Power system

Abstract

This invention provides a power system that is safer than conventional systems. [Solution] The system comprises a distributed power supply unit, a first power receiving facility, a second power receiving facility, a connecting route, and a distributed route. The connecting route connects the first power receiving facility and the second power receiving facility and includes a first switchgear and a second switchgear. The distributed route connects the connecting route and the distributed power supply unit and is connected between the first switchgear and the second switchgear of the connecting route. The first switchgear and the second switchgear are regulated so that when one of the switchgears is closed, the other switchgear is always open. The system is configured to switch between a first connection state in which power can be supplied from the distributed power supply unit to the first power receiving facility via the first switchgear, and a second connection state in which power can be supplied from the distributed power supply unit to the second power receiving facility via the second switchgear.

Description

Technical Field

[0001] The present invention relates to a power system.

Background Art

[0002] Conventionally, there has been a power conversion system that supplies power from a common solar cell to a plurality of neighboring consumers (for example, Patent Document 1). The power conversion system of Patent Document 1 has branch wirings leading from the solar cell to each consumer, and system connection relays are interposed in these branch wirings, respectively. And, the power conversion system of Patent Document 1 can connect / open the branch wiring by opening / closing the system connection relay. For a consumer corresponding to the connection state of the connection relay, power is supplied from the solar cell to the load via the connection relay, and for a consumer corresponding to the open state of the connection relay, power supply from the solar cell to the load is cut off by the connection relay.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the power conversion system of Patent Document 1, since the loads of the consumers are electrically connected by the branch wirings connected to each consumer, if a problem occurs in the control device of each connection relay or temporary electrical noise or the like occurs, there is a possibility that the system connection relays may both be in the connected state. Generally, the amount of electric power used for the load varies for each consumer, so there are often voltage differences between the loads used by the consumers. In such a case, if the system connection relays are both in the connected state, there is a possibility that current may flow from the consumer with a higher voltage to the consumer with a lower voltage. Furthermore, each customer receives power from the grid, and in the event of an electrical accident in a customer's electrical equipment, the circuit breaker at the power receiving unit normally cuts off the current from the grid. However, if both grid connection relays are connected, even after an electrical accident occurs at one customer and the circuit breaker at the power receiving unit cuts off the current from the grid, there is a possibility that current from the grid power supply to the other customer's electrical equipment may continue to flow to the electrical equipment where the accident occurred, posing a safety problem.

[0005] Therefore, the objective of this invention is to provide a power system that is safer than conventional systems. [Means for solving the problem]

[0006] One aspect of the present invention for solving the above-mentioned problems is a power system comprising a distributed power supply unit, a first power receiving facility, a second power receiving facility, a connecting route, and a distributed route, wherein the connecting route connects the first power receiving facility and the second power receiving facility and includes a first switchgear and a second switchgear, the distributed route connects the connecting route and the distributed power supply unit and is connected between the first switchgear and the second switchgear of the connecting route, the first switchgear and the second switchgear are regulated so that when one of the switchgears is in a closed state, the other switchgear is always in an open state, and the power system is switchable between a first connection state in which power can be supplied from the distributed power supply to the first power receiving facility via the first switchgear and a second connection state in which power can be supplied from the distributed power supply to the second power receiving facility via the second switchgear.

[0007] According to this configuration, since either the first or second switchgear is kept open at all times, it is possible to prevent the first and second power receiving equipment from conducting electricity through the connecting path, and to prevent current from flowing from the higher-voltage power receiving equipment to the lower-voltage power receiving equipment. Therefore, it is safer than conventional methods.

[0008] A preferred configuration includes a switching device having the first switching device and the second switching device.

[0009] A preferred configuration is that the distributed power supply unit is capable of supplying AC power to the switching device.

[0010] A preferred configuration is that the connection path includes a cutoff unit that interrupts the flow of power through the connection path when a current greater than the maximum output current of the distributed power supply unit flows through it.

[0011] A preferred configuration is one in which the first switchgear has a first switch section, the second switchgear has a second switch section, and the first switch section and the second switch section are mechanically and electrically interlocked when switching between the first and second connection states.

[0012] A preferred configuration includes a schedule setting unit capable of setting a schedule for switching between the first connection state and the second connection state, and the first connection state and the second connection state are switched according to the schedule set by the schedule setting unit.

[0013] A preferred aspect is that the schedule includes the transition date and transition time.

[0014] A preferred configuration is that the first power receiving equipment and the second power receiving equipment are connected to the same or different power grids.

[0015] A preferred configuration includes a first base equipped with the distributed power supply unit, the first power receiving equipment, the first switchgear, and the second switchgear, and a second base equipped with the second power receiving equipment.

[0016] The aspects described above can be dependent on each other, refer to some of their components, or substitute for some of their components, as long as they fall within the technical scope of the present invention. [Effects of the Invention]

[0017] According to the power system of the present invention, it is possible to prevent the first power receiving facility and the second power receiving facility from being electrically connected through the connection side path, and the safety is higher than the conventional one.

Brief Description of the Drawings

[0018] [Figure 1] It is an explanatory diagram of the power system according to the first embodiment of the present invention, and is a diagram conceptually showing a first connection state in which the first switching device is in a closed state and the second switching device is in an open state. [Figure 2] It is an explanatory diagram of the power system of FIG. 1, and is a diagram conceptually showing a second connection state in which the first switching device is in an open state and the second switching device is in a closed state.

Modes for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described in detail.

[0020] As shown in FIG. 1, the power system 1 according to the first embodiment of the present invention is provided across a first consumer base 2 (first base) under the management of a first power consumer and a second consumer base 3 (second base) under the management of a second power consumer. The power system 1 is provided with a first electrical equipment 10, a switching device 11, a distributed power supply unit 12, and a control device 13 at the first consumer base 2, and a second electrical equipment 15 is provided at the second consumer base 3. Then, in the power system 1, the first electrical equipment 10 provided at the first consumer base 2 and the second electrical equipment 15 provided at the second consumer base 3 are connected via a switching device 11 connected to the distributed power supply unit 12, and the power generated by the common distributed power supply unit 12 is selectively supplied to the first electrical equipment 10 side and the second electrical equipment 15 side by the switching device 11.

[0021] <First consumer base 2> The first consumer base 2 is a base owned and managed by the first power consumer, and as described above, includes the first electrical equipment 10, the switching device 11, the distributed power supply unit 12, and the control device 13.

[0022] (Electrical equipment 10) As shown in Figure 1, the first electrical equipment 10 includes a first power receiving equipment 20 and a first power load 21 as its main components.

[0023] The first power receiving equipment 20 is connected to the commercial power grid 100a (grid power) and is equipped to receive power from the commercial power grid 100a and supply power to the first power load 21. The first power receiving equipment 20 is connected to the distributed power supply unit 12 via a switching device 11, and is equipment that receives power from the distributed power supply unit 12 via the switching device 11, enabling the supply of power to the first power load 21. The first power receiving equipment 20 is connected to the second power receiving equipment 60 via the connection route 33 of the switching device 11.

[0024] The first power load 21 is something that consumes electricity, and includes, for example, lighting loads such as lights, televisions, household air conditioners, personal computers, and hair dryers, as well as power loads such as elevators, machine tools, large refrigerators, and large air conditioners.

[0025] (Switching device 11) As shown in Figure 1, the switching device 11 includes a first switchgear 30, a second switchgear 31, a circuit breaker 32 (circuit breaker), a connection-side path 33, and a distribution-side path 34. The switching device 11 is capable of switching between a first connection state, in which the first switchgear 30 shown in Figure 1 is closed and the second switchgear 31 is open, thereby connecting the first power receiving equipment 20 and the distributed power supply unit 12, and a second connection state, in which the first switchgear 30 is open and the second switchgear 31 is closed, thereby connecting the second power receiving equipment 60 and the distributed power supply unit 12, as shown in Figure 2.

[0026] As shown in Figure 1, the first switchgear 30 has a first switch section 40 and a first electromagnet section 41, and is a magnetic switch that receives an electrical signal from the control device 13 to connect and disconnect the first power receiving equipment 20 and the distributed power supply section 12. The first switchgear 30 is located midway along the connection-side path 33 and between the first power receiving equipment 20 of the first electrical equipment 10 and the second power receiving equipment 60 of the second electrical equipment 15, and is positioned on the side of the first power receiving equipment 20 than the intersection 35 of the connection-side path 33 and the distribution-side path 34.

[0027] As shown in Figure 1, the second switchgear 31 has a second switch section 45 and a second electromagnet section 46, and is a magnetic switch that receives an electrical signal from the control device 13 to connect and disconnect the second power receiving equipment 60 and the distributed power supply unit 12. The second switchgear 31 is located midway along the connection-side path 33 and between the first power receiving equipment 20 of the first electrical equipment 10 and the second power receiving equipment 60 of the second electrical equipment 15, and is located on the side of the second power receiving equipment 60 beyond the intersection 35 of the connection-side path 33 and the distribution-side path 34.

[0028] The first opening / closing device 30 and the second opening / closing device 31 are connected by a connecting member 50, as shown in Figure 1, and are structured to interlock so that the states of their respective switch sections 40 and 45 are always different, one in the open state and the other in the closed state. In other words, the first switchgear 30 and the second switchgear 31 are designed so that when one switchgear is open, the other switchgear is closed, and they are multiple-layeredly controlled by both electrical and mechanical interlocking functions to prevent them from being closed simultaneously.

[0029] Specifically, the first switchgear 30 has an electrical interlocking function such that when the second switchgear 31 is closed, no electrical signal is input to the first electromagnet unit 41 by an electrical circuit (not shown), and the second switchgear 31 has a function such that when the first switchgear 30 is closed, no electrical signal is input to the second electromagnet unit 46.

[0030] Furthermore, as shown in Figure 1, the first opening / closing device 30 has a mechanical interlocking function. When the first electromagnet unit 41 receives an electrical signal from the control device 13, it presses one side of the connecting member 50. The pressing unit 51 provided on one side of the connecting member 50 mechanically presses the first switch unit 40 of the first opening / closing device 30, closing it or maintaining it in the closed state. Simultaneously, the connecting member 50 rotates around the pivot point F due to the pressing force from the first electromagnet unit 41, causing the pressing unit 52 provided on the other side of the connecting member 50 to move away from the second switch unit 45 of the second opening / closing device 31, opening it or maintaining it in the open state. On the other hand, as shown in Figure 2, when the second electromagnet unit 46 of the second opening / closing device 31 receives an electrical signal from the control device 13, it presses the other side of the connecting member 50, and the pressing part 52 provided on the other side of the connecting member 50 mechanically presses the second switch unit 45 of the second opening / closing device 31 to close it or maintain it in the closed state. At the same time, the connecting member 50 rotates around the pivot point F due to the pressing force from the second electromagnet unit 46, and the pressing part 51 provided on one side of the connecting member 50 moves away from the first switch unit 40 of the first opening / closing device 30 to open it or maintain it in the open state.

[0031] In this way, the first switchgear 30 and the second switchgear 31 are regulated so that when one switchgear is in a closed state, the other switchgear is always in a closed state.

[0032] The circuit breaker 32 is located in the middle of the connection path 33 and is installed between the first power receiving equipment 20 and the first switchgear 30 of the first electrical equipment 10. It is an overcurrent circuit breaker that interrupts the flow of power through the connection path 33 when a current larger than the maximum output current of the distributed power supply unit 12 flows through the connection path 33.

[0033] (Distributed power supply section 12) The distributed power supply unit 12 consists of power supply equipment such as solar power generation equipment, wind power generation equipment, hydroelectric power generation equipment, biomass power generation equipment, geothermal power generation equipment, fuel cells, and energy storage devices, and is the part that can supply power to each of the power receiving equipment 20,60. The distributed power supply unit 12 in this embodiment is a solar power generation system and includes a solar cell and a power converter that converts DC power to AC power. The DC power generated by the solar cell is converted to AC power by the power converter and can be supplied to the switching device 11.

[0034] (Control device 13) The control device 13 transmits electrical signals to the electromagnet sections 41 and 46 of the switchgears 30 and 31, thereby switching the connection state between the first switchgear 30 and the second switchgear 31. The control device 13 of this embodiment includes a schedule setting unit 70 that can set a schedule including the date and time of switching the connection status in at least the switching device 11. For example, the control device 13 sends an electrical signal to the switching device 11 based on a schedule set in advance by the schedule setting unit 70, and the switching device 11 is able to switch between the first connection state and the second connection state at predetermined intervals. The method of setting the schedule by the schedule setting unit 70 is not particularly limited, but for example, based on the actual power usage status by day of the week and season when power is used with power loads 21 and 61 at the first customer site 2 and the second customer site 3, it is possible to consider and set which of the first customer site 2 or the second customer site 3 to which the distributed power supply unit 12 should be connected to in order to make effective use of the distributed power supply unit 12. As in this embodiment, when the distributed power supply unit 12 is a solar power generation facility, the timing of switching between the first connection state and the second connection state by the switching device 11 during the night when power generation is not occurring can be set to reliably prevent the generation of arcs during the switching. As shown in Figure 1, the control device 13 can perform the above switching by directly connecting to the switching device 11 without connecting to a network. However, it may also be possible to connect to a network and rewrite the schedule via remote control. This would be more convenient for operation.

[0035] <Second Customer Base 3> The second customer base 3 is a base owned and managed by the first electricity customer, and is located in a different building or on a different site from the first customer base 2. The second customer base 3 is equipped with the second electrical equipment 15, as shown in Figure 1.

[0036] (Second Electrical Equipment 15) As shown in Figure 1, the second electrical equipment 15 includes a second power receiving equipment 60 and a second power load 61 as its main components.

[0037] The second power receiving equipment 60 is connected to the commercial power system 100b (system power) and is equipped to receive power from the commercial power system 100b and supply power to the second power load 61. Furthermore, the second power receiving equipment 60 is connected to the distributed power supply unit 12 via the switching device 11, and is equipment that receives power from the distributed power supply unit 12 via the switching device 11, enabling the supply of power to the second power load 61. The second power receiving equipment 60 is connected to the first power receiving equipment 20 via the connection route 33 of the switching device 11.

[0038] (Second power load 61) The second power load 61 is something that consumes electricity, and includes, for example, lighting loads such as lights, televisions, household air conditioners, personal computers, and hair dryers, as well as power loads such as elevators, machine tools, large refrigerators, and large air conditioners.

[0039] According to the power system 1 of this embodiment, the system includes a distributed power supply unit 12, a first power receiving facility 20, a second power receiving facility 60, a connecting route 33, and a distributed route 34. The connecting route 33 connects the first power receiving facility 20 and the second power receiving facility 60 and is equipped with a first switchgear 30 and a second switchgear 31. The distributed route 34 connects the connecting route 33 and the distributed power supply unit 12, and the first switchgear 30 and the second switchgear 31 of the connecting route 33... The first switchgear 30 and the second switchgear 31 are connected in between, and are regulated so that when one of the switchgears is closed, the other switchgear is always open. It is possible to switch between a first connection state in which power can be supplied from the distributed power supply unit 12 to the first power receiving equipment 20 via the first switchgear 30, and a second connection state in which power can be supplied from the distributed power supply unit 12 to the second power receiving equipment 60 via the second switchgear 31. In other words, according to the power system 1 of this embodiment, since the system is regulated so that either the first switchgear 30 or the second switchgear 31 is always in the open state, it is possible to prevent the first power receiving equipment 20 and the second power receiving equipment 60 from conducting through the connecting path 33, and to prevent current from flowing from the power receiving equipment with the higher voltage to the power receiving equipment with the lower voltage between the first power receiving equipment 20 and the second power receiving equipment 60. Therefore, it is safer than conventional systems. Furthermore, according to the power system 1 of this embodiment, since the first switchgear 30 and the second switchgear 31 are provided independently, even if an arc discharge occurs in one switchgear when the switching device 11 switches the connection state, it is possible to prevent the arc discharge from affecting the other switchgear, and to prevent the electrical equipment 10, 15 of multiple power consumers from being electrically connected due to the occurrence of the arc discharge.

[0040] In the power system 1 of this embodiment, it is preferable to include a switching device 11 having a first switchgear 30 and a second switchgear 31. With this configuration, since the switching device 11 is independent of the electrical equipment 10 and 15, maintenance and the like are easy.

[0041] In the power system 1 of this embodiment, it is preferable that the distributed power supply unit 12 is capable of supplying AC power to the switching device 11. The power system 1 of this embodiment is safe even with such a configuration.

[0042] In the power system 1 of this embodiment, it is preferable that the connection-side path 33 is equipped with a circuit breaker 32 that interrupts the flow of power through the connection-side path 33 when a current greater than the maximum output current of the distributed power supply unit 12 flows through it. With this configuration, even if the electrical equipment 10, 15 of each power consumer is connected due to a failure of the switchgear 30, 31 or the like, and an overcurrent flows, the circuit breaker 32 can safely interrupt the overcurrent.

[0043] In the power system 1 of this embodiment, the first switchgear 30 has a first switch section 40, and the second switchgear 31 has a second switch section 45. When switching between the first connection state and the second connection state, it is preferable to mechanically and electrically interlock the first switch section 40 and the second switch section 45. This makes it possible to more reliably prevent the electrical equipment 10,15 of multiple power consumers from being electrically connected.

[0044] In the power system 1 of this embodiment, it is preferable to have a control device 13 that can set a schedule for switching between a first connection state and a second connection state, and to switch between the first connection state and the second connection state according to the schedule set by the control device 13. By doing so, the configuration can be simplified and the frequency of switching can be reduced, thereby reducing the possibility of malfunctions, as the switching is performed according to a predetermined schedule, regardless of the measurement results of the power usage status of the power consumer.

[0045] In the power system 1 of this embodiment, the schedule preferably includes the switching date and switching time. This allows the switching timing of the switching device 11 to be precisely set.

[0046] In the power system 1 of this embodiment, it is preferable that the first power receiving equipment 20 and the second power receiving equipment 60 are connected to the same commercial power supply systems 100a and 100b. Even in such cases, it is possible to prevent electrical equipment 10 and 15 from conducting, so for example, if the voltage of the first electrical equipment 10 is higher than that of the second electrical equipment 15, it is possible to prevent reverse power flow from the first electrical equipment 10 through the second electrical equipment 15 to the commercial power supply system 100b.

[0047] In the power system 1 of this embodiment, there is a first customer base 2 equipped with a distributed power supply unit 12, a first power receiving equipment 20, a first switchgear 30, and a second switchgear 31, and a second customer base 3 equipped with a second power receiving equipment 60. Power can also be supplied from the distributed power supply unit 12 to the second customer base 3, which is managed by a different power consumer than the power consumer that manages the first customer base 2 where the distributed power supply unit 12 is installed.

[0048] In the embodiment described above, the first customer base 2 was equipped with a switching device 11, a distributed power supply unit 12, and a control device 13, but the present invention is not limited thereto. The second customer base 3 may be equipped with any or all of the switching device 11, the distributed power supply unit 12, and the control device 13.

[0049] In the embodiment described above, the first switchgear 30 and the second switchgear 31 were regulated in multiple ways by an electrical interlocking function and a mechanical interlocking function, but the present invention is not limited thereto. They may be regulated by either the electrical interlocking function or the mechanical interlocking function.

[0050] In the embodiments described above, the power receiving equipment 20 and 60 were connected to the same commercial power supply system 100a and 100b, but the present invention is not limited thereto. The power receiving equipment 20 and 60 may be connected to different commercial power supply systems 100a and 100b. Furthermore, the power receiving equipment 20 and 60 may be connected to power systems different from the commercial power systems 100a and 100b, respectively.

[0051] In the embodiment described above, a circuit breaker 32 was provided at the first customer base 2, but not at the second customer base 3. However, the present invention is not limited thereto. A circuit breaker 32 may also be provided at the second customer base 3. In this case, it is preferable that the circuit breaker 32 be provided between the second switchgear 31 and the second power receiving equipment 60.

[0052] In the embodiments described above, the components can be freely substituted or added between each embodiment, as long as they fall within the technical scope of the present invention. [Explanation of Symbols]

[0053] 1. Power Systems 2. First Customer Site (First Site) 3. Second Customer Base (Second Base) 11 Switching device 12 Distributed power supply section 13 Control device (schedule setting unit) 20. First Power Receiving Equipment 30 First Switching Device 31. Second Opening / Closing Device 32. Circuit breaker (circuit breaker) 33 Connecting Route 34 Distributed side paths 40. First switch section 45 Second switch section 60. Second power receiving equipment 70 Schedule Setting Section 100a,100b Commercial power system (grid power supply)

Claims

1. It has a distributed power supply unit, a first power receiving facility, a second power receiving facility, a connection side path, and a distributed side path. The aforementioned connection path connects the first power receiving equipment and the second power receiving equipment, and is equipped with a first switchgear and a second switchgear. The distributed-side path connects the connected-side path and the distributed-type power supply unit, and is connected between the first switchgear and the second switchgear of the connected-side path. The first and second opening / closing devices are regulated such that when one of the opening / closing devices is in a closed state, the other opening / closing device is always in an open state. A power system that can switch between a first connection state in which power can be supplied from the distributed power supply unit to the first power receiving equipment via the first switchgear, and a second connection state in which power can be supplied from the distributed power supply unit to the second power receiving equipment via the second switchgear.

2. The power system according to claim 1, comprising a switching device having the first switching device and the second switching device.

3. The power system according to claim 2, wherein the distributed power supply unit is capable of supplying AC power to the switching device.

4. The power system according to any one of claims 1 to 3, wherein the connection path is equipped with a shut-off unit that interrupts the flow of power through the connection path when a current greater than the maximum output current of the distributed power supply unit flows through it.

5. The first switching device has a first switch section, The second switching device has a second switch section, The power system according to any one of claims 1 to 3, wherein the first switch unit and the second switch unit are mechanically and electrically interlocked when switching between the first connection state and the second connection state.

6. It has a schedule setting unit that can set a schedule for switching between the first connection state and the second connection state, The power system according to any one of claims 1 to 3, which switches between the first connection state and the second connection state in accordance with a schedule set in the schedule setting unit.

7. The power system according to claim 6, wherein the schedule includes a switching date and a switching time.

8. The power system according to any one of claims 1 to 3, wherein the first power receiving equipment and the second power receiving equipment are connected to the same or different power grids.

9. The power system according to any one of claims 1 to 3, comprising a first base having the distributed power supply unit, the first power receiving equipment, the first switchgear, and the second switchgear, and a second base having the second power receiving equipment.

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