JP2015164384A - Dc power supply system, power source supply device, power supply control method in dc power supply system, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply DC power from a photovoltaic power generation device to a power supply path in an outage state in which DC power is not supplied from a DC power source device to the power supply path.SOLUTION: A DC power supply system 1 in which DC power is supplied from a DC power source device 20 for converting AC power supplied from a commercial power system 2 to the DC power, through a power supply path, to a load device comprises: a protective relay 13 (detection unit) for detecting a state in which DC power is not supplied from the DC power source device 20 to the power supply path; and a power source supply device 50 (control unit) for controlling supply of DC power to the power supply path on the basis of a result of the detection. The power supply path is constructed so that power generated by a photovoltaic power generation device 30 is converted to DC power by a PCS 40 and the DC power converted by the PCS 40 is supplied to the power supply path. The power source supply device 50 supplies DC power from the PCS 40 to the power supply path, after the protective relay 13 detects the state in which DC power is not supplied from the DC power source device 20 to the power supply path.

Description

  The present invention relates to a DC power supply system that supplies power to a load device connected to a DC voltage power supply path, a power supply device, a power supply control method in the DC power supply system, and a program.

  In recent years, in data centers, communication stations, and the like, construction of a DC power supply system that supplies DC power to various load devices such as routers and servers has been promoted. This DC power supply system converts a commercial AC power into a DC power having a predetermined voltage by a DC power supply device having an AC power system (commercial power system) as an input, and a plurality of loads via a power supply path (power supply line). Supply to the device.

  In the event that an abnormality such as a system fault occurs in the AC power system and DC power cannot be normally output from the DC power supply device to the load device, an engine generator is often provided as a backup. However, this engine generator contains carbon dioxide, sulfur oxide, nitrogen oxide, etc. in the exhaust gas. From the viewpoint of environmental protection, the power generator (such as a solar power generator using natural energy and a clean fuel cell of exhaust gas) The use of distributed power sources is desired. A distributed power supply usually operates in conjunction with a commercial power system. However, if the commercial power system fails, the distributed power supply is used to ensure maintenance and restoration work on the commercial power system side. It is stipulated that the operation is stopped and electrically disconnected from the commercial power system. For this reason, in order to use a distributed power source as a backup power source, when the commercial power system fails, it is necessary to stop the distributed power source, disconnect it from the commercial system, and start it up again. Has been done.

  By the way, a photovoltaic power generation apparatus is attracting attention as one of distributed power sources, and its introduction is progressing in various places. The solar power generation device is characterized in that clean power generation is possible as long as solar radiation is obtained without requiring fuel. Such a solar power generation device is used in combination with a power conditioner (Power Conditioning Subsystem) that converts electric power generated by itself. This power conditioner (sometimes simply referred to as “PCS” in the following description) boosts (or steps down) the output voltage of the photovoltaic power generator and supplies it to the power feeding path of the power feeding system. A control function is provided for controlling the output power in accordance with the amount of power generated by the power generation device or the like.

  A self-sustained operation support device is disclosed as one of the techniques for operating a power generation device and continuing power supply even when a commercial power system fails (see Patent Document 1). The self-sustained operation support device described in Patent Document 1 starts a fuel cell system used in conjunction with a system power supply, and supplies necessary power so that the fuel cell system operates independently.

  Further, as related literature, there is a “system interconnection technical requirement guideline for ensuring power quality” (see Non-Patent Literature 1).

JP 2008-022650 A

"System interconnection technical requirement guidelines for ensuring power quality", Agency for Natural Resources and Energy, [online], May 31, 2013, [Search on July 14, 2013] <http: //www.jhia.or .jp / pdf / keito_guideline.pdf>

By the way, the self-sustained operation support device described in Patent Document 1 described above is an AC power obtained by connecting DC power from a distributed power generator such as a fuel cell to a system power supply by a power conditioner when the system power supply is stopped. However, it does not disclose a method for supplying DC power to the power feeding path.
Further, the “system interconnection technical requirement guideline for ensuring power quality” described in Non-Patent Document 1 described above does not disclose a method for supplying DC power to a power feeding path.
As described above, neither Patent Document 1 nor Non-Patent Document 1 discloses a DC power supply system that uses an AC power system as a power source and supplies DC power converted from AC power to a power supply path. Also, there is no disclosure of a method for eliminating the power failure state of the power supply path.

  The present invention has been made in view of such circumstances, and in a power failure state in which direct current power is not supplied from the direct current power supply device to the power supply route, direct current power supply that can supply direct current power from the solar power generation device to the power supply route. A system, a power supply device, a power supply control method in a DC power supply system, and a program are provided.

  The present invention has been made to solve the above-described problems, and a direct current power supply system according to the present invention is provided with a direct current power supply device that converts alternating current power supplied from a commercial power system into direct current power. A DC power supply system that supplies DC power from a power supply device to a load device via a power supply path, the detection unit detecting a state in which the DC power is not supplied from the DC power supply device to the power supply path, and the detected result A controller that controls the supply of DC power to the power supply path based on the power conditioner converts the power generated by the photovoltaic power generation device into DC power, and the power conditioner converts the power The DC power is configured to be supplied in accordance with the control of the control unit, and the control unit supplies the DC power from the DC power supply device to the power supply path. There a state that is not supplied after detecting said detecting portion, and controls so as to supply the DC power from the power conditioner to the power supply path.

  Further, in the DC power supply system, the DC power supply system includes a blocking unit that blocks power supply from the power supply path toward the commercial power system so that a reverse power flow does not occur in the commercial power system, When the detection unit detects a state in which the DC power is not supplied from the DC power supply device to the power supply path, and the DC power is supplied from the power conditioner to the power supply path according to control by the control unit, the power supply The power supply from the route toward the commercial power system is blocked by the blocking unit.

  In the DC power supply system, the interruption unit is provided between a receiving point of the commercial power system and the DC power supply device.

  In the DC power supply system, the operation of the power conditioner that converts the power generated by the photovoltaic power generation apparatus and supplies the converted DC power to the power supply path is performed from the DC power supply apparatus. After the detection unit detects that the DC power is not supplied to the power supply path, the control unit temporarily stops the control unit, and after the control unit temporarily stops the operation of the power conditioner, the commercial power After detecting that the supply of power to the system is cut off and detecting that the supply of power is cut off, the power conditioner in a state where the operation has been stopped is restarted. The inverter is controlled to start up, and after the inverter is restarted, the inverter is turned off from the inverter. And wherein the DC power be supplied to the conductive paths.

  In the DC power supply system, the control unit temporarily stops the operation of the power conditioner when the detection unit detects that the DC power is not supplied to the power supply path from the DC power supply device. , After temporarily stopping the operation of the power conditioner, it is detected that an operation for instructing activation of the power conditioner is performed, and the power conditioner is turned on according to a detection result of the instructed operation. It is characterized by restarting.

  In the DC power supply system, the control unit detects a state in which the DC power is not supplied to the power supply path from the DC power supply device after detecting that an operation for instructing activation of the power conditioner has been performed. And when the power that can be output from the photovoltaic power generator is equal to or greater than a predetermined value, the power conditioner is restarted.

  Further, in the DC power supply system, when the power conditioner is started from a state where the operation is stopped, an operating voltage that enables power to be output from the power conditioner is supplied, and the power conditioner is A power supply device to be activated is provided.

  The DC power supply system may include the detection unit, the DC power supply device, a power supply device including the control unit, the solar power generation device, and the power conditioner.

  The power supply device of the present invention is provided with a DC power supply device that converts AC power supplied from a commercial power system into DC power, and supplies DC power from the DC power supply device to a load device via a power supply path. A power supply apparatus in a DC power supply system, comprising a control unit that controls supply of DC power to the power supply path, wherein the DC power supply system is in a state in which the DC power is not supplied from the DC power supply apparatus to the power supply path. A detection unit for detecting, and further, the power conditioner converts the electric power generated by the photovoltaic power generation device into DC power, and the DC power after the power conditioner converts depends on the control of the control unit The power supply path is configured so that the DC power is not supplied from the DC power supply device to the power supply path. After the part has been detected, and controls to supply the DC power from the power conditioner to the power supply path.

  The power supply control method of the present invention is provided with a DC power supply device that converts AC power supplied from a commercial power system into DC power, and supplies DC power from the DC power supply device to a load device via a power supply path. A power supply control method in a DC power supply system, in which a detection unit detects a state in which the DC power is not supplied from the DC power supply device to a power supply path, and a power conditioner generates DC power And the control unit controls to supply the DC power from the power conditioner to the power supply path after the detection unit detects that the DC power is not supplied from the DC power supply device to the power supply path. Including a procedure.

The program of the present invention is provided with a DC power supply device that converts AC power supplied from a commercial power system into DC power, and supplies DC power from the DC power supply device to a load device via a power feeding path. A detection unit that detects a state in which the DC power is not supplied from the DC power supply device to the power supply path, and further, from a power conditioner that converts the power generated by the photovoltaic power generation device, after the power conditioner has converted After the detection unit detects a state in which the DC power is not supplied from the DC power supply device to the computer of the DC power supply system in which the power supply path is configured so that DC power is supplied, the power conditioner A program for executing a step of controlling to supply the DC power from the power supply path .

  ADVANTAGE OF THE INVENTION According to this invention, DC power can be supplied to a feed path from a solar power generation device in the power failure state in which DC power is not supplied to a feed path from a DC power supply device.

It is a lineblock diagram showing a schematic structure of direct-current power feeding system 1 concerning a 1st embodiment of the present invention. It is a block diagram which shows the structure of a switch part. 2 is a configuration diagram illustrating a configuration example of a PCS 40 and a power supply device 50. FIG. It is explanatory drawing which shows the example of the switch control signal CNT. 4 is a flowchart showing a procedure of startup processing of the PCS 40 when a power failure occurs in the DC power supply system 1. 4 is an explanatory diagram illustrating an example of a control panel 53. FIG. It is a block diagram which shows the structural example of the control circuit of a switch part. 4 is a flowchart illustrating a procedure of power supply processing in the DC power supply system 1. 6 is an explanatory diagram illustrating an example of a startup screen of a PCS 40 on a control panel 53. FIG. It is a block diagram which shows schematic structure of 1 A of DC electric power feeding systems which concern on 2nd Embodiment of this invention. It is a flowchart which shows the procedure of the starting process of PCS40 at the time of the power failure of DC electric power feeding system 1A. It is a block diagram which shows schematic structure of DC power supply system 1B which concerns on 3rd Embodiment of this invention. It is a flowchart which shows the procedure of the starting process of PCS40 at the time of the power failure of DC power supply system 1B. It is a block diagram which shows schematic structure of DC power supply system 1C which concerns on 4th Embodiment of this invention. It is a flowchart which shows the procedure of the starting process of PCS40 at the time of the power failure of DC power supply system 1C. It is a flowchart which shows the 1st modification of the procedure of the starting process of PCS40. It is a flowchart which shows the 2nd modification of the procedure of the starting process of PCS40. It is a block diagram which shows schematic structure of AC electric power feeding system 1D.

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

(Overview)
In the DC power supply system according to the embodiment of the present invention, AC power supplied from a commercial power system is converted into DC power by a DC power supply device, and this DC power is supplied to a load device via a power supply path. The present invention relates to a DC power supply system in which a photovoltaic power generation apparatus supplies power to a power supply path via a power conditioner (PCS). Hereinafter, some embodiments of the present invention will be described. First, an outline thereof will be described.

  The DC power supply system 1 according to the first embodiment of the present invention shown in FIG. 1 is configured such that when the protective relay 13 detects that a power failure state has occurred in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20. The conditioner (PCS) 40 temporarily stops its operation. After that, when the power supply device 50 detects that the start button of the power conditioner 40 has been operated, the power supply device 50 is in a state in which no reverse power flow from the power supply path toward the commercial power system 2 occurs. After this detection, the power conditioner 40 is restarted, and DC power is supplied from the power conditioner 40 to the power feeding path.

In addition, the DC power feeding system 1A according to the second embodiment of the present invention shown in FIG. 10 has a power conditioner when the protective relay 13 detects that a power failure state in which power cannot be supplied from the commercial power system 2 has occurred. (PCS) 40 temporarily stops its operation. Thereafter, the power supply device 50A detects that no reverse power flow is generated from the power supply path toward the commercial power system 2, and after this detection, the power conditioner 40 is restarted to restart the power conditioner. Power is supplied from 40 to the power supply path.
That is, in the DC power supply system 1 of the first embodiment, the start button is operated as a condition for restarting the power conditioner 40 that is temporarily stopped due to the occurrence of a power failure in the commercial power system 2. In the DC power supply system 1A of the second embodiment, the power conditioner 40 is automatically restarted without requiring the start button to be operated.

Further, the DC power supply system 1B according to the third embodiment of the present invention shown in FIG. 12 is an example in which a power storage device 80 is connected to a power supply path via a power conditioner (PCS) 81 as a backup power supply device. . In this DC power supply system 1B, when the protective relay 13 detects that a power failure state in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20, the power conditioner (PCS) 40 of the solar power generation device 30 is detected. However, the operation is temporarily stopped and the supply of DC power from the power storage device 80 to the power supply path via the power conditioner 81 is started.
Thereafter, when the power supply device 50 detects that the start button of the power conditioner 40 has been operated, the power supply device 50 enters a state in which no reverse power flow occurs from the power supply path toward the commercial power system 2. After detecting this, the power conditioner 40 is restarted, and DC power is supplied from the power conditioner 40 to the power feeding path.
That is, in the DC power supply system 1B of the third embodiment, the start button is operated in the condition for restarting the power conditioner 40, as in the DC power supply system 1 of the first embodiment. However, the DC power supply system 1B is different from the configuration of the DC power supply system 1 in that the power storage device 80 is provided as a backup power supply device.

  Hereinafter, the DC power supply system 1 of the first embodiment, the DC power supply system 1A of the second embodiment, the DC power supply system 1B of the third embodiment, and other embodiments will be described in order.

[First Embodiment]
(Schematic configuration of DC power supply system 1)
FIG. 1 is a configuration diagram showing a schematic configuration of a DC power supply system 1 according to the first embodiment of the present invention. The DC power supply system 1 is an example of a DC power supply system installed in a building such as a data center or a communication station.

  1 includes a power receiving facility 10, a DC power supply (REC) 20, a power supply path to a load device, a switch unit 101, switch units 111 to 116, a solar power generation device 30, a power conditioner (PCS). 40) and a power supply device 50.

The power receiving facility 10 includes a circuit breaker (CB) 11, a transformer 12, and a protective relay 13. The protective relay 13 includes, for example, an overcurrent relay, a ground fault relay, an undervoltage relay (all not shown) and the like, and when these relays detect an abnormal state according to each detection condition, The signal is sent to the circuit breaker 11 to open the circuit breaker 11.
For example, the overcurrent relay opens the circuit breaker 11 when it detects that an overcurrent has flowed through the circuit, and the ground fault relay breaks the circuit breaker when it detects that a ground fault has occurred in the circuit or equipment. 11 is opened, and the undervoltage relay opens the circuit breaker 11 when it is detected that commercial power cannot be received from the commercial power system 2 due to a power failure or accident.
The circuit breaker 11 is provided with an auxiliary contact 11a mechanically interlocked with the main contact, and the open / closed state of the auxiliary contact 11a will be described later as a contact signal Aux indicating the open / closed state of the circuit breaker 11. It is output to the power supply device 50.

The transformer 12 steps down the high-voltage AC voltage (for example, three-phase AC 6600 V) supplied from the commercial power system 2 to a predetermined low-voltage AC voltage (for example, three-phase AC 400 V), and supplies this low-voltage AC voltage to the DC power supply device 20. Supply. The DC power supply device 20 is a rectifier that converts commercial AC power into DC power, and converts the low-voltage AC voltage input from the transformer 12 into a DC voltage having a predetermined voltage. The DC power supply device 20 includes an AC / DC converter 21 (FIG. 3). The AC / DC converter 21 converts an AC 400V AC voltage input from the transformer 12 into, for example, a DC 380V DC voltage. A DC voltage of 380 V is output to power supply paths P11 and N11 which are main power supply lines.
Note that the DC power supply device 20 includes an output current limiting function for limiting the output current so as not to exceed the rated current, a momentary excessive current (for example, a rated current of the rated current) due to a short circuit between the power supply paths P11 and N11. When a current of 300% flows, a protection function is provided to detect this excessive current and shut off the output.

A solar power generation device 30 is connected to the power feeding paths P11 and N11 via a power conditioner (PCS) 40 and a switch unit 101. The switch unit 101 includes a switch for connecting / opening between the PCS 40 of the solar power generation device 30 and the power feeding paths P11 and N11. When the switch unit 101 is in the connected state, the PCS 40 is connected to the DC power supply device 20. Enables linkage to the output of.
Moreover, the switch part 111 to the switch part 116 includes a switch for opening and closing the electric circuit in the power supply paths P28 and N28 from the power supply paths P21 and N21. Further, the power supply paths P11 and P21 to the power supply path P28 indicate positive-side power supply lines, and the power supply paths N11 and N21 to the power supply path N28 indicate negative-electrode-side power supply lines.
In the following description, the switch unit 101 and the switch units 111 to 116 are collectively referred to as “switch unit 100”.

  The power feeding paths P11 and N11 are connected to the input side of a distribution board (PDF) 61, and the DC power supply 20 is connected to the power feeding paths P21 and N21 via the distribution board 61 from the power feeding paths P28 and N28. Electric power is supplied from each load device L11 arranged in the system to the load device L16. Each of the load devices L11 to L16 is a device that operates with DC power supplied from the DC power supply device 20. For example, the load devices L11 to L16 are DC appliances, LED lighting, information devices such as personal computers and servers, and the like. In addition, a switch unit 116 to a switch unit 116 for setting a power supply range for supplying power from the load device L11 to the load device L16 are arranged at predetermined positions in the power supply routes P21 and N21 to the power supply routes P28 and N28. Yes. In other words, the switch unit 111 to the switch unit 116 are arranged in the power supply path at locations where the power supply range for supplying power from the solar power generation device 30 and the non-power supply range for not supplying power are divided.

  The power supply path will be described in more detail. The power supply paths P11 and N11 are connected to the input side of the distribution board (PDF) 61, and an overcurrent breaker (not shown) in the distribution board 61 is used. The branch circuit branches into power supply paths P21 and N21 and power supply paths P24 and N24. The power feeding paths P21 and N21 are connected to the power feeding paths P22 and N22 via the switch unit 111, and the load device L11 is connected to the power feeding paths P22 and N22. Further, the power feeding paths P23 and N23 are branched from the power feeding paths P22 and N22 via the switch unit 112, and the load device L12 is connected to the power feeding paths P23 and N23.

  On the other hand, the power feeding paths P24 and N24 branched from the distribution board 61 are branched to the power feeding paths P25 and N25 via the switch unit 113, and the load device L13 is connected to the power feeding paths P25 and N25. The power feeding paths P24 and N24 are branched to the power feeding paths P26 and N26 via the switch unit 114, and the load device L14 is connected to the power feeding paths P26 and N26. The power feeding paths P26 and N26 are branched to the power feeding paths P27 and N27 via the switch unit 115, and the load device L15 is connected to the power feeding paths P27 and N27. The power feeding paths P26 and N26 are branched to the power feeding paths P28 and N28 via the switch unit 116, and the load device L16 is connected to the power feeding paths P28 and N28.

  FIG. 2 is a configuration diagram illustrating the configuration of the switch unit. The switch unit 100 uses a double-throw contact (two contacts) like the switch SW shown in FIG. 2A to connect or open each of the positive-side feed line P and the negative-side feed line N. It is configured. Note that the switch unit 100 connects or connects only the positive-side power supply line P (or the negative-electrode side power supply line N) using a single throw contact (one contact), like the switch SW shown in FIG. You may make it open. Further, as shown in FIG. 2C, the switch unit 100 includes a first direction switch SWa, a second direction switch SWb, and a contact point of the third direction switch SWc, which are connected to each other in any of the three directions. It may be a T-type switch that can output a voltage input from the other direction in the other two directions or one direction.

  1 and 2 show an example of a switch using a mechanical contact as the switch unit 100. In practice, the switch SW is a semiconductor switching element such as an IGBT (Insulated Gate Bipolar Transistor). The semiconductor switch used is configured. This semiconductor switch is configured to connect and shut off the power supply path, supply DC current to the power supply path and load device of the supply destination when connected, and have the ability to cut off the load current flowing to the load device when cut off Has been. The configuration of the switch unit 100 will be described later.

  Returning to FIG. 1, the solar power generation device (PV) 30 includes a solar cell array (solar cell) 31. The solar cell array 31 converts solar energy into electricity and outputs the electricity to the PCS 40. The PCS 40 supplies the power generated by the solar power generation device 30 to the power supply paths P11 and N11 and supplies the power generated by the solar power generation apparatus 30 to the power supply paths P11 and N11 at the normal time when the DC power supply 20 supplies DC power. Reduce the amount of power used.

The switch unit 101 connected to the PCS 40 is opened when the protective relay 13 or the DC power supply device 20 detects that a failure (for example, a short circuit between lines) has occurred in the power supply paths P11 and N11. OFF) state, and the photovoltaic power generator 30 is separated from the grid.
In addition, when the PCS 40 of the solar power generation device 30 has a protection function that detects that a failure has occurred in the power supply paths P11 and N11 and interrupts the output current, for example, an overcurrent has flowed through the PCS 40. In the case where the function of detecting this fact and cutting off the output current is provided, the switch unit 101 can be omitted.

The power supply device 50 controls the operation of the PCS 40. This power supply device 50 cannot supply power from the commercial power system 2 to the DC power supply device 20, so that the output of the DC power supply device 20 is stopped and the power supply device 50 is in a power failure state (hereinafter referred to as “DC power supply device 20 power failure”). The operation of the PCS 40 is temporarily stopped. For example, the power supply device 50 detects that the circuit breaker 11 has been opened based on the contact signal Aux of the auxiliary contact 11a of the circuit breaker 11 input from the power receiving facility 10, and temporarily stops the operation of the PCS 40.
At the same time, the power supply apparatus 50 once opens the switch unit 116 from the switch unit 101 and the switch unit 111.
In addition, as a method of detecting a power failure state in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20, for example, the power supply device 50 has a voltage supplied to the power supply paths P11 and N11 below a predetermined voltage value ( For example, it may be detected that a power failure has occurred in the commercial power system 2 by detecting that the voltage has dropped to a value close to zero voltage).

Then, the power supply device 50 maintains the operation stop state of the PCS 40 until the start button 55 (FIG. 3) instructing the start of the PCS 40 is operated. When the power supply device 50 detects that the start button 55 for instructing the start of the PCS 40 is operated, the power supply device 50 detects that the circuit breaker 11 is in an open state by the contact signal Aux. That is, the power supply device 50 confirms that no reverse power flow is generated from the power supply path toward the commercial power system 2, and restarts the PCS 40 after this confirmation.
When the PCS 40 is restarted, as described later, the starting condition is that the power that can be output from the solar power generation device 30 is equal to or higher than a predetermined value. The electric power that is equal to or greater than the predetermined value can be set to an arbitrary value, for example, with the electric energy that can supply electric power to at least one load device as a lower limit value.

  Further, when the power supply device 50 restarts the PCS 40, it becomes impossible to supply a DC voltage to the power supply paths P11 and N11 due to a power failure of the DC power supply device 20, and the voltage on the secondary side (output side) of the PCS 40 is reduced. When it is detected that the voltage has fallen below a predetermined threshold voltage set in advance, the PCS 40 is supplied with an operating voltage serving as a reference for starting the PCS 40, and the PCS 40 is started independently.

That is, when the PCS 40 is connected to the power supply path of the DC power supply device 20 and the output of the PCS 40 is connected to the output of the DC power supply device 20, the PCS 40 detects the voltage of the power supply path. Therefore, when power is not supplied to the power supply path due to a power failure of the commercial power system 2 that hits the power supply of the DC power supply apparatus 20 or a failure of the DC power supply apparatus 20, the PCS 40 is necessary for itself to operate as the voltage of the power supply path. It is impossible to detect a voltage within a predetermined voltage range. Therefore, the power supply device 50 supplies the operating voltage serving as a reference to be output from the PCS 40 to the PCS 40 in the stopped state in which the output is stopped, so that the PCS 40 is activated independently.
The state in which power is not supplied from the DC power supply device 20 to the power supply paths P11 and N11 is when the commercial power system 2 fails, when the DC power supply device 20 breaks down, or when an accident occurs in the power supply paths P11 and N11. Occurs when the output of the DC power supply device 20 is interrupted by the above.

In addition, after the PCS 40 is activated, the power supply device 50 transmits a switch control signal CNT to the switch unit 100 that is once opened to control the open / close state of the switch unit 100. Thereby, the power supply device 50 supplies power from the solar power generation device 30 to the power feeding paths P11 and N11, and controls the power feeding ranges in the power feeding paths P28 and N28 from the power feeding paths P21 and N21.
That is, the power supply device 50 adjusts the power supply range from the power supply paths P21 and N21 to the power supply paths P28 and N28 by controlling the open / close state of the switch section 116 from the switch section 111. As a result, the power supply device 50 does not supply power to a load device used during a power failure (for example, a lighting device) that supplies power from the solar power generation device 30 when power cannot be supplied from the DC power supply device 20. A load device (for example, an air conditioner) can be set.

  In this way, the power supply device 50 supplies the operating voltage to the PCS 40 when the PCS 40 is in a stopped state and the operating voltage enabling the power output from the PCS 40 is not supplied from the DC power supply device 20 to the PCS 40. Then, the PCS 40 is activated independently. Furthermore, the power supply device 50 transmits a switch control signal to the switch unit 100, and controls the open / closed state of the switch unit 100 by the switch control signal. Thereby, the power supply device 50 sets a power supply range in the power supply path.

(Configuration of PCS 40 and power supply device 50 of solar power generation device 30)
FIG. 3 is a configuration diagram illustrating a configuration example of the PCS 40 and the power supply device 50 of the solar power generation device 30. As shown in FIG. 3, the PCS 40 includes a power generation amount control unit 41, a grid interconnection control unit 42, and a DC / DC converter 43.

In order to extract the maximum power from the solar power generation device 30, the power generation amount control unit 41 has an operating point (maximum) that maximizes the output of the solar cell array 31 in the IV (current-voltage) characteristics of the solar cell array 31. Power point). The maximum power point of the solar cell array 31 is shifted depending on the voltage actually required by the connected load. Since the IV characteristic changes depending on the solar radiation intensity, the module temperature, the state, etc., in order to obtain the maximum power, the optimum voltage or current must be automatically followed. Therefore, the power generation amount control unit 41 controls the solar cell array 31 to operate at the maximum power point.
In addition, the power generation amount control unit 41 notifies the power supply device 50 that the power that can be output from the solar power generation device 30 is “information on whether or not the power is greater than or equal to a predetermined value”. This “information on whether or not the power that can be output from the solar power generation device 30 is equal to or higher than a predetermined value” is used as a start condition when the power supply device 50 restarts the PCS 40 that has once stopped operating. It is done.

  Further, the grid interconnection control unit 42 detects the voltages of the power feeding paths P11 and N11 serving as power feeding buses, and adjusts the output voltage of the DC / DC converter 43 based on the detection result. For example, the grid interconnection control unit 42 detects the voltages of the power supply paths P11 and N11 in a normal state where a DC voltage is output from the DC power supply device 20 to the power supply paths P11 and N11, and based on the detection result. By adjusting the output voltage of the DC / DC converter 43, control is performed so that the power output from the PCS 40 can be fed to the power feeding paths P12 and N12. The DC / DC converter 43 is a step-up converter for stepping up the output voltage of the solar power generation device 30 and supplying power to the power supply paths P11 and N11.

The power supply device 50 includes a PCS activation unit 51, a bus voltage detection unit 51A, a switch control unit 52, a control panel 53, a storage battery 54, and an activation button 55.
The bus voltage detector 51A detects the DC voltage of the power supply paths P11 and N11 that are power supply buses. The bus voltage detection unit 51A, for example, is that power is not supplied from the DC power supply device 20 to the power supply paths P11 and N11 serving as power supply buses, and the voltage of the power supply paths P11 and N11 has decreased from a predetermined voltage value determined in advance. And the PCS activation unit 51 is notified of the detection result.

The PCS activation unit 51 uses a built-in storage battery 54 to generate a photovoltaic power generation device when power is not supplied from the DC power supply device 20 to the power supply paths P11 and N11 and an operating voltage serving as a reference for the output voltage is not supplied to the PCS 40. The operating voltage is supplied to the 30 PCSs 40 to start up the PCSs 40 independently.
The PCS activation unit 51 outputs an output from the photovoltaic power generator 30 that the circuit breaker 11 is opened when the activation button 55 is operated and the activation signal ST is input after the operation of the PCS 40 is temporarily stopped. After detecting that the available power is equal to or greater than a predetermined value, the PCS 40 is activated. Note that the activation button 55 may be arranged as an activation button 55A on the control panel 53 as shown in FIG. 9 described later.
Further, the PCS activation unit 51 controls the activation operation and the stop operation of the PCS 40, and also controls the activation operation and the stop operation of the PCS 81 (FIG. 12) of the power storage device 80 described later.

The switch control unit 52 controls the open / close state of the switch unit 100 in accordance with control from the control panel 53. The switch control unit 52 transmits the switch control signal CNT to the switch unit 101 and closes the switch unit 101 (on state), thereby connecting the photovoltaic power generation apparatus 30 to the power feeding paths P11 and N11.
Further, the switch control unit 52 transmits a switch control signal CNT from the switch unit 111 to the switch unit 116, and controls the open / close state of the switch unit 116 from the switch unit 111.
That is, the switch control unit 52 controls the power supply range in the power supply paths P28 and N21 from the power supply paths P21 and N21 by controlling the open / close state of the switch section 116 from the switch section 111.
For example, at the time of a power failure of the DC power supply device 20, the switch control unit 52 selects a lighting device or the like as a load device used during a power failure to supply power by the solar power generation device 30 and supplies power to the power supply path P <b> 21. And N21, the power supply range in the power supply paths P28 and N28 is set.

  FIG. 4 is an explanatory diagram illustrating an example of the switch control signal CNT. In the example of the switch control signal CNT shown in FIG. 4, the switch control signal CNT includes “switch identification information” and “on / off (open / close) information” of the switch. By transmitting the switch control signal CNT toward the switch unit 100, the switch unit 100 corresponding to the “switch identification information” turns on / off the switch based on the “on / off (open / close) information”. Open / close operation.

  Returning to FIG. 3, a dedicated signal line may be provided as a signal path for transmitting the switch control signal CNT to the switch unit 100, and at least one of the power supply paths P11 and N11, P21 and N21 to P28 and N28. You may make it utilize the electric power feeding path | route of a part as a signal wire | line. When a dedicated signal line is provided, the power for operating the switch unit 100 can also be supplied from the power supply device 50 via this signal line.

  In addition, the storage battery 54 in the power supply device 50 is always charged from, for example, power supply paths P11 and N11 in a normal state in which power is supplied from the DC power supply apparatus 20 to the power supply path. When the PCS 40 is activated at the time of a power failure of the DC power supply device 20, the storage battery 54 supplies the power supply device 50 with an operating voltage that causes the power supply device 50 to output power to the PCS 40. The operation of the device 50 is started, and an operating voltage is supplied from the power supply device 50 to the PCS 40 to start the PCS 40 independently. Instead of the storage battery 54, the PCS 40 may be activated independently using a fuel cell or an engine generator.

(Procedure for starting the PCS 40 at the time of a power failure in the DC power supply system 1)
FIG. 5 is a flowchart showing the procedure of the startup process of the PCS 40 at the time of a power failure of the DC power supply system 1.
Hereinafter, with reference to the flowchart shown in FIG. 5, the procedure of the startup process of the PCS 40 in the DC power supply system 1 will be described.
First, it is assumed that a power failure state has occurred in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20 (step S110).
When a power failure occurs in the commercial power system 2, the circuit breaker 11 in the power receiving facility 10 is opened by the operation of the undervoltage relay, and the auxiliary contact 11a of the circuit breaker 11 is opened. The power supply device 50 detects that the auxiliary contact 11a of the circuit breaker 11 has been opened based on the contact signal Aux, and detects that a power failure has occurred in the commercial power system 2.

Subsequently, the power supply device 50 temporarily stops the operation of the PCS 40 (step S115) and opens the switch unit 101 (step S120). Thereby, the power supply device 50 can once stop the operation of the PCS 40 when detecting that a power failure state has occurred in the commercial power system 2.
As a method for detecting the occurrence of a power failure in the commercial power system 2 and temporarily stopping the operation of the PCS 40, the bus voltage detection unit 51A of the power supply device 50 uses a predetermined voltage for the power supply paths P11 and N11. It is also possible to temporarily stop the operation of the PCS 40 by detecting that the voltage has decreased to a voltage value less than (for example, a value close to zero voltage). Alternatively, the PCS 40 itself may detect that the voltage of the power feeding paths P11 and N11 has decreased, and the PCS 40 may stop the operation by itself.

Subsequently, the power supply device 50 determines whether or not the activation button 55 that activates the PCS 40 has been operated (step S125).
And when it determines with the starting button 55 having been operated in the process of step S125 (step S125: Yes), the power supply apparatus 50 transfers to the process step of step S130, and can output from the solar power generation device 30. It is determined whether or not the power is greater than or equal to a predetermined value (step S130). That is, it is determined whether the solar power generation device 30 is in a state where it can obtain a sunshine amount equal to or greater than a predetermined value and can supply power greater than the predetermined value from the PCS 40 to the power supply path.

Subsequently, in the process of step S130, when it is determined that the photovoltaic power generation apparatus 30 is in a state in which power greater than or equal to a predetermined value can be output to the power supply path (step S130: Yes), the power supply apparatus 50 performs the process of step S135. It transfers to a process step and it is determined whether the circuit breaker 11 exists in the open state (step S135). For example, the power supply device 50 determines whether or not the circuit breaker 11 is in an open state based on the contact signal Aux.
In the power failure detection process in step S110, the power supply device 50 has already detected that the circuit breaker 11 has been opened based on the contact signal Aux. Therefore, in the determination process in step S135, the circuit breaker 11 is opened. This is done to reconfirm that it is in progress and can be omitted.

And when it determines with the circuit breaker 11 being in the open state in the process of step S135 (step S135: Yes), the power supply apparatus 50 starts PCS40 by the PCS starting part 51 (step S140). .
Subsequently, the power supply device 50 causes the switch control unit 52 to turn on the switch unit 101 to output DC power from the PCS 40 to the power feeding paths P11 and N11 (step S145). Then, after executing the process of step S145, the power supply device 50 ends the startup process of the PCS 40.

On the other hand, if it is determined in step S125 that the start button 55 has not been operated (step S125: No), the power supply device 50 returns to the process step of step S115, and the operation stop state of the PCS 40 and the switch unit 101 is kept open.
Moreover, in the process of step S130, when it determines with the solar power generation device 30 not being in the state which can output the electric power more than a predetermined value to an electric power feeding path (step S130: No), the power supply apparatus 50 will process step S115. Returning to the step, the operation stop state of the PCS 40 and the open state of the switch unit 101 are continued.
When it is determined in step S135 that the circuit breaker 11 is not opened (step S135: No), the power supply device 50 returns to the processing step of step S115, and the operation stop state of the PCS 40 and the switch unit 101 is kept open.

  Thereby, in the DC power supply system 1, when the protective relay 13 detects that a power failure state in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20, the PCS 40 temporarily stops its operation. Thereafter, when the power supply device 50 detects that the start button of the PCS 40 has been operated, the power supply device 50 is in a state where no reverse power flow from the power supply path toward the commercial power system 2 occurs. It can be detected and the PCS 40 can be restarted.

In addition, after starting the PCS 40 in step S140, when the switch unit 101 is turned on in step S145, if there is a possibility that a transient excessive current flows from the PCS 40 toward the power supply paths P11 and N11, The switch unit 101 may be turned on, and then the output voltage of the PCS 40 may be raised. For example, after the switch unit 101 is turned on, the output voltage of the PCS 40 may be gradually raised to prevent a transient excessive current from flowing.
Furthermore, when the DC power supply device 20 is in a power failure, the switch unit 101 is closed without being opened, thereby performing the opening process of the switch unit 101 in step S120 and the turning-on process of the switch unit 101 in step S145. Can be omitted (the same applies to FIGS. 11, 13, 15, 16, and 17 described later).

(Description of control panel 53)
Next, the control panel 53 will be described. The control panel 53 detects an operation for setting the open / close state (on / off state) of the switch unit 100, controls the switch control unit 52 according to the detected operation, and displays the open / close state of the switch unit 100. . The control panel 53 can be configured to include, for example, a touch panel display device.

  FIG. 6 is an explanatory diagram showing an example of the control panel 53. In the example shown in FIG. 6, a “single-line diagram display screen 53 a of the DC power supply system 1”, a “switch selection button 53 b” indicating a position for detecting an operation, and a “push-in button 53 c” ”And“ open button 53d ”are shown.

  In addition, in the “display screen 53a of the single-line connection diagram of the DC power supply system 1” shown in FIG. 6, all the load devices L11 to L16 in the DC power supply system 1 are displayed. You may make it select and display only the load apparatus which needs to supply electric power from the solar power generation device 30 at the time of the power failure of the power supply device 20. FIG.

For example, on the display screen 53a of this single-line diagram, the state of the switch unit 100 is indicated by the color of the area surrounding the switch unit with a broken line. For example, “green” is displayed when the switch unit 100 is in the open state, and “red” is displayed when the switch unit 100 is in the closed state.
When the switch unit 111 in the open state indicated by “SW111” is turned on, the user (more precisely, the administrator of the DC power supply system 1) operates the switch selection button 53b, and then displays a single-line connection diagram display screen. The area surrounded by the broken line of the switch unit 111 is operated on 53a. By operating the area indicating the switch unit 111, the control panel 53 starts blinking display of the area indicating the switch unit 111. By operating the input button 53c while the area indicating the switch unit 111 is blinking, the control panel 53 switches on the switch unit 111 via the switch control unit 52 in accordance with the above series of operations. To close. Further, the control panel 53 changes the display color of the switch unit 111 from “green” to “red”.

  Further, when the switch unit 111 in the closed state is opened, the switch selection button 53b is operated, and thereafter, the region surrounded by the broken line of the switch unit 111 is operated on the display screen 53a of the single-line connection diagram. By operating the area indicating the switch unit 111, the control panel 53 starts blinking display of the switch unit 111. By operating the release button 53d while the area indicating the switch unit 111 is blinking, the control panel 53 opens the switch unit 111 via the switch control unit 52 in accordance with the series of operations described above. Let Further, the control panel 53 changes the display color of the switch unit 111 from “red” to “green”. The same applies to other switch units 100.

  When the switch unit 100 is specified by operating the switch selection button 53b, a plurality of switch units 100 can be specified at the same time, such as simultaneously specifying the switch unit 111 and the switch unit 112.

(Configuration of control circuit of switch part)
FIG. 7 is a configuration diagram illustrating a configuration example of the control circuit of the switch unit. As shown in FIG. 7, the switch unit 100 is provided with a switch control signal receiving unit 71, a switch opening / closing unit 72, an opening / closing result notifying unit 73, a switch 74, and a power supply unit 75.

The switch control signal receiving unit 71 receives the switch control signal CNT from the switch control unit 52 in the power supply device 50.
Based on the switch control signal CNT received by the switch control signal receiving unit 71, the switch opening / closing unit 72 determines whether or not the switch opening / closing unit 72 is a switch designated by “switch identification information”. When the switch opening / closing unit 72 determines that the switch is the switch designated by the “switch identification information”, the switch opening / closing unit 72 turns on / off the switch 74 based on the “switch on / off information”. ) That is, the switch opening / closing unit 72 performs an opening / closing operation of the switch 74.

  When the switch opening / closing unit 72 turns on / off the switch 74, the opening / closing result notifying unit 73 transmits information on the operation result of turning on / off the switch 74 to the switch control unit 52 of the power supply device 50. The switch control unit 52 that has received the operation result information displays the open / close state of the switch 74 on the control panel 53 based on the on / off operation result information of the switch 74 received from the open / close result notification unit 73. Let

The power supply unit 75 supplies power to each of the switch control signal receiving unit 71, the switch opening / closing unit 72, and the opening / closing result notification unit 73. The power supply unit 75 may store electric power that causes the switch control signal receiving unit 71, the switch opening / closing unit 72, and the opening / closing result notification unit 73 to function.
As a result, the user can instruct opening / closing of the switch 74 on the power supply path by the control panel 53 and can also display and confirm the opening / closing result on the control panel 53.

Next, power supply processing in the DC power supply system will be described with reference to FIG.
FIG. 8 is a flowchart illustrating a procedure of power supply processing in the DC power supply system. In FIG. 8, after the DC power supply device 20 is in a power failure state, the PCS 40 is activated, and power is supplied from the solar power generation device 30 to the power supply paths P11 and N11 via the PCS 40. Indicates processing. In addition, when the DC power supply 20 is in a power failure state, the switch unit 111 to the switch unit 116 are temporarily opened.

  First, the control panel 53 detects a user instruction, and detects that there is a load device that requires power supply in accordance with the detected instruction (step S200).

Subsequently, the control panel 53 detects a user operation for designating a power supply range (step S210). For example, the control panel 53 detects that the switch unit 111 and the switch unit 112 are designated.
Subsequently, the control panel 53 controls the switch control unit 52 to sequentially turn on the switch unit 100 (more precisely, the switch 74 in the switch unit 100) corresponding to the detected operation (step S220). For example, the switch control unit 52 sequentially transmits a switch control signal CNT to the switch unit 111 and the switch unit 112 so that the switch unit 111 and the switch unit 112 are sequentially turned on. 112 in order.

  Subsequently, the switch unit 100 that has determined that the switch control signal CNT targets itself switches on its own switch 74 and notifies the switch control unit 52 of the result (step S230). For example, the switch unit 111 and the switch unit 112 turn on their own switches 74 and notify the switch control unit 52 of the result.

Subsequently, in response to the notification received from the switch unit 100, the switch control unit 52 causes the control panel 53 to display the state of the switch unit 100 included in the notification. The control panel 53 displays the state of the switch unit 100 on the display screen 53a of the control panel 53 (step S240). For example, when the switch unit 111 and the switch unit 112 are turned on, the control panel 53 displays the area of the switch unit 111 and the switch unit 112 in “red”.
By performing opening / closing control of the desired switch unit 100 by the above power supply processing, the power supply range in the power supply path can be set.

  Note that as a modification of the above, in a state where the switch unit 111 and the switch unit 112 are open, the switch control in the power supply device 50 is performed when the user directly designates the switch unit 112 and inputs the switch unit 112. The unit 52 may automatically execute turning on of the switch unit 111 and turning on of the switch unit 112 in order.

  Similarly, when power is supplied to the load device L14 and the load device L15 in a power failure state of the DC power supply device 20, the switch control unit 52 directly designates the switch unit 115 to instruct to turn on the switch device 52. Alternatively, the switch unit 114 may be automatically turned on and the switch unit 115 may be turned on sequentially.

Thus, on the control panel 53, the user instructs the switch unit 116 to open and close from the power supply paths P <b> 11 and N <b> 11 to the power supply paths P <b> 28 and N <b> 28. It is possible to set the range of the power supply path to be supplied.
Accordingly, when the user cannot supply power from the DC power supply device 20 to the load device at the time of a power failure of the DC power supply device 20 and supplies power from the solar power generation device 30, the switch unit on the control panel 53 By instructing the opening and closing of the switch unit 116 from 111, a load device that can supply power from the solar power generation device 30 can be selected. In addition, the range of load devices that supply power can be sequentially expanded in accordance with the power supply capability of the solar power generation device 30.

(Example of startup screen of PCS 40 on control panel 53)
In addition, the above-described activation button of the PCS 40 can be arranged on the control panel 53.
FIG. 9 is an explanatory diagram illustrating an example of a startup screen of the PCS 40 on the control panel 53.
In the example shown in FIG. 9, “PCS 40 activation condition display section 57”, “activation button 55 </ b> A” indicating the position where the activation operation is detected, and PCS 40 are activated on touch-panel display screen 56. A “display lamp 58” indicating this is arranged.

  The start condition display unit 57 includes display lamps 57a to 57d for displaying whether or not a start condition necessary for starting the PCS 40 is satisfied. The activation conditions of the PCS 40 include two determination conditions: a condition “the circuit breaker 11 is open” shown in (1) and a condition “output state of the photovoltaic power generator (PV)”. In the start condition display section 57, whether or not each condition is satisfied is indicated by a color of a region surrounded by a broken line.

The condition of “breaker 11 is open” shown in (1) is a condition for detecting that a reverse power flow does not occur from the power supply path toward the commercial power system 2. For example, it is detected whether or not a contact signal Aux indicating that the circuit breaker (CB) 11 is open is input to the power supply device 50.
When the condition of “breaker 11 is open” is satisfied, for example, the color of the area surrounded by the broken line of the display lamp (OK) 57a is displayed as “green”, and the broken line of the display lamp (NO) 57b. The color of the surrounding area is displayed in “gray”. On the other hand, when the condition of “breaker 11 is open” is not satisfied, the color of the area surrounded by the broken line of the display lamp (OK) 57a is displayed as “gray” and surrounded by the broken line of the display lamp (NO) 57b. The color of the area is displayed in “red”.

Moreover, the condition of “output state of the solar power generation device 30” shown in (2) is a condition for detecting whether or not electric power of a predetermined value or more can be supplied from the solar power generation device 30 to the power supply path.
When the condition of the “output state of the solar power generation device 30” is satisfied, for example, the color of the area surrounded by the broken line of the display lamp (OK) 57c is displayed in “green” and the display lamp (NO) 57d. The color of the area surrounded by the broken line is displayed in “gray”. On the other hand, when the condition of “output state of photovoltaic power generation device 30” is not satisfied, the color of the area surrounded by the broken line of the display lamp (OK) 57c is displayed in “gray”, and the display lamp (NO) 57d The color of the area surrounded by the broken line is displayed in “red”.

When both the condition of “breaker 11 is open” and the condition of “output state of solar power generation device 30” are satisfied, a portion surrounded by a solid line of start button 55A is, for example, “ “Green” blinks to indicate that the user's operation can be accepted.
On the other hand, if any of the conditions of “the circuit breaker 11 is open” and “the output state of the photovoltaic power generation device 30” is not satisfied, the portion surrounded by the solid line of the start button 55A is, for example, , “Gray”, and the user cannot accept the operation.

Then, when both the condition of “breaker 11 is open” and the condition of “output state of solar power generation device 30” are satisfied, by operating the area indicated by the solid line of start button 55A, The supply device 50 activates the PCS 40. When the PCS 40 is activated, an area indicated by a broken line of the display lamp 58 indicating that the PCS 40 is activated changes from, for example, “gray” to “orange”.
Thereby, when starting PCS40, the user can confirm that the starting conditions of PCS40 are satisfied, and can operate starting button 55A of PCS40. Further, the user can visually confirm that the PCS 40 is activated by the display lamp 58.
In the example shown in FIG. 9, the two conditions of “the circuit breaker 11 is open” and “the output state of the photovoltaic power generator 30” are used as the activation conditions of the PCS 40. These conditions can also be added. For example, the PCS 40 activation condition may include a condition in which no failure has occurred in the power supply path.

As described above, in the DC power supply system 1 according to the first embodiment, the example in which the commercial power system 2 detects a power failure by the undervoltage relay of the protective relay 13 has been described. However, the commercial power system 2 has a power failure. As a method for detecting this, for example, a voltage sensor (voltage detection relay) may be provided on the secondary side of the transformer 12, and it may be detected by this voltage sensor that the commercial power system 2 has failed.
In addition, a voltage sensor and a voltage detection circuit for detecting that the commercial power system 2 has failed in the DC power supply device 20 are provided, and this voltage sensor and voltage detection circuit detects that the commercial power system 2 has failed. Also good.
Furthermore, the DC power supply device 20 may be provided with an overcurrent relay function, a ground fault relay function, and an undervoltage relay function. That is, the protective relay 13 described above can be included in the DC power supply device 20.
Further, when it is detected by a voltage sensor or the like that the commercial power system 2 is in a power failure state, the power supply device 50 detects that the start button 55 of the PCS 40 has been operated without opening the circuit breaker 11. In some cases, the circuit breaker 11 may be opened.

  Further, when the DC power supply device 20 is configured by a unidirectional AC / DC converter having no power regeneration function and there is no possibility of reverse power flow from the power supply paths P11 and N11 toward the commercial power system 2, The power supply device 50 can activate the PCS 40 without detecting the open state of the circuit breaker 11 when the PCS 40 is activated.

[Second Embodiment]
In the DC power supply system 1 of the first embodiment described above, the start button 55 is operated when the PCS 40 is started. However, as the DC power supply system 1A of the second embodiment, the start button 55 is used. An example in which the PCS 40 is automatically activated without operating the button will be described.

  FIG. 10 is a configuration diagram showing a schematic configuration of a DC power supply system 1A according to the second embodiment of the present invention. The DC power supply system 1A shown in FIG. 10 differs from the DC power supply system 1 shown in FIG. 3 only in that the start button 55 shown in FIG. 3 is omitted in the power supply device 50A shown in FIG. The configuration of is the same as that of the DC power supply system 1 shown in FIG. For this reason, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.

The DC power supply system 1A shown in FIG. 10 opens the circuit breaker 11 and the PCS 40 when the protective relay 13 detects that a power failure state has occurred in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20. However, the operation is temporarily stopped. Subsequently, the power supply device 50A detects that no reverse power flow is generated from the power supply path toward the commercial power system 2, and restarts the PCS 40 after this detection, and power is supplied from the PCS 40 to the power supply path. Supply.
That is, in the DC power supply system 1 of the first embodiment, the start button 55 is operated as a condition for restarting the PCS 40 after the operation of the PCS 40 is temporarily stopped, but the DC power supply of the second embodiment. In the system 1A, the PCS 40 is automatically restarted without requiring the operation of the start button 55.

  FIG. 11 is a flowchart showing the procedure of the startup process of the PCS 40 at the time of a power failure of the DC power supply system 1A. The procedure for starting the PCS 40 shown in FIG. 11 omits the processing step of step S125 shown in FIG. 5 in comparison with the procedure for starting the PCS 40 in the DC power supply system 1 of the first embodiment shown in FIG. Only the points differ, and the other processing steps are the same as the processing procedure shown in FIG. For this reason, the same code | symbol is attached | subjected to the step of the same processing content, and the overlapping description is abbreviate | omitted.

That is, in the DC power supply system 1A, when the protective relay 13 detects that a power failure state in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20 (step S110), the power supply device 50A The operation of the PCS 40 is temporarily stopped (step S115), and the switch unit 101 is opened (step S120).
As a method for detecting the occurrence of a power failure in the commercial power system 2 and temporarily stopping the operation of the PCS 40, the bus voltage detection unit 51A of the power supply device 50 uses a predetermined voltage for the power supply paths P11 and N11. It is also possible to temporarily stop the operation of the PCS 40 by detecting that the voltage has decreased to a voltage value less than (for example, a value close to zero voltage). Alternatively, the PCS 40 itself may detect that the voltage of the power feeding paths P11 and N11 has decreased, and the PCS 40 may stop the operation by itself.

  Subsequently, the power supply device 50A proceeds to the processing step of step S130, and determines whether or not the solar power generation device 30 is in a state in which power of a predetermined value or more can be supplied to the power feeding path (step S130). That is, it is determined whether or not the solar power generation apparatus 30 is in a state where it can obtain a sunshine amount equal to or greater than a predetermined value, and the PCS 40 can output power equal to or greater than the predetermined value to the power feeding path.

  Subsequently, in the process of step S130, when it is determined that the photovoltaic power generation apparatus 30 is in a state where it can output electric power of a predetermined value or more (step S130: Yes), the power supply apparatus 50A proceeds to the process step of step S135. It is determined whether or not the circuit breaker 11 is in an open state (step S135).

If it is determined in step S135 that the circuit breaker 11 is in an open state (step S135: Yes), the power supply device 50A supplies an operating voltage to the PCS 40 by the PCS activation unit 51. Then, the PCS 40 is activated (step S140).
Subsequently, the power supply device 50A causes the switch control unit 52 to turn on the switch unit 101 to output DC power from the PCS 40 to the power feeding paths P11 and N11 (step S145).
Thus, in the DC power supply system 1A, when the protective relay 13 detects that a power failure state has occurred in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20, the breaker 11 is opened and the PCS 40 is opened. The PCS 40 can be automatically restarted by the power supply device 50A.

[Third Embodiment]
In the DC power supply system 1 of the first embodiment and the DC power supply system 1A of the second embodiment, the example in which only the solar power generation device 30 is provided as the backup power supply device has been described, but the third embodiment of the present invention is described. As an example, an example in which a power storage device 80 is provided in addition to the solar power generation device 30 as a backup power supply device will be described.

FIG. 12 is a configuration diagram showing a schematic configuration of a DC power feeding system 1B according to the third embodiment of the present invention.
The DC power supply system 1B shown in FIG. 12 is different from the DC power supply system 1 shown in FIG. 3 only in that a power storage device 80 and a power conditioner (PCS) 81 are newly added. This is the same as the DC power supply system 1 shown in FIG. For this reason, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.
That is, in the DC power supply system 1B, a power storage device 80 including a storage battery is connected to the power supply paths P11 and N11 via the PCS 81 and the switch unit 102. The switch unit 102 includes a switch for connecting / opening between the PCS 81 of the power storage device 80 and the power feeding paths P11 and N11. When the switch unit 102 is in the connected state, the PCS 81 is output from the DC power supply device 20. Enable to connect to

The power storage device 80 includes a secondary battery such as a lithium ion battery, a lead battery, or a nickel metal hydride battery. The power storage device 80 is charged by the power from the DC power supply device 20 via the PCS 81 during normal times when the output of the DC power supply device 20 is not in a power failure state. The power storage device 80 supplies the stored power to the power supply paths P11 and N11 via the PCS 81 at the time of a power failure of the DC power supply device 20. Note that the PCS 81 can also perform charge / discharge control of the power storage device 80 for the purpose of peak cut of electric power used in normal times.
The switch unit 102 connected to the PCS 81 is in an open (off) state when a failure occurs in the power supply paths P11 and N11, and separates the power storage device 80 from the system. The switch unit 102 is in a closed (on) state in a normal case where no failure has occurred in the power supply paths P11 and N11.
Note that, when the PCS 81 of the power storage device 80 has a protection function for cutting off the output current when a failure occurs in the power supply paths P11 and N11, the switch unit 102 can be omitted.

(Procedure for starting up PCS 40 in DC power supply system 1B)
FIG. 13 is a flowchart illustrating the procedure of the startup process of the PCS 40 at the time of a power failure in the DC power supply system 1B.
Compared with the procedure for starting the PCS 40 shown in FIG. 5, the procedure for starting the PCS 40 shown in FIG. 13 includes a processing step in step S110A, a processing step in step S135A, and a processing step in step S140A. The other processing steps are the same as the processing procedure shown in FIG. For this reason, the same code | symbol is attached | subjected to the step of the same processing content, and the overlapping description is abbreviate | omitted.

In the procedure of the start-up process shown in FIG. 13, it is assumed that a power failure state has occurred in the DC power supply system 1B in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20.
When a power failure occurs in the commercial power system 2, the circuit breaker 11 in the power receiving facility 10 is opened by the operation of an undervoltage relay (not shown) in the protective relay 13, and the auxiliary contact 11a of the circuit breaker 11 is opened. The power supply device 50 detects that the auxiliary contact 11a of the circuit breaker 11 has been opened based on the contact signal Aux, and detects that a power failure has occurred in the commercial power system 2 (step S110).

Subsequently, the power supply device 50 controls the PCS 81 of the power storage device 80 to start discharging from the power storage device 80 toward the power feeding paths P11 and N11 (step S110A), and temporarily stops the operation of the PCS 40 ( Step S115). Further, the power supply device 50 opens the switch unit 101 (step S120).
Subsequently, the power supply device 50 determines whether or not the activation button 55 that activates the PCS 40 has been operated (step S125), and when it is determined that the activation button 55 has been operated (step S125: Yes), sunlight It is determined whether or not the power that can be output from the power generation device 30 is equal to or greater than a predetermined value (step S130).

  Subsequently, in the process of step S130, when it is determined that the photovoltaic power generation apparatus 30 is in a state in which power greater than or equal to a predetermined value can be output to the power supply path (step S130: Yes), the power supply apparatus 50 performs the process of step S135. It transfers to a process step and it is determined whether the circuit breaker 11 exists in the open state (step S135).

  And when it determines with the circuit breaker 11 being in the open state in the process of step S135 (step S135: Yes), the power supply device 50 causes the DC voltage of the power supply paths P11 and N11 by the bus voltage detector 51A. Is within a predetermined reference voltage range (for example, within ± 10% of the rated voltage) (step S135A).

  In the process of step S135A, when it is determined that the DC voltage of the power supply paths P11 and N11 is not within the predetermined reference voltage range (step S135A: No), the power supply device 50 serves as a reference for starting the PCS 40. The operating voltage is supplied to the PCS 40 and the PCS 40 is activated independently (step S140). In other words, the power supply device 50 supplies the operating voltage that enables the PCS 40 that has stopped outputting to be output from the PCS 40 without detecting the voltages of the power supply paths P11 and N11, and starts the PCS 40 independently. Let

On the other hand, in the process of step S135A, when it is determined that the DC voltage of the power feeding paths P11 and N11 is within the predetermined reference voltage range (step S135A: Yes), that is, the DC power is transferred from the power storage device 80 to the power feeding paths P11 and N11. When the voltage is output, the power supply device 50 activates the PCS 40 so as to be linked to the DC voltage of the power supply paths P11 and N11 (step S140A).
When the PCS 40 detects and connects to the DC voltage output from the power storage device 80 to the power supply paths P11 and N11, the DCS output from the PCS 40 to the power supply paths P11 and N11 is transmitted from the PCS 81 of the power storage device 80. By setting the voltage higher than the output DC voltage by a predetermined amount (for example, a voltage 1% to several% higher), the PCS 40 can be naturally linked to the power feeding paths P11 and N11.

  As described above, in the DC power supply system 1B of the third embodiment, power can be supplied from the power storage device 80 to the power supply paths P11 and N11 via the PCS 81 during the power failure of the DC power supply device 20, and the start button 55 is operated. Thus, the PCS 40 can be activated independently, and power can be supplied from the solar power generation device 30 to the power feeding paths P11 and N11 via the PCS 40.

[Fourth Embodiment]
In the DC power supply system 1B of the third embodiment described above, it is a condition that the start button 55 is operated when starting the PCS 40. However, as the DC power supply system 1C of the fourth embodiment, the start button 55 An example in which the PCS 40 is automatically activated without operating the button will be described.
FIG. 14 is a configuration diagram showing a schematic configuration of a DC power feeding system 1C according to the fourth embodiment of the present invention.
14 is different from the DC power supply system 1B shown in FIG. 12 only in that the start button 55 shown in FIG. 12 is omitted in the power supply device 50A shown in FIG. The configuration of is the same as that of the DC power supply system 1B shown in FIG. For this reason, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.

In the DC power feeding system 1C according to the fourth embodiment of the present invention shown in FIG. 14, when the protective relay 13 detects that a power failure state has occurred in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20, While opening the circuit breaker 11, the PCS 40 temporarily stops its operation, and supplies power from the power storage device 80 to the power feeding paths P11 and N11 via the PCS 81.
Subsequently, the power supply device 50A detects that there is no reverse power flow from the power supply path toward the commercial power grid 2, and automatically restarts the power conditioner 40 after this detection. , Power is supplied from the PCS 40 to the power supply path.

That is, in the DC power supply system 1B of the third embodiment, it is a condition that the start button 55 is operated when starting the power conditioner 40, but in the DC power supply system 1C of the fourth embodiment, The power conditioner 40 is automatically activated without requiring the activation button 55 to be operated.
As described above, in the DC power supply system 1C of the fourth embodiment, power can be supplied from the power storage device 80 to the power supply paths P11 and N11 via the PCS 81 during the power failure of the DC power supply device 20, and the start button 55 is operated. Without requiring this, the PCS 40 can be automatically activated independently, and power can be supplied from the solar power generation device 30 to the power supply paths P11 and N11 via the PCS 40.

(Procedure for starting up PCS 40 in DC power supply system 1C)
FIG. 15 is a flowchart showing the procedure of the startup process of the PCS 40 at the time of a power failure in the DC power supply system 1C. In the example shown in FIG. 15, when a power failure occurs in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20, power is supplied from the power storage device 80 to the power supply paths P <b> 11 and N <b> 11, and then the power storage device 80. This is an example in which the PCS 40 is activated when the electric charge accumulated in is insufficient or exhausted.
Hereinafter, with reference to the flowchart shown in FIG. 15, the procedure of the startup process of the PCS 40 in the DC power supply system 1C will be described.
First, it is assumed that a power failure state has occurred in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20.
When a power failure occurs in the commercial power system 2, the circuit breaker 11 in the power receiving facility 10 is opened by the operation of an undervoltage relay (not shown) in the protective relay 13, and the auxiliary contact 11a of the circuit breaker 11 is opened. The power supply device 50 detects that the auxiliary contact 11a of the circuit breaker 11 has been opened based on the contact signal Aux, and detects that a power failure has occurred in the commercial power system 2 (step S110).

  Subsequently, the power supply device 50 controls the PCS 81 of the power storage device 80 to start discharging from the power storage device 80 toward the power feeding paths P11 and N11 (step S110A), and temporarily stops the operation of the PCS 40 ( Step S115). The power supply device 50 opens the switch unit 101 (step S120). As a result, when the power supply device 50 detects that a power failure has occurred in the commercial power system 2, the power supply device 50 temporarily stops the operation of the PCS 40 and supplies power to the power supply paths P11 and N11 from the power storage device 80. Can do.

Subsequently, the power supply device 50 detects whether or not the voltage of the power feeding paths P11 and N11 has decreased to a predetermined voltage value or less (for example, a value close to zero voltage) by the bus voltage detection unit 51A (step) S125A). That is, after the power storage device 80 starts discharging, has the DC voltage supplied from the power storage device 80 to the power supply paths P11 and N11 decreased to a predetermined voltage value or less due to insufficient or depleted charge of the power storage device 80? The power supply device 50 detects whether or not.
And when it determines with the voltage of the electric power feeding path | routes P11 and N11 having fallen below the predetermined voltage value in the process of step S125A (step S125A: Yes), the power supply device 50 will perform the process step of step S130. It shifts and it is determined whether the electric power which can be output from the solar power generation device 30 is electric power more than predetermined value (step S130). That is, it is determined whether the solar power generation device 30 is in a state where it can obtain a sunshine amount equal to or greater than a predetermined value and can supply power greater than the predetermined value from the PCS 40 to the power supply path.

Subsequently, in the process of step S130, when it is determined that the photovoltaic power generation apparatus 30 is in a state in which power greater than or equal to a predetermined value can be output to the power supply path (step S130: Yes), the power supply apparatus 50 performs the process of step S135. It transfers to a process step and it is determined whether the circuit breaker 11 exists in the open state (step S135).
In the power failure detection process in step S110, the power supply device 50 has already detected that the circuit breaker 11 has been opened based on the contact signal Aux. Therefore, in the determination process in step S135, the circuit breaker 11 is opened. This is done to reconfirm that it is in progress and can be omitted.

And when it determines with the circuit breaker 11 being in the open state in the process of step S135 (step S135: Yes), the power supply apparatus 50 transfers to the process step of step S140, and the PCS starting part 51 performs it. Then, the PCS 40 is activated by supplying an operating voltage that enables the PCS 40 to output power to the PCS 40 (step S140).
Subsequently, the power supply device 50 causes the switch control unit 52 to turn on the switch unit 101 to output DC power from the PCS 40 to the power feeding paths P11 and N11 (step S145). Then, after executing the process of step S145, the power supply device 50 ends the startup process of the PCS 40.

On the other hand, in the process of step S125A, when it is determined that the voltages of the power supply paths P11 and N11 have not decreased below the predetermined voltage value (step S125A: No), the power supply device 50 proceeds to the process step of step S115. Returning, the operation stop state of the PCS 40 and the open state of the switch unit 101 are continued.
Moreover, in the process of step S130, when it determines with the solar power generation device 30 not being in the state which can output the electric power more than a predetermined value to an electric power feeding path (step S130: No), the power supply apparatus 50 will process step S115. Returning to the step, the operation stop state of the PCS 40 and the open state of the switch unit 101 are continued.
If it is determined in step S135 that the circuit breaker 11 is not open (step S135: No), the power supply device 50 returns to the processing step of step S115, and the PCS 40 operation stop state and switch The open state of the unit 101 is continued.

  As a result, in the DC power supply system 1C, when a power failure state occurs in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20, the operation of the PCS 40 is temporarily stopped and the power storage device 80 moves to the power supply paths P11 and N11. Electric power can be supplied. Thereafter, when the charge accumulated in the power storage device 80 is insufficient or depleted, the power supply device 50 can start the PCS 40 and supply power from the solar power generation device 30 to the power supply path.

(First Modification of Procedure for Start-up Process of PCS 40 in DC Power Supply System 1C)
FIG. 16 is a flowchart showing a first modification of the procedure of the startup process of the PCS 40 at the time of a power failure in the DC power supply system 1C. 16 is replaced with the process of step S125B shown in FIG. 16 in comparison with the procedure of the PCS 40 start process shown in FIG. Only the points differ, and the other processing steps are the same as the processing procedure shown in FIG. For this reason, the same code | symbol is attached | subjected to the step of the same processing content, and the overlapping description is abbreviate | omitted.

In the procedure of the start-up process shown in FIG. 16, it is assumed that a power failure state has occurred in the DC power supply system 1C in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20.
When a power failure occurs in the commercial power system 2, the circuit breaker 11 in the power receiving facility 10 is opened by the operation of an undervoltage relay (not shown) in the protective relay 13, and the auxiliary contact 11a of the circuit breaker 11 is opened. The power supply device 50 detects that the auxiliary contact 11a of the circuit breaker 11 has been opened based on the contact signal Aux, and detects that a power failure has occurred in the commercial power system 2 (step S110).

Subsequently, the power supply device 50 controls the PCS 81 of the power storage device 80 to start discharging from the power storage device 80 toward the power feeding paths P11 and N11 (step S110A), and temporarily stops the operation of the PCS 40 ( Step S115). Further, the power supply device 50 opens the switch unit 101 (step S120).
Subsequently, the power supply device 50 determines whether or not the DC voltage of the power supply paths P11 and N11 is within a predetermined reference voltage range (for example, within ± 10% of the rated voltage) by the bus voltage detector 51A. (Step S125B).

In the process of step S125B, when it is determined that the DC voltage of the power supply paths P11 and N11 is within the predetermined reference voltage range (step S125B: Yes), that is, from the power storage device 80 to the power supply paths P11 and N11. When the DC voltage is output, the power supply device 50 proceeds to the process of step S130. And in the process of step S130, when it determines with it being in the state which can supply the electric power more than a predetermined value to the electric power feeding path from the solar power generation device 30 (step S130: Yes), the power supply device 50 of step S135 It transfers to a process and it is determined whether the circuit breaker 11 exists in the open state (step S135).
And when it determines with the circuit breaker 11 being in the open state in the process of step S135 (step S135: Yes), the power supply apparatus 50 starts PCS40 by the PCS starting part 51 (step S140). .
On the other hand, in the process of step S125B, when it is determined that the DC voltage of the power supply paths P11 and N11 is not within the predetermined reference voltage range (step S125B: No), the power supply device 50 returns to the process of step S115, The operation stop state of the PCS 40 is continued.

That is, in the procedure of the startup process of the PCS 40 shown in FIG. 16, in a state where a DC voltage is output from the power storage device 80 to the power supply paths P11 and N11, the power supply device 50 uses the PCS 40 as the DC voltage of the power supply paths P11 and N11. Start it up so as to be linked to.
When the PCS 40 detects and connects to the DC voltage output from the power storage device 80 to the power supply paths P11 and N11, the DCS output from the PCS 40 to the power supply paths P11 and N11 is transmitted from the PCS 81 of the power storage device 80. By setting the voltage higher than the output DC voltage by a predetermined amount (for example, a voltage 1% to several% higher), the PCS 40 can be naturally linked to the power feeding paths P11 and N11.
Thereby, at the time of a power failure of DC power supply device 20, it is possible to supply power to power supply paths P11 and N11 in parallel from power storage device 80 and solar power generation device 30.

(Second modified example of the procedure of starting the PCS 40 in the DC power supply system 1C)
In the example of the startup processing procedure shown in FIGS. 15 and 16, the power supply device 50 detects a signal (for example, a contact signal Aux) indicating a power failure state in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20. In this case, the example in which the operation of the PCS 40 is stopped has been described. However, the power supply device 50 detects that the voltages of the power supply paths P11 and N11 serving as power supply buses have decreased to a predetermined voltage value or less, for example, power supply The operation of the PCS 40 may be stopped by detecting that the DC voltage of the paths P11 and N11 has a value close to zero voltage.

FIG. 17 is a flowchart showing a second modification of the procedure of the PCS 40 activation process.
In comparison with the procedure for starting the PCS 40 shown in FIG. 16, the procedure for starting the PCS 40 shown in FIG. 17 omits the processing in step S110A from the procedure shown in FIG. 16, and the processing in steps S110B and S120A is performed. The newly added process is different, and the other processing is the same as the processing procedure shown in FIG. For this reason, the same code | symbol is attached | subjected to the step of the same processing content, and the overlapping description is abbreviate | omitted.

In the procedure of the start-up process shown in FIG. 17, when the protective relay 13 detects that a power failure state has occurred in which the DC power supply system 1C cannot supply power from the commercial power system 2 to the DC power supply device 20 (step). S110), the circuit breaker 11 is opened, but at this time, the power supply device 50 does not supply DC power from the power storage device 80 to the power feeding paths P11 and N11.
Subsequently, the power supply device 50 detects the DC voltage of the power supply paths P11 and N11 by the bus voltage detector 51A, and the DC voltage of the power supply paths P11 and N11 decreases below a predetermined voltage value due to a power failure of the DC power supply device 20. It is determined whether or not (step S110B). When it is determined that the DC voltage of the power supply paths P11 and N11 has decreased to a predetermined voltage value or less (step S110B: Yes), the power supply device 50 temporarily stops the operation of the PCS 40 (step S115). ), The switch unit 101 is opened (step S120).
Subsequently, the power supply device 50 controls the PCS 81 to start supplying power from the power storage device 80 to the power feeding paths P11 and N11 (step S120A).

The subsequent processing procedure is the same as the processing procedure from step S125B to step S145 shown in FIG.
Thereby, at the time of a power failure of the DC power supply device 20, the power supply device 50 can detect that the DC voltage of the power supply paths P11 and N11 serving as power supply buses has decreased, and can stop the operation of the PCS 40.
Note that the PCS 40 itself may detect that the DC voltage of the power supply paths P11 and N11 has decreased, and the PCS 40 may stop the operation by itself.

  As a further modification of the DC power supply system 1C of the fourth embodiment, when a power failure occurs in the DC power supply device 20, the PCS 40 supplies power from the power storage device 80 via the PCS 81 without stopping its operation. The operation may be continued as it is linked to the DC voltage output to the paths P11 and N11. However, when continuing the operation of the PCS 40, the power supply device 50A detects from the contact signal Aux that there is no reverse power flow from the power supply path toward the commercial power system 2, and this reverse power flow If it is detected that the state does not occur, the operation of the PCS 40 is continued as it is. On the other hand, the power supply device 50A stops the operation of the PCS 40 when it is detected that there is a possibility that reverse power flow from the power supply path toward the commercial power system 2 occurs.

As described above, as the DC power supply system of the present invention, the DC power supply system 1 of the first embodiment, the DC power supply system 1A of the second embodiment, the DC power supply system 1B of the third embodiment, and the DC power supply of the fourth embodiment. The system 1C has been described.
In these DC power supply systems, the PCS 40 is not required to detect the voltages of the power supply paths P11 and N11 that are buses to which the PCS 40 is connected, and the PCS 40 is not limited to the power supply device 50 or 50A. By receiving the supply of the operating voltage from, the operation can be performed without detecting the voltages of the power feeding paths P11 and N11. That is, the PCS 40 can continue the output of the DC power as it is even when the voltage of the power supply paths P11 and N11 is reduced.

Further, as a condition at the time of starting up the PCS 40, in addition to a condition in which a power failure state in which power cannot be supplied from the commercial power system 2 to the DC power supply device 20 has occurred, the start condition is that the voltages of the power supply paths P11 and N11 have disappeared. May be included.
Further, as in the DC power supply system 1B of the third embodiment and the DC power supply system 1C of the fourth embodiment, the DC power supply system includes the power storage device 80. When supplying DC power to the power supply paths P11 and N11 from the battery of the battery, a predetermined SOC (State of Charge) is used without depleting the battery charge in the power storage device 80 so that the battery can be started when the DC power supply system is blacked out. ) May be secured. That is, when the SOC of the battery of the power storage device 80 is equal to or lower than the predetermined SOC, the discharge from the power storage device 80 to the power feeding paths P11 and N11 may be stopped.

[Example of AC power supply system]
In the first to fourth embodiments, the example of the DC power supply system that supplies DC power to the load device connected to the power supply path has been described. However, AC power supply that supplies AC (for example, AC 400 V) to the load device is described. It may be a system.
FIG. 18 is a configuration diagram illustrating a schematic configuration of the AC power feeding system 1D. The AC power supply system 1D shown in FIG. 18 has the same basic configuration as that of the DC power supply system 1 shown in FIG. 1, but the DC power supply device 20 shown in FIG. The point which replaced with the power conditioner 40A which outputs an alternating voltage differs on a structure.
Also, the DC voltage feed paths P11 and N11 shown in FIG. 1 are replaced with a three-phase AC voltage feed path ACL11, and the feed paths P21 and N21 to P28 and N28 are replaced with a three-phase or single-phase feed path ACL21 to ACL28. Different points. In FIG. 18, switch units 101 to 116 are semiconductor switches having a function of conducting and blocking alternating current, and load devices L11 to L16 are load devices that receive a three-phase or single-phase alternating voltage as input. is there.

  In the AC power supply system 1D having the above-described configuration, the transformer 12 reduces the high-voltage AC voltage (for example, three-phase AC 6600V) supplied from the commercial power system 2 to a predetermined low-voltage AC voltage (for example, three-phase AC 400V). The AC voltage is output to the power supply path ACL11.

The solar power generation device 30 is connected to the power supply path ACL11 via a power conditioner (PCS) 40A and a switch unit 101. The PCS 40A of the solar power generation device 30 includes a power conversion device such as a DC / AC converter (inverter) or a PCS transformer that boosts alternating current to a predetermined voltage.
The control operation in the AC power supply system 1D is different only in that the DC voltage in the DC power supply system 1 shown in FIG. 1 is replaced with an AC voltage, and the basic operations of the power supply device 50, the PCS 40A, the switch unit 100, and the like are The operation is the same as that in the DC power supply system 1 shown in FIG.

That is, at the time of a power failure of the commercial power system 2, the power supply device 50 temporarily stops the operation of the PCS 40A, and when the start button 55 is operated, supplies a reference AC operating voltage to the PCS 40A. Is activated independently. Further, the power supply device 50 sets the open / close state of the switch units 111 to 116, and sets the power supply range in the power supply paths ACL11 to ACL28.
In addition, about a detailed structure and control operation | movement, since it is the same as that of the case of the DC power supply system 1, the overlapping description is abbreviate | omitted.
Thereby, in AC power supply system 1D, in a power failure state in which AC power is not supplied from commercial power system 2 to the power supply path, AC power can be supplied from the solar power generation device to the power supply path.

The embodiment of the present invention has been described above. In the above embodiment, the functions of the processing units in the power supply device 50 and the power supply device 50A may be realized by dedicated hardware. The program for realizing the function of each processing unit is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read by a computer system and executed to realize the function. There may be.
That is, the power supply devices 50 and 50A have a computer system inside. A series of processes related to the above-described process is stored in a computer-readable recording medium in the form of a program, and the above-described process is performed by the computer reading and executing this program. Here, the computer-readable recording medium refers to a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, and the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program. The “computer system” here includes an OS and hardware such as peripheral devices.

Here, the correspondence between the present invention and the above-described embodiment will be supplementarily described. The DC power supply system according to the present invention corresponds to the DC power supply system 1, the DC power supply system 1A, the DC power supply system 1B, or the DC power supply system 1C.
The DC power supply device 20 corresponds to the DC power supply device in the present invention.
The power supply device according to the present invention corresponds to the power supply device 50 or the power supply device 50A, and the power conditioner according to the present invention corresponds to the power conditioner (PCS) 40. In addition, the detection unit in the present invention corresponds to the protection relay 13, and more specifically, the power supply by the contact signal of the auxiliary contact 11 a of the circuit breaker 11 operated by the signal output from the undervoltage relay in the protection relay 13. Supply device 50 detects a state in which DC power is not supplied from DC power supply device 20 to the power supply path. The control unit in the present invention corresponds to the PCS activation unit 51 of the power supply device 50. The control unit may be the grid interconnection control unit 42 of the PCS 40. Moreover, the circuit breaker 11 respond | corresponds to the interruption | blocking part in this invention.

  (1) In the above embodiment, the DC power supply system 1 (DC power supply system) is provided with a DC power supply device 20 that converts AC power supplied from the commercial power system 2 into DC power. Protective relay 13 (detection unit) that detects a state in which DC power is not supplied from the DC power supply device 20 to the power supply path in the DC power supply system 1 that supplies DC power to the load device via the path, and the detection result And a power supply device 50 (control unit) that controls the supply of DC power to the power supply path, and the PCS 40 (power conditioner) converts the power generated by the solar power generation device 30 into DC power. The power supply path is configured such that the DC power converted by the PCS 40 is supplied to the power supply path in accordance with the control of the power supply apparatus 50. , After the DC power is detected by the protective relay 13 states that are not supplied to the power supply path from the DC power supply unit 20, and controls to supply the DC power from PCS40 to the feed path.

In the DC power supply system 1 (DC power supply system) having such a configuration, the protective relay 13 (detection unit) detects a state in which the commercial power system 2 is in a power failure state and DC power is not supplied from the DC power supply device 20 to the power supply path. Later, the power supply device 50 supplies DC power from the PCS 40 to the power supply path.
Thereby, DC power can be supplied from the solar power generation device 30 to the power supply path in a power failure state in which DC power is not supplied from the DC power supply apparatus 20 to the power supply path.
In the DC power supply system 1 (DC power supply system), power is directly supplied from the PCS 40 to the power supply path. In short, the DC power supply system 1 does not require a configuration in which the power supplied from the PCS 40 is stored and then the stored power is supplied to the load. With this configuration, the DC power supply system 1 supplies DC power from the solar power generation device 30 to the power supply path via the PCS 40 without storing power from the solar power generation apparatus, and passes through the power supply path. The power can be supplied to the load.

(2) In the above embodiment, the DC power supply system 1 (DC power supply system) cuts off the supply of power from the power supply path toward the commercial power system 2 so that no reverse power flow occurs in the commercial power system 2. The power supply device 50 (control unit) includes a circuit breaker 11 (a circuit breaker) that is detected by the protective relay 13 (detection unit) when no DC power is supplied from the DC power supply device 20 to the power feeding path. When DC power is supplied from the PCS 40 (power conditioner) to the power supply path according to the control by 50, the circuit breaker 11 cuts off the supply of power from the power supply path to the commercial power system.
In the DC power supply system 1 (DC power supply system) having such a configuration, the circuit breaker 11 (shuts off the supply of power from the power supply path toward the commercial power system 2 so that a reverse power flow does not occur in the commercial power system 2. A blocking section). When the DC power is supplied from the PCS 40 (power conditioner) to the power supply path, the power supply device 50 (control unit) cuts off the power supply from the power supply path toward the commercial power system by the circuit breaker 11. Let
Thus, in the DC power supply system 1 (DC power supply system), when DC power is supplied from the PCS 40 (power conditioner) to the power supply path, the supply of power from the power supply path to the commercial power system 2 is interrupted. 11 can be blocked.

(3) In the above embodiment, the circuit breaker 11 (breaker) is provided between the power receiving point of the commercial power system 2 and the DC power supply device 20.
Thereby, supply of electric power from the DC power supply device 20 toward the commercial power system 2 can be interrupted by the circuit breaker 11.

  (4) Moreover, in the said embodiment, operation | movement of PCS40 (power conditioner) that converts the electric power which the solar power generation device 30 generated, and supplies the direct-current power after conversion to a feed route, direct-current power supply device After the protective relay 13 (detection unit) detects a state in which DC power is not supplied from 20 to the power supply path, the power supply device 50 (control unit) temporarily stops. Then, the power supply device 50 suspends the operation of the PCS 40 and then detects that the power supply to the commercial power system 2 is cut off and is in a state of cutting off the power supply. After detecting this, the PCS 40 is controlled so that the PCS 40 whose operation has been temporarily stopped is restarted, and after the PCS 40 is restarted, DC power is supplied from the PCS 40 to the power supply path.

In the DC power supply system 1 (DC power supply system) having such a configuration, after the protective relay 13 (detection unit) detects a state in which DC power is not supplied from the DC power supply device 20 to the power supply path, the operation of the PCS 40 is temporarily stopped. . Then, the power supply device 50 detects that the circuit breaker 11 is open after detecting that it is in a state of avoiding the occurrence of reverse power flow from the power supply path toward the commercial power system 2, for example. After detection by the contact signal Aux, the PCS 40 is restarted, and power is supplied from the PCS 40 to the power feeding path.
Thus, in the DC power supply system 1 (DC power supply system), in a power failure state in which DC power is not supplied from the DC power supply device 20 to the power supply path, the operation of the PCS 40 is temporarily stopped, and then the PCS 40 is restarted. DC power can be supplied from the power generation device 30 to the power supply path.

(5) Moreover, in the said embodiment, when the protection relay 13 (detection part) detects the state where DC power is not supplied to the electric power feeding path from the DC power supply device 20 (control part), the power supply apparatus 50 (control part) PCS40 ( The operation of the inverter is temporarily stopped, and after the operation of the PCS 40 is temporarily stopped, it is detected that an operation for instructing the activation of the PCS 40 is performed, and the detection result of the operation for instructing the activation is detected. The PCS 40 is restarted.
In the DC power supply system 1 (DC power supply system) having such a configuration, when the protective relay 13 detects a state in which DC power is not supplied from the DC power supply device 20 to the power supply path, the operation of the PCS 40 is temporarily stopped. Then, after temporarily stopping the operation of the PCS 40, the power supply device 50 detects that the start button 55 has been operated, restarts the PCS 40, and supplies power from the PCS 40 to the power supply path.
Thus, in the DC power supply system 1 (DC power supply system), in a power failure state where DC power is not supplied from the DC power supply device 20 to the power supply path, the operation of the PCS 40 is temporarily stopped and then the start button 55 is operated. The PCS 40 can be restarted to supply DC power from the solar power generation device 30 to the power feeding path.

(6) In the above embodiment, the power supply device 50 (control unit) detects that an operation for instructing activation of the PCS 40 (power conditioner) has been performed, and then enters the power supply path from the DC power supply device 20. The PCS 40 is restarted when both the detection of a state in which DC power is not supplied and the fact that the power that can be output from the photovoltaic power generator 30 is equal to or greater than a predetermined value are satisfied.
Thereby, in the DC power supply system 1 (DC power supply system), when the power supply device 50 detects that the start button 55 is operated, a reverse power flow from the power supply path to the commercial power system 2 occurs. It is possible to avoid this, and it is possible to restart the PCS 40 by detecting that the power that can be output from the solar power generation device 30 is greater than or equal to a predetermined value.

(7) In the above embodiment, the DC power supply system 1 (DC power supply system) allows the PCS 40 to output power when the PCS 40 (power conditioner) is started from a stopped state. A power supply device 50 is provided for supplying an operating voltage to activate the PCS 40.
As described above, in the DC power supply system 1 (DC power supply system), in the event of a power failure of the DC power supply device 20, in order to restart the PCS 40 that has once stopped its operation, an operating voltage that allows power to be output from the PCS 40 To start the PCS 40 independently.
As a result, in the DC power supply system 1 (DC power supply system), the PCS 40 is independently activated in a power failure state in which the operating voltage enabling the operation of the PCS 40 of the photovoltaic power generation apparatus 30 is not supplied from the power supply path, and the power supply path Can be powered.

(8) In the above embodiment, the DC power supply system 1 (DC power supply system) includes the protective relay 13 (detection unit), the DC power supply device 20, the power supply device 50 (control unit), and the solar power generation device. 30 and PCS40 (power conditioner).
The DC power supply system 1 (DC power supply system) having such a configuration includes a protective relay 13 (detection unit), a DC power supply device 20, a power supply device 50 (control unit), a solar power generation device 30, and a PCS 40 ( Power supply after the commercial power system 2 detects that the commercial power system 2 is in a power failure state and no DC power is supplied from the DC power supply device 20 to the power supply path. The device 50 supplies DC power from the PCS 40 to the power supply path.
As a result, in the DC power supply system 1 (DC power supply system), the PCS 40 is independently activated in a power failure state in which the operating voltage enabling the operation of the PCS 40 of the photovoltaic power generation apparatus 30 is not supplied from the power supply path, and the power supply path Can be powered.

  Although the embodiments of the present invention have been described above, the DC power feeding system of the present invention is not limited to the above illustrated examples, and various modifications can be made without departing from the scope of the present invention. Of course.

  For example, in the DC power supply system 1 and the DC power supply system 1A, an example in which the solar power generation device 30 is installed as a power supply device for backup is shown. In the DC power supply system 1B and the DC power supply system 1C, as a power supply device for backup. Although the example in which the solar power generation device 30 and the power storage device 80 are installed has been shown, the present invention can be suitably applied even when a fuel cell, an engine generator, or the like is further installed as a backup power source. Is.

  Further, the example of opening and closing the switch unit 100 using the control panel 53 shown in FIG. 6 is an example, and other control methods for specifying and opening the switch unit 100 on the power supply path are shown. May be used. Further, the example in which the PCS 40 is activated using the control panel 53 shown in FIG. 9 is also an example, and the activation button of the PCS 40 may be performed by using a mechanical switch. Other activation instruction methods may be used.

1, 1A, 1B, 1C ... DC power supply system, 1D ... AC power supply system,
2 ... Commercial power system, 10 ... Power receiving equipment,
11 ... circuit breaker (breaker), 13 ... protective relay (detector),
20 ... DC power supply, 21 ... AC / DC converter,
30 ... Solar power generation device (PV), 40 ... Power conditioner (PCS),
41 ... Power generation amount control unit, 42 ... System interconnection control unit,
43 ... DC / DC converter,
50 ... Power supply device (control unit), 51 ... PCS activation unit,
51A ... bus voltage detector, 52 ... switch controller,
53 ... Control panel, 54 ... Storage battery,
55, 55A ... start button, 61 ... distribution board (PDF),
71 ... Switch control signal receiving unit, 72 ... Switch opening / closing unit,
73... Open / close result notification unit, 74... Switch, 75.
80 ... Power storage device, 81 ... Power conditioner (PCS),
100, 101-116 ... switch part,
Aux ... contact signal, L11-L16 ... load device,
P11, P21 to P28, N11, N21 to N28 ... Feeding path

Claims (11)

A direct current power supply system provided with a direct current power supply device that converts alternating current power supplied from a commercial power system into direct current power, and that supplies direct current power from the direct current power supply device to a load device via a feed path,
A detection unit for detecting a state in which the DC power is not supplied from the DC power supply device to the power supply path;
A control unit for controlling the supply of DC power to the power supply path based on the detected result;
With
The power supply path is configured so that the power generated by the photovoltaic power generation device is converted into DC power by a power conditioner, and the DC power after the power conditioner is converted is supplied in accordance with the control of the control unit. Has been
The controller is
The direct current power from the power conditioner is controlled to be supplied to the power supply path after the detection unit detects that the DC power is not supplied from the DC power supply device to the power supply path. Power supply system. In order to prevent a reverse power flow from occurring in the commercial power system, the power supply path includes a blocking unit that blocks power supply from the power supply path toward the commercial power system,
The controller is
When the detection unit detects a state in which the DC power is not supplied from the DC power supply device to the power supply path, and DC power is supplied from the power conditioner to the power supply path according to control by the control unit, The DC power supply system according to claim 1, wherein the power supply path from the power supply path to the commercial power system is cut off by the cut-off unit. The blocking part is
The DC power supply system according to claim 2, wherein the DC power supply system is provided between a power receiving point of the commercial power system and the DC power supply device. The operation of the power conditioner that converts the power generated by the photovoltaic power generation apparatus and supplies the converted DC power to the power supply path is supplied from the DC power supply apparatus to the power supply path. After the detection unit detects a state that is not done, the control unit temporarily stops,
The control unit, after temporarily stopping the operation of the power conditioner, detects that the supply of power toward the commercial power system is cut off, and cuts off the supply of power After the power conditioner is restarted, the inverter is controlled from the power conditioner after the power conditioner is restarted. The DC power supply system according to any one of claims 1 to 3, wherein the DC power is supplied to a power supply path. The controller is
When the detection unit detects a state in which the DC power is not supplied from the DC power supply device to the power supply path,
While temporarily stopping the operation of the inverter,
After the operation of the power conditioner is temporarily stopped, it is detected that an operation for instructing activation of the power conditioner is performed, and the power conditioner is restarted according to a detection result of the instructed operation. The DC power feeding system according to claim 4, wherein the DC power feeding system is activated. The controller is
After detecting that an operation for instructing activation of the inverter is performed,
Detecting a state in which the DC power is not supplied from the DC power supply device to a power supply path;
The power that can be output from the photovoltaic power generator is a power that is a predetermined value or more,
The DC power supply system according to claim 5, wherein when the two are satisfied, the power conditioner is restarted. When the inverter is started from a state where the operation is stopped,
The power supply apparatus which supplies the operating voltage which makes it possible to output electric power from the said power conditioner, and starts this power conditioner is provided, The power supply apparatus characterized by the above-mentioned. The described DC power supply system. The detection unit;
The DC power supply device;
A power supply device including the control unit;
The solar power generation device;
The inverter,
The DC power supply system according to claim 7, further comprising: A power supply device in a direct current power supply system that is provided with a direct current power supply device that converts alternating current power supplied from a commercial power system into direct current power, and that supplies direct current power from the direct current power supply device to a load device via a power supply path. ,
A controller for controlling the supply of DC power to the power supply path,
The DC power supply system is
A detection unit for detecting a state in which the DC power is not supplied from the DC power supply device to the power supply path;
Further, the power supply path is configured such that the power generated by the photovoltaic power generation apparatus is converted into DC power by the power conditioner, and the DC power after the power conditioner is converted is supplied in accordance with the control of the control unit. Is configured,
The controller is
The power source is controlled to supply the DC power from the power conditioner to the power supply path after the detection unit detects that the DC power is not supplied to the power supply path from the DC power supply device. Feeding device. A power supply control method in a DC power supply system, in which a DC power supply device that converts AC power supplied from a commercial power system into DC power is provided and DC power is supplied from the DC power supply device to a load device via a power supply path, ,
A procedure for detecting a state in which the DC power is not supplied from the DC power supply device to the power supply path by a detection unit;
The procedure for the power conditioner to convert the power generated by the photovoltaic power generator into DC power,
And a procedure for controlling the DC power from the power conditioner to be supplied to the power supply path after the detection unit detects that the DC power is not supplied from the DC power supply device to the power supply path. A characteristic power supply control method. A direct current power supply device that converts alternating current power supplied from a commercial power system into direct current power is provided, and direct current power is supplied from the direct current power supply device to a load device through a feed path, and from the direct current power supply device to the feed path. A detection unit that detects a state in which the DC power is not supplied is provided, and further, DC power after the power conditioner is converted is supplied from a power conditioner that converts power generated by the solar power generation device. In the computer of the DC power supply system in which the power supply path is configured,
After the detection unit detects a state in which the DC power is not supplied from the DC power supply device to the power supply path, a step of performing control to supply the DC power from the power conditioner to the power supply path is performed. program.

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