JP5543827B2 - Power system - Google Patents

Description

  The present invention relates to a power supply system that supplies electric power through interconnection with a system power supply.

  As a conventional power supply system in the above technical field, a system including a solar power generation device and another power generation device such as a fuel cell device (hereinafter referred to as “predetermined power generation device”) is known (for example, Patent Documents). 1). In such a power supply system, when the generated power of the photovoltaic power generation device exceeds the load power of the power supply target equipment, the surplus power is supplied to the system power supply and the operation of the predetermined power generation device is stopped. There is a case where a distribution board is applied as a circuit unit. The purpose of such a circuit unit is to supply the generated power of the photovoltaic power generation apparatus to the power supply target equipment with priority over the generated power of the predetermined power generation apparatus.

JP 2007-207661 A

  However, the operation of the predetermined power generation device continues even though the generated power of the photovoltaic power generation device exceeds the load power of the power supply target equipment due to some trouble or the like occurring in the circuit unit described above. If it is done, the above-mentioned purpose cannot be achieved.

  Therefore, an object of the present invention is to provide a power supply system capable of preventing the operation of the power supply system from being continued in a state where some trouble or the like has occurred in the circuit unit.

In order to solve the above-described problem, a power supply system according to the present invention is a power supply system that supplies electric power through interconnection with a system power supply, and includes a solar power generation device that generates first electric power, and second electric power. When the sum of the predetermined power generation device for generating power and the first power and the second power exceeds the load power of the power supply target facility, the surplus power corresponding to the surplus power is supplied to the system power source, and the predetermined power generation The circuit unit for reducing the second power supplied from the device to the power supply target facility, and when the first power is equal to or higher than the load power, the operation of the predetermined power generator is stopped , and the first power is the load power. in the case of less than, when the sum of the first power and the second power is greater than or equal load power, and a control unit which Ru stops the operation of the predetermined power generation device, the control unit, a first power The respective values of the second power and the load power are not passed through the circuit unit, Sunshine power generator, characterized that you get a communication from each of the predetermined power generation device and supplied power facilities.

  In this power supply system, the power (first power) generated by the photovoltaic power generation apparatus exceeds the load power of the power supply target equipment due to some trouble or the like occurring in the circuit unit. However, even if the supply of power (second power) from the predetermined power generation device to the power supply target facility is continued, the predetermined power generation device is used when the first power is larger than the load power by the control unit. Is stopped. Therefore, according to this power supply system, it is possible to prevent the operation of the power supply system from being continued in a state where some trouble or the like has occurred in the circuit unit.

At this time, the control unit, when the first power is higher load power, to stop the operation of Jo Tokoro of the generator, when the first power is less than the load power, the first power and the second power When the sum is equal to or greater than the load power, the operation of the predetermined power generator is stopped. If no malfunction or the like occurs in the above-described circuit unit, the sum of the first power and the second power is obtained when the first power is equal to or higher than the load power or when the first power is less than the load power. When the load power is equal to or higher than the load power , it is not assumed that the power supply from the predetermined power generation device to the power supply target facility is continued. Therefore, according to this control, it is possible to more reliably prevent the operation of the power supply system from being continued in a state where some trouble or the like has occurred in the circuit unit.

  The predetermined power generation device is preferably a fuel cell device. When the predetermined power generation device is a fuel cell device, it is possible to stably and efficiently supply power from the predetermined power generation device to the power supply target facility.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the power supply system which can prevent the driving | operation of a power supply system being continued in a state with a certain malfunction etc. having occurred in the circuit part.

It is a block diagram of the power supply system of the embodiment of the present invention. It is a flowchart which shows the process sequence of the control part of the power supply system of FIG. It is a block diagram of a power supply system when a malfunction arises in the distribution board of the power supply system of FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the same or an equivalent part, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 1, the power supply system 1 supplies power to the premises equipment (power supply target equipment) 20 through interconnection with the system power supply 10. As a distributed power source, the power supply system 1 includes a solar power generation device 2 that generates power (first power), a fuel cell device (predetermined power generation device) 3 that generates power (second power), and the entire system. And a control unit 11 for controlling.

  The system power supply 10 is electrically connected to the distribution board (circuit unit) 4 by the wiring L1. The premises equipment 20, the solar power generation device 2, and the fuel cell device 3 are electrically connected to the distribution board 4 by wirings L2, L3, and L4, respectively. The wirings L1 to L4 are connected so that the wiring L1 branches to the wirings L2, L3, and L4 at the connection point P1 in the distribution board 4.

  The distribution board 4 has a main breaker 7. The main breaker 7 is provided on the wiring L1. The main breaker 7 cuts off the wiring L1 when an overcurrent flows through the wiring L1, and disconnects the system power supply 10 from the power supply system 1. On the wiring L <b> 1 between the distribution board 4 and the system power supply 10, measuring instruments 5 and 6 are provided. The measuring instrument 5 measures the amount of electric power supplied to the system power supply 10 from the distribution board 4 side via the wiring L1. The measuring instrument 6 measures the amount of power supplied from the system power supply 10 to the distribution board 4 side via the wiring L1.

  Furthermore, the distribution board 4 has breakers 8a, 8b, and 8c. Breakers 8a, 8b, and 8c are provided on wirings L2, L3, and L4, respectively. The breaker 8a interrupts the wiring L2 when an overcurrent flows through the wiring L2, and disconnects the premises equipment 20 from the power supply system 1. The breaker 8b interrupts the wiring L3 when an overcurrent flows through the wiring L3, and disconnects the photovoltaic power generation apparatus 2 from the power supply system 1. The breaker 8c disconnects the wiring L4 when an overcurrent flows through the wiring L4, and disconnects the fuel cell device 3 from the power supply system 1.

  The distribution board 4 has a current sensor 9. The current sensor 9 is, for example, a current transformer (CT), and is provided on the wiring L1 between the main breaker 7 and the measuring instruments 5 and 6. When the current sensor 9 detects a current flowing through the wiring L1 when power is supplied to the system power supply 10 from the distribution board 4 side (hereinafter referred to as “reverse power flow”), the current sensor 9 is provided in the fuel cell device 3. The power supplied from the fuel cell device 3 to the distribution board 4 side is reduced by reverse power relays (RPR). At this time, depending on the case, the operation of the fuel cell device 3 is stopped, or an error is displayed for the fuel cell device 3. Thus, the current sensor 9 functions as a reverse power flow prevention device.

  The solar power generation device 2 has a solar cell panel and a power conditioner. The solar cell panel outputs direct-current power using sunlight energy. The power conditioner converts DC power output from the solar cell into AC power. Thereby, the solar power generation device 2 outputs alternating current power to the distribution board 4 side via the wiring L3.

  The fuel cell device 3 includes a reformer, a fuel cell, and a power conditioner. The reformer reforms hydrocarbon fuel such as LP gas, city gas, and kerosene to generate reformed gas containing hydrogen. The fuel cell outputs DC power by a power generation reaction using the reformed gas and air generated by the reformer. The power conditioner converts DC power output from the fuel cell into AC power. As a result, the fuel cell device 3 outputs AC power to the distribution board 4 side via the wiring L4.

  The operation of the power supply system 1 configured as described above will be described. Here, as an example, it is assumed that the solar power generation device 2 generates 3000 W of power and the fuel cell device 3 generates 700 W of power.

  First, when the load power of the premises equipment 20 is 5000 W, the 3000 W power generated by the solar power generation device 2 is supplied to the premises equipment 20 via the wiring L3 and the wiring L2, and is generated by the fuel cell device 3. Further, 700 W of power is supplied to the premises equipment 20 via the wiring L4 and the wiring L2. At this time, 1300 W of power that is insufficient in the premises equipment 20 is supplemented from the system power supply 10 and supplied to the premises equipment 20 via the wiring L1 and the wiring L2.

  Next, when the load power of the premises equipment 20 is 3700 W, the 3000 W power generated by the solar power generation device 2 is supplied to the premises equipment 20 via the wiring L3 and the wiring L2, and is generated by the fuel cell device 3. The 700 W of power thus supplied is supplied to the premises equipment 20 via the wiring L4 and the wiring L2. At this time, since there is no excess or deficiency in the premises equipment 20, power is not supplied from the system power supply 10 to the premises equipment 20.

  Finally, when the load power of the premises equipment 20 is 2000 W, 2000 W of the 3000 W power generated by the photovoltaic power generation apparatus 2 is supplied to the premises equipment 20 via the wiring L3 and the wiring L2, and the rest The 1000 W of electric power is supplied as surplus power to the system power supply 10 via the wiring L3 and the wiring L1. At this time, the reverse flow is detected by the current sensor 9. Therefore, the electric power supplied from the fuel cell device 3 to the distribution board 4 side is reduced to zero, for example, by stopping the operation of the fuel cell device 3 by the reverse power relay of the fuel cell device 3. The operation of the fuel cell device 3 may be continued and the power to be reduced may be consumed to heat the water in the hot water storage unit provided in the fuel cell device 3.

  As can be seen from the operation of the power supply system 1 described above, the distribution board 4 uses the power supply generated by the solar power generation device 2 to exceed the load power of the premises equipment 20 by using the surplus power that has been exceeded. 10 and the power supplied from the fuel cell device 3 to the premises equipment 20 is reduced. In addition, even if the electric power generated by the solar power generation device 2 is less than the load power of the premises equipment 20, the sum of the electric power generated by the solar power generation device 2 and the electric power generated by the fuel cell device 3 is If the load power of the facility 20 is exceeded, a reverse power flow is detected by the current sensor 9. In this case, the electric power supplied from the fuel cell device 3 to the distribution board 4 side is reduced so that excess or deficiency does not occur in the premises equipment 20.

  Next, the malfunction prevention processing of the power supply system 1 by the control unit 11 will be described with reference to FIG.

  First, the control unit 11 generates power (first power) E (PV) of the solar power generation device 2, power generation (second power) E (FC) of the fuel cell device 3, and load power of the premises equipment 20. E (L) is acquired by communication or the like (step S1). Subsequently, the control unit 11 determines whether or not the generated power E (PV) of the solar power generation device 2 is equal to or greater than the load power E (L) of the premises equipment 20 (step S2).

  As a result of the determination, if the generated power E (PV) of the solar power generation device 2 is equal to or greater than the load power E (L) of the premises equipment 20, the control unit 11 issues a stop instruction for the fuel cell device 3. Then, the operation of the fuel cell device 3 is stopped (step S3). On the other hand, when the generated power E (PV) of the solar power generation device 2 is less than the load power E (L) of the premises equipment 20, the control unit 11 generates the generated power E (PV) of the solar power generation device 2. And the sum of the generated power E (FC) of the fuel cell device 3 and the load power E (L) of the premises equipment 20 is determined (step S4).

  As a result of the determination, when the sum of the generated power E (PV) of the solar power generation device 2 and the generated power E (FC) of the fuel cell device 3 is equal to or greater than the load power E (L) of the premises equipment 20 The control unit 11 issues a stop instruction for the fuel cell device 3 to stop the operation of the fuel cell device 3 (step S3). On the other hand, when the sum of the generated power E (PV) of the solar power generation device 2 and the generated power E (FC) of the fuel cell device 3 is less than the load power E (L) of the premises equipment 20, the control unit 11 performs the process after step S1 again.

  As described above, in the power supply system 1, the generated power of the photovoltaic power generation apparatus 2 exceeds the load power of the premises equipment 20 due to some troubles occurring in the distribution board 4. Even if the supply of the generated power from the fuel cell device 3 to the premises equipment 20 is continued as it is (that is, the power is not reduced), the generated power of the solar power generation device 2 is converted into the premises equipment by the control unit 11. When the load power is greater than 20, the operation of the fuel cell device 3 is stopped. Therefore, according to the power supply system 1, it is possible to prevent the operation of the power supply system 1 from being continued in a state where some trouble or the like has occurred in the distribution board 4.

  Furthermore, the control unit 11 stops the operation of the fuel cell device 3 when the sum of the generated power of the solar power generation device 2 and the generated power of the fuel cell device 3 is larger than the load power of the premises equipment 20. If no trouble or the like occurs in the distribution board 4, the fuel is generated even though the sum of the generated power of the photovoltaic power generation device 2 and the generated power of the fuel cell device 3 exceeds the load power of the premises equipment 20. It is not assumed that the supply of generated power from the battery device 3 to the premises equipment 20 is continued as it is (that is, the power is not reduced). Therefore, according to the power supply system 1, it is possible to more reliably prevent the operation of the power supply system 1 from being continued in a state where some sort of malfunction or the like has occurred in the distribution board 4.

  For example, as shown in FIG. 3, when an incorrect wiring occurs in the distribution board 4, the power supply system 1 prevents the power supply system 1 from continuing to operate in the state of the incorrect wiring. In FIG. 3, the wiring L2 for electrically connecting the distribution board 4 and the premises equipment 20 is not connected to the wirings L1, L3, L4 at the connection point P1, and is a fuel cell than the connection point P1. The connection point P2 located on the device 3 side is connected to the wiring L4. The current sensor 9 is provided on the wiring L4 between the connection point P1 and the connection point P2.

  If such a miswiring occurs in the distribution board 4, even if the generated power of the photovoltaic power generation device 2 exceeds the load power of the premises equipment 20, no reverse power flow is detected in the wiring L1, so the fuel cell device The supply of generated power from 3 to the premises equipment 20 is continued as it is (that is, the power is not reduced). Further, even if the sum of the generated power of the solar power generation device 2 and the generated power of the fuel cell device 3 exceeds the load power of the campus facility 20, the generated power of the fuel cell device 3 exceeds the load power of the campus facility 20. Unless a reverse power flow is detected in the wiring L1, the supply of generated power from the fuel cell device 3 to the premises equipment 20 is continued as it is (that is, the power is not reduced).

  The control unit 11 described above reliably prevents the operation of the power supply system 1 from being continued in a state where such an erroneous wiring is generated in the distribution board 4. Incidentally, in the wiring of the distribution board 4 shown in FIG. 3, when the generated power of the fuel cell device 3 exceeds the load power of the premises equipment 20, the current sensor 9 causes the connection point P1 side to be connected to the connection point P1 side. A current flowing through the wiring L4 is detected when power is supplied to. As a result, the power supplied from the fuel cell device 3 to the distribution board 4 side is reduced by the reverse power relay of the fuel cell device 3.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment. For example, the power supply system 1 may include a predetermined power generation device such as a gas engine power generation device instead of the fuel cell device 3. However, when the predetermined power generation device is the fuel cell device 3, the supply of generated power from the predetermined power generation device to the premises equipment 20 can be stably and efficiently performed.

  DESCRIPTION OF SYMBOLS 1 ... Power supply system, 2 ... Solar power generation device, 3 ... Fuel cell apparatus (predetermined power generation device), 4 ... Distribution board (circuit part), 10 ... System power supply, 11 ... Control part, 20 ... Premise equipment (electric power) Equipment to be supplied).

Claims (2)

A power supply system that supplies power through interconnection with a system power supply,
A solar power generation device for generating first power;
A predetermined power generation device for generating second power;
When the sum of the first power and the second power exceeds the load power of the power supply target facility, the surplus power is supplied to the system power supply, and the power is supplied from the predetermined power generator. A circuit unit for reducing the second power supplied to the supply target facility ;
If before Symbol first power is greater than or equal to the load power, the operation of the predetermined generator device is stopped, the first power in the case of less than the load power, the first power and the second when the sum of the power over the load power, and a control unit which Ru is stopped the operation of the predetermined generator device,
The control unit is configured to output the values of the first power, the second power, and the load power without passing through the circuit unit, the solar power generation device, the predetermined power generation device, and the power supply. power supply system, characterized that you get a communication from each of the relevant equipment. It said predetermined power generation apparatus, power supply system of claim 1, wherein it is a fuel cell system.

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