Distributed Power Systems

Abstract

To provide a distributed power supply system comprising a measurement device that performs a radio communication by a communication power generated by an electromagnetic induction power generation using a current flowing a wire of a measuring object, in which a communication failure of the measurement device is suppressed.SOLUTION: A distributed power supply system comprises: a dispersion type power source that supplies a power to a load via a main breaker; a measurement device that is arranged in a wire connected between a commercial power source and the main breaker, measures a measurement value related to the power transmitted in the wire, and transmits information on the measurement value by a radio communication with a communication power generated by an electromagnetic induction power generation using a current flowing in the wire; and a control part that controls an output of the dispersion type power source so that the current flows in the wire in the case where the measurement value in the information acquired from the measurement device by the radio communication is less than a predetermined reference measurement value or the case where the information cannot be acquired from the measurement device.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] In buildings that are equipped with so-called distributed power sources, such as cogeneration systems that generate electricity using fuel cells and use exhaust heat, in addition to commercial power sources, it is important to monitor overcurrents, reverse power flow, etc. For example, it has been common to monitor distributed power sources such as cogeneration systems by attaching a measuring device such as a clamp-type current sensor to the building's distribution board and connecting it to the control device of the distributed power source such as the cogeneration system via wiring work that penetrates the building's walls.

[0003] Incidentally, if it were possible to obtain data on a building's electricity usage directly from a smart meter using wireless communication technology, or indirectly from a home controller such as a HEMS (Home Energy Management System), it would be possible to eliminate the need to attach a clamp-type current sensor to a distribution board, etc. and to eliminate the need for wiring that penetrates the walls of the building; however, this has not yet been realized.

[0004] Furthermore, when using wireless communication technology for a measuring device such as a current sensor, it is necessary to supply the measuring device with the power required for wireless communication, but if a battery is used, the battery needs to be replaced, and wireless communication becomes impossible if the battery runs out. Therefore, the use of energy harvesting technology is being considered, which obtains the communication power required for wireless communication by electromagnetic induction power generation using the current flowing through the wiring of the measurement target (see Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5617103 Summary of the Invention [Problem to be solved by the invention]

[0006] Here, for example, a configuration is conceivable in which a measuring device is placed on the wiring between a main breaker to which a distributed power source is connected and a commercial power source, measurement value information (e.g., the amount of power) related to the power transmitted through the wiring is obtained from the measuring device, and the output of the distributed power source is controlled so that the power approaches 0 W. If the measuring device used is the aforementioned measuring device that obtains power for communication by electromagnetic induction generation using the current flowing through the wiring and performs wireless communication, if the power transmitted through the wiring on which the measuring device is placed remains at 0 W for a long period of time, it will be impossible to secure power for communication. As a result, it will become impossible to obtain measurement value information from the measuring device, and there is a possibility that it will become impossible to control the output of the distributed power source.

[0007] The present invention aims to suppress communication failures of a measuring device in a distributed power generation system that is equipped with a measuring device that performs wireless communication using communication power generated by electromagnetic induction power generation that utilizes the current flowing through the wiring to be measured. [Means for solving the problem]

[0008] The distributed power system of the first embodiment comprises a distributed power source that supplies power to a load via a main breaker, a measuring device that is placed on a wiring connected between a commercial power source and the main breaker and measures measurement values ​​related to the power transmitted through the wiring, and transmits information about the measurement values ​​via wireless communication using communication power generated by electromagnetic induction power generation that utilizes the current flowing through the wiring, and a control unit that controls the output of the distributed power source so that current flows through the wiring when a measurement value in the information obtained from the measuring device via the wireless communication is less than a predetermined reference measurement value or when the information cannot be obtained from the measuring device.

[0009] In this manner, in the configuration of the first aspect, when the measurement value in the information acquired from the measuring device via wireless communication is less than the predetermined reference measurement value, or when information cannot be acquired from the measuring device, the control unit controls the output of the distributed power source so that a current flows through the wiring, thereby ensuring power for communication, and thus preventing communication failures of the measuring device due to a lack of power for communication.

[0010] In the distributed power system of the second aspect, the control unit performs reduction control to reduce the output of the distributed power source when a measurement value in the information acquired from the measuring device via the wireless communication is less than a predetermined reference measurement value, or when the information cannot be acquired from the measuring device.

[0011] In this way, in the configuration of the second aspect, when the measurement value in the information acquired from the measuring device by wireless communication is less than a predetermined reference measurement value, or when information cannot be acquired from the measuring device, the control unit performs reduction control to reduce the output of the distributed power source, so that the power from the distributed power source becomes insufficient for the power used by the load. As a result, commercial power is transmitted from the commercial power source to the main breaker through the wiring. This makes it possible to secure power for communication, and to suppress communication failure of the measuring device due to a shortage of power for communication.

[0012] In a distributed power system of a third aspect, the measuring device is arranged on the wiring through which power from the distributed power source is transmitted from the main breaker to the commercial power source when the power from the distributed power source becomes excessive compared to the power used by the load, and the control unit performs an increase control to increase the output of the distributed power source when a measurement value in the information acquired from the measuring device via wireless communication is less than a predetermined reference measurement value or when the information cannot be acquired from the measuring device.

[0013] Thus, in the configuration of the third aspect, when the measurement value in the information acquired from the measuring device by wireless communication is less than the predetermined reference measurement value, or when information cannot be acquired from the measuring device, the control unit performs an increase control to increase the output of the distributed power source, resulting in a state in which the power from the distributed power source is excessive compared to the power used by the load. As a result, the power from the distributed power source is transmitted through the wiring from the main breaker to the commercial power source. This makes it possible to secure power for communication, and to suppress communication failures of the measuring device due to a shortage of power for communication. Effect of the Invention

[0014] Because of the above-mentioned configuration, the present invention has the excellent effect of suppressing communication failures of the measuring device in a distributed power supply system equipped with a measuring device that performs wireless communication using communication power generated by electromagnetic induction power generation that utilizes the current flowing through the wiring to be measured. [Brief description of the drawings]

[0015] [Figure 1] 1 is a schematic diagram showing a power supply system according to a first embodiment. [Diagram 2] 1 is a block diagram showing an example of a distributed power supply system according to a first embodiment. [Diagram 3] 2 is a block diagram showing an example of a functional configuration of a processor of the control device according to the first embodiment. FIG. [Figure 4] 5 is a flowchart showing an example of the flow of a control process executed by the control device according to the first embodiment. [Diagram 5] 10 is a flowchart showing an example of the flow of a control process executed by a control device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.

[0017] First Embodiment (Power Supply System 10) The configuration of a power supply system 10 according to this embodiment will be described below. Fig. 1 is a schematic diagram showing the configuration of a power supply system 10 according to this embodiment.

[0018] The power supply system 10 is a system for supplying power to an electric device 14 as an example of a load. In this embodiment, the power supply system 10 is applied to a house 12, and supplies power to the electric device 14 installed in the house 12. Examples of the electric device 14 installed in the house 12 include lighting fixtures, air conditioners, refrigerators, televisions, washing machines, and other devices.

[0019] Note that the target to which the power supply system 10 is applied is not limited to the house 12, and may be, for example, buildings or facilities such as offices, stores, theaters, warehouses, factories, and hospitals. In addition, in the present embodiment, the electric device 14 is given as an example of a load, but the load may be any device that uses electric power, in other words, any device that consumes electric power. Also, the target to which the power supply system 10 supplies electric power may be a connection terminal (specifically, a socket or the like) to which a load such as the electric device 14 is connected.

[0020] Specifically, the power supply system 10 includes a distributed power supply system 50, an electric wire 18, an electric wire 19, and a distribution board 30. The distributed power supply system 50 is a system having a distributed power supply, and includes a cogeneration device 20 as an example of a distributed power supply, a measuring device 40, and a control device 60. Each part of the power supply system 10 will be described below.

[0021] (Cogeneration system 20) As described above, the cogeneration system 20 is an example of a distributed power source. A distributed power source is a power supply device that is provided separately from the commercial power source 16 and supplies power to the electrical equipment 14. A distributed power source is a power source whose output (i.e., the amount of power supplied to the electrical equipment 14) is controllable.

[0022] In this embodiment, the cogeneration system 20 is a household fuel cell cogeneration system, and is installed, for example, on the premises outside the house 12. The cogeneration system 20 supplies generated electric power to the electric appliances 14 via a main breaker 34 (to be described later) of a distribution board 30. Specifically, the cogeneration system 20 has, for example, a fuel cell unit 22, a hot water storage unit 24, and a heat source unit 26.

[0023] Each of the fuel cell unit 22, the hot water storage unit 24, and the heat source device 26 has a separate housing and is configured by the equipment provided in each housing. Note that the fuel cell unit 22, the hot water storage unit 24, and the heat source device 26 may be configured in a single housing.

[0024] Although not shown, the fuel cell unit 22 has a fuel processor, a stack, an inverter, and a heat recovery device. In the fuel cell unit 22, the fuel processor produces hydrogen from city gas, and in the stack, the hydrogen reacts with oxygen in the air to generate direct current electricity (hereinafter referred to as DC power) and heat. Furthermore, in the fuel cell unit 22, the inverter converts the DC power to alternating current electricity (hereinafter referred to as generated power). The heat recovery device of the fuel cell unit 22 recovers heat by heating water sent from the hot water storage unit 24 with the heat generated in the stack.

[0025] Although not shown, the hot water storage unit 24 has a storage tank. In the hot water storage unit 24, water obtained from the water supply is sent to a heat recovery device of the fuel cell unit 22, and the water heated by the heat recovery device (i.e., hot water) is stored in the storage tank.

[0026] The heat source device 26 further heats the hot water sent from the storage tank of the hot water storage unit 24 by burning city gas as necessary, and supplies the water to the house 12 .

[0027] In this embodiment, a cogeneration system 20 that is a power generation device using a fuel cell is used as an example of a distributed power source, but is not limited to this. Examples of distributed power sources include a power generation device that rotates an engine or a turbine by burning gas, a power generation device that uses solar power and wind power, and a storage battery, and various power supply devices can be used. In a power generation device that uses solar power and wind power, for example, the output of power to the electric device 14 is controlled by controlling a conversion device (specifically, a power conditioner) that converts the generated direct current power into alternating current power. In a storage battery, for example, power from the above-mentioned power generation device or a commercial power source is stored, and the output of power supplied to the electric device 14 is controlled.

[0028] (Electric wire 18, electric wire 19, and distribution board 30) The electric wire 18 is an electric wire for drawing commercial power from the commercial power source 16 to the distribution board 30. One end of the electric wire 18 is connected to the commercial power source 16, and the other end is connected to the distribution board 30. The other end of the electric wire 18 is specifically connected to a service breaker 32 of the distribution board 30, which will be described later. The electric wire 18 is specifically, for example, a single-phase three-wire electric wire, and has a neutral wire 18A and voltage wires 18B and 18C. In addition, in a configuration in which the distribution board 30 does not have a service breaker 32, which will be described later, the electric wire 18 is connected to a main breaker 34 of the distribution board 30, which will be described later. In addition, the electric wire 18 is not limited to a single-phase three-wire electric wire, and may be any electric wire that can transmit power.

[0029] The electric wire 19 is an electric wire for drawing the generated power generated by the cogeneration device 20 to the distribution board 30. One end of the electric wire 19 is connected to the cogeneration device 20, and the other end is connected to the distribution board 30. Specifically, one end of the electric wire 19 is connected to the fuel cell unit 22 of the cogeneration device 20. The other end of the electric wire 18 is specifically connected to a service breaker 32 (to be described later) of the distribution board 30. Therefore, in this embodiment, the electric wire 19 transmits the AC generated power converted from the DC power in the inverter of the fuel cell unit 22 to the service breaker 32 of the distribution board 30. Specifically, the electric wire 19 is a single-phase three-wire electric wire and has a neutral wire 19A and voltage wires 19B and 19C. Note that the electric wire 19 is not limited to a single-phase three-wire electric wire, and may be any electric wire capable of transmitting power.

[0030] The distribution board 30 has a service breaker 32, a main breaker 34, and a safety breaker 36, and a circuit 31 in which these breakers 32, 34, and 36 are arranged. The service breaker 32, the main breaker 34, and the safety breaker 36 are arranged in this order from the upstream side of the circuit 31 in the direction in which current flows.

[0031] Specifically, the circuit 31 is configured with a single-phase three-wire electric wire, and has a neutral wire 31A and voltage wires 31B and 31C. Furthermore, the circuit 31 has a connection part 33 that connects the service breaker 32 and the main breaker 34, and an extension part 35 that extends from the main breaker 34 to the safety breaker 36 side. The connection part 33 of the circuit 31 and the electric wire 18 are an example of wiring connected between the commercial power source 16 and the main breaker 34.

[0032] A plurality of wirings 37 are connected to the extension portion 35 of the circuit 31, branching out from the extension portion 35 and transmitting power to the electric device 14. That is, the wirings 37 can also be considered as branch circuits branching out from the extension portion 35. Each of the plurality of wirings 37 is composed of a pair of wirings (electric wires), and each of the pair of wirings is connected to either the neutral line 31A and any two of the voltage lines 31B, 31C in the extension portion 35. In the example shown in Fig. 1, one wiring 37 is connected to the neutral line 31A and the voltage line 31B, and another wiring 37 is connected to the neutral line 31A and the voltage line 31C.

[0033] The service breaker 32 is a circuit breaker for determining the contract capacity, and has a function of breaking the circuit 31 when power exceeding the contract capacity is supplied. Note that the service breaker 32 may not be provided in some cases.

[0034] The main breaker 34 functions as a leakage current breaker that cuts off the circuit 31 when a leakage current occurs in the electric device 14, etc. The safety breaker 36 is attached to each of the wiring 37, and is a breaker that cuts off the wiring 37 when it detects a short circuit caused by a failure of the electric device 14, etc., or when a certain amount of power usage is detected.

[0035] In this embodiment, commercial power from the commercial power source 16 and power generated by the cogeneration system 20 are sent to the distribution board 30 to be joined together and can be used as power for the electrical appliances 14 installed in the house 12. Here, when the output power from the cogeneration system 20 is insufficient for the power usage (power consumption) used in the electrical appliances 14, the commercial power is used to make up the shortage. In other words, when the generated power of the cogeneration system 20 is insufficient for the power usage of the electrical appliances 14, the commercial power is transmitted from the commercial power source 16 to the main breaker 34 via the electric wire 18 and the connection part 33 of the circuit 31.

[0036] On the other hand, when the power used by the electrical appliance 14 and the power generated by the cogeneration system 20 are balanced, commercial power is not used and no power is transmitted to the electric wire 18 and the connection part 33 of the circuit 31 .

[0037] Furthermore, when the power generated by the cogeneration system 20 is in excess of the power used in the electrical equipment 14, commercial power is not used, and the excess power may be transmitted from the main breaker 34 to the commercial power source 16 through the electric wire 18 and the connection part 33 of the circuit 31 (i.e., reverse power flow).

[0038] The circuit 31 is not limited to a single-phase three-wire type electric wire, and may be any circuit capable of transmitting electric power.

[0039] (Measuring device 40) The measuring device 40 is disposed upstream of the main breaker 34. Specifically, the measuring device 40 is disposed at the connection portion 33 of the circuit 31 of the distribution board 30. That is, the measuring device 40 is disposed between the service breaker 32 and the main breaker 34 in the circuit 31 of the distribution board 30. More specifically, the measuring device 40 is disposed at the neutral conductor 31A in the connection portion 33 of the circuit 31. Note that the measuring device 40 may be disposed on the voltage lines 31B, 31C in the connection portion 33 or on the electric wire 18, as long as it is possible to measure a measured value related to power between the main breaker 34 and the commercial power source 16.

[0040] The measuring device 40 is a device that measures measurement values ​​(specifically, at least one of the current value, voltage value, and power amount) related to the power (e.g., commercial power from the commercial power source 16) transmitted through the connection portion 33 of the circuit 31 of the distribution board 30.

[0041] Specifically, as shown in Fig. 2, the measuring device 40 has a measuring unit 42, an induction power generating unit 44, and a communication unit 46. Although not shown, the measuring unit 42 has, for example, an annular core surrounding the circuit 31 and a winding wound around the core, and measures a measurement value related to the power transmitted through the winding in proportion to the power transmitted through the circuit 31, thereby measuring a measurement value related to the power transmitted through the connection unit 33. In this way, the measuring unit 42 measures a measurement value correlated with the power transmitted through the connection unit 33, thereby measuring a measurement value related to the power transmitted through the connection unit 33. The measuring unit 42 is not limited to the above configuration, and may have any configuration that can measure a measurement value related to the power transmitted through the connection unit 33.

[0042] Induction power generation unit 44 generates communication power for wireless communication by electromagnetic induction power generation using the current flowing through circuit 31. Furthermore, communication unit 46 transmits information on the measurement value measured by measurement unit 42 (hereinafter referred to as measurement value information) to control device 60 by wireless communication using the communication power generated by induction power generation unit 44.

[0043] The measurement device 40 may be configured to constantly perform measurement by the measurement unit 42 and communication by the communication unit 46, or may be configured to periodically perform the measurement and communication at predetermined intervals.

[0044] (Control device 60) The control device 60 is an example of a control unit, and is a device that controls the operation of the cogeneration system 20. Specifically, it controls the output of the cogeneration system 20 (i.e., the amount of power supplied to the electrical appliances 14). Note that the control device 60 may function as a device that controls the amount of hot water supplied by the cogeneration system 20 and the amount of heat generated by the heat source unit 26 in addition to the amount of power supplied by the cogeneration system 20.

[0045] As shown in FIG. 2, the control device 60 is configured as a computer having a processor 61, a memory 62, a storage 63, and a communication interface 64.

[0046] The processor 61 is, for example, configured with a CPU (Central Processing Unit) which is a general-purpose processor. Note that an example of the processor may be a dedicated processor configured with a circuit designed specifically for executing a specific process.

[0047] The communication interface 64 is an interface (i.e., a communication unit) for communicating with other devices including the measurement device 40. In this embodiment, the communication interface 64 receives measurement value information transmitted from the measurement device 40 through a wireless communication function.

[0048] The storage 63 stores various programs including a control program 63A (see FIG. 3) and various data. Specifically, the storage 63 is realized by a recording device such as a hard disk drive (HDD), a solid state drive (SSD), or a flash memory.

[0049] The memory 62 is a working area for the processor 61 to execute various programs, and temporarily records various programs or various data when the processor 61 executes processing. The processor 61 reads various programs including the control program 63A from the storage 63 into the memory 62, and executes the programs using the memory 62 as a working area.

[0050] In the control device 60, the processor 61 executes the control program 63A to realize various functions. The following describes the functional configuration realized by the cooperation of the processor 61 as a hardware resource and the control program 63A as a software resource. Figure 3 is a block diagram showing the functional configuration of the processor 61.

[0051] As shown in FIG. 3, in the control device 60, the processor 61 executes a control program 63A to function as an acquisition unit 61A and an output control unit 61B.

[0052] The acquiring unit 61A acquires the measurement value information received by the communication interface 64 from the measuring device 40. If a communication error occurs in the measuring device 40, the acquiring unit 61A cannot acquire the measurement value information. A communication error in the measuring device 40 occurs, for example, when no current flows at the position where the measuring device 40 is arranged in the circuit 31 of the distribution board 30, and the communication power required for wireless communication of the measuring device 40 cannot be obtained.

[0053] The output control unit 61B controls the output of the cogeneration system 20 (i.e., the amount of power supplied to the electric device 14) based on the measurement value information acquired by the acquisition unit 61A. Specifically, the output control unit 61B performs feedback control to control the amount of power generated in the fuel cell unit 22 of the cogeneration system 20 so that the current value (an example of a measurement value) at the measurement position of the measurement device 40 approaches a predetermined reference current value (an example of a reference measurement value). As an example, the reference current value is set to a minimum current value required to obtain communication power necessary for wireless communication of the measurement device 40.

[0054] In this embodiment, the output control unit 61B executes reduction control on the cogeneration unit 20 to reduce the output of the cogeneration unit 20 when the current value in the measurement value information acquired by the acquisition unit 61A is less than the reference current value (including 0 A) or when the acquisition unit 61A is unable to acquire the measurement value information.

[0055] In the reduction control, the amount by which the output of the cogeneration system 20 is reduced needs only to be equal to or greater than the amount of power that can ensure the reference current value in the measuring device 40. For example, if the reference current value required for wireless communication of the measuring device 40 is 0.2 A, the reference current value is ensured by reducing the output of the cogeneration system 20 by 20 W.

[0056] Here, if the output of the cogeneration system 20 is reduced, the power generated by the cogeneration system 20 will be insufficient for the power used by the electrical equipment 14. This power shortage is supplied from the commercial power source 16 to the main breaker 34, causing a current to flow through the connection part 33 of the circuit 31 of the distribution board 30.

[0057] Therefore, in other words, when the current value in the measurement value information acquired by the acquisition unit 61A is less than the reference current value (including 0 A), or when the acquisition unit 61A cannot acquire the measurement value information, the output control unit 61B controls the output of the cogeneration device 20 so that current flows through the connection part 33 of the circuit 31 of the distribution board 30.

[0058] If, as a result of the output control unit 61B executing reduction control on the cogeneration device 20, the current value in the measurement value information acquired by the acquisition unit 61A is equal to or greater than the reference current value, that is, if the wireless communication of the measuring device 40 has returned to a normal state, it is determined that the communication error is due to insufficient power of the measuring device 40, and feedback control is performed again.

[0059] Note that, if the current value in the measurement value information acquired by the acquisition unit 61A is less than the reference current value (including 0 A) immediately after the reduction control is once executed on the cogeneration system 20, or if the acquisition unit 61A cannot acquire the measurement value information, the reduction control does not have to be executed. In other words, the output control unit 61B may wait for a predetermined time.

[0060] Furthermore, if there is a function for learning from previously acquired data, it may be possible to learn the frequency of implementation of the reduction control according to the season and time period.

[0061] After the measuring device 40 temporarily measures 0 A, a current equal to or greater than the reference current value may flow through the circuit 31, causing the measurement result of 0 A to be transmitted.

[0062] Furthermore, the measured value measured by the measuring device 40 may be a voltage value, an amount of power, or the like, and the control device 60 may control the output of the cogeneration system 20 based on a reference voltage value, a reference amount of power, or the like.

[0063] (Action according to this embodiment) Next, an example of the operation of this embodiment will be described.

[0064] This process is performed by the processor 61 reading and executing the control program 63A from the storage 63. As an example, this process is started when the processor 61 acquires an instruction to execute the power generation operation of the cogeneration system 20.

[0065] As shown in FIG. 4, processor 61 determines whether or not measurement value information has been acquired from measuring device 40 (step S102).

[0066] When the processor 61 determines that the measurement value information has been acquired from the measuring device 40 (step S102: YES), the processor 61 proceeds to step S104. On the other hand, when the processor 61 determines that the measurement value information has not been acquired from the measuring device 40 (step S102: NO), the processor 61 executes reduction control on the cogeneration device 20 to reduce the output of the cogeneration device 20 (step S106), and returns to step S102.

[0067] In step S104, the processor 61 determines whether or not the current value in the measurement value information acquired from the measurement device 40 is less than the reference current value (including 0 A). When the processor 61 determines that the current value is less than the reference current value (including 0 A) (step S104: YES), it executes reduction control on the cogeneration device 20 (step S106) and returns to step S102.

[0068] On the other hand, if the processor 61 determines that the current value is greater than or equal to the reference current value (step S104: NO), it performs feedback control to control the output of the cogeneration system 20 so that the current value at the measurement position of the measuring device 40 approaches the reference current value (step S108), and returns to step S102.

[0069] In the control process shown in FIG. 4, for example, when an instruction to stop the execution of the power generation operation of the cogeneration system 20 is acquired, the process ends regardless of which step is being executed.

[0070] As described above, in this embodiment, when the current value in the measurement value information acquired from the measuring device 40 by wireless communication is less than the predetermined reference current value, or when the measurement value information cannot be acquired from the measuring device 40, the control device 60 performs reduction control to reduce the output of the cogeneration device 20, so that the generated power becomes insufficient for the power consumption of the electrical appliances 14. As a result, commercial power is transmitted from the commercial power source 16 to the main breaker 34 via the electric wire 18 and the connection part 33 of the circuit 31. This makes it possible to secure the communication power of the measuring device 40, and to prevent communication failure of the measuring device 40 due to a shortage of communication power.

[0071] Furthermore, in this embodiment, the measuring device 40 transmits the measurement value information to the control device 60 by wireless communication, so there is no need to connect the measuring device 40 and the control device 60 by wires. As a result, after the measuring device 40 is attached to the distribution board 30, there is no need to perform wiring work that penetrates the wall of the house 12.

[0072] <Second embodiment> Next, a second embodiment will be described. In the second embodiment, only the control operation of the control device 60 (specifically, the output control unit 61B of the processor 61) is different from that of the first embodiment, so the different parts will be described. Note that parts having the same functions as those in the first embodiment are given the same reference numerals and the description will be omitted as appropriate.

[0073] The output control unit 61B controls the output of the cogeneration system 20 (i.e., the amount of power supplied to the electrical equipment 14) based on the measurement value information acquired by the acquisition unit 61A. Specifically, the output control unit 61B performs feedback control to control the amount of power generated in the fuel cell unit 22 of the cogeneration system 20 so that the current value (an example of a measurement value) at the measurement position of the measurement device 40 approaches a reference current value (an example of a reference measurement value).

[0074] In this embodiment, when the current value in the measurement value information acquired by the acquisition unit 61A is less than the reference current value (including 0 A), or when the acquisition unit 61A is unable to acquire the measurement value information, the output control unit 61B executes an increase control on the cogeneration unit 20 to increase the output of the cogeneration unit 20.

[0075] In the increase control, the amount of increase in the output of the cogeneration system 20 needs to be equal to or greater than the amount of power that can ensure the reference current value in the measuring device 40. For example, if the reference current value required for wireless communication of the measuring device 40 is 0.2 A, the reference current value is ensured by increasing the output of the cogeneration system 20 by 20 W.

[0076] Here, if the output of the cogeneration system 20 is increased, the power generated by the cogeneration system 20 will be in excess of the power used by the electrical equipment 14. This excess power will flow in reverse from the main breaker 34 to the commercial power source 16, causing a current to flow through the connection 33 of the circuit 31 in the distribution board 30.

[0077] Therefore, it can be said that the output control unit 61B controls the output of the cogeneration unit 20 so that current flows through the connection part 33 of the circuit 31 of the distribution board 30 when the current value in the measurement value information acquired by the acquisition unit 61A is less than the reference current value (including 0 A) or when the acquisition unit 61A is unable to acquire the measurement value information.

[0078] In the second embodiment, a reverse power flow from the main breaker 34 to the commercial power source 16 is permitted. Specifically, in the second embodiment, the power flowing reversely from the main breaker 34 to the commercial power source 16 is sold.

[0079] If, as a result of the output control unit 61B executing the increase control on the cogeneration device 20, the current value in the measurement value information acquired by the acquisition unit 61A is equal to or greater than the reference current value, that is, if the wireless communication of the measuring device 40 has returned to a normal state, it is determined that the communication error is due to insufficient power of the measuring device 40, and feedback control is performed again.

[0080] Note that if the current value in the measurement value information acquired by the acquisition unit 61A is less than the reference current value (including 0 A) immediately after the increase control is once executed on the cogeneration system 20, or if the acquisition unit 61A cannot acquire the measurement value information, the increase control does not have to be executed. In other words, the output control unit 61B may wait for a predetermined time.

[0081] In addition, if there is a function for learning from previously acquired data, it may be possible to learn the frequency of implementation of the increase control according to the season and time of day.

[0082] (Action according to this embodiment) Next, an example of the operation of this embodiment will be described.

[0083] This process is performed by the processor 61 reading and executing the control program 63A from the storage 63. As an example, this process is started when the processor 61 acquires an instruction to execute the power generation operation of the cogeneration system 20.

[0084] As shown in FIG. 5, processor 61 determines whether or not measurement value information has been acquired from measuring device 40 (step S202).

[0085] When the processor 61 determines that the measurement value information has been acquired from the measuring device 40 (step S202: YES), the processor 61 proceeds to step S204. On the other hand, when the processor 61 determines that the measurement value information has not been acquired from the measuring device 40 (step S202: NO), the processor 61 executes an increase control on the cogeneration device 20 to increase the output of the cogeneration device 20 (step S206), and returns to step S202.

[0086] In step S204, the processor 61 determines whether or not the current value in the measurement value information acquired from the measuring device 40 is less than the reference current value (including 0 A). When the processor 61 determines that the current value is less than the reference current value (including 0 A) (step S204: YES), it executes an increase control on the cogeneration device 20 (step S206) and returns to step S202.

[0087] On the other hand, if the processor 61 determines that the current value is greater than or equal to the reference current value (step S204: NO), it performs feedback control to control the output of the cogeneration system 20 so that the current value at the measurement position of the measuring device 40 approaches the reference current value (step S208), and returns to step S202.

[0088] In the control process shown in FIG. 5, for example, when an instruction to stop the execution of the power generation operation of the cogeneration system 20 is acquired, the process ends regardless of which step is being executed.

[0089] As described above, in this embodiment, when the current value in the measurement value information acquired from the measuring device 40 by wireless communication is less than the predetermined reference current value, or when the measurement value information cannot be acquired from the measuring device 40, the control device 60 performs increase control to increase the output of the cogeneration device 20, resulting in a state in which the generated power is excessive relative to the power used by the electrical appliances 14. As a result, the generated power of the cogeneration device 20 is transmitted from the main breaker 34 to the commercial power source 16 via the electric wire 18 and the connection part 33 of the circuit 31. This makes it possible to secure the communication power of the measuring device 40, and to prevent communication failure of the measuring device 40 due to a shortage of communication power.

[0090] Furthermore, in this embodiment, the measuring device 40 transmits the measurement value information to the control device 60 by wireless communication, so there is no need to connect the measuring device 40 and the control device 60 by wires. As a result, after the measuring device 40 is attached to the distribution board 30, there is no need to perform wiring work that penetrates the wall of the house 12. [Explanation of symbols]

[0091] 10. Power Supply System 12 Houses 14 Electrical equipment (example of load) 16 Commercial power supply 18 Electric wire (example of wiring) 18A neutral wire 18B Voltage line 19 Electric wire 19A neutral wire 19B Voltage line 20 Cogeneration equipment (an example of distributed power sources) 22 Fuel Cell Unit 24 Hot water storage unit 26 Heat source machine 30 Distribution Board 31 Circuit 31A Neutral wire 31B Voltage line 32 Service breaker 33 Connection part (example of wiring) 34 Main breaker 35 Extension 36 Safety Breaker 37 Wiring 40 Measuring Equipment 42 Measuring part 44 Induction Generator Unit 46 Communications Department 50 Distributed Power Systems 60 Control device (an example of a control unit) 61 processors 61A Acquisition Department 61B Output control section 62 Memory 63 Storage 63A Control Program 64 Communication Interface

Claims

1. A distributed power source that supplies power to a load via a main breaker; a measuring device that is disposed on a wiring connected between a commercial power source and the main breaker, measures a measurement value related to the power transmitted through the wiring, and transmits information about the measurement value by wireless communication using communication power generated by electromagnetic induction power generation using the current flowing through the wiring; a control unit that controls an output of the distributed power source so that a current flows through the wiring when a measurement value in the information acquired from the measurement device via the wireless communication is less than a predetermined reference measurement value or when the information cannot be acquired from the measurement device; A distributed power system comprising:

2. The control unit is When a measurement value in the information acquired from the measuring device via the wireless communication is less than a predetermined reference measurement value, or when the information cannot be acquired from the measuring device, a reduction control is performed to reduce the output of the distributed power source. The distributed power system of claim 1 .

3. The measuring device is a power supply circuit breaker for connecting the distributed power source to the commercial power source when the power from the distributed power source becomes excessive with respect to the power consumption of the load; The control unit is When a measurement value in the information acquired from the measuring device via the wireless communication is less than a predetermined reference measurement value, or when the information cannot be acquired from the measuring device, an increase control is performed to increase the output of the distributed power source. The distributed power system of claim 1 .

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