Power supply system

Abstract

To provide a power supply system capable of effectively utilizing a device having a power supply function.SOLUTION: A power supply system comprises: a power conditioner 12; a switching board 3; a system-side electric outlet 8a which is connected to a first voltage line and a neural line of a power line 4 and is not connected to a second voltage line; and a system-side electric plug 20 which is connected to an electric cable 21 connected to the power conditioner 12, and is connectable to an electric outlet capable of supplying power. A power generation device 9 is an AC 100 V power source connected to the first voltage line and the neutral line constituting the power line 4, a power supply to the power line 4 is regulated so as not to supply power from the power line 4 to the switching board 3 which is provided at an upstream side of the power line 4, and the system-side electric plug 20 can be connected to the system-side electric outlet 8a.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a power supply system including a power generation device and a charge / discharge device. [Background technology]

[0002] Patent Document 1 (Japanese Patent No. 6289661) describes a power supply system including a power generation device (23) and a charge / discharge device (storage battery 12). In this power supply system, the power generation device (23) is configured to generate power while the current sensor (40) detects a forward power flow during grid-connected operation in which power is normally supplied from the power grid. In other words, the power generated by the power generation device (23) is limited to less than the power consumption of the load. In addition, in this power supply system, during stand-alone operation in which power is not normally supplied from the power grid, surplus power of the power generation device (23) can be charged to the charge / discharge device (12) via a route that does not go through the current sensor (40).

[0003] Patent Document 2 (Japanese Patent No. 6351351) describes a power supply system to which a storage battery of an electric vehicle can be connected. While the storage battery of the electric vehicle is connected to the power supply system, AC power from the commercial grid can be converted into DC power to charge the storage battery of the electric vehicle, and DC power from the storage battery of the electric vehicle can be converted into AC power and output to the house side (power supply system side). In this way, the power supply system described in Patent Document 2 can receive power from the storage battery of the electric vehicle when power is needed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6289661 [Patent Document 2] Patent No. 6351351 Summary of the Invention [Problem to be solved by the invention]

[0005] Although a V2H (Vehicle to Home) system such as that described in Patent Document 2 is convenient, there is a problem in that the device for bidirectionally exchanging power between the electric vehicle and the power supply system is expensive.

[0006] In addition to electric vehicles, fuel cell vehicles, plug-in hybrid vehicles, and the like, there are many other vehicles equipped with electrical outlets capable of outputting AC power. Furthermore, there are many portable power generation devices and power storage devices equipped with electrical outlets capable of outputting AC power. Therefore, it would be preferable to be able to receive AC power from these vehicles and devices when the power supply system runs short of power.

[0007] The present invention has been made in consideration of the above problems, and has an object to provide a power supply system that can effectively utilize a device having a power supply function. [Means for solving the problem]

[0008] A characteristic configuration of a power supply system according to the present invention for achieving the above object is a power supply system including a power generation device, a charge / discharge device, and a single-phase three-wire power line having a first voltage line, a second voltage line, and a neutral line, A power conditioner to which the charging / discharging device is connected; A switching panel that switches between an interconnected connection state in which the power line to which the power generation device and the power load are connected is electrically connected to both the power grid and the power conditioner, and an independent connection state in which the power line is electrically connected to the power conditioner and is not electrically connected to the power grid; a system-side electrical outlet connected to the first voltage line and the neutral line of the power line and not connected to the second voltage line; a system-side electric plug that is connected to an electric cable that is connected to the power conditioner and that is connectable to an electric outlet that can supply electric power; the power generation device is an AC 100V power supply connected to the first voltage line and the neutral line constituting the power line, and adjusts the power supply to the power line so that power is not supplied from the power line to the switching panel provided upstream of the power line; The system-side electrical plug is configured to be connectable to the system-side electrical outlet.

[0009] According to the above characteristic configuration, when the system-side electric plug is connected to an electric outlet capable of supplying electric power, the power conditioner connected to the electric cable connected to the system-side electric plug can receive electric power from the electric outlet. For example, the power conditioner can receive electric power from a vehicle equipped with an electric outlet, or a portable power generation device and power storage device equipped with an electric outlet. As a result, a charging / discharging device connected to the power conditioner can be charged with the electric power supplied from the electric outlet. In this characteristic configuration, since the power generation device adjusts the power supply to the power line so that power is not supplied from the power line to the switching panel provided upstream of the power line, power cannot be supplied from the power generation device to the charging / discharging device via the power line and the switching panel. However, in this characteristic configuration, when the system side electric plug is connected to the system side electric outlet connected to the power line, the charging / discharging device connected to the power conditioner can be charged with power supplied from the power line.

[0010] Furthermore, in this characteristic configuration, the power generation device and the system-side electrical outlet are both connected to the first voltage line and the neutral line that constitute the power line. In other words, in a three-phase single-wire power line, the phase to which the power generation device supplies power is the same as the phase to which the power is taken out from the system-side electrical outlet, for example, to a power conditioner. As a result, power imbalance is unlikely to occur between the phases of the power line. Therefore, it is possible to provide a power supply system that can effectively utilize devices having a power supply function.

[0011] Another characteristic feature of the power supply system according to the present invention is that the length of the electric cable is such that the system side electric plug can be connected to the system side electric outlet.

[0012] According to the above characteristic configuration, the system-side electric plug can be securely connected to the system-side electric outlet.

[0013] In another aspect of the power supply system according to the present invention, the system-side electrical outlet is connected to the power line via a breaker, The power conditioner limits the current flowing through the electric cable to a predetermined current or less that is smaller than the rated current of the breaker.

[0014] According to the above characteristic configuration, it is possible to prevent a large current from continuously flowing through the breaker.

[0015] Another characteristic configuration of the power supply system according to the present invention is a power supply system including a power generation device, a charge / discharge device, and a single-phase three-wire power line having a first voltage line, a second voltage line, and a neutral line, A power conditioner to which the charging / discharging device is connected; A switching panel that switches between an interconnected connection state in which the power line to which the power generation device and the power load are connected is electrically connected to both the power grid and the power conditioner, and an independent connection state in which the power line is electrically connected to the power conditioner and is not electrically connected to the power grid; A power supply switch connected to the power conditioner; a system-side electric plug connected to an electric cable connected to the power supply switch and connectable to an electric outlet capable of supplying electric power; a connection line connected to the first voltage line and the neutral line of the power line, the connection line connecting the power supply switch and the power line; the power generation device is an AC 100V power supply connected to the first voltage line and the neutral line constituting the power line, and adjusts the power supply to the power line so that power is not supplied from the power line to the switching panel provided upstream of the power line; The power supply switch is configured to switch to a first connection state in which the power conditioner is electrically connected to the connecting line and the power conditioner is not electrically connected to the electrical cable when the system side electrical plug is not connected to the electrical outlet and power is not supplied to the electrical cable, and to switch to a second connection state in which the power conditioner is electrically connected to the electrical cable and the power conditioner is not electrically connected to the connecting line when the system side electrical plug is connected to the electrical outlet and power is supplied to the electrical cable.

[0016] According to the above characteristic configuration, when the system-side electric plug is connected to an electric outlet and electric power is supplied to the electric cable, the power supply switch switches to a second connection state in which the power conditioner and the electric cable are electrically connected. That is, the power conditioner connected to the electric cable connected to the system-side electric plug can receive electric power from the electric outlet. For example, the power conditioner can receive electric power from a vehicle equipped with an electric outlet, or a portable power generation device and power storage device equipped with an electric outlet. As a result, a charging / discharging device connected to the power conditioner can be charged with the electric power supplied from the electric outlet. In this characteristic configuration, the power generation device adjusts the power supply to the power line so that power is not supplied from the power line to the switching panel provided upstream of the power line, so power cannot be supplied from the power generation device to the charge / discharge device via the power line and the switching panel. However, in this characteristic configuration, when the system-side electric plug is not connected to the electric outlet and power is not being supplied to the electric cable, the power supply switching device switches to a first connection state in which the power conditioner is electrically connected to the connection line connected to the power line. In other words, the charge / discharge device connected to the power conditioner can be charged with power supplied from the power line.

[0017] Furthermore, in this characteristic configuration, the power generation device and the connection line are both connected to the first voltage line and the neutral line that constitute the power line. That is, in a three-phase single-wire power line, the phase to which the power generation device supplies power is the same as the phase to which power is taken from the connection line, for example, via a power supply switch, to a power conditioner. As a result, power imbalance is unlikely to occur between the phases of the power line. Therefore, it is possible to provide a power supply system that can effectively utilize devices having a power supply function.

[0018] In another characteristic configuration of the power supply system according to the present invention, the connection line is connected to the power line via a breaker, The power conditioner limits the current flowing through the power supply switching device to a predetermined current or less that is smaller than the rated current of the breaker.

[0019] According to the above characteristic configuration, it is possible to prevent a large current from continuously flowing through the breaker.

[0020] Another characteristic configuration of the power supply system according to the present invention is that, when the power grid goes from an abnormal state in which the power grid does not normally supply power to the switching board to a normal state in which the power grid normally supplies power to the switching board, after a first predetermined period has elapsed, the switching board switches from the independent connection state to the grid connection state; When the power grid changes from the abnormal state to the normal state, the power conditioner stops inputting and outputting power for a second predetermined period that is equal to or longer than the first predetermined period; When the input of power from the power line to the power generation device is stopped for a third specified period shorter than the second specified period, the power generation device stops supplying power to the power line while the input of power from the power line to the power generation device is stopped and for the second specified period after the input of power from the power line to the power generation device begins.

[0021] According to the above characteristic configuration, when the power system goes from an abnormal state to a normal state, the switchboard switches from the independent connection state to the grid connection state after the first predetermined period has elapsed, and the power conditioner stops the input and output of power for a second predetermined period. In other words, even if the power system goes from an abnormal state to a normal state, the power line is electrically connected to the power conditioner and the power line is not electrically connected to the power system until the first predetermined period has elapsed, and the supply of power from the power conditioner to the power line is stopped for a second predetermined period. Therefore, the power generation device detects that the input of power from the power line to the power generation device has been stopped for a third predetermined period. Then, the power generation device stops the supply of power from the power generation device to the power line while the input of power from the power line to the power generation device has been stopped and for a second predetermined period after the input of power from the power line to the power generation device has started. In this way, when the power system goes from an abnormal state to a normal state, the power conditioner stops inputting and outputting power for a second predetermined period, and the power generation device stops supplying power to the power line for the second predetermined period from when the input of power from the power line to the power generation device begins. As a result, when the power system goes from an abnormal state to a normal state, it is possible to reliably provide a period during which the power conditioner and the power generation device do not supply power to the power line. [Brief description of the drawings]

[0022] [Figure 1] 1 is a diagram showing a configuration of a power supply system according to a first embodiment. [Diagram 2]1 is a diagram showing a configuration of a power supply system according to a first embodiment. [Diagram 3] 1 is a diagram showing a configuration of a power supply system according to a first embodiment. [Figure 4] 1 is a diagram showing a configuration of a power supply system according to a first embodiment. [Diagram 5] 1 is a diagram showing a configuration of a power supply system according to a first embodiment. [Figure 6] 1 is a diagram showing a configuration of a power supply system according to a first embodiment. [Figure 7] FIG. 11 is a diagram showing a configuration of a power supply system according to a second embodiment. [Figure 8] FIG. 11 is a diagram showing a configuration of a power supply system according to a second embodiment. [Figure 9] FIG. 11 is a diagram showing a configuration of a power supply system according to a second embodiment. [Figure 10] FIG. 13 is a diagram showing a configuration of a power supply system according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] First Embodiment A power supply system according to a first embodiment of the present invention will be described below with reference to the drawings. 1 to 6 are diagrams showing the configuration of a power supply system according to a first embodiment. As shown in the drawings, the power supply system includes a power generation device 9, a charge / discharge device 19, and a single-phase three-wire power line 4 having a first voltage line, a second voltage line, and a neutral line. In addition, the power supply system includes a power conditioner 12, a switching panel 3, a system-side electric outlet 8, and a system-side electric plug 20. In the following embodiments, the first voltage line of the power line 4 may be referred to as the U-phase, the second voltage line as the V-phase, and the neutral line as the N-phase. The power supply system is installed in a facility such as a residence or a business office.

[0024] The power conditioner 12 is connected to the switchboard 3, the solar cell device 18, the charge / discharge device 19, and an electric cable 21 connected to a system-side electric plug 20. Specifically, the power conditioner 12 includes a DC / DC conversion unit 15 to which the solar cell device 18 is connected, a DC / DC conversion unit 16 to which the charge / discharge device 19 is connected, and an input power conversion unit 17 to which the electric cable 21 is connected. In addition, the power conditioner 12 includes an inverter 14 connected to the DC / DC conversion unit 15, the DC / DC conversion unit 16, and the input power conversion unit 17 to convert the DC power into AC power, and a switch 13 connected to the AC side of the inverter 14. The switch 13 has a contact a connected to the AC side of the inverter 14, a contact b connected to the grid connection line 5, and a contact c connected to the independent connection line 6.

[0025] The system-side electric plug 20 connected to the electric cable 21 can be connected to an electric outlet (not shown) provided in a portable power supply device 22 capable of supplying electric power. When the system-side electric plug 20 is electrically connected to the electric outlet of the power supply device 22, the power conditioner 12 can receive electric power from the power supply device 22 via the input power conversion unit 17.

[0026] Power supply device 22 is a portable power generation device or power storage device equipped with an electrical outlet capable of outputting electric power, etc. For example, power supply device 22 may be a vehicle (e.g., an electric vehicle, a fuel cell vehicle, a hybrid vehicle, etc.) equipped with a power generation device or a power storage device having an electrical outlet capable of outputting electric power.

[0027] The switching panel 3 switches between an interconnected connection state (FIG. 1) in which the power line 4, to which the power generation device 9 and the power load 7 are connected, is electrically connected to both the power system 1 and the power conditioner 12, and an independent connection state (FIGS. 2 and 3) in which the power line 4 (distribution panel) is electrically connected to the power conditioner 12 and is not electrically connected to the power system 1. That is, in the case of the interconnected connection state shown in FIG. 1, the switching panel 3 electrically connects the power system 1 and the power line 4, electrically connects the power system 1 and the power conditioner 12, and electrically connects the power line 4 and the power conditioner 12. In addition, in the case of the independent connection state shown in FIG. 2, the switching panel 3 cuts off the electrical connection between the power system 1 and the power line 4, cuts off the electrical connection between the power system 1 and the power conditioner 12, and electrically connects the power line 4 and the power conditioner 12.

[0028] Specifically, the switch panel 3 is connected to the power system 1 via the service line 2. The switch panel 3 and the power conditioner 12 are connected by an interconnection line 5 and an independent connection line 6. The switch panel 3 also includes a changeover switch 3c. A contact a of the changeover switch 3c is connected to the power line 4. A contact b of the changeover switch 3c is connected to the service line 2 connected to the power system 1, a breaker 3d connected to the interconnection line 5, and a delay timer circuit 3b.

[0029] The changeover switch 3c is switched to either a state where the contact a and the contact b are connected (grid connection state) or a state where the contact a and the contact c are connected (independent connection state). In this embodiment, when power is supplied to the electromagnetic coil 3a, the changeover switch 3c is switched to the grid connection state by the electromagnetic force, and when power is not supplied to the electromagnetic coil 3a, the changeover switch 3c is switched to the independent connection state.

[0030] The delay timer circuit 3b is electrically connected to the contact b of the changeover switch 3c, and can receive power from at least one of the power system 1 and the interconnection line 5. The delay timer circuit 3b supplies power to the electromagnetic coil 3a after a first predetermined period has elapsed since the power supply is started. In other words, when the power system 1 goes from an abnormal state (such as a power outage) in which the power system 1 does not normally supply power to the switch panel 3 to a normal state in which the power system 1 normally supplies power, the changeover switch 3c switches from an independent connection state (a state in which the contact a and the contact c are connected) to an interconnection state (a state in which the contact a and the contact b are connected) after a first predetermined period has elapsed since that point.

[0031] A power generation device 9, power loads 7 (7a, 7b), and system-side electrical outlets 8 (8a, 8b) are connected to the power line 4 via breakers 11, respectively.

[0032] The power generating device 9 is a 100V AC power source connected to a first voltage line (U-phase) and a neutral line (N-phase) constituting the power line 4. For example, the power generating device 9 is a fuel cell device, or a device including an engine and a generator driven by the engine. Also, a power measuring unit 10 is provided that measures the power flowing through a portion upstream (on the power system 1 side) of a connection point P1 of the power generating device 9 to the power line 4 and transmits the measurement result to the power generating device 9. The power generating device 9 can adjust the power it supplies to the power line 4. For example, the power generating device 9 can perform an operation of outputting rated power to the power line 4, or an operation of adjusting the generated power so that the power measured by the power measuring unit 10 does not become reverse flow power, i.e., so that the power supplied by the power generating device 9 does not flow toward the upstream switchboard 3.

[0033] The power load 7a is a 100V load connected to the first voltage line (U phase) and neutral line (N phase) that make up the power line 4. The power load 7b is a 100V load connected to the second voltage line (V phase) and neutral line (N phase) that make up the power line 4.

[0034] The system-side electrical outlet 8a is an electrical outlet for a 100V load that is connected to the first voltage line (U phase) and neutral line (N phase) that make up the power line 4. In other words, the system-side electrical outlet 8a is an electrical outlet that is connected to the first voltage line and neutral line of the power line 4, but is not connected to the second voltage line. The system-side electrical outlet 8b is an electrical outlet for a 100V load that is connected to the second voltage line (V phase) and neutral line (N phase) that make up the power line 4.

[0035] FIG. 1 is a diagram showing a normal state in which the power system 1 normally supplies power to the switching panel 3. In the figure, the parts where power is being supplied are indicated by thick lines. As shown in the figure, since power is being normally supplied from the power system 1, the delay timer circuit 3b of the switching panel 3 is in a state in which power is being supplied to the electromagnetic coil 3a. Therefore, the changeover switch 3c is switched to a state in which the contact a and the contact b are connected. In addition, since the breaker 3d is in a closed operation (conducting state), the voltage of the power supplied from the power system 1 is also transmitted to the power conditioner 12 via the interconnection line 5. As a result, the switching panel 3 is in an interconnection state in which the power line 4 to which the power generation device 9 and the power load 7 are connected is electrically connected to both the power system 1 and the power conditioner 12.

[0036] The power conditioner 12 can recognize that the power supply from the power system 1 is normal via the interconnection line 5, and therefore switches the switch 13 to a state in which contact a and contact b are connected. Note that the input power conversion unit 17 performs an operation of receiving an input of power from the electric cable 21 (power input operation) only when the system-side electric plug 20 is connected to an electric outlet of the power supply device 22 and a voltage is input.

[0037] 2 and 3 are diagrams showing an abnormal state in which the power system 1 does not normally supply power to the switching panel 3. In the diagrams, the locations where power is being supplied are indicated by thick lines. Specifically, FIG. 2 is a diagram showing a state in which the system-side electric plug 20 is connected to the system-side electric outlet 8a (i.e., an electrically connected state). FIG. 3 is a diagram showing a state in which the system-side electric plug 20 is connected to the electric outlet of the power supply device 22 (i.e., an electrically connected state).

[0038] As shown in FIG. 2 and FIG. 3, power is not normally supplied from the power system 1, so power is not supplied to the electromagnetic coil 3a of the switching panel 3. Therefore, the changeover switch 3c is switched to a state in which the contact a and the contact c are connected. The fact that power is no longer supplied from the power system 1 is also transmitted to the power conditioner 12 via the interconnection connection line 5. Then, the power conditioner 12 can recognize that the power supply from the power system 1 is not normally performed, so it switches the switch 13 to a state in which the contact a and the contact c are connected. As a result, the power conditioner 12 inputs and outputs power via the independent connection line 6. The switching panel 3 switches to an independent connection state in which the power line 4 is electrically connected to the power conditioner 12 and the power line 4 is not electrically connected to the power system 1.

[0039] In the example shown in Fig. 2, the system-side electric plug 20 is configured so as to be connectable to a system-side electric outlet 8 (8a, 8b) capable of supplying electric power. In particular, the system-side electric plug 20 is configured so as to be connectable to the system-side electric outlet 8a which is connected to the same phases (U-phase and N-phase) to which the power generation device 9 is connected, and in Fig. 2, the system-side electric plug 20 is actually connected to the system-side electric outlet 8a.

[0040] In this embodiment, the length of the electric cable 21 is such that the system-side electric plug 20 can be connected to the system-side electric outlet 8a. It is also preferable that there is a mark around the system-side electric outlet 8a indicating that the system-side electric outlet 8a is an electric outlet for connecting the system-side electric plug 20. It is also preferable that there is a mark in an instruction manual or the like referred to by facility users indicating that the system-side electric outlet 8a is an electric outlet for connecting the system-side electric plug 20.

[0041] When power is input to the input power conversion unit 17, the power conditioner 12 is configured to receive power from the electric cable 21 via the input power conversion unit 17. That is, in the example shown in Fig. 2, the power conditioner 12 can receive power from the power line 4 via the input power conversion unit 17, the electric cable 21, the system side electric plug 20, and the system side electric outlet 8a.

[0042] In particular, in the example shown in FIG. 2, the system side electric plug 20 connected to the input power conversion unit 17 of the power conditioner 12 is connected to the system side electric outlet 8a connected to the same phase (U phase and N phase) as the phase to which the power generation device 9 is connected. Therefore, the power supplied from the power generation device 9 to the power line 4 is input to the power conditioner 12 via the system side electric outlet 8a, the system side electric plug 20, and the electric cable 21, and the power is charged, for example, to the charge / discharge device 19. In this way, the power generation device 9 and the system side electric outlet 8a are both connected to the first voltage line (U phase) and the neutral line (N phase) constituting the power line 4. That is, in the three-phase single-wire power line 4, the phase to which the power generation device 9 supplies power is the same as the phase to which power is taken out from the system side electric outlet 8a to, for example, the power conditioner 12. As a result, power imbalance between the phases of the power line 4 is less likely to occur.

[0043] 3, the system-side electric plug 20 is connected to an electric outlet (not shown) of the power supply device 22. Therefore, the power conditioner 12 can receive power from the power supply device 22 via the input power conversion unit 17, the electric cable 21, and the system-side electric plug 20. Then, the power supplied from the power supply device 22 is input to the power conditioner 12 via the system-side electric plug 20 and the electric cable 21, and the power is charged in the charge / discharge device 19, for example.

[0044] The power conditioner 12 may limit the current flowing through the electric cable 21 to a predetermined current or less that is smaller than the rated current of the breaker 11 (for example, a current of 30% of the rated current or less). By limiting in this way, the current flowing through one breaker 11 to which the electric cable 21 is connected becomes a predetermined current or less that is sufficiently smaller than the rated current, and it is possible to prevent a large current from continuing to flow through the breaker 11. For example, if the rated current of the breaker 11 is 20 A and the power conditioner 12 is set to limit the current flowing through the electric cable 21 to 30% of the rated current of the breaker 11, the current flowing through the electric cable 21 will be 6 A (=20 A×0.3).

[0045] As described above, when the system-side electric plug 20 is connected to an electric outlet capable of supplying electric power, the power conditioner 12 connected to the electric cable 21 connected to the system-side electric plug 20 can receive a supply of electric power from the electric outlet. For example, the power conditioner 12 can receive a supply of electric power from a power source device 22 such as a vehicle equipped with an electric outlet or a portable power generation device and power storage device equipped with an electric outlet. As a result, the charge / discharge device 19 connected to the power conditioner 12 can be charged with the electric power supplied from the electric outlet.

[0046] In this embodiment, the power generation device 9 adjusts the power supply to the power line 4 so that power is not supplied from the power line 4 to the switching panel 3 provided upstream of the power line 4, and therefore power cannot be supplied from the power generation device 9 to the charging / discharging device 19 via the power line 4 and the switching panel 3. However, when the system side electric plug 20 is connected to the system side electric outlet 8 connected to the power line 4, the charging / discharging device 19 connected to the power conditioner 12 can be charged with power supplied from the power line 4 (for example, power generated by the power generation device 9).

[0047] Next, with reference to Figs. 4 to 6, the operation of the power supply system after the power supply from the power system 1 has returned to normal (ie, after power has been restored) will be described. FIG. 4 is a diagram showing a state immediately after the power grid 1 has shifted from the independent state shown in FIG. 2 to a state in which power has been restored. In this example, power is normally supplied from the power grid 1 to the switchboard 3, so power is also supplied to the delay timer circuit 3b. However, the delay timer circuit 3b does not immediately supply power to the electromagnetic coil 3a, but supplies power to the electromagnetic coil 3a after a first predetermined period (e.g., 2 seconds) has elapsed. Therefore, at the time shown in FIG. 4, power is not being supplied to the electromagnetic coil 3a. Therefore, the changeover switch 3c is in a state in which the contact a and the contact c are connected.

[0048] Moreover, since the power supply from the power system 1 to the switching panel 3 is performed normally, power is also supplied to the power conditioner 12 via the interconnection line 5. That is, the power conditioner 12 can recognize that the power system 1 has changed from an abnormal state to a normal state. Then, when the power system 1 has changed from an abnormal state to a normal state, the power conditioner 12 stops the input / output of power for a second predetermined period (for example, 300 seconds) that is equal to or longer than the first predetermined period. Specifically, the power conditioner 12 stops the input / output of power between the interconnection line 5 and the independent connection line 6, stops the input of power from the solar cell device 18, stops the input / output of power between the charging / discharging device 19, and stops the input of power from the input power conversion unit 17. Specifically, the power conditioner 12 stops the operations of the inverter 14, the DC / DC conversion unit 15, the DC / DC conversion unit 16, and the input power conversion unit 17.

[0049] Therefore, in the state shown in FIG. 4, no power is supplied to the power line 4. Therefore, the power generating device 9 can recognize that no power is being supplied to the power line 4, that is, that a power outage has occurred. For example, when the input of power from the power line 4 to the power generating device 9 is stopped for a third predetermined period (for example, 1 second), the power generating device 9 determines that a power outage has occurred on the power line 4. Then, when the input of power from the power line 4 to the power generating device 9 is stopped for a third predetermined period (for example, 1 second) that is shorter than the above-mentioned first predetermined period (for example, 2 seconds), the power generating device 9 stops supplying power from the power generating device 9 to the power line 4 while the input of power from the power line 4 to the power generating device 9 is stopped and for a second predetermined period (for example, 300 seconds) after the input of power from the power line 4 to the power generating device 9 begins. The power generating device 9 stops supplying power to the power line 4 by operating, for example, in an idling state.

[0050] Specifically, when the switching panel 3 and the power conditioner 12 operate as described above, the delay timer circuit 3b does not supply power to the electromagnetic coil 3a, and power conditioner 12 stops inputting and outputting power (i.e., the period during which the first predetermined period (e.g., 2 seconds) and the second predetermined period (e.g., 300 seconds) overlap), no power is supplied to the power line 4. Therefore, if this period is equal to or longer than a third predetermined period (e.g., 1 second), the power generation device 9 determines that a power outage has occurred in the power line 4, and operates in a state in which the supply of power to the power line 4 is stopped (e.g., an idling state).

[0051] 5 is a diagram showing a state after the first predetermined period has elapsed after the power system 1 has shifted from the state shown in FIG. 2 to a state in which power has been restored. That is, the delay timer circuit 3b starts supplying power to the electromagnetic coil 3a in response to the lapse of the first predetermined period (for example, 2 seconds). Therefore, the changeover switch 3c switches to a state in which the contact a and the contact b are connected. Then, the power supplied from the power system 1 is supplied to the power line 4 via the changeover panel 3. In this way, the changeover panel 3 is configured to switch from the independent connection state to the grid connection state after the first predetermined period has elapsed when the power system 1 goes from an abnormal state in which the power system 1 does not normally supply power to the changeover panel 3 to a normal state in which the power system 1 normally supplies power.

[0052] Furthermore, the power generation device 9 can recognize that the supply of power to the power line 4 has been resumed. In this case, the power generation device 9 stops the supply of power to the power line 4 for a second predetermined period (300 seconds). In other words, when the input of power from the power line 4 to the power generation device 9 is stopped for a third predetermined period, the power generation device 9 stops the supply of power from the power generation device 9 to the power line 4 while the input of power from the power line 4 to the power generation device 9 is stopped and for a second predetermined period after the input of power from the power line 4 to the power generation device 9 has started. The state shown in FIG. 5 is a state in which the power conditioner 12 is in the middle of stopping the input and output of power for the second predetermined period (e.g., 300 seconds).

[0053] 6 is a diagram showing the state at the time when the power conditioner 12 has finished the state in which the input / output of power is stopped for the second predetermined period (300 seconds). In this case, the power conditioner 12 can input / output power between the switchboard 3 by operating the inverter 14, can input power from the solar cell device 18 by operating the DC / DC conversion unit 15, can input power between the charge / discharge device 19 by operating the DC / DC conversion unit 16, and can input power from the electric cable 21 by operating the input power conversion unit 17.

[0054] In the state shown in FIG. 6, the power generation device 9 is in the process of stopping the output of power to the power line 4 for a second predetermined period (300 seconds).

[0055] Thereafter, when the state in which the power generation device 9 stops inputting and outputting electric power for the second predetermined period (300 seconds) ends, the power generation device 9 goes into a state in which it supplies electric power to the power line 4, as shown in FIG.

[0056] As described with reference to FIG. 4 to FIG. 6, when the power system 1 goes from an abnormal state to a normal state, the switchboard 3 switches from the independent connection state to the grid connection state after a first predetermined period (e.g., 2 seconds) has elapsed, and the power conditioner 12 stops the input and output of power for a second predetermined period (e.g., 300 seconds). In other words, even if the power system 1 goes from an abnormal state to a normal state, the power line 4 is electrically connected to the power conditioner 12 and is not electrically connected to the power system 1 until the first predetermined period has elapsed, and the supply of power from the power conditioner 12 to the power line 4 is stopped for the second predetermined period. Therefore, the power generation device 9 detects that the input of power from the power line 4 to the power generation device 9 has stopped for a third predetermined period (e.g., 1 second). Then, the power generation device 9 stops the supply of power from the power generation device 9 to the power line 4 while the input of power from the power line 4 to the power generation device 9 has been stopped and for a second predetermined period after the input of power from the power line 4 to the power generation device 9 has started. In this way, when the power system 1 goes from an abnormal state to a normal state, the power conditioner 12 stops inputting and outputting power for the second predetermined period, and the power generation device 9 stops supplying power to the power line 4 for the second predetermined period from when the input of power from the power line 4 to the power generation device 9 begins. As a result, when the power system 1 goes from an abnormal state to a normal state, it is possible to reliably provide a period during which the power conditioner 12 and the power generation device 9 do not supply power to the power line 4.

[0057] <Second embodiment> The power supply system of the second embodiment differs from the above-mentioned embodiment in that a power supply switching unit is provided. The power supply system of the second embodiment will be described below, but the description of the same configuration as the above-mentioned embodiment will be omitted.

[0058] 7 and 8 are diagrams showing the configuration of a power supply system according to the second embodiment. As shown in the figure, the power supply system includes a power supply switch 23 connected to a power conditioner 12. The power supply switch 23 is connected to an electric cable 21, a connection line 27, and a relay line 28. In other words, the power supply switch 23 connects between the electric cable 21 and the connection line 27, connects between the electric cable 21 and the relay line 28, and connects between the connection line 27 and the relay line 28.

[0059] The connection line 27 is connected to a connection point P2 of the power line 4 via a breaker 11. The connection point P2 is located downstream (i.e., away from the power grid 1) of a connection point P1 of the power generation device 9 to the power line 4.

[0060] As shown in Figures 7 and 8, when the system side electric plug 20 is not connected to an electric outlet and therefore no power is supplied to the electric cable 21, the power supply switch 23 is configured to switch to a first connection state in which the power conditioner 12 and the connection line 27 are electrically connected and the power conditioner 12 and the electric cable 21 are not electrically connected.

[0061] Also, as shown in FIG. 9, when the system side electric plug 20 is connected to an electric outlet and electric power is supplied to the electric cable 21, the power supply switch 23 is configured to switch to a second connection state in which the power conditioner 12 and the electric cable 21 are electrically connected and the power conditioner 12 and the connection line 27 are not electrically connected.

[0062] Specifically, the electric cable 21 connects between the system-side electric plug 20 and the power supply switch 23. The connection line 27 connects between the breaker 11 connected to the connection point P2 of the power line 4 and the power supply switch 23. The two lines constituting the connection line 27 are connected to the first voltage line (U-phase) and the neutral line (N-phase) of the power line 4, respectively. The relay line 28 connects between the power conditioner 12 and the power supply switch 23.

[0063] The power supply switch 23 includes a changeover switch 25 and a changeover switch 26. Contacts a of the changeover switches 25 and 26 are connected to a relay line 28. Specifically, the contact a of the changeover switch 25 is connected to one of the two lines that constitute the relay line 28, and the contact a of the changeover switch 26 is connected to the other of the two lines that constitute the relay line 28.

[0064] Contacts b of the changeover switches 25 and 26 are connected to the connection line 27. Specifically, the contact b of the changeover switch 25 is connected to one of the two lines constituting the connection line 27 (U-phase), and the contact b of the changeover switch 26 is connected to the other of the two lines constituting the connection line 27 (N-phase).

[0065] The contacts c of the changeover switches 25 and 26 are connected to the electric cable 21. Specifically, the contact c of the changeover switch 25 is connected to one of the two lines that make up the electric cable 21, and the contact c of the changeover switch 26 is connected to the other of the two lines that make up the electric cable 21.

[0066] The power supply switch 23 includes an electromagnetic coil 24 electrically connected to the electric cable 21. When power is being supplied to the electric cable 21, i.e., when power is being supplied to the system-side electric plug 20, power is also supplied to the electromagnetic coil 24, which generates an electromagnetic force, and this electromagnetic force switches the changeover switches 25, 26 to a state in which the contacts a and c are connected. On the other hand, when power is not being supplied to the system-side electric plug 20, no electromagnetic force is generated in the electromagnetic coil 24, and the changeover switches 25, 26 switch to a state in which the contacts a and b are connected.

[0067] In this way, when power is supplied to the system side electric plug 20, the power supply switch 23 switches to a state in which the electric cable 21 and the power conditioner 12 are connected, and when power is not supplied to the system side electric plug 20, the power supply switch 23 switches to a state in which the connection line 27 and the power conditioner 12 are connected.

[0068] As described above, when the system side electric plug 20 is connected to an electric outlet and electric power is supplied to the electric cable 21, the power supply switch 23 switches to the second connection state in which the power conditioner 12 and the electric cable 21 are electrically connected. That is, the power conditioner 12 connected to the electric cable 21 connected to the system side electric plug 20 can receive electric power from the electric outlet. For example, the power conditioner 12 can receive electric power from a power supply device 22 such as a vehicle equipped with an electric outlet or a portable power generation device and power storage device equipped with an electric outlet. As a result, the charge / discharge device 19 connected to the power conditioner 12 can be charged with the electric power supplied from the electric outlet. In addition, when the system side electric plug 20 is not connected to an electric outlet and electric power is not supplied to the electric cable 21, the power supply switch 23 switches to the first connection state in which the power conditioner 12 and the connection line 27 connected to the power line 4 are electrically connected. That is, the charge / discharge device 19 connected to the power conditioner 12 can be charged with the power supplied from the power line 4 (for example, the power generated by the power generation device 9).

[0069] In this embodiment, the power conditioner 12 may also limit the current flowing through the electric cable 21 to a predetermined current or less that is smaller than the rated current of the breaker 11 (for example, a current of 30% of the rated current or less). By limiting in this manner, the current flowing through one breaker 11 to which the electric cable 21 is connected becomes a predetermined current or less that is sufficiently smaller than the rated current, and it is possible to prevent a large current from continuing to flow through the breaker 11. For example, if the rated current of the breaker 11 is 20 A and the power conditioner 12 is set to limit the current flowing through the electric cable 21 to 30% of the rated current of the breaker 11, the current flowing through the electric cable 21 will be 6 A (=20 A×0.3).

[0070] <Another embodiment> In the above embodiment, the configuration of the power supply system can be modified as appropriate. For example, as shown in Fig. 10, the connection line 27 may be configured with three wires, a first voltage wire (U phase), a second voltage wire (V phase), and a neutral wire (N phase). An electric outlet 29 may be provided to be connected to the three wires. The electric outlet 29 may be used to supply 200V power for charging the power supply device 22 of, for example, an electric vehicle.

[0071] In the above embodiment, specific numerical examples are given for the lengths of the first specified period, the second specified period, and the third specified period, but the numerical values ​​given in the above embodiment are given for illustrative purposes and can be changed as appropriate.

[0072] In the above embodiment, the input power conversion unit 17 of the power conditioner 12 may stop the operation of receiving the input of power (power input operation) when there is a voltage input from the interconnection line 5 to the power conditioner 12, and may perform the operation of receiving the input of power when there is no voltage input from the interconnection line 5 to the power conditioner 12 and there is a voltage input to the input power conversion unit 17.

[0073] In the above embodiment, the U phase of the single-phase three-wire power line 4 is the first voltage line and the V phase is the second voltage line, but conversely, the V phase may be the first voltage line and the U phase may be the second voltage line. Also, in the above embodiment, an example has been described in which the power generation device 9 and the system side electric outlet 8a connected to the electric cable 21 are both connected to the U phase and the N phase, but the power generation device 9 and the system side electric outlet 8a may both be connected to the V phase and the N phase.

[0074] 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, provided that no contradiction arises. Furthermore, the embodiments disclosed in this specification are illustrative, and the embodiments of the present invention are not limited thereto, and can be appropriately modified within the scope that does not deviate from the purpose of the present invention. [Industrial Applicability]

[0075] The present invention can be applied to a power supply system that can effectively utilize a device having a power supply function. [Explanation of symbols]

[0076] 1: Power system 3: Single phase 3: Switching board 3d: Breaker 4: Power lines 7: Power load 7a: Power load 7b: Power load 8: System side electrical outlet 8a: System side electrical outlet 8b: System side electrical outlet 9: Power generation equipment 11: Breaker 12: Power conditioner 13: Switch 19: Charge / discharge device 20: System side electrical plug 21: Electrical cable 23: Power switch 27: Connection line 29: Electrical outlet

Claims

1. A power supply system including a power generation device, a charge / discharge device, and a single-phase three-wire power line having a first voltage line, a second voltage line, and a neutral line, A power conditioner to which the charging / discharging device is connected; A switching panel that switches between an interconnected connection state in which the power line to which the power generation device and the power load are connected is electrically connected to both the power grid and the power conditioner, and an independent connection state in which the power line is electrically connected to the power conditioner and is not electrically connected to the power grid; a system-side electrical outlet connected to the first voltage line and the neutral line of the power line and not connected to the second voltage line; a system-side electric plug that is connected to an electric cable that is connected to the power conditioner and that is connectable to an electric outlet that can supply electric power; the power generation device is an AC 100V power supply connected to the first voltage line and the neutral line constituting the power line, and adjusts the power supply to the power line so that power is not supplied from the power line to the switching panel provided upstream of the power line; A power supply system configured to allow the system-side electrical plug to be connected to the system-side electrical outlet.

2. 2. The power supply system according to claim 1, wherein the length of the electrical cable is such that the system-side electrical plug can be connected to the system-side electrical outlet.

3. the system-side electrical outlet is connected to the power line via a breaker; The power supply system according to claim 1 or 2, wherein the power conditioner limits the current flowing through the electric cable to a predetermined current or less that is smaller than a rated current of the breaker.

4. A power supply system including a power generation device, a charge / discharge device, and a single-phase three-wire power line having a first voltage line, a second voltage line, and a neutral line, A power conditioner to which the charging / discharging device is connected; A switching panel that switches between an interconnected connection state in which the power line to which the power generation device and the power load are connected is electrically connected to both the power grid and the power conditioner, and an independent connection state in which the power line is electrically connected to the power conditioner and is not electrically connected to the power grid; A power supply switch connected to the power conditioner; a system-side electric plug connected to an electric cable connected to the power supply switch and connectable to an electric outlet capable of supplying electric power; a connection line connected to the first voltage line and the neutral line of the power line, the connection line connecting the power supply switch and the power line; the power generation device is an AC 100V power supply connected to the first voltage line and the neutral line constituting the power line, and adjusts the power supply to the power line so that power is not supplied from the power line to the switching panel provided upstream of the power line; The power supply system is configured so that, when the system side electric plug is not connected to the electric outlet and power is not supplied to the electric cable, the power supply switch switches to a first connection state in which the power conditioner is electrically connected to the connecting line and the power conditioner is not electrically connected to the electric cable, and, when the system side electric plug is connected to the electric outlet and power is supplied to the electric cable, the power supply switch switches to a second connection state in which the power conditioner is electrically connected to the electric cable and the power conditioner is not electrically connected to the connecting line.

5. the connection line is connected to the power line via a breaker, The power supply system according to claim 4 , wherein the power conditioner limits the current flowing through the power supply switch to a predetermined current or less that is smaller than a rated current of the breaker.

6. When the power grid goes from an abnormal state in which the power grid does not normally supply power to the switching board to a normal state in which the power grid normally supplies power, after a first predetermined period has elapsed, the switching board switches from the independent connection state to the grid connection state; When the power grid changes from the abnormal state to the normal state, the power conditioner stops inputting and outputting power for a second predetermined period that is equal to or longer than the first predetermined period; 5. The power supply system according to claim 1 or 4, wherein, when the input of power from the power line to the power generation device is stopped for a third predetermined period shorter than the first predetermined period, the power generation device stops supplying power from the power generation device to the power line while the input of power from the power line to the power generation device is stopped and for the second predetermined period after the input of power from the power line to the power generation device starts.

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