Power monitoring and control device

Abstract

To suppress wasteful gas consumption in an idling state, which is not reflected in household power consumption due to power generation.SOLUTION: In addition to the current power generation control, which sets the power generation of a cogeneration device 10 to an idling state when route B communication is not possible, when power information is acquired from a smart meter 36 through the B route communication at communication intervals at each fixed time (for example, 30 seconds), when the route B communication is not possible for a certain number of times (when communication is not possible for a longer period of time than a period used to determine the idling state), power generation is stopped. This makes it possible to reduce unnecessary gas consumption.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a power monitoring and control device that acquires power information such as current, power, and power amount required for operation control of distributed power generation facilities, for example, a household fuel cell cogeneration system. [Background technology]

[0002] In homes that are equipped with so-called distributed power sources, such as solar panels, storage batteries, or cogeneration systems that generate electricity using gas engines or fuel cells in addition to commercial power sources, and that also utilize exhaust heat, it is important to monitor overcurrents and reverse power flow.

[0003] In conventional home power generation systems, a CT (Current Transformer) clamp is attached to the distribution panel inside the home to acquire the home's power load and perform load following control (hereinafter referred to as the wired system).

[0004] On the other hand, there are wireless methods such as using wireless CTs or remotely obtaining the power load from power information in smart meters. Wired methods have the disadvantage of requiring CT wiring work and the cost of drilling holes in the exterior wall, so wireless methods are desired.

[0005] Methods for load following control without CT wiring include using wireless CTs and remotely obtaining the power load from power information from a smart electricity meter (Route B).

[0006] Smart meters have three communication routes for acquiring information: Route A, Route B, and Route C. Route A is the communication route connecting the smart meter with the electric power company, Route B is the communication route connecting the smart meter with HEMS, etc., and Route C is the communication route for the electric power company to provide data acquired via Route A to third parties (such as retail electricity suppliers).

[0007] Patent Document 1 describes the provision of a distribution board that can prevent the board from becoming large even when it accommodates devices that manage both power usage data for branch electric lines and power amount data from a smart meter.

[0008] In addition, in Patent Document 1, a power information transmission unit installed in a distribution board performs B-route communication with a smart meter using either G3PLC or Wi-SUN wireless communication, but the relationship between the power information transmission unit and the cogeneration equipment is not described.

[0009] Patent document 2 also describes that power information is obtained from a smart meter via the Route B communication path, and that it is possible to roughly track the ever-changing power usage in a home, thereby enabling control that approximates the power transition characteristics of a home.

[0010] However, the communication period in the cogeneration system may overlap with the communication period of other devices (A-route communication, B-route communication with other devices (HEMS, etc.), specific low-power radio of other devices, etc.), and communication may fail due to radio wave interference or communication standby control (carrier sense) to avoid radio wave interference.

[0011] If this communication failure occurs, it may not be possible to accurately control the amount of power generated, so the cogeneration system goes into a power generation idling state, stops the external output of power generation, and allows the power to be consumed by itself (for example, by the power source of a heater installed in the cogeneration system). During this time, power generation will not compensate for the household's power consumption, and the gas consumption for idling will be wasted energy.

[0012] As a reference document relating to the gas consumption due to idling, Patent Document 3 describes the monitoring control of minute leakage of a gas microcomputer meter attached to a gas pipe that is an energy source for generating electricity in a cogeneration system.

[0013] Specifically, if the cogeneration system operates continuously for 27 days (including the idling period mentioned above), a 24-hour (1-day) rest period is set up to prevent false detections due to the power generation function continuing to consume gas, and to recognize that there is no trace of leakage.If there is a trace of leakage, an alarm is issued. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-075895 [Patent Document 2] Japanese Patent Publication No. 2021-164198 [Patent Document 3] Japanese Patent Publication No. 2020-16344 Summary of the Invention [Problem to be solved by the invention]

[0015] However, since home power generation systems are basically operated continuously (including idling), gas is constantly being consumed, which can lead to reduced fuel efficiency.

[0016] An object of the present invention is to provide a power monitoring and control device that can suppress wasteful gas consumption during idling, which is not reflected in the household power consumption due to power generation. [Means for solving the problem]

[0017] The power monitoring and control device of the present invention is a power monitoring and control device that acquires information regarding power loads and controls load-following power generation by a distributed power generation facility that generates power using fuel gas, and includes: a communication unit that performs communication to acquire information regarding power consumption via wireless communication at each communication period of a fixed communication interval; and a power generation control unit that, if the period during which communication by the communication unit is not possible at each communication interval exceeds a predetermined first period, operates the distributed power generation facility in an idling state in which the power generation amount is less than or equal to the amount of power self-consumed by the distributed power generation facility; if the period during which communication is not possible exceeds a second period longer than the first period, stops power generation by the distributed power generation facility or reduces the power amount to less than that of the idling state; and resumes the load-following power generation of the distributed power generation facility when the wireless communication is restored.

[0018] According to the present invention, the communication unit executes communication for acquiring the information about power consumption via wireless communication at each communication time of a fixed communication interval.

[0019] The power generation control unit operates the distributed power generation equipment in an idling state in which the amount of power generated by the distributed power generation equipment is equal to or less than the amount of power self-consumed by the distributed power generation equipment when the period in which communication by the communication unit is not possible for each communication interval exceeds a predetermined first period, and stops power generation by the distributed power generation equipment or reduces the amount of power generated to a level less than that of the idling state when the period in which communication is not possible exceeds a second period that is longer than the first period.

[0020] Then, when wireless communication is restored, the distributed power generation facility resumes the load-following power generation, thereby reducing the wasteful consumption of fuel gas during idling, which is not reflected in the household power consumption due to power generation.

[0021] For example, one of the functions of a gas microcomputer meter is a leakage monitoring control unit that is reset every predetermined judgment period and, if it detects that the fuel gas has been continuously supplied during that judgment period, issues an alarm to alert the user to the possibility of a fuel gas leak.

[0022] In the present invention, the fuel gas is supplied via a gas microcomputer meter installed in a gas supply pipe, and when the power generation control unit determines that the third period until the leakage monitoring control unit of the gas microcomputer meter is reset is shorter than a predetermined period, even if the wireless communication is restored after the power generation is stopped or suppressed, it waits until the next reset time arrives in the leakage monitoring control unit and resumes the load-following power generation of the power generation unit.

[0023] In addition, in the present invention, the suppression of power generation is characterized by the amount of power generation at a gas consumption that is smaller than the gas consumption in the idling state and smaller than the fuel gas consumption at which leakage can be detected by the leakage monitoring control unit.

[0024] According to the present invention, if it is determined that the communication failure state of the power information request has continued for a long period of time, power generation is stopped, or the amount of power generation is reduced to a gas usage amount below the minimum flow count pulse of the gas microcomputer meter (no flow rate is detected).

[0025] The term "long period of time" refers to the period of time during which the engine continues to idle, resulting in a significant increase in fuel gas consumption compared to when the cogeneration system is not installed. By stopping or reducing power generation, it is possible to reduce wasteful consumption of fuel gas. [Effects of the Invention]

[0026] According to the present invention, it is possible to suppress the wasteful consumption of fuel gas during idling, which is not reflected in the household power consumption due to power generation. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a schematic diagram of a cogeneration system according to an embodiment of the present invention and a house in which the cogeneration system is installed. [Figure 2] FIG. 2 is a control block diagram of a controller of the cogeneration system according to the present embodiment. [Figure 3]FIG. 2 is a functional block diagram for communication interval adjustment control in the controller of the cogeneration system according to the present embodiment. [Figure 4] 4 is a flowchart showing a communication interval adjustment control routine executed by a controller of the cogeneration system according to the present embodiment. [Figure 5] 10 is a flowchart showing a power generation idling control routine executed for each B route communication. [Figure 6] 4 is a timing chart of the minute leakage monitoring control in the gas microcomputer meter. [Figure 7] 10 is a flowchart showing a communication interval adjustment control routine executed by a controller of a cogeneration system according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0028] FIG. 1 shows a schematic diagram of a household fuel cell cogeneration system (hereinafter, in this embodiment, simply referred to as "cogeneration system 10") as an example of a distributed power generation facility according to this embodiment.

[0029] The cogeneration system 10 is a system in which a tank unit and a fuel cell unit are installed side by side. Note that "side by side" does not necessarily mean that they are physically adjacent to each other, but rather that they are interconnected. In other words, the tank unit and the fuel cell unit may be installed separately and connected by piping, electrical wiring, etc.

[0030] The fuel cell unit takes in gas (for example, city gas 13A) from the gas supply pipe 50, refines the hydrogen, and generates electricity through a process centered on reforming the hydrogen with oxygen.

[0031] A gas microcomputer meter 52 is attached to the gas supply pipe 50. The downstream side of the gas microcomputer meter 52 is branched, one branch pipe is a pipeline that supplies gas to the fuel cell unit of the cogeneration system 10, and the other branch pipe is a pipeline that supplies gas to the gas equipment (stove, gas fan heater, etc.) of the house 12.

[0032] As shown in FIG. 1, the cogeneration system 10 is installed along the outer wall of a house 12, and workers go to the site to carry out the installation work.

[0033] FIG. 1 shows a state in which the installation work has been completed, the test run has been completed, and the system is ready for steady operation in cooperation with various facilities (electrical equipment, hot water supply facilities, etc.) in the house 12.

[0034] (Configuration of cogeneration system 10) Although not shown, the fuel cell unit of the cogeneration system 10 includes a hot module, a power conditioner, an exhaust heat recovery device, a heat storage tank, a radiator, a heat exchanger, etc., each of which is controlled in cooperation with each other by the controller 14 via a hot water supply-related control unit 27 and a power generation-related control unit 29 (both see Figure 2).

[0035] The hot module is a fuel processing device that receives gas (for example, city gas 13A) from a gas supply pipe 50, extracts hydrogen from the gas, supplies the extracted hydrogen to a fuel cell stack, and generates DC power using oxygen in the air.

[0036] The power conditioner converts the generated DC power into AC power and supplies it to the house.

[0037] The exhaust heat recovery device recovers heat from the exhaust gas generated by power generation.

[0038] The heat storage tank can store the heat recovered via the heat medium at a high temperature, and the stored heat is used to supply hot water.

[0039] The radiator dissipates heat and cools the heat transfer medium, but the radiator is not essential.

[0040] The heat exchanger uses the high-temperature heat medium from the heat medium tank to heat the tap water. The heat exchanger is not essential.

[0041] The cogeneration system 10 can also send the generated power to a heat source machine 16 via a power line 15. The heat source machine 16 further heats the hot water heated by the cogeneration system 10 by burning city gas (e.g., 13A) as needed and supplies the water to the house 12.

[0042] As shown in FIG. 2, the controller 14 includes a microcomputer 28 that is configured from a CPU 18, a RAM 20, a ROM 22, an I / O 24, and a bus 26 such as a data bus or a control bus that connects these components.

[0043] A hot water supply related control section 27 and a power generation related control section 29 are connected to the I / O 24, and operations relating to hot water supply and power generation are controlled by the controller 14.

[0044] In addition, a large-scale storage device 30 is connected to the I / O 24, which stores processing programs related to power generation and hot water supply executed by the controller 14, as well as historical information based on power generation (for example, in this embodiment, communication interval adjustment information, etc.).

[0045] Furthermore, a remote control 32 is connected to the I / O 24. The remote control 32 is installed inside the house 12 in which the cogeneration system 10 is to be installed, and has functions such as allowing a user to input commands regarding the cogeneration system 10 (and the heat source machine 16) and displaying the status of the cogeneration system 10.

[0046] As shown in FIG. 1, in the distributed power supply system according to this embodiment, power purchased from a commercial power supply 34 and power generated by a cogeneration system 10 are used as power sources for a house 12.

[0047] The commercial power supply 34 is connected to a smart meter 36. The smart meter 36 measures power information such as the current, power, and power consumption of the commercial power supply 34, and can transmit the measured information to a specific communication destination via communication paths A, B, and C.

[0048] That is, route A is a communication path connecting the smart meter 36 and the electric power company, route B is a communication path connecting the smart meter 36 and equipment installed in the house 12 (for example, the controller if a HEMS is installed), and route C is a communication path for providing data acquired by the electric power company via route A to a third party (such as a retail electricity supplier).

[0049] A power line 38 output from the smart meter 36 is wired to a distribution board 40 installed in the house 12 .

[0050] In the distribution board 40, if the smart meter 36 side is considered to be the upstream side, a service breaker 42, an earth leakage breaker 46, and a safety breaker 48 are installed in this order from the upstream side.

[0051] The service breaker 42 is a circuit breaker for determining the contract capacity, but may not be installed.

[0052] The earth leakage breaker 46 is a circuit breaker that quickly detects and cuts off leakage current in the internal wiring or electrical equipment of the house 12, thereby preventing electrical accidents.

[0053] The safety breaker 48 is attached to each branch circuit that transmits power from the distribution board 40 to each point of use in the house 12, and is a circuit breaker that automatically protects the circuit when it detects a short circuit caused by an electrical equipment failure or when power usage above a certain level is detected.

[0054] Here, the electricity generated by the cogeneration system 10 is merged with the commercial power source 34 via a dedicated safety breaker 48A installed in the distribution board 40, and can be used as a power source for electrical equipment inside the house 12.

[0055] Although not shown in the figure, the cogeneration system 10 is provided with a power line dedicated to use in the event of a power outage from the commercial power source 34, so that in a situation where power is not supplied from the commercial power source 34 due to a power outage, the power generated by the cogeneration system 10 can be supplied via a dedicated power outage outlet installed in part of the house 12.

[0056] Here, the controller 14 of the cogeneration system 10 needs to control the generated power in accordance with the amount of power used in the house 12, which varies from moment to moment.

[0057] In this embodiment, the communication interval for obtaining power information from the smart meter 36 via the communication path of Route B is set to once every 30 seconds as a standard. With this communication interval, it is possible to perform control (load following control) that generally follows the ever-changing power usage in the house 12 without violating various standards for wireless communication.

[0058] Incidentally, the smart meter 36 performs other communications such as communications via route A in addition to communications with the controller 14 of the cogeneration system 10 via route B. Also, there are periods when communications, including updates to the smart meter 36, are not possible.

[0059] Therefore, when the controller 14 of the cogeneration device 10 attempts to acquire power information via the communication path of Route B at a communication interval of once every 30 seconds, there is a possibility that communication to acquire power information may fail during periods when there is interference from communications from other devices in the home or neighboring homes (Route A, Route B, specific low-power radio).

[0060] In other words, the controller 14 of the cogeneration system 10 may not be able to obtain power information at the required frequency if the communication control is limited to obtaining the information at a communication interval of once every 30 seconds.

[0061] If the cogeneration system 10 continues to be unable to obtain power information at the required frequency, stable load following control will be impossible and the appropriate amount of power generation will not be maintained.Therefore, as a first measure, the system is put into an idling state in which the amount of power generation is kept within the amount consumed internally by the cogeneration system 10.

[0062] However, if the state in which power information cannot be obtained as frequently as necessary continues for a longer period of time, gas consumption will actually increase (for example, gas consumption will increase compared to when the cogeneration system 10 is not installed).

[0063] Therefore, in this embodiment, a threshold value is set for a period corresponding to the required frequency of power information (for example, the number of times acquisition fails), and if the threshold value is exceeded, power generation by the cogeneration system 10 is stopped.

[0064] 3 is a functional block diagram for communication interval control and power generation enable / disable control in the controller 14 of the cogeneration system 10. Each block in this functional block diagram is classified by function, and in this embodiment, the control is executed as software control operated by the CPU 18 based on a communication interval adjustment program stored in the ROM 22. Note that the operating programs shown in some or all of the functional blocks may be incorporated into an IC chip such as an ASIC and run on it.

[0065] 3, the wireless communication unit 54 establishes a communication protocol for acquiring power information via the communication path of Route B of the smart meter 36. The wireless communication unit 54 is connected to a communication interval timer 56, and receives the timing for establishing the communication protocol from the communication interval timer 56. In this embodiment, the communication protocol is established at a communication interval of once every 30 seconds as a default.

[0066] The wireless communication unit 54 is connected to the power information acquisition unit 58. When a communication protocol is established (successfully) in the wireless communication unit 54, the power information acquisition unit 58 acquires power information from the smart meter 36 via the communication path of Route B.

[0067] The power information acquisition unit 58 is connected to the system operation control unit 60 and notifies the system operation control unit 60 of the acquired power information.

[0068] The system operation control unit 60 calculates the power generation output and the like based on the acquired power information and sends control instruction signals to the necessary controlled devices of the cogeneration system 10. This allows the cogeneration system 10 to operate with a power generation output that roughly matches the power consumption in the house 12.

[0069] In addition to sending a control instruction signal to the control device to control the power generation output, the system operation control unit 60 may also send a control instruction signal to stop and restart power generation, which will be described later.

[0070] On the other hand, the wireless communication unit 54 is connected to a communication success / failure determination unit 62. The communication success / failure determination unit 62 determines whether the wireless communication unit 54 has succeeded in establishing a communication protocol at a predetermined communication interval, and sends the result to a consecutive failure counter 64.

[0071] The consecutive failure counter 64 counts up by +1 each time communication fails, and the cumulative failure count is reset when communication is successful. In other words, the count value of the consecutive failure counter 64 is the number of consecutive communication failures.

[0072] The consecutive failure counter 64 is connected to the determination unit 66, and the count value is sent to the determination unit 66 at each communication interval (every 30 seconds).

[0073] A failure count threshold value storage unit 68 is connected to the determination unit 66, and each time a count value is received from the successive failure counter 64, the count value is compared with a threshold value.

[0074] The judgment unit 66 is connected to the system operation control unit 60, and when the count value from the consecutive failure counter 64 is less than a threshold value, the judgment unit 66 outputs a power generation possible signal to the system operation control unit 60, and when the count value from the consecutive failure counter 64 is equal to or greater than the threshold value, the judgment unit 66 outputs a power generation impossible signal to the system operation control unit 60.

[0075] Based on the power generation feasibility information received from the judgment unit 66, the system operation control unit 60 determines whether to stop power generation while power generation is in progress, restart power generation while power generation is stopped, continue power generation, continue power generation stopped, etc., and sends a control instruction signal to the control device to stop power generation or restart power generation.

[0076] The operation of this embodiment will be described below with reference to the flowcharts of FIGS.

[0077] FIG. 4 is a flowchart showing a power information acquisition control routine executed by the controller 14 of the cogeneration system 10. As shown in FIG.

[0078] FIG. 5 is a flowchart showing an idling control routine for power generation that is executed for each B route communication.

[0079] In step 100, the power generation stop flag F is reset (0), and the process proceeds to step 102. This power generation stop flag F is reset (F=0) when power generation is possible, and is set (1) when power generation is not possible.

[0080] In step 102, the default value of the communication interval (in this embodiment, once every 30 seconds) is read, and the process proceeds to step 104.

[0081] In step 104, it is determined whether the communication interval has elapsed, and step 104 is repeated until the communication interval has elapsed. If the determination in step 104 is affirmative, the process proceeds to step 106, where it is determined whether communication via route B is possible.

[0082] If the determination in step 106 is affirmative, the process proceeds to step 108, where it is determined whether or not flag F is set (1). The case where the determination in step 108 is affirmative will be described later.

[0083] If the determination in step 108 is negative, power generation is possible, so the process proceeds to step 110, where the wireless communication unit 54 requests power information from the smart meter 36, and the process proceeds to step 112.

[0084] In step 112, it is determined whether or not the power information has been acquired in response to the request in step 110. If the determination in step 112 is negative, the power information could not be acquired, so the process proceeds to step 114, where error processing is performed (for example, a notification of failure to acquire power information, recording of log information, etc.), and the process returns to step 104, where the above process is repeated.

[0085] If the determination in step 112 is affirmative, the process proceeds to step 116, where the operating state of each control target device is controlled based on the power information, and the process returns to step 104, where the above process is repeated.

[0086] On the other hand, if the determination in step 106 is negative, it is determined that communication via route B is not possible, and the process proceeds to step 118 .

[0087] In step 118, it is determined whether flag F is set or not. If the determination is affirmative, it is determined that power generation has already been stopped, and the process returns to step 104.

[0088] If the determination in step 118 is negative, it is determined that power generation is currently in progress, and the process proceeds to step 120.

[0089] In step 120, it is recognized that this communication was not possible, and the process proceeds to step 122. In step 122, it is determined whether communication has been not possible for a certain number of times, and if the determination is negative, it is determined that it is too early to stop power generation, and the process returns to step 104.

[0090] Furthermore, if the determination in step 122 is affirmative, it is determined that further power generation may result in an increase in gas consumption, and the process proceeds to step 124, where an instruction is issued to execute a power generation stop process, and the process proceeds to step 126.

[0091] In step 126, a flag F indicating that power generation has stopped is set (1), and the process returns to step 104.

[0092] If this flag F is set (1), the determination at step 108 will be affirmative.

[0093] That is, after power generation is stopped, when B route communication becomes possible (positive determination) in step 106, a positive determination is made in step 108, the process proceeds to step 128, an instruction is given to execute the power generation startup process, and the process proceeds to step 130. In step 130, flag F, which indicates that power generation is possible, is reset (0), and the process proceeds to step 110.

[0094] FIG. 5 is a flowchart showing a power generation idling control routine executed for each B route communication.

[0095] In step 150, it is determined whether or not operation is stopped. If the determination in step 150 is affirmative, it is determined that power generation is stopped in the control of FIG. 4, and this routine ends.

[0096] If the determination in step 150 is negative, it is determined that the engine is in normal power generation or idling (both are generating power), and the process proceeds to step 152.

[0097] In step 152, the communication status of route B is confirmed, and then the process proceeds to step 154, where it is determined whether idling is necessary based on the communication status of route B.

[0098] If it is determined in step 154 ​​that idling is necessary, the process proceeds to step 156, where the system transitions to an idling state (if idling, the idling state is maintained), and this routine ends. If it is determined in step 154 ​​that idling is not necessary, the process proceeds to step 158, where the system transitions to normal power generation (if normal power generation is in progress, the normal power generation state is maintained), and this routine ends.

[0099] According to this embodiment, in addition to the current power generation control in which the power generation of the cogeneration device 10 is put into an idling state when communication via route B is not possible, when power information is obtained from the smart meter 36 via route B communication at a fixed communication interval (for example, 30 seconds), power generation is stopped when route B communication cannot be performed a fixed number of times (when communication is not possible for a longer period of time than the period when communication is judged to be in an idling state).

[0100] For example, in a comparative example, when B route communication is not possible for a certain number of times, the amount of power generated is reduced to an amount that can be consumed by internal equipment (e.g., a heater) in the cogeneration system 10, and power generation continues. However, if this period in which B route communication is not possible continues for a predetermined period (multiple communication opportunities), the amount of gas consumed may actually increase.

[0101] In contrast to this, in this embodiment, power generation is stopped when communication is disabled for multiple consecutive communication opportunities, thereby reducing unnecessary gas consumption.

[0102] (Variation) In this embodiment, a threshold value is set for a period corresponding to the required frequency of power information (for example, the number of times acquisition has failed), and if the threshold value is exceeded, the cogeneration system 10 is stopped.

[0103] Here, the cogeneration system 10 is forced to stop gas consumption (stop power generation) when the operation of the minute leakage monitoring function of the gas microcomputer meter 52 is avoided.

[0104] The gas microcomputer meter 52 has multiple functions to measure the flow rate of gas being supplied and to monitor abnormalities in the gas supply. In addition to the main monitoring functions (abnormal leakage monitoring function, earthquake detection function, pressure monitoring function, long-term use monitoring function), it also has a "micro leakage monitoring function" as a safety function, although it does not actively cut off the gas supply.

[0105] As shown in FIG. 6, the minute leakage monitoring function issues an alarm (such as blinking an alarm lamp) when leakage continues for a certain period of time (for example, 30 days) (see arrow A in FIG. 6).

[0106] In the cogeneration system 10, gas is normally consumed continuously for the purpose of generating electricity, and a certain period of time during which power generation is suspended is set before 30 days have passed so that the minute leakage monitoring function will not be activated. As an example, a 24-hour (third period) power generation suspension period is set once every 27 days of continuous operation, and the alarm counter of the safety function is reset (see arrow B in FIG. 6).

[0107] By setting a 24-hour (1-day) rest period after the cogeneration system 10 has been operating continuously for 27 days, if there is no trace leakage, false detection by the power generation function can be prevented and it can be confirmed that there is no trace leakage.

[0108] In the cogeneration system 10 of this embodiment, a threshold value is set for a period corresponding to the required frequency of power information (for example, the number of times acquisition fails), and if the threshold value is exceeded, power generation by the cogeneration system 10 is stopped (hereinafter referred to as "stop control when power information fails").

[0109] On the other hand, the cogeneration system 10 is designed to prevent false detection of minute leaks by providing a 24-hour (one-day) rest period after 27 days of continuous operation (referred to as "minute leak forensic control").

[0110] In a modification of this embodiment, attention is focused on the fact that power generation by the cogeneration system 10 is stopped under different conditions, and in the power information failure stop control, when power generation by the cogeneration system 10 is stopped, even if communication for acquiring power information is restored, power generation is not immediately resumed, but power generation is continued to be stopped until the next alarm counter is reset (maximum of 24 hours), thereby reducing the chance of power generation being stopped due to minute leakage monitoring control. Note that, if the reset state is monitored without waiting for maximum 24 hours, power generation may be resumed as soon as it is reset.

[0111] The operation of the modified example of this embodiment will be described below with reference to the flowchart of Fig. 7. Note that the same steps as those in the flowchart of Fig. 4, which shows the operation of this embodiment, are given the same step numbers, and the description of those processes will be omitted.

[0112] In a modified example, if it is determined that route B communication is possible (positive determination in step 106) and it is determined in step 108 that power generation is stopped (positive determination in step 108), the process proceeds to step 130 to obtain the reset time tr of the alarm counter for leakage monitoring control due to the stoppage of power generation, and then the process proceeds to step 132. The reset time tr may be set to 24 hours after the stoppage of power generation, or if it is possible to monitor the reset state of the alarm counter for trace leakage monitoring control, it may be determined whether it has been reset.

[0113] In step 132, it is determined whether the reset time tr has been reached, and if the determination is negative, step 132 is repeated.

[0114] If the determination in step 132 is affirmative, it is determined that the B route disconnection due to the power information failure stop control has been released and the alarm counter for the minute leakage monitoring control has been reset, and the process proceeds to step 128.

[0115] This allows the period during which power generation is stopped due to a communication outage on Route B, based on the power information failure stop control, to be used as a period during which power generation is stopped to reset the alarm counter, based on the minute leakage forensic control.

[0116] In this embodiment and the modified example, power generation is stopped if communication is not possible for a certain number of consecutive times during the communication interval, but power generation may be continued at an amount of power generation less than that during idling. In this case, as a response to the modified example, it is preferable to generate power in a state where the gas consumption rate is reduced to below the minimum pulse of the flow rate count of the gas microcomputer meter 52 for monitoring minute leaks (a state where no flow rate is detected).

[0117] In this embodiment (including the modified example), the device is in an idling state during the first period, and power generation is stopped (or after a trace leak is detected) during the second period. However, instead of performing the stepwise processing of the first and second periods, power generation may be stopped directly (or after a trace leak is detected) when communication becomes impossible for a predetermined period. [Explanation of symbols]

[0118] 10 Cogeneration equipment 12 Houses 14 Controller 15 Power line 16 Heat source machine 18 CPU 20 RAM 22 ROM 24 I / O 26 Bus 27 Hot water supply related control unit 28 Microcomputer 29 Power generation related control section 30 Mass storage 32 Remote Control 34 Commercial power supply 36 Smart Meters 38 Power line 40 Distribution board 42 Service breaker 46 Earth leakage breaker 48 Safety Breaker 48A safety breaker 50 Gas supply pipe 52 Gas microcomputer meter 54 Wireless Communication Unit (Communication Unit) 56 Communication interval timer (communication section) 58 Power information acquisition section 60 System operation control unit (power generation control unit) 62 Communication success / failure determination unit (power generation control unit) 64 Consecutive failure counter (power generation control unit) 66 Judgment unit (power generation control unit) 68 Failure count threshold memory unit (power generation control unit)

Claims

1. A power monitoring and control device that acquires information about a power load and controls load-following power generation by a distributed power generation facility that generates power using fuel gas, a communication unit that performs communication for acquiring information about power consumption via wireless communication at each communication time of a fixed communication interval; a power generation control unit that, when a period during which communication by the communication unit is unavailable for each communication interval exceeds a predetermined first period, operates the distributed power generation equipment in an idling state in which the amount of power generated by the distributed power generation equipment is equal to or less than the amount of power self-consumed by the distributed power generation equipment, and, when the period during which communication is unavailable exceeds a second period longer than the first period, stops power generation by the distributed power generation equipment or reduces the amount of power to a level lower than that in the idling state, and resumes the load-following power generation of the distributed power generation equipment when the wireless communication is restored; and The fuel gas is supplied via a gas microcomputer meter installed in a gas supply pipe, The power generation control unit If it is determined that the period until the leakage monitoring control unit of the gas microcomputer meter is reset is shorter than a predetermined period, Even if the wireless communication is restored after the power generation is stopped or suppressed, the leakage monitoring control unit waits until the next reset time arrives and resumes the load following power generation of the power generation unit. Power monitoring and control equipment.

2. 2. The power monitoring and control device according to claim 1, wherein the suppression of power generation is performed at a gas consumption rate that is smaller than the gas consumption rate in the idling state and smaller than the fuel gas consumption rate at which leakage can be detected by the leakage monitoring and control unit.

3. 3. The power monitoring and control device according to claim 1, wherein the power generation control unit has a function of setting or canceling the first period.

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