JP5865225B2 - Control system, control device, and control method - Google Patents

Description

  The present invention relates to a control system, a control device, and a control method in a consumer having a plurality of types of distributed power supplies.

  In recent years, for example, a solar cell unit, a fuel cell unit, a storage battery unit, and the like are known as distributed power sources provided to power consumers (for example, Patent Document 1).

  The solar cell unit is a power generation device that generates power in response to reception of sunlight. The fuel cell unit is a power generation device that generates power using fuel such as gas. The storage battery unit is a power storage device that stores electric power in the storage battery.

  For example, in the Japanese system, electric power generated by renewable energy can be sold to an electric power company that manages the grid. Since sunlight is one of the renewable energies, the power (output power) output from the solar cell unit can be sold to a power company that manages the grid. In other words, the output power from the solar cell unit is recognized as a reverse power flow to the system. On the other hand, with respect to the output power from the fuel cell unit and storage battery unit that do not use renewable energy, neither the sale of power to the power company nor the reverse power flow to the grid is allowed.

JP 2002-152976 A

  For example, in a consumer provided with a solar cell unit and a fuel cell unit and / or a storage battery unit, the output power from the fuel cell unit and / or the storage battery unit is supplied to a load when selling the output power of the solar cell unit. be able to. In other words, among the output power from the solar cell unit, the amount supplied to the load can be reduced to increase the amount of reverse power flow to the system, that is, the amount of power sold.

  However, using a combination of multiple types of distributed power sources to increase the ratio of the amount of power sold in the output power from the solar cell unit (so-called boosting of the amount of power sold) may not be permitted in contracts with power companies. is there.

  In addition, in the Japanese system, for customers with distributed power sources that do not use renewable energy, reverse power flow detection sensors are installed to prevent the output power from such distributed power sources from flowing back into the system. It is obliged to install in a predetermined position. However, for example, in a consumer provided with a solar cell unit and a fuel cell unit and / or a storage battery unit, a reverse power flow detection sensor for preventing a reverse flow of output power from the fuel cell unit and / or the storage battery unit is There is a case where it is installed at a position where the reverse power flow of the output power from the battery unit cannot be detected. In such a case, even if the output power from the fuel cell unit and / or the storage battery unit is supplied to the load, the output power from the solar cell unit can flow backward to the system. Therefore, when the increase in power sales is not permitted due to a contract with the power company, the reverse power flow from the solar cell unit and the reverse power flow from the fuel cell unit and / or storage battery unit Although it is necessary to install a reverse power flow detection sensor at a position where both of them can be detected, it is difficult to detect whether or not the reverse power flow detection sensor is properly installed.

  Although there are such circumstances peculiar to Japan, in other countries, it is required to determine whether or not the reverse power flow detection sensor is correctly attached at the intended position.

  Therefore, an object of the present invention is to provide a control system, a control device, and a control method capable of detecting that a reverse power flow detection sensor is installed at an inappropriate position and appropriately operating a plurality of types of distributed power sources. And

  The control system according to the first feature includes a main power line that connects a system and a load, and a first power line that branches from the main power line at a first branch point on the main power line. A first distributed power source connected; a second distributed power source connected to the main power line via a second power line that branches from the main power line at a second branch point on the main power line; A reverse power flow detection sensor provided on the system side from the second branch point on the main power line, and a control device for controlling the first distributed power source and the second distributed power source. The first branch point is located closer to the system than the second branch point. The first distributed power source is a distributed power source that uses renewable energy, and the second distributed power source is a distributed power source that does not use renewable energy. The reverse power flow detection sensor detects a direction in which power is transmitted in the main power line with the grid side being positive. When the output power from the first distributed power source is detected and the detection value of the reverse flow detection sensor is zero, the control device notifies the user of an error.

  In the first feature, the control device detects the output power from the first distributed power source, and when the detection value of the reverse power flow detection sensor is zero, the second distributed power source. Stop the power output from.

  In the first feature, the control device detects the output power from the first distributed power source, and when the detection value of the reverse power flow detection sensor is positive, the second distributed power source. Stop the power output from.

  In the first feature, when the control device does not detect the output power from the first distributed power source over a predetermined period, it notifies the user of an error.

  1st characteristic WHEREIN: The sensor provided on the said 1st electric power line is further provided, The said control apparatus detects the output electric power from a said 1st distributed power supply based on the detected value of the said sensor.

  In the first feature, the first distributed power source is a solar cell unit, and the second distributed power source is a storage battery unit or a fuel cell unit.

  The control device according to the second feature includes a first power source connected to the main power line via a first power line branched from the main power line at a first branch point on the main power line connecting the grid and the load. A distributed power source and a second distributed power source connected to the main power line via a second power line branching from the main power line at a second branch point on the main power line are controlled. The first distributed power source is a distributed power source that uses renewable energy, and the second distributed power source is a distributed power source that does not use renewable energy. The first branch point is located closer to the system than the second branch point. The control device is provided when the output power from the first distributed power source is detected, and is provided on the main power line from the second branch point on the system side, and the main system side is positive, When the detection value of the reverse power flow detection sensor that detects the direction in which power is transmitted in the power line is zero, an error notification is given to the user.

  The control method according to the third feature includes a first power source connected to the main power line via a first power line branched from the main power line at a first branch point on the main power line connecting the grid and the load. A second connected to the main power line via a distributed power source and a second power line branched from the main power line at a second branch point located on the load side of the main power line with respect to the first branch point. Control with distributed power supply. The first distributed power source is a distributed power source that uses renewable energy, and the second distributed power source is a distributed power source that does not use renewable energy. The control method includes the step of detecting output power from the first distributed power source, and the reverse power flow detection sensor provided on the system side from the second branch point on the main power line, with the system side being positive. Detecting the direction in which power is transmitted in the main power line, and detecting that there is output power from the first distributed power source, and the detection value of the reverse power flow detection sensor is zero Includes providing an error notification to the user.

  According to the present invention, it is possible to provide a control system, a control device, and a control method capable of appropriately operating a plurality of types of distributed power supplies.

FIG. 1 is a diagram illustrating an energy management system 1 according to the first embodiment. FIG. 2 is a diagram illustrating the control system 100 according to the first embodiment. FIG. 3 is a diagram illustrating the control system 100 according to the first embodiment. FIG. 4 is a diagram illustrating the EMS 200 according to the first embodiment. FIG. 5 is a flowchart showing the control method according to the first embodiment. FIG. 6 is a flowchart showing step S200 in the control method according to the first embodiment. FIG. 7 is a flowchart showing step S300 in the control method according to the first embodiment. FIG. 8 is a flowchart showing step S400 in the control method according to the first embodiment.

  Hereinafter, a control system, a management device, and a control method according to an embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

  However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones. Therefore, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

[Outline of Embodiment]
The control system according to the embodiment is connected to the main power line via a main power line that connects a system and a load, and a first power line that branches from the main power line at a first branch point on the main power line. A first distributed power source, a second distributed power source connected to the main power line via a second power line branched from the main power line at a second branch point on the main power line, and the main power A reverse power flow detection sensor provided on the system side from the second branch point on the line, and a controller for controlling the first distributed power source and the second distributed power source. The first branch point is located closer to the system than the second branch point. The first distributed power source is a distributed power source that uses renewable energy, and the second distributed power source is a distributed power source that does not use renewable energy. The reverse power flow detection sensor detects a direction in which power is transmitted in the main power line with the grid side being positive. When the output power from the first distributed power source is detected and the detection value of the reverse flow detection sensor is zero, the control device notifies the user of an error.

  In the embodiment, the reverse power flow detection sensor is provided on the system side from the second branch point on the main power line, thereby preventing the reverse power flow of the output power from the second distributed power source. When the output power from the first distributed power source is detected and the detection value of the reverse power flow detection sensor is zero, the control device notifies the user of an error. Thereby, this invention can provide the control system, control apparatus, and control method which can operate | use a multiple types of distributed power supply appropriately.

[First Embodiment]
(Energy management system)
Hereinafter, the control system according to the first embodiment will be described. FIG. 1 is a diagram illustrating an energy management system 1 according to the first embodiment.

  As shown in FIG. 1, the energy management system 1 includes a customer 10, a CEMS 20, a substation 30, a smart server 40, and a power plant 50. The customer 10, the CEMS 20, the substation 30 and the smart server 40 are connected by a network 60.

  The consumer 10 includes, for example, a power generation device and a power storage device. The power generation device is a device that outputs electric power using fuel gas, such as a fuel cell. The power storage device is a device that stores electric power, such as a secondary battery.

  The consumer 10 may be a detached house or an apartment house such as a condominium. Alternatively, the customer 10 may be a store such as a convenience store or a supermarket, a commercial facility such as a building, or a factory.

  In the first embodiment, a customer group 10 </ b> A and a customer group 10 </ b> B are configured by a plurality of consumers 10. The consumer group 10A and the consumer group 10B are classified by, for example, a geographical area.

  The CEMS 20 controls interconnection between the plurality of consumers 10 and the power system. The CEMS 20 may be referred to as a CEMS (Cluster / Community Energy Management System) in order to manage a plurality of consumers 10. Specifically, the CEMS 20 disconnects between the plurality of consumers 10 and the power system at the time of a power failure or the like. On the other hand, the CEMS 20 interconnects the plurality of consumers 10 and the power system when power is restored.

  In the first embodiment, a CEMS 20A and a CEMS 20B are provided. For example, the CEMS 20A controls interconnection between the customer 10 included in the customer group 10A and the power system. For example, the CEMS 20B controls interconnection between the customer 10 included in the customer group 10B and the power system.

  The substation 30 supplies electric power to the plurality of consumers 10 via the distribution line 31. Specifically, the substation 30 steps down the voltage received from the power plant 50.

  In the first embodiment, a substation 30A and a substation 30B are provided. For example, the substation 30A supplies power to the consumers 10 included in the consumer group 10A via the distribution line 31A. For example, the substation 30B supplies power to the consumers 10 included in the consumer group 10B via the distribution line 31B.

  The smart server 40 manages a plurality of CEMSs 20 (here, CEMS 20A and CEMS 20B). The smart server 40 also manages a plurality of substations 30 (here, the substation 30A and the substation 30B). In other words, the smart server 40 comprehensively manages the customers 10 included in the customer group 10A and the customer group 10B. For example, the smart server 40 has a function of balancing the power to be supplied to the consumer group 10A and the power to be supplied to the consumer group 10B.

  The power plant 50 generates power using thermal power, sunlight, wind power, hydraulic power, nuclear power, or the like. The power plant 50 supplies power to the plurality of substations 30 (here, the substation 30A and the substation 30B) via the power transmission line 51.

  The network 60 is connected to each device via a signal line. The network 60 is, for example, the Internet, a wide area network, a narrow area network, a mobile phone network, or the like.

(Control system)
Hereinafter, the control system 100 according to the first embodiment will be described. FIG. 2 is a diagram illustrating details of the control system 100 according to the first embodiment.

  As shown in FIG. 2, the control system 100 includes a main power line 11, a distribution board 110, a load 120, a PV unit 130, a storage battery unit 140, a fuel cell unit 150, a hot water storage unit 160, and an EMS 200. Have The control system 100 is provided in the customer 10.

  In the first embodiment, each device is connected to the main power line 11 in the order of the PV unit 130, the storage battery unit 140, the fuel cell unit 150, and the load 120 as viewed from the order close to the system. However, the present invention can also be implemented when the connection between the storage battery unit 140 and the fuel cell unit 150 is reversed. Further, the PV unit 130, the storage battery unit 140, and the fuel cell unit 150 may be connected to each other via a signal line, and may transmit and receive various types of information such as output power. The signal line may be either wired or wireless.

  The main power line 11 is a power line connecting the system and the load 120. The PV unit 130 is connected to the main power line 11 via the power line 133 branched from the main power line 11 at the first branch point P1. The storage battery unit 140 is connected to the main power line 11 via the power line 143 branched from the main power line 11 at the second branch point P2. The fuel cell unit 150 is connected to the main power line 11 via the power line 153. In FIG. 2, the power line 153 branches from the power line 143, but may branch from the main power line 11. On the main power line 11, the first branch point P1 is located on the system side of the second branch point P2.

  The distribution board 110 houses a circuit breaker, a sensor, and the like provided on the power line. In FIG. 2, the first branch point P <b> 1 and the second branch point P <b> 2 on the main power line 11 are arranged in the distribution board 110.

  The load 120 is a device that consumes power supplied via the main power line 11. For example, the load includes devices such as a refrigerator, a freezer, lighting, and an air conditioner.

  The PV unit 130 is an example of a first distributed power source, and includes a PV 131 and a PCS 132. The PV unit 130 is an example of a power generation device, and is a solar power generation device that generates power in response to reception of sunlight. Sunlight is a renewable energy, and the output power from the PV unit 130 can be sold to a power company. The PV 131 outputs the generated DC power. The amount of power generated by the PV 131 changes according to the amount of solar radiation applied to the PV 131. The PCS 132 is a device (Power Conditioning System) that converts DC power output from the PV 131 into AC power. The PCS 132 outputs AC power to the main power line 11 via the power line 133.

  In the first embodiment, the PV unit 130 may have a pyranometer that measures the amount of solar radiation irradiated on the PV 131.

  In the first embodiment, the sensor CT1 is provided on the power line 133. The sensor CT1 is a current sensor, for example. Based on the detection value of the sensor CT1, the output power from the PV unit 130 is detected. The sensor CT1 is connected to the EMS 200 via a signal line, and transmits a detection value to the EMS 200. The sensor CT1 is connected to the PV unit 130, the storage battery unit 140, and the fuel cell unit 150 via signal lines, and transmits the detection value to these units. In FIG. 2, the sensor CT <b> 1 is arranged in the distribution board 110, but may be arranged outside the distribution board 110.

  The PV unit 130 is controlled by an MPPT (Maximum Power Point Tracking) method. Specifically, the PV unit 130 optimizes the operating point (a point determined by the operating point voltage value and the power value, or a point determined by the operating point voltage value and the current value) of the PV 131.

  The storage battery unit 140 is an example of a second distributed power supply, and includes a storage battery 141 and a PCS 142. The storage battery 141 is an example of a power storage device that stores electric power. The PCS 142 is a device (Power Conditioning System) that converts AC power supplied from the distribution line 31 (system) via the power line 143 into DC power. Further, the PCS 142 converts the DC power output from the storage battery 141 into AC power, and outputs the AC power to the main power line 11 via the power line 143.

  The fuel cell unit 150 is an example of a second distributed power source, and includes a fuel cell 151 and a PCS 152. The fuel cell unit 150 is an example of a power generation device that outputs power using fuel such as gas. The PCS 152 is a device (Power Conditioning System) that converts DC power output from the fuel cell 151 into AC power. The PCS 152 outputs AC power to the main power line 11 via the power line 153.

  The hot water storage unit 160 (hot water storage device) is an example of a heat storage device that converts electric power into heat, accumulates the converted heat as hot water, and stores heat generated by a cogeneration device such as the fuel cell unit 150 as hot water. It is. Specifically, the hot water storage unit 160 has a hot water storage tank, and warms water supplied from the hot water storage tank by exhaust heat generated by the operation (power generation) of the fuel cell 151. Specifically, the hot water storage unit 160 warms the water supplied from the hot water storage tank and returns the warmed hot water to the hot water storage tank.

  The EMS 200 is an apparatus (Energy Management System) that controls the PV unit 130, the storage battery unit 140, the fuel cell unit 150, and the hot water storage unit 160. Specifically, the EMS 200 is connected to the PV unit 130, the storage battery unit 140, the fuel cell unit 150, and the hot water storage unit 160 via signal lines, and the PV unit 130, the storage battery unit 140, the fuel cell unit 150, and the hot water storage unit. 160 is controlled using a signal conforming to a protocol such as Echonet Lite or ZigBee (registered trademark).

  The EMS 200 is connected to various servers via the network 60. Various servers store, for example, information (hereinafter referred to as energy charge information) such as the unit price of power supplied from the grid, the unit price of power received from the grid, and the unit price of fuel gas.

  Or various servers store the information (henceforth energy consumption prediction information) for predicting the power consumption of the load 120, for example. The energy consumption prediction information may be generated based on, for example, the past power consumption actual value of the load 120. Alternatively, the energy consumption prediction information may be a model of power consumption of the load 120.

  Or various servers store the information (henceforth PV power generation amount prediction information) for predicting the power generation amount of PV131, for example. The PV power generation prediction information may be a predicted value of the amount of solar radiation irradiated on the PV 131. Alternatively, the PV power generation prediction information may be weather forecast, season, sunshine time, and the like.

(Reverse power flow detection sensor)
Hereinafter, the reverse power flow detection sensor according to the first embodiment will be described. As shown in FIG. 2, the reverse power flow detection sensor CT2 is provided on the main power line 11 on the system side from the second branch point P2. The reverse power flow detection sensor CT2 is connected to the EMS 200 via a signal line, and transmits a detection value to the EMS 200. The reverse power flow detection sensor CT2 is, for example, a current sensor. Based on the detection value of the reverse power flow detection sensor CT2, the direction of the electric power transmitted through the main power line 11 is detected with the grid side being positive. The reverse power flow detection sensor CT2 detects a reverse power flow to the system of output power from a distributed power source that does not use renewable energy, that is, the storage battery unit 140 and / or the fuel cell unit 150. In other words, the reverse power flow detection sensor for the storage battery unit 140 and the reverse power flow detection sensor for the fuel cell unit 150 may be used together, or provided with sensors having different performance in terms of accuracy if necessary. Also good. Even when configured by separate sensors, since the current direction itself is not different, it can be regarded as a single reverse power flow detection sensor CT2. In FIG. 2, the reverse power flow detection sensor CT <b> 2 is arranged in the distribution board 110, but may be arranged outside the distribution board 110.

  The reverse power flow detection sensor CT2 is installed at a predetermined position according to a contract with the electric power company. FIG. 2 shows the installation position of the reverse power flow detection sensor CT2 when the increase in the amount of power sold is not permitted due to the contract with the electric power company. FIG. 3 shows the installation position of the reverse power flow detection sensor CT2 in the case where the increase in the amount of power sales is permitted in the contract with the electric power company.

  When the increase in the amount of power sold is not permitted due to the contract with the electric power company, the reverse power flow detection sensor CT2 is on the system side from the first branch point P1 on the main power line 11, as shown in FIG. Is provided. In such a case, the reverse power flow detection sensor CT2 detects a reverse power flow of output power from any one of the PV unit 130, the storage battery unit 140, and the fuel cell unit 150.

  When the increase in the amount of power sold is permitted by a contract with the electric power company, the reverse power flow detection sensor CT2 is connected to the first branch point P1 and the second branch on the main power line 11, as shown in FIG. It is provided between the points P2 (that is, the storage battery unit 140 and the fuel cell unit 150 side from the branch point P1). In such a case, the reverse power flow detection sensor CT2 detects the reverse power flow to the system of the output power from the storage battery unit 140 and / or the fuel cell unit 150. Here, it should be noted that the reverse power flow detection sensor CT2 does not detect the reverse power flow of the output power from the PV unit 130.

(Configuration of EMS)
Hereinafter, the EMS according to the first embodiment will be described. FIG. 4 is a block diagram showing the EMS 200 according to the first embodiment.

  As illustrated in FIG. 4, the EMS 200 includes a communication unit 210, a storage unit 220, a control unit 230, and a display unit 240. The EMS 200 is an example of a control device.

  The communication unit 210 transmits / receives various signals to / from the connected device via a signal line. For example, the communication unit 210 may receive information indicating the power generation amount of the PV 131 from the PV unit 130. The communication unit 210 may receive information indicating the storage amount of the storage battery 141 from the storage battery unit 140. The communication unit 210 may receive information indicating the power generation amount of the fuel cell 151 from the fuel cell unit 150. The communication unit 210 may receive information indicating the amount of hot water stored in the hot water storage unit 160 from the hot water storage unit 160.

  In the first embodiment, the communication unit 210 receives the detection values of the sensor CT1 and the reverse power flow detection sensor CT2 from the sensor CT1 and the reverse power flow detection sensor CT2.

  In the first embodiment, the communication unit 210 may receive energy fee information, energy consumption prediction information, and PV power generation amount prediction information from various servers via the network 60. Alternatively, when a smart meter is provided on the main power line 11, the communication unit 210 may receive energy charge information from the smart meter. Moreover, the communication part 210 transmits the signal for controlling the PV unit 130, the storage battery unit 140, the fuel cell unit 150, and the hot water storage unit 160 to each apparatus, for example.

  The storage unit 220 stores information received by the communication unit 210. The storage unit 220 stores whether or not an increase in the amount of power sold is permitted under a contract with the power company (that is, whether the reverse power flow detection sensor CT2 is in the attachment position in FIG. 2 or FIG. 3). The storage unit 220 stores an error counter for the connected device. As will be described later, the error counter is a counter for measuring the duration of a state in which no current is detected between the PV units 130 even though the output power from the PV unit 130 is present ( (See FIG. 6). Alternatively, the error counter is a counter for measuring the duration of the state where there is no output power from the PV unit 130, as will be described later (see FIG. 8).

  The control unit 230 controls the load 120, the PV unit 130, the storage battery unit 140, the fuel cell unit 150, the hot water storage unit 160, and the display device 250 using signals that comply with a protocol such as Echonet Lite or ZigBee (registered trademark). To do.

  In the first embodiment, the control unit 230 detects the output power from the PV unit 130 based on the detection value of the sensor CT1. Further, the control unit 230 detects the direction in which power and power are transmitted between the first branch point P1 and the second branch point P2 on the main power line 11 based on the detection value of the reverse power flow detection sensor CT2. In addition, the control unit 230 is stored in the storage unit 220 when a state in which no current is detected between the PV unit 130 and the system is detected even though there is output power from the PV unit 130. Add the error counter. Alternatively, the control unit 230 adds an error counter stored in the storage unit 220 when a state in which there is no output power from the PV unit 130 is detected.

  The display unit 240 displays various information stored in the storage unit 220. In 1st Embodiment, the display part 240 displays an error notification, when the control part 230 detects an error about the apparatus connected to EMS200. The display unit 240 may include an operation unit such as a touch panel for a user to input various information.

(Control method)
Hereinafter, a control method according to the first embodiment will be described. 5 to 8 are flowcharts showing the control method according to the first embodiment. These flows are performed at a predetermined cycle, for example, once every 5 minutes.

  As shown in FIG. 5, in step S100, the EMS 200 determines whether or not the detection value of the sensor CT1 is positive. If the determination result is “YES”, that is, if the output power from the PV unit 130 is detected, the EMS 200 performs the process of step S110. If the determination result is “NO”, that is, if the output power from the PV unit 130 is not detected, the EMS 200 performs the process of step S400.

  In step S110, the EMS 200 determines whether or not the contract with the electric power company is a contract that is not permitted to increase the amount of power sold. When the determination result is “YES”, that is, when the increase in the amount of power sold is not permitted due to the contract with the electric power company, the EMS 200 performs the process of step S200. If the determination result is “NO”, that is, if the increase in the amount of power sold is permitted in the contract with the electric power company, the EMS 200 performs the process of step S300.

<With no increase in power sales>
FIG. 6 is a flowchart showing step S200 in the control method according to the first embodiment. Step S200 is a control flow in the case where the increase in the amount of power sales is not permitted due to the contract with the power company.

  Here, in the case of no increase in the amount of power sold, the reverse power flow detection sensor CT2 is installed on the main power line 11 closer to the system side than the first branch point P1, as shown in FIG. It should be noted that it should.

  First, the case where the reverse power flow detection sensor CT2 is attached as shown in FIG. 2 will be described as an example.

  As shown in FIG. 6, in step S210, the EMS 200 determines whether or not the detection value of the reverse power flow detection sensor CT2 is positive. The determination result is “YES”, that is, the case where there is output power from the PV unit 130 and the current flow to the system side is detected by the reverse flow detection sensor CT2. That is, when the determination result is “YES”, there is a reverse power flow (power sale) from the PV unit 130. Since FIG. 6 shows a case where no increase in the amount of power sold is allowed, output from the storage battery unit 140 and / or the fuel cell unit 150 in a state where there is a reverse power flow (power sales) is not allowed. Therefore, the EMS 200 performs the output stop process of the storage battery unit 140 and / or the fuel cell unit 150 (step S230).

  In step S210, when the determination result is “NO”, there is a case where there is output power from the PV unit 130 and the current flow to the system side is not detected by the reverse flow detection sensor CT2. In this case, the EMS 200 performs the process of step S220.

  In step S220, the EMS 200 determines whether or not the detection value of the reverse power flow detection sensor CT2 is negative. When the determination result is “YES”, that is, when a current in the direction from the system to the branch point P1 is detected (assuming that the reverse power flow detection sensor CT2 is correctly attached as shown in FIG. 2), it is a PV unit. This means that the output power from 130 is being supplied to the load, but the power that is still insufficient in the load is being purchased from the system. In this case, since there is no reverse power flow (power sale), output from the storage battery unit 140 and / or the fuel cell unit 150 is permitted. That is, the EMS 200 does not perform the output stop process of the storage battery unit 140 and / or the fuel cell unit 150 and ends the process.

  When the determination result is “NO” in step S220, that is, when the detection value of the reverse power flow detection sensor CT2 is zero, there is no output power from the PV unit 130 even though there is output power. This means that no current is detected. In this case, the EMS 200 performs the process of step S240. As described above, the state in which no current is detected between the PV unit 130 and the output power from the PV unit 130 is a state in which the reverse power flow detection sensor CT2 is disconnected or a failure occurs. It is highly possible that In rare cases, the output power from the PV unit 130, or in addition to this, when the output from the storage battery unit 140 and / or the fuel cell unit 150 and the power consumption at the load are balanced, There may be cases where power transfer is zero, but such cases are usually instantaneous and not continuous.

  Therefore, in step S240, the EMS 200 increments the error counter by 1 (adds 1). Next, in step S250, the EMS 200 determines whether or not the error counter exceeds a predetermined value. Thereby, EMS200 discriminate | determines whether the state from which the detection value of reverse power flow detection sensor CT2 becomes zero is instantaneous or continuous. If the determination result is “YES”, that is, it is determined that the state in which the detection value of the reverse power flow detection sensor CT2 is zero is continued, the EMS 200 performs the process of step S260. When the determination result is “NO”, that is, when it is determined that the state where the detection value of the reverse power flow detection sensor CT2 becomes zero is not continuous, the EMS 200 performs the output stop process of the storage battery unit 140 and / or the fuel cell unit 150. The process is terminated without performing At this time, the EMS 200 resets the error counter (to zero).

  In step S260, the EMS 200 notifies the user of an error. The error notification is, for example, when there is a possibility that the reverse power flow detection sensor CT2 is installed at an inappropriate position when the increase in power sales is not permitted due to a contract with the power company Display that there is a possibility. Thereby, the user can confirm the malfunction of the reverse power flow detection sensor CT2 (for example, whether or not the installation position is appropriate in the contract with the electric power company or whether or not there is a failure).

  Next, in step S270, the EMS 200 determines whether to stop the output of power from the storage battery unit 140 and the fuel cell unit 150. For example, when the determination in step S250 is “YES” (that is, when it is determined to be zero continuously for a predetermined number of times), the determination is “YES”. Alternatively, when the user confirms the malfunction of the reverse power flow detection sensor CT2 in response to the determination result of step S260, the determination is “YES”. When the determination result is “YES”, the EMS 200 performs output stop processing (step S280) of the storage battery unit 140 and the fuel cell unit 150. If the determination result is “NO”, that is, if no malfunction is confirmed in the reverse power flow detection sensor CT2, the EMS 200 ends the processing without performing the output stop processing of the storage battery unit 140 and / or the fuel cell unit 150.

  In the flowchart shown in FIG. 6, when there is a state in which no current is detected between the PV unit 130 and the system in which there is no output power from the PV unit 130, that is, When the error counter exceeds a predetermined value, the EMS 200 stops the output of the storage battery unit 140 and the fuel cell unit 150. However, the embodiment is not limited to this.

  For example, when a state in which no current is detected between the PV unit 130 and the grid is detected in the state where there is output power from the PV unit 130, the EMS 200 detects the storage battery unit 140 and the fuel cell unit 150. Stop output immediately. As a result, in the case where the increase in power sales is not permitted, if the reverse power flow detection sensor is attached at the wrong position as shown in FIG. 3, the outputs of the storage battery unit 140 and the fuel cell unit 150 are immediately It stops and the unauthorized increase in power sales is suppressed.

<In the case where there is an increase in power sales>
FIG. 7 is a flowchart showing step S300 in the control method according to the first embodiment. Step S300 is a control flow in the case where an increase in the amount of electric power sold is permitted under a contract with the electric power company.

  Here, when the amount of power sold is pushed up, as shown in FIG. 3, the reverse power flow detection sensor CT <b> 2 is between the first branch point P <b> 1 and the second branch point P <b> 2 in the main power line 11. It should be noted that it should be installed in

  First, the case where the reverse power flow detection sensor CT2 is attached as shown in FIG. 3 will be described as an example.

  As shown in FIG. 7, in step S310, the EMS 200 determines whether or not the detection value of the reverse power flow detection sensor CT2 is positive. When the determination result is “YES”, that is, when it is detected that the output power from the storage battery unit 140 and / or the fuel cell unit 150 is flowing backward, the EMS 200 stops the output of the storage battery unit 140 and the fuel cell unit 150. Processing (step S320) is performed. This prevents output power from the storage battery unit 140 and / or the fuel cell unit 150 from flowing backward to the system. When the determination result is “NO”, it is determined that the output power from the storage battery unit 140 and / or the fuel cell unit 150 is not reversely flowed and is supplied to the load 120. The process is terminated without performing the output stop process of the battery unit 150.

  It should be noted that when the reverse power flow detection sensor CT2 is mounted at an incorrect position as shown in FIG. 2, the amount of power sold is not pushed up, but an illegal act is not performed. Should.

<PV unit error control>
FIG. 8 is a flowchart showing step S400 in the control method according to the first embodiment. Step S400 is a control flow when the output power from the PV unit 130 is not detected.

  The customer 10 including the PV unit 130 is expected to output electric power from the PV unit 130 except during nighttime or rainy weather. Nevertheless, the fact that the output power from the PV unit 130 is not detected for a predetermined period means that the PV unit 130 may be abnormal, or the sensor CT1 may be disconnected or malfunctioned. There is sex. When an abnormality has occurred in the PV unit 130, it is necessary to stop the output of the PV unit 130.

  Therefore, as shown in FIG. 8, in step S410, the EMS 200 increments the error counter by 1 (adds 1).

  In step S420, the EMS 200 determines whether or not the error counter exceeds a predetermined value. Here, it should be noted that the error counter illustrated in FIG. 8 is different from the error counter illustrated in FIG. It should be noted that the predetermined value described in FIG. 8 is different from the predetermined value shown in FIG. For example, the error counter shown in FIG. 8 is a counter for maintaining a state in which there is no output power from the PV unit 130 for an abnormally long period. Therefore, the predetermined value described in FIG. A value larger than the predetermined value shown is set.

  Thereby, EMS200 discriminate | determines whether the state from which the detection value of sensor CT1 becomes zero is a temporary thing or a continuous thing. If the determination result is “YES”, that is, it is determined that the state in which the detection value of the sensor CT1 is zero is continued, the EMS 200 performs the process of step S430. If the determination result is “NO”, that is, it is determined that the state in which the detection value of the sensor CT1 is zero is not continuous, the EMS 200 ends the process without performing the output stop process of the PV unit 130. At this time, the EMS 200 resets the error counter.

  In step S430, the EMS 200 notifies the user of an error. The error notification displays, for example, that there is a possibility that an abnormality has occurred in the PV unit 130. As a result, the user can confirm the abnormality of the PV unit 130 and the malfunction of the sensor CT1 (for example, being disconnected or out of order).

  Next, in step S440, the EMS 200 determines whether or not to stop the output of power from the PV unit 130. For example, when the determination in step S420 is “YES” (that is, when the output power of the PV unit 130 is determined to be zero continuously for a predetermined number of times), the determination is “YES”. Alternatively, when the user confirms the abnormality of the PV unit 130 or the malfunction of the sensor CT1 in response to the determination result of step S420, the determination is “YES”. In this case, the EMS 200 performs an output stop process (step S450) of the PV unit 130. When the determination result is “NO”, that is, when the abnormality of the PV unit 130 or the malfunction of the sensor CT1 is not confirmed, the EMS 200 ends the process without performing the output stop process of the PV unit 130.

  As described above, in the first embodiment, the reverse power flow detection sensor CT2 is provided on the main power line 11 on the system side from the second branch point P2, so that the outputs from the storage battery unit 140 and the fuel cell unit 150 are output. Prevent reverse power flow. When the output power from the PV unit 130 is detected and the detection value of the reverse power flow detection sensor CT2 is zero, the EMS 200 notifies the user of an error. Here, the case where the detection value of the reverse flow detection sensor CT2 is zero can be considered as follows.

  First, in the case where the reverse power flow detection sensor CT2 is provided between the first branch point P1 and the second branch point P2, that is, in accordance with a contract with the electric power company, an increase in the amount of power sales is permitted. The case will be described. When the detection value of the reverse flow detection sensor CT2 is zero, the output power from the PV unit 130 is all reversely flowed to the system, and the output power from the storage battery unit 140 and / or the fuel cell unit 150 is within the customer 10 It is thought that it covers power consumption. That is, it is considered that the amount of power sold by the PV unit 130 is pushed up by the storage battery unit 140 and / or the fuel cell unit 150. Such distributed power supply operation is not a problem when it is permitted to increase the amount of power sold in a contract with a power company.

  Next, the case where the reverse power flow detection sensor CT2 is provided on the system side from the first branch point P1, that is, the case where the increase in the amount of power sales is not permitted due to the contract with the electric power company will be described. When the detection value of the reverse power flow detection sensor CT2 is zero, it is considered that all output power from the PV unit 130 is consumed in the customer 10 without being sold.

  If the output power from the PV unit 130 and the storage battery unit 140 and / or the fuel cell unit 150 does not satisfy the power consumption in the customer 10, power is supplied from the system, and the detection value of the reverse power flow detection sensor CT2 is negative. Become. On the contrary, if the output power from the PV unit 130 exceeds the power consumption in the customer 10, the surplus of the output power is reversely flowed into the system, and the detection value of the reverse flow detection sensor CT2 becomes positive. When the detection value of the reverse power flow detection sensor CT2 provided on the system side from the first branch point P1 becomes zero, the output power from the PV unit 130 matches the power consumption in the customer 10, Only when there is no shortage. Since the output power from the PV unit 130 and the power consumption in the customer 10 are constantly fluctuating, they are unlikely to match. For example, the same applies to the case where the fuel cell unit 150 is subjected to load following control.

  Therefore, when the reverse flow detection sensor CT2 is provided on the system side from the first branch point P1, the detection value of the reverse flow detection sensor CT2 is often either positive or negative, and the detection value is zero. There is little to be. That is, when the detection value of the reverse flow detection sensor CT2 becomes zero, the reverse flow detection sensor CT2 may be provided at a position that is not on the system side from the first branch point P1, that is, the reverse flow detection sensor There is a possibility that CT2 is installed between the first branch point P1 and the second branch point P2. In such a case, the output power from the PV unit 130 may flow backward to the grid, and the output power from the storage battery unit 140 and / or the fuel cell unit 150 may cover the power consumption of the load in the customer 10, In other words, there is a possibility that the amount of power sales has been pushed up.

  Therefore, in the first embodiment, when the output power from the PV unit 130 is detected and the detection value of the reverse flow detection sensor CT2 is zero, the EMS 200 notifies the user of an error. . As a result, the user may have installed the reverse power flow detection sensor CT2 at a position different from the position where the increase in the amount of power sold is not permitted due to the contract with the power company. I can recognize that.

  In the Japanese system, the unit price of power sold when the increase in power sales is not permitted is set higher than the unit price of power sold when the increase in power sales is permitted. Therefore, if the reverse power flow detection sensor CT2 is installed at an inappropriate position when the increase in power sales is not permitted, power can be sold at a unit price higher than a predetermined unit price. Would be disadvantageous to the user. For example, when installing a distributed power supply, it is conceivable that the installation position of the reverse power flow detection sensor CT2 is erroneously changed. Providing an error notification when the detection value of the reverse power flow detection sensor CT2 is zero can be a countermeasure against such a situation.

  In the first embodiment, the sensor CT1 is provided on the power line 133. The EMS 200 detects the output power from the PV unit 130 based on the detection value of the sensor CT1. When the sensor CT1 does not detect the output power from the PV unit 130 for a predetermined period, the EMS 200 notifies the user of an error. The customer 10 including the PV unit 130 is expected to output electric power from the PV unit 130 except during nighttime or rainy weather. Nevertheless, the fact that the output power from the PV unit 130 is not detected for a predetermined period of time may indicate that an abnormality has occurred in the PV unit 130. Alternatively, the sensor CT1 may be disconnected or broken. In the first embodiment, the sensor CT1 is provided on the power line 133, and by detecting the output power of the PV unit 130 based on the detection value of the sensor CT1, the abnormality of the PV unit 130 and the malfunction of the sensor CT1 are detected. When the abnormal state continues, the power output of the PV unit 130 can be stopped.

[Other Embodiments]
Although the present invention has been described with reference to the above-described embodiments, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  The EMS 200 may be a HEMS (Home Energy Management System), a SEMS (Store Energy Management System), a BEMS (Building Energy Management System), or an FEM. There may be.

  In the embodiment, the customer 10 includes a load 120, a PV unit 130, a storage battery unit 140, a fuel cell unit 150, and a hot water storage unit 160. However, the consumer 10 should just have the load 120, the PV unit 130, the storage battery unit 140, and / or the fuel cell unit 150 at least.

  In the embodiment, the EMS 200 has been described as controlling the PV unit 130, the storage battery unit 140, and the fuel cell unit 150 based on the detection values of the sensor CT1 and the reverse power flow detection sensor CT2. However, the PV unit 130, the storage battery unit 140, and the fuel cell unit 150 may be controlled by each PCS (PCS 132, PCS 142, and PCS 152). In such a case, the PV unit 130, the storage battery unit 140, and the fuel cell unit 150 control their outputs based on the detection values received by the PCS from the sensor CT1 and the reverse power flow detection sensor CT2. Alternatively, any of the PCS 132, PCS 142, and PCS 152 may control the outputs of the PV unit 130, the storage battery unit 140, and the fuel cell unit 150.

  In the embodiment, the storage battery 141 of the storage battery unit 140 has been described as storing power supplied from the system. However, for example, the power output from the PV unit 130 or the fuel cell unit 150 may be stored.

  The fuel cell 151 of the fuel cell unit 150 may be, for example, an SOFC or a PEFC.

  DESCRIPTION OF SYMBOLS 1 ... Energy management system, 10 ... Consumer, 11 ... Main power line, 20 ... CEMS, 30 ... Substation, 31 ... Distribution line, 40 ... Smart server, 50 ... Power plant, 51 ... Transmission line, 60 ... Network, 100 ... Control system, 110 ... Distribution board, 120 ... Load, 130 ... PV unit, 131 ... PV, 132 ... PCS, 133 ... Power line, 140 ... Storage battery unit, 141 ... Storage battery, 142 ... PCS, 143 ... Power line, 150 ... Fuel cell unit, 151 ... Fuel cell, 152 ... PCS, 153 ... Power line, 160 ... Hot water storage unit, 200 ... EMS, 210 ... Communication unit, 220 ... Storage unit, 230 ... Control unit, 24 ... Display unit, CT1 ... Sensor, CT2 ... Reverse power flow detection sensor

Claims (8)

A main power line connecting the grid and the load;
A first distributed power source connected to the main power line via a first power line branching from the main power line at a first branch point on the main power line;
A second distributed power source connected to the main power line via a second power line branching from the main power line at a second branch point on the main power line;
On the main power line, a reverse power flow detection sensor provided on the grid side from the second branch point;
A controller for controlling the first distributed power source and the second distributed power source,
The first branch point is located closer to the system than the second branch point,
The first distributed power source is a distributed power source that uses renewable energy, and the second distributed power source is a distributed power source that does not use renewable energy,
The reverse power flow detection sensor detects the direction in which power is transmitted in the main power line, with the grid side being positive,
When the output power from the first distributed power source is detected and the detection value of the reverse power flow detection sensor is zero, the control device performs error notification to the user. Control system. When the output power from the first distributed power source is detected and the detection value of the reverse power flow detection sensor is zero, the control device outputs the power from the second distributed power source. the control system of claim 1, wherein the stopping. When the output power from the first distributed power supply is detected and the detection value of the reverse power flow detection sensor is positive, the control device outputs the power from the second distributed power supply. the control system of claim 1, wherein the stopping.   2. The control system according to claim 1, wherein the control device notifies the user of an error when the output power from the first distributed power source is not detected over a predetermined period. A sensor provided on the first power line;
The control system according to claim 4, wherein the control device detects output power from the first distributed power source based on a detection value of the sensor.   The control system according to claim 1, wherein the first distributed power source is a solar cell unit, and the second distributed power source is a storage battery unit or a fuel cell unit. A first distributed power source connected to the main power line via a first power line branched from the main power line at a first branch point on the main power line connecting the grid and the load; A control device that controls a second distributed power source connected to the main power line via a second power line that branches from the main power line at two branch points;
The first distributed power source is a distributed power source that uses renewable energy, and the second distributed power source is a distributed power source that does not use renewable energy,
The first branch point is located closer to the system than the second branch point,
When the output power from the first distributed power source is detected, and on the main power line, provided on the system side from the second branch point, the power is supplied to the main power line with the system side being positive. A control device that performs error notification to a user when a detection value of a reverse flow detection sensor that detects a direction of transmission is zero. A first distributed power source connected to the main power line via a first power line branched from the main power line at a first branch point on the main power line connecting the grid and the load; and A control method for controlling a second distributed power source connected to the main power line via a second power line that branches from the main power line at a second branch point located on the load side of the first branch point. There,
The first distributed power source is a distributed power source that uses renewable energy, and the second distributed power source is a distributed power source that does not use renewable energy,
Detecting output power from the first distributed power source;
In the main power line, a reverse power flow detection sensor provided on the system side from the second branch point detects the direction in which power is transmitted in the main power line, with the system side being positive, and
When it is detected that there is output power from the first distributed power source, and the detection value of the reverse power flow detection sensor is zero, an error notification is provided to the user. Control method.

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