electric vehicle 40 is permitted during grid connection (i.e., the relay-side control unit 33 permits power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40), that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is permitted during grid connection (i.e., permits power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21), and that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is permitted during standalone output (i.e., permits power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21). Furthermore, since the power supply device 51 does not have reverse power flow and the electric vehicle 40 and the power supply device 51 are not interconnected when the vehicle is independent, the vehicle-side storage battery 41 of the electric vehicle 40 can only discharge and cannot charge when the vehicle is independent.

[0089] The information for combination No. 2B is charging / discharging enable / disable information in a case where a type A power supply device 51 and a type C electric vehicle 40 that perform reverse power flow are interconnected by the facility-side power line 2, and are not interconnected with the power supply device 51 during standalone output from the electric vehicle 40 (i.e., the cases in FIGS. 5 and 6 ). The information indicates that charging of the vehicle-side storage battery 41 of the electric vehicle 40 is permitted during grid connection (i.e., the relay-side control unit 33 permits power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40), that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is permitted during grid connection (i.e., permits power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21), and that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is permitted during standalone output (i.e., permits power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21). Although the power supply device 51 has reverse power flow, as shown in FIG. 6, the electric vehicle 40 and the power supply device 51 are not interconnected when the vehicle is in an autonomous state, and therefore the vehicle-side storage battery 41 of the electric vehicle 40 can only discharge, but cannot charge, when the vehicle is in an autonomous state.

[0090] The information for combination No. 2C is charging / discharging enable / disable information in a case where a type A power supply device 51 that does not allow reverse power flow and a type C electric vehicle 40 are interconnected by the facility-side power line 2, and are also interconnected with the power supply device 51 during standalone output from the electric vehicle 40 (i.e., the case of FIGS. 1 and 3). The information indicates that charging of the vehicle-side storage battery 41 of the electric vehicle 40 is permitted during grid connection (i.e., the relay-side control unit 33 permits power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40), that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is not permitted during grid connection (i.e., power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21 is not permitted), and that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is permitted during standalone output (i.e., power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21 is permitted). Since the power supply device 51 does not have a reverse power flow, the vehicle-side storage battery 41 of the electric vehicle 40 can only discharge and cannot charge when it is self-sustaining.

[0091] The information for combination No. 2D is charging / discharging enable / disable information in the case where a type A power supply device 51 and a type C electric vehicle 40 that perform reverse power flow are interconnected by the facility-side power line 2, and are also interconnected with the power supply device 51 during standalone output from the electric vehicle 40 (i.e., the cases in FIGS. 1 and 3). The information indicates that charging of the vehicle-side storage battery 41 of the electric vehicle 40 is permitted during grid connection (i.e., the relay-side control unit 33 permits power supply from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40), that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is not permitted during grid connection (i.e., power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21 is not permitted), and that discharging from the vehicle-side storage battery 41 of the electric vehicle 40 is not permitted during standalone output (i.e., power supply from the inverter 42 of the electric vehicle 40 to the relay circuit unit 21 is not permitted). Furthermore, since the power supply device 51 has reverse power flow and the electric vehicle 40 and the power supply device 51 are interconnected during self-sustaining operation, if the load power of the power load 9 is small during self-sustaining operation, it is possible to charge the vehicle-side storage battery 41 of the electric vehicle 40 using reverse power flow from the power supply device 51 (i.e., the relay-side control unit 33 allows power to be supplied from the relay circuit unit 21 to the inverter 42 of the electric vehicle 40).

[0092] <Another embodiment> In the above embodiment, the configuration of the charge / discharge relay device 20 has been described using a specific example, but the configuration can be changed as appropriate. For example, the configuration of the changeover switch 23 has been described specifically in FIG. 2, but the configuration can be changed as appropriate.

[0093] In the above embodiment, information about the hardware of the electric vehicle 40, such as the chassis number, serial number, and model, has been described as an example of authentication information about the hardware of the electric vehicle 40, but other information may also be used as authentication information. For example, the model and serial number of the inverter 42 may also be used as authentication information.

[0094] In the above embodiment, an example has been described in which one power supply device 51 is connected to the facility-side power line 2, but a plurality of power supply devices 51 may be connected to the facility-side power line 2. FIG. 8 is a diagram showing the configuration of another system in which a charge / discharge relay device 20 is provided. In this example, two power supply devices 51 (51A, 51B) are connected to the facility-side power line 2. The power supply device 51A is connected to the facility-side power line 2 at a distribution panel, as shown in FIGS. 1 and 3. The power supply device 51B is connected to the facility-side power line 2 at a V2H panel 5, as shown in FIGS. 5 and 6. In this case, if a combination in which charging is permitted and a combination in which charging is not permitted coexist, the combination in which charging is not permitted takes priority. Furthermore, if a combination in which discharging is permitted and a combination in which discharging is not permitted coexist, the combination in which discharging is not permitted takes priority.

[0095] In the above embodiment, the relay-side control unit 33 may permit power supply from the facility-side power line 2 to the inverter 42 of the electric vehicle 40 even when there is no corresponding combination of electric vehicle 40 and power supply device 51 among the combinations of one or more types of electric vehicle 40 and one or more types of power supply devices 51 connected to the facility-side power line 2 stored in the relay-side storage unit 35, or even when information communication with the vehicle-side control unit 47 is not possible. In this case, the relay-side control unit 33 may permit power supply from the inverter 42 of the electric vehicle 40 to the facility-side power line 2, provided that the power supply device 51 and the inverter 42 of the electric vehicle 40 are configured not to be electrically connected to each other when the facility-side power line 2 is in an autonomous state not connected to the power grid 1 (i.e., the configurations shown in FIGS. 5 and 6 ).

[0096] The configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, as long as no contradictions arise. Furthermore, the embodiments disclosed in this specification are examples, and the embodiments of the present invention are not limited to these and can be modified as appropriate within the scope that does not deviate from the purpose of the present invention. [Industrial Applicability]

[0097] The present invention can be used in a charge / discharge relay device that can properly charge and discharge the vehicle-side battery of an electric vehicle when the vehicle-side battery of the electric vehicle and a power supply device installed in a facility are interconnected by the facility's power line. [Explanation of symbols]

[0098] 1: Power system 2: Facility side power line 4: Power measuring device 20: Charging / discharging relay device 21: Relay circuit section 27: First electrical circuit section 28: Second electrical circuit section 32: Grid protection unit 33: Relay side control unit 35: Relay side memory unit 36: Relay side battery 39: Power measuring instrument 40: Electric vehicles 41: Vehicle battery 42: Inverter 47: Vehicle side control unit 51: Power supply 51A: Power supply 51B: Power supply H: Facility

Claims

1. A charge / discharge relay device that is installed in a facility, electrically connects a facility-side power line that is connected to an electric power grid and an inverter provided in an electric vehicle using a relay circuit unit, and relays charging to and discharging from a vehicle-side storage battery of the electric vehicle that is connected to the inverter, a relay-side storage unit that stores, when the inverter of the electric vehicle is connected to the facility-side power line via the relay circuit unit and a power supply device provided in the facility is connected to the facility-side power line, charging enable / disable information indicating whether or not power supply from the relay circuit unit to the inverter of the electric vehicle is permitted, and discharging enable / disable information indicating whether or not power supply from the inverter of the electric vehicle to the relay circuit unit is permitted, for each combination of one or more types of the electric vehicle and one or more types of the power supply device connected to the facility-side power line; a relay-side control unit capable of communicating information with a vehicle-side control unit that controls the operation of the inverter of the electric vehicle; When the relay circuit unit is electrically connected to the inverter of the electric vehicle, the relay-side control unit acquires information capable of identifying the type of the electric vehicle from the vehicle-side control unit, and performs a charge / discharge enable / disable determination process of determining whether or not to permit power supply from the relay circuit unit to the inverter of the electric vehicle and whether or not to permit power supply from the inverter of the electric vehicle to the relay circuit unit, based on the information capable of identifying the type of the power supply device connected to the facility-side power line, the charge enable / disable information, and the discharge enable / disable information.

2. The charge / discharge relay device according to claim 1 , wherein the charge / discharge enable / disable information and the discharge / discharge enable / disable information include information determined depending on whether the power supply device operates so as not to cause a reverse flow of power to the power grid.

3. 3. The charge / discharge relay device according to claim 1, wherein the charging availability information and the discharging availability information include information determined depending on whether the power supply device and the inverter of the electric vehicle are electrically connected to each other in an autonomous state in which the facility-side power line is not connected to the power grid.

4. a first electric circuit unit configured with an N-phase neutral line, a U-phase voltage line, and a V-phase voltage line, which are used for electrically connecting to the facility-side power line; a second electric circuit unit configured with a U-phase voltage line and a V-phase voltage line, the second electric circuit unit being used for electrically connecting to the inverter of the electric vehicle; 2. The charge / discharge relay device according to claim 1, further comprising: a grid connection protection unit that performs a protective operation required when the inverter of the electric vehicle is connected to the power grid via the facility-side power line, based on a voltage between a U phase and an N phase and a voltage between a V phase and an N phase in the first electric circuit unit.

5. 5. The charge / discharge relay device according to claim 4, further comprising a relay-side storage battery capable of being charged with power supplied from the facility-side power line and power supplied from the electric vehicle, and capable of supplying the charged power to the interconnection protection unit.

6. The charge / discharge relay device according to claim 4 or 5, wherein a measurement result of a power meter that measures power at a receiving point of the facility is transmitted to the electric vehicle.

7. 6. The charge / discharge relay device according to claim 4 or 5, further comprising a connection section that connects an N-phase neutral line, a U-phase voltage line, and a V-phase voltage line that constitute the first electrical circuit section with a U-phase voltage line and a V-phase voltage line that constitute the second electrical circuit section.

8. 6. The charge / discharge relay device according to claim 4, wherein the relay-side control unit allows power supply from the facility-side power line to the inverter of the electric vehicle even when a corresponding combination of the electric vehicle and the power supply device does not exist or when information communication with the vehicle-side control unit is not possible.

9. the relay-side storage unit stores authentication information about hardware included in the authenticated electric vehicle; The relay side control unit When the relay circuit unit is electrically connected to the inverter of the electric vehicle, information about the hardware is acquired from the electric vehicle, and a vehicle determination process is performed to determine whether the hardware of the electric vehicle is identical to the authenticated hardware based on the authentication information stored in the relay-side storage unit; When it is determined in the vehicle determination process that the hardware of the electric vehicle is identical to that authenticated, permitting the supply of power from the inverter of the electric vehicle to the relay circuit unit on the condition that the supply of power from the inverter of the electric vehicle to the relay circuit unit is permitted in the charge / discharge permission determination process; 2. The charge / discharge relay device according to claim 1, wherein, when the vehicle determination process determines that the hardware of the electric vehicle is not the same as that authenticated, the charge / discharge relay device prohibits the supply of power from the inverter of the electric vehicle to the relay circuit unit, regardless of whether the charge / discharge feasibility determination process permits the supply of power from the inverter of the electric vehicle to the relay circuit unit.

10. 10. The charge / discharge relay device according to claim 9, wherein, when the relay side control unit determines in the vehicle determination process that the hardware of the electric vehicle is not the same as that authenticated, the relay side control unit permits the supply of power from the relay circuit unit to the inverter of the electric vehicle, on the condition that the supply of power from the relay circuit unit to the inverter of the electric vehicle is permitted by the charge / discharge feasibility determination process.

11. 10. The charge / discharge relay device according to claim 9, wherein, when the relay side control unit determines in the vehicle determination process that the hardware of the electric vehicle is not the same as that authenticated, the relay side control unit prohibits the relay circuit unit from supplying power to the inverter of the electric vehicle, regardless of whether the charge / discharge feasibility determination process permits the relay circuit unit to supply power to the inverter of the electric vehicle.

12. The charge / discharge relay device according to any one of claims 9 to 11, wherein the relay side control unit transmits to the electric vehicle a setting value of an automatic voltage adjustment function that adjusts the output voltage from the inverter of the electric vehicle to the relay circuit unit when the relay circuit unit is electrically connected to the inverter of the electric vehicle.

13. the relay-side storage unit stores information about software that needs to be stored in the electric vehicle; The charge / discharge relay device according to any one of claims 9 to 11, wherein when the relay circuit unit is electrically connected to the inverter of the electric vehicle, the relay side control unit acquires information about the software stored in the electric vehicle, and performs software determination processing to determine whether the necessary software is stored in the electric vehicle based on the information stored in the relay side memory unit.

14. 14. The charge / discharge relay device according to claim 13, wherein the relay-side control unit transmits the software to the electric vehicle when it determines in the software determination process that a version of software required for the electric vehicle is not stored.

15. 14. The charge / discharge relay device according to claim 13, wherein when the relay side control unit determines in the software determination process that a version of software required for the electric vehicle is stored, the relay side control unit permits the supply of power from the inverter of the electric vehicle to the relay circuit unit, on the condition that the supply of power from the inverter of the electric vehicle to the relay circuit unit is permitted in the charge / discharge feasibility determination process.

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