JP2009284590A - Power generation system - Google Patents

Power generation system Download PDF

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Publication number
JP2009284590A
JP2009284590A JP2008131903A JP2008131903A JP2009284590A JP 2009284590 A JP2009284590 A JP 2009284590A JP 2008131903 A JP2008131903 A JP 2008131903A JP 2008131903 A JP2008131903 A JP 2008131903A JP 2009284590 A JP2009284590 A JP 2009284590A
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Prior art keywords
power
state
system
unit
load
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Pending
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JP2008131903A
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Japanese (ja)
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Takeshi Tomio
剛至 富尾
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Osaka Gas Co Ltd
大阪瓦斯株式会社
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Priority to JP2008131903A priority Critical patent/JP2009284590A/en
Publication of JP2009284590A publication Critical patent/JP2009284590A/en
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B10/00Integration of renewable energy sources in buildings
    • Y02B10/10Photovoltaic [PV]
    • Y02B10/14PV hubs
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/50Photovoltaic [PV] energy
    • Y02E10/56Power conversion electric or electronic aspects
    • Y02E10/563Power conversion electric or electronic aspects for grid-connected applications

Abstract

PROBLEM TO BE SOLVED: To provide a power generation system capable of supplying power from a system as soon as possible with respect to a self-supporting load that can be used even during a self-sustaining operation after the system is restored.
SOLUTION: A generator 12 that generates power by receiving an external energy source; a first state in which power is supplied from a commercial power supply 60 to a power load 62; and no power is supplied from the commercial power supply 60. The connection switching unit 50 configured to be able to switch between the second state in which the power generated by the generator 12 is supplied, and the control unit 18 that performs switching control of the connection switching unit. When the power system that constitutes the commercial power supply 60 transitions from the power failure state to the energized state, when it is detected that the power state has been continued for a predetermined specified time or longer when it is possible to recognize that the system has recovered from the power outage state, Control for switching the switching unit 50 from the second state to the first state is performed.
[Selection] Figure 1

Description

  The present invention relates to a power generation system, and in particular, a first state in which a power generator is provided and power is supplied from at least a commercial power source to a predetermined power load, and from the commercial power source to the predetermined power load. The present invention relates to a power generation system configured to be switchable between a second state in which power is not supplied and power generated by the generator is supplied.

In recent years, a distributed energy system aimed at reducing CO 2 emissions and saving energy has been developed, and its practical application is also progressing. In the future, it is considered that the use of distributed power generation systems that generate power in the power consumption area will also increase in ordinary homes, apartment houses, offices, and the like. For example, a gas engine cogeneration system capable of cogeneration with heat and electric power has attracted attention in that it can improve the overall energy efficiency because it can effectively use not only electric power but also thermal energy generated during power generation at the same time. Then, a control method for effectively utilizing heat generated during power generation is being developed (see, for example, Patent Document 1 below).

JP 2007-240016 A

  Distributed power generation systems such as the gas engine cogeneration system as described above are assumed to supply power to the load by grid connection during power generation, while some loads are supplied during a power failure of the system. On the other hand, it is comprised so that electric power supply is possible only from a generator. Such a state where the generator is operated without being connected to the grid is called “self-sustaining operation”.

  When the system is interrupted and shifts to a self-sustaining operation state, power is supplied from the generator with a predetermined self-supporting rated output only to a predetermined load capable of supplying power even during self-sustaining operation. This is because, when configured to allow power supply from the generator to any load, there is a risk that the power cannot be completely covered only by the output from the generator. This is because power is supplied only to a relatively important load. That is, during a self-supporting operation, only a certain limited load (hereinafter referred to as “self-supporting load”) can be used, resulting in a situation where there are many loads that cannot be used. For this reason, for power consumers, there is a situation in which it is desired to receive power supply from the system side immediately after the power failure of the system is restored.

  On the other hand, when the power company detects that the grid has failed, the power company temporarily transmits power to each bank to determine the cause of the power failure, determines whether the bank is normal, and then switches the power transmission bank in sequence. (Accident section) Perform processing for identification. Then, when a section where an accident causing a power failure occurs is identified, normal power supply is performed to a bank that does not include the accident section. When normal power supply is performed from the grid, a power consumer who is in a state where power is supplied to the self-supporting load is in a state where power is supplied to all loads. Strictly speaking, power is supplied from the system to a load that is not supplied with power from the distributed power source during self-sustained operation, and power is supplied from the distributed power source to the self-supporting load. Thereafter, after the distributed power supply is stopped, power is supplied from the system to the self-supporting load, so that power is supplied from the system to all loads. After that, the distributed power source is operated again, and the grid connection with the grid side is performed.

  During self-sustained operation, power is supplied from the distributed power supply to the self-sustained load at a self-sustained rated output. Even after the system is restored, power is continuously supplied from the distributed power source to the self-sustained load until the connection is switched to the system side. Since the self-sustained operation is an operation for the purpose of supplying necessary power to an important load even in an emergency, its output is limited to the self-supported rated output. Therefore, it cannot cope with the rapid increase of the self-supporting load during the self-supporting operation. In addition, even though the power is restored, the power is still being supplied from the distributed power source to the self-sustained load only when the fuel gas is consumed during power generation as in the gas engine cogeneration system. In the case of a distributed power source, the energy source may be wasted. From this point of view, if the system recovers, there is a need to supply power from the system as soon as possible even for an independent load.

  In view of the above problems, the present invention provides a power generation system that enables power supply from a system as soon as possible with respect to a self-supporting load that can be used even during a self-sustained operation after the system is restored. Objective.

  In order to achieve the above object, a power generation system according to the present invention includes a generator that generates power by receiving supply of an energy source from the outside, a first state in which power is supplied from a commercial power source to a predetermined power load, A connection switching unit configured to be switchable between a second state in which power is not supplied from the commercial power supply to the predetermined power load and power generated by the generator is supplied; and switching between the connection switching units A controller that performs control, and the controller recognizes that the power system has returned from the power outage state after the power system constituting the commercial power source has shifted from the power outage state to the energized state. A first feature is that, when it is detected that the energized state continues for a predetermined predetermined time that is possible, the connection switching unit is controlled to switch from the second state to the first state.

  In general, there is a situation in which the system cannot be regarded as having been restored to the normal state immediately after the system connected to the load of the power consumer is energized. This is because temporary energization is performed for each bank to identify the cause of power outage (accident section), and until the accident section is identified, the system is connected to the load of the power consumer with temporary energization This is because it cannot be recognized that the power is completely restored. For this reason, if the power supply from the system is immediately switched to the predetermined power load (self-sustained load) immediately after confirming the power supply to the system, the power supply to the system may stop again. In this case, the power supply from the system is stopped with respect to the self-supporting load, and it becomes necessary to supply the power from the generator again.

  In a system including a generator capable of grid interconnection, from a state where power is not supplied from the system to the load and from the generator, power is supplied from the system to the load. When switching, the operation of the generator is stopped before or after connection switching. After that, if the self-sustained operation is performed again, power is supplied from the power generator to the self-supporting load after the power generator is started again. In other words, even though it was determined that the system was completely restored and the power supply source was switched from the generator side to the system side, the system was not completely restored. If it is necessary to supply power from the generator because the energized state is stopped, it is necessary to immediately operate the stopped generator again. In this way, frequent stop / operation control of the generator is forced, and as a result, there is a problem that the remaining power of the power source is lost and the start-up cannot be performed.

  According to the first characteristic configuration of the power generation system according to the present invention, by detecting that the energized state continues for the specified time, the system has completely returned from the power failure state to the normal power supply state. Can be recognized. For this reason, since it is very unlikely that the system will be immediately de-energized after that, the predetermined power load (self-supporting) can be obtained by switching the connection switching unit to the first state after recognizing such a state. It is possible to stably supply power to the load) from the system side. As a result, the state in which power is supplied from the generator to the self-sustained load is restored to the state in which power is supplied from the normal system to the self-supporting load as soon as possible after the power is restored. Can do. As a result, it is possible to cope with a sudden increase in self-sustained load, and it is also possible to avoid a situation in which the generator consumes an energy source more than necessary.

  Here, as the predetermined specified time, the time that must be waited before grid connection of distributed generation after grid energization, which is defined as grid interconnection technical requirements in the contracts of the power company, etc. (reconnection inhibition time) ) May be adopted. The reconnection prevention time is determined from the viewpoint of technical safety, and if the reconnection prevention time elapses after the energized state of the power failure system is confirmed, the system is normally energized. Since it can be confirmed that the state has been restored (power recovery), it can be considered that the electric power company guarantees that there is no problem on the grid side even if grid interconnection is performed thereafter. That is, after the energization state of the system is confirmed, after the reconnection prevention time has elapsed, switching to the first state and connecting the self-supporting load to the system side immediately stops the energization of the system immediately thereafter. The possibility that a situation will occur is extremely low, and it is possible to return to the state where power is supplied from the normal system to the self-supporting load as soon as possible after the system power is restored.

  In addition to the first characteristic configuration, the power generation system according to the present invention further includes a system energization detection unit that determines whether the power system is in a power outage state or an energization state, and the system energization detection unit includes the power system. The second feature is that a signal indicating the state change is transmitted to the control unit when the power supply state changes from the power failure state to the power supply state and when the power supply state changes from the power supply state to the power failure state.

  According to the second characteristic configuration of the power generation system according to the present invention, the control unit can automatically recognize the power supply / power failure state of the system. For this reason, the control unit obtains a signal indicating that the power system has changed from the power failure state to the energized state from the system energization detection unit, and then again receives a state change signal from the system energization detection unit until the predetermined specified time has elapsed. By performing control to switch the connection switching unit from the second state to the first state on the condition that the power supply is not acquired, the power supply from the normal system is performed to the self-sustained load as soon as possible after the system power is restored. It is possible to automatically return to the state that is displayed.

  In addition to the first or second characteristic configuration, the power generation system according to the present invention may further include the power system after the control unit switches the connection switching unit from the second state to the first state. The third feature is that control is performed to link the generator disconnected from the power grid to the power system.

  According to the third characteristic configuration of the power generation system according to the present invention, the connection switching unit is switched to the first state after detecting that the energized state continues for the predetermined period or longer. If it exists, it can be considered that the electric power system has recovered from the power failure state. For this reason, even if the control unit performs control for interconnecting the generators after the connection state of the connection switching unit is switched, there is no technical adverse effect on the system side. Thereby, after the power failure system recovers, it can be automatically returned to the grid connection state as soon as possible.

  According to the configuration of the present invention, it is possible to realize a power generation system that enables power supply from the system as early as possible with respect to a self-supporting load that can be used even during self-sustaining operation after the system is restored.

  Hereinafter, an embodiment of a power generation system according to the present invention (hereinafter referred to as “the present invention system” as appropriate) will be described with reference to the drawings.

  FIG. 1 is a block diagram showing a schematic configuration of the system of the present invention. FIG. 2 is a block diagram showing a system configuration relating to exhaust heat recovery, hot water supply, and heat supply to a heating load of the system 1 of the present invention.

  As shown in FIGS. 1 and 2, the system 1 of the present invention includes a power generation unit 10 that generates power by receiving fuel supply from the outside, a hot water supply load 70 that collects exhaust heat generated during operation of the power generation unit 10, and a heating terminal. The exhaust heat utilization hot water supply / heating unit 20 supplied to 71 is provided.

  As shown in FIG. 1, a power generation unit 10 includes a gas engine 11 that operates using city gas as a fuel, a generator 12 driven by the gas engine 11, and electric power generated by the generator 12 with an output voltage and frequency of a predetermined electrical system. A power converter 13 for converting the AC power into the AC power, a controller 18 for controlling the operation and output of the power generation unit 10, and a hot water supply / heating unit using exhaust heat by heating the cooling water by heat exchange with the exhaust heat of the gas engine 11. The heat exchanger 19 supplied to the 20 side is provided. The exhaust heat utilization hot water supply / heating unit 20 is provided with an exhaust heat utilization section 20a that utilizes the exhaust heat recovered by the heat exchanger 19, and the exhaust heat is disposed between the heat exchanger 19 and the exhaust heat utilization section 20a. A recovery coolant circulation pipe 22 and a circulation pump (electric coolant pump) 33 for circulating the coolant in the exhaust heat recovery coolant circulation pipe 22 are provided, and the exhaust heat recovered by the heat exchanger 19 is used as waste heat. It is the structure transmitted to the part 20a.

  The power conversion unit 13 includes a converter 14 that converts an AC voltage at the output end of the generator 12 into a DC voltage, and an inverter 15 that converts the DC voltage output from the converter 14 into an AC voltage and outputs the AC voltage. The converter 14 and the inverter 15 are both configured to be capable of voltage conversion in both directions.

  As shown in FIG. 2, the exhaust heat utilization hot water supply / heating unit 20 includes a hot water storage tank 21, an exhaust heat recovery coolant circulation pipe 22, a hot water circulation pipe 23, an exhaust heat recovery heat exchanger 24, a hot water supply output pipe 25, a heating system. An output circulation pipe 26, a heating heat exchanger 27, a water supply pipe 28, a heating terminal circulation pipe 29, a heating terminal branch pipe 30, an auxiliary heat source 31, and a control unit 32 are configured. Each pipe is provided with circulation pumps 33 to 35, an on-off valve 36, a three-way valve 37, a three-way valve 38, a check valve, a pressure adjusting valve, a temperature sensor, a pressure sensor, a flow meter, and the like as necessary. Has been.

  The hot water storage tank 21 is configured to store hot water heated by exhaust heat recovery of the power generation unit 10 so that the recovered exhaust heat can be stored. Further, hot water storage such as a temperature sensor or a water level sensor interposed therein is provided. A hot water storage amount can be detected by an amount detection means (not shown). Further, at the bottom of the hot water storage tank 21, when hot water is supplied from the hot water storage tank 21 to the hot water supply load 70, a water supply pipe 28 for replenishing the hot water storage tank 21 with water supply from a water supply source (not shown) such as a water supply or the like. It is connected.

  The exhaust heat recovery coolant circulation pipe 22 is a circulation circuit that constitutes an outward path and a return path that communicates between the heat exchanger 19 and the exhaust heat recovery heat exchanger 24 in the power generation unit 10. The exhaust heat recovery heat exchanger 24 exchanges heat between the jacket cooling water, which is the exhaust heat recovery coolant circulating in the exhaust heat recovery coolant circulation pipe 22, and the hot water circulating in the hot water circulation pipe 23. The exhaust heat recovery coolant circulation pipe 22 is connected to the primary side, and the hot water circulation pipe 23 is connected to the secondary side. The hot water circulation pipe 23 is a circulation circuit in which hot water taken out from the lower part of the hot water storage tank 21 is heated by the exhaust heat recovery heat exchanger 24 and returned to the upper part of the hot water storage tank 21 for circulation.

  With the above configuration, the jacket cooling water in the exhaust heat recovery coolant circulation pipe 22 is circulated by the circulation pump 33, and the hot water in the hot water circulation pipe 23 is circulated by the circulation pump 34. The exhaust heat in 10 is recovered and the cooling water is heated, and further, the heat of the cooling water heated in the exhaust heat recovery heat exchanger 24 is recovered and the hot water circulating in the hot water circulation pipe 23 is heated to store the hot water storage tank. 21 can be supplied. That is, the recovered exhaust heat of the power generation unit 10 is stored in the hot water storage tank 21.

  Further, the exhaust heat hot water supply / heating unit 20 is provided with an auxiliary heat source 31 such as a water heater using gas as fuel in the middle of the hot water circulation pipe 23, and the exhaust heat recovered from the power generation unit 10 has a shortage of heat. When doing so, it is possible to replenish the lack of heat.

  The hot water supply output pipe 25 is a pipe for supplying hot water to a hot water supply load 70 such as a bath tub or shower, a hot water tap in a kitchen or a washroom, etc., and mixed with water from the water supply downstream if necessary. Hot water is supplied.

  The heating output circulation pipe 26 is between an upper branch point near the upper part of the hot water storage tank 21 downstream of the hot water circulation pipe 23 and a lower branch point near the lower part of the hot water storage tank 21 upstream of the hot water circulation pipe 23. A circulation circuit in which two heat exchangers, a waste heat recovery heat exchanger 24 and a heating heat exchanger 27, are arranged on the way by a hot water circulation pipe 23 and a heating output circulation pipe 26 in a pipe connected via a heating heat exchanger 27. Is configured. The heating heat exchanger 27 is a heat exchanger that performs heat exchange between the hot water circulating in the heating output circulation pipe 26 and the heat medium (hot water) circulating in the heating terminal circulation pipe 29, and heating is performed on the primary side. The output circulation pipe 26 is connected, and the heating terminal circulation pipe 29 is connected to the secondary side. The heating terminal circulation pipe 29 is a circulation circuit that configures a forward path and a return path that communicate between the heating heat exchanger 27 and the heating terminals 71 such as a floor heating pipe and a bathroom heating dryer.

  With the above configuration, the hot water in the hot water circulation pipe 23 and the heating output circulation pipe 26 is circulated by the circulation pump 34, and the heat medium (warm water) in the heating terminal circulation pipe 29 is circulated by the circulation pump 35, thereby exhaust heat. The heating medium circulating in the heating terminal circulation pipe 29 can be heated and supplied to the heating terminal 71 in the heating heat exchanger 27 by the high temperature water heated by the recovered heat exchanger 24. That is, the recovered exhaust heat of the power generation unit 10 is consumed by the heating terminal 71 and effectively used.

  In addition, three-way valves 37 and 38 are provided in the forward path and the return path of the exhaust heat recovery coolant circulation pipe 22, and an open / close valve 36 is provided in the middle of the return path of the heating terminal circulation pipe 29 to branch the heating terminal. The piping 30 is arranged between the three-way valve 37 and the upstream side of the on-off valve 36, and between the three-way valve 38 and the downstream side of the on-off valve 36, respectively. As a result, it becomes possible to directly supply the cooling water heated by recovering exhaust heat in the heat exchanger 19 in the power generation unit 10 to the heating terminal circulation pipe 29 as a heat medium, so that the hot water circulation pipe 23 and the heating output circulation pipe 26 are supplied. The exhaust heat of the power generation unit 10 is recovered and can be supplied to the heating terminal 71 with higher efficiency than in the case of passing through.

  Returning to FIG. 1 again, the power generation unit 10 outputs a single-phase three-wire sine wave output of 100 V / 200 V for general household use. Further, the terminal 10a of the power generation unit 10 functions as an output terminal for generated power during the steady operation of the power generation unit 10, and as an input terminal for receiving the supply of power for starting the gas engine 11 from the outside when the unit 10 is started up. Function. When the power generation unit 10 is started, the generator 12 functions as a starter motor of the gas engine 11, and an AC voltage input from the outside is supplied to the generator 12 via the power conversion unit 13. The gas engine 11 is configured to start by the rotational movement.

  The control unit 18 is configured using a microcomputer or the like, and performs output control at the time of steady operation of the power generation unit 10, start control of the gas engine 11 at startup, and switching control of the connection switching unit 50. Moreover, it is comprised so that acquisition of the control signal from the control part 32 of the exhaust-heat utilization hot-water supply heating unit 20 is possible, and it is the structure which can control the gas engine 11 and the generator 12 based on this signal. A detailed description of the control unit 18 will be described later.

  The power generated by the power generation unit 10 is configured to be connected to the commercial power source 60 (single-phase three-wire system 100 V / 200 V) so as to supply power to the power loads 61 and 62. Specifically, the commercial power supply 60 and the power generation unit 10 are configured to be connected to each other via the first distribution board 40 and the second distribution board 41. The first distribution board 40 is connected to a power load 61 that cannot be used at the time of a power failure of the commercial power supply 60 (at the time of a system power failure), and the second distribution board 41 can be used even at the time of a system power failure. The power load 62 is connected. Moreover, the control part 32 of the electric power load 61 and the waste heat utilization hot water supply and heating unit 20 becomes the electric load at the time of the independent operation supplied with electric power by the independent operation of the power generation unit 10 at the time of a system power failure.

  In the first distribution board 40, a main breaker 42 and a breaker 43 are provided at both ends of a single-phase three-wire power line (1φ3W), and a plurality of branch breakers 44 and two current transformers 45 are provided in the middle. Yes. The commercial power source 60 is connected to the main breaker 42 side, the second distribution board 41 is connected to the breaker 43 side, and the power load 61 is connected to each branch breaker 44. The current transformer 45 detects a reverse power flow from the power generation unit 10 toward the commercial power supply 60 and a power failure of the system, and transmits a detection signal to the control unit 18. Furthermore, the current transformer 45 also transmits a signal to that effect to the control unit 18 even when the system is once energized after a power failure. In other words, the current transformer 45 also serves as a system energization detection unit that detects the energization / power failure state of the system. Hereinafter, when focusing on the function of detecting the energization / power failure state of the system, the current transformer 45 is appropriately referred to as “system energization detection unit 45”.

  The second distribution board 41 is provided with two switches 47 and 48 and a plurality of branch breakers 46. The switch 47 is an on / off switch (open / close switch). The primary side is connected to the breaker 43 of the first distribution board 40 via a single-phase three-wire power line (1φ3W), and the secondary side is a single-phase three-wire power line (1φ3W). ) To the terminal 10a used when the system of the power generation unit 10 is normal. The switch 48 is a two-input changeover switch, one input terminal is connected to the primary side of the switch 47 via a single-phase two-wire power line (1φ2W), and the other input terminal is a single-phase two-wire power line (1φ2W). Is connected to the terminal 10b used at the time of a system power failure of the power generation unit 10, and the output end is connected to each branch breaker 46 via a single-phase two-wire power line (1φ2W). The power generation unit 10 outputs a single-phase three-wire system 100V / 200V from the terminal 10a when the system is normal, and outputs a single-phase two-wire system 100V from the terminal 10b during a system power failure.

  The switches 51 and 52 for switching the connection between the terminals 10a and 10b, and the switches 47 and 48 are referred to as a connection switching unit 50. Each switch in the connection switching unit 50 is connected to the control unit 18 from the control unit 18. In this configuration, the switching control is performed in response to the control signal. The control unit 18 is configured by using a microcomputer or the like, and performs output control at the time of steady operation of the power generation unit 10, switching control of the connection switching unit 50 when the system is normal and during system power failure, starting control of the gas engine 11, and the like. I do.

  When the system is normal, the switch 47 is turned on (closed), and the commercial power supply 60 and the terminal 10a of the power generation unit 10 are connected and connected to the system. The switch 48 connects the load 62 side to the commercial power supply 60 side. The primary side, that is, the commercial power source 60 and the terminal 10 a of the power generation unit 10 are connected to the branch breaker 46. On the other hand, at the time of a system power failure, the switch 47 is turned off (opened) and the connection between the commercial power source 60 and the power generation unit 10 is cut off. The switch 48 connects the load 62 side to the power generation unit 10 side. The terminal 10b is connected to the branch breaker 46.

  The system 1 of the present invention further includes an operation switch 49 for forcibly operating the power generation unit 10 at the time of a system power failure. When the operation switch 49 is operated by the user, a forced operation signal is input from the operation switch 49 to the control unit 18 of the power generation unit 10, and the control unit 18 performs switching control of the connection switching unit 50 according to the forced operation signal. I do.

  Hereinafter, the control content of the control unit 18 will be described with reference to FIGS. 3 and 4. The control unit 18 performs switching control of the connection switching unit 50 as described above. FIG. 3 is a partially simplified view of the system of the present invention shown in FIG. FIG. 4 is a block diagram showing components for operating the switching control of the connection switching unit 50 among the functions of the control unit 18.

  As shown in FIG. 4, the control unit 18 includes a state signal input reception unit 90, a storage unit 91, a control content determination unit 92, and a control signal output unit 93.

  The state signal input receiving unit 90 receives a state signal indicating an energization / power failure state of a power system (hereinafter, referred to as “system 60” as appropriate) constituting the commercial power source 60. Specifically, when the system energization detection unit 45 detects the energization state of the system 60 and changes from the energization state to the power outage state, and when the power outage state changes to the energization state, the system energization detection unit 45 determines that the state The signal is transmitted to the control unit 18, and the state signal input receiving unit 90 of the control unit 18 acquires this signal. Then, the state signal input reception unit 90 transmits information related to the acquired state signal to the control content determination unit 92.

  Fig.3 (a) has shown the connection state of the connection switching part 50 in the case of grid connection. In FIG. 3A, both the load 61 and the load 62 (self-supporting load) are supplied with power from the system 60, and the generated power from the generator 12 is supplied to the system 60 via the switches 51 and 47. Are interconnected.

  The case where the system | strain 60 becomes a power failure from the state of Fig.3 (a) is demonstrated. At this time, since the current flowing through the bus connected to the system energization detection unit 45 from the system 60 side cannot be detected, the system energization detection unit 45 recognizes that the system 60 has changed from the energized state to the power failure state, and Information related to the change is transmitted to the control unit 18. Then, the state signal input receiving unit 90 of the control unit 18 acquires this signal and transmits information related to the acquired state signal to the control content determination unit 92.

  When the control content determination unit 92 acquires a signal from the state signal input reception unit 90, the control content determination unit 92 reads information related to switching control when the system 60 changes from the energized state to the power failure state from the storage unit 91, and the control signal output unit 93. To the connection switching unit 50.

  In the storage unit 91, information related to the control content to the connection switching unit 50 for each state and information related to a specified time described later are recorded. Since the system 60 has changed from the energized state to the power failure state, the control content determination unit 92 reads out information related to the switching control in the state from the storage unit 91. Specifically, after the generator 12 and the system 60 are disconnected, the switches 51 and 47 are opened and the switch 52 is connected to supply the generated power from the generator 12 to the self-supporting load 62. Information related to control contents for switching the switch 48 to the power generation unit 10 side is read. The information is output from the control signal output unit 93 to the connection switching unit 50.

  When the connection switching unit 50 acquires the information from the control unit 18, the connection switching unit 50 performs switching control based on the acquired information. As a result, the connection state shown in FIG. At this time, power is not supplied to the load 61, and power is supplied from the generator 12 to the load 62.

  Thereafter, when the system 60 changes from the power failure state to the energized state, the system energization detection unit 45 detects that the system 60 is in the energized state and transmits a signal to that effect to the control unit 18. The state signal input receiving unit 90 of the control unit 18 acquires this signal and transmits information indicating that the system 60 has changed from the power failure state to the energized state to the control content determination unit 92.

  The control content determination unit 92 reads information related to the specified time from the storage unit 91 and stands by for the specified time. When the state signal input receiving unit 90 does not newly acquire information on the state change from the system energization detection unit 45 until the specified time has elapsed, the system 60 is restored from the power failure state to the energized state. Judge. Then, the control content determination unit 92 reads information related to the switching control when the system 60 changes from the energized state to the power failure state from the storage unit 91 and outputs the information from the control signal output unit 93 to the connection switching unit 50. Specifically, by switching the switch 48 to the system 60 side and opening the switch 52, information on the control content indicating that the power supply source for the self-supporting load 62 is switched from the generator 12 to the system 60 is controlled by the control content determination unit 92. Is read from the storage unit 91 and the control signal output unit 93 outputs the information to the connection switching unit 50.

  When the connection switching unit 50 acquires the information from the control unit 18, the connection switching unit 50 performs switching control based on the acquired information. As a result, the connection state shown in FIG. At this time, power is supplied from the system 60 to both the loads 61 and 62. When the power supply source of the load 62 is switched to the grid 60 side, the generator 12 is stopped.

  On the other hand, when the state signal input reception unit 90 newly acquires information on the state change from the system energization detection unit 45 until the specified time elapses, the control content determination unit 92 re-enters the system energization detection unit. It waits until the information regarding the state change from 45 is acquired. The fact that the information related to the state change has been transmitted from the system energization detection unit 45 by the lapse of the specified time indicates that the system 60 is in a power outage state again. Therefore, in such a case, after the system 60 is energized again, the connection state at the time of power failure is continued until the energized state is confirmed for a specified time or longer.

  After the state shown in FIG. 3C is reached, the control unit 18 activates the generator 12 and then transmits a control signal for connecting the switches 51 and 47 to the connection switching unit 50. Thereby, the power generated by the generator 12 is grid-connected, and the state returns to the state of FIG.

  That is, in the system 1 of the present invention, it is confirmed that the system 60 is in the energized state after the system 60 is in a power failure state and the generated power from the generator 12 is supplied to the load 62. However, the electric power from the generator 12 is continuously supplied to the load 62 until it is confirmed that the energized state of the system 60 is maintained for a specified time. Then, when it is confirmed that the energized state of the system 60 is maintained for a specified time, it is recognized that the system 60 is completely restored, and the connection destination (power supply source) of the load 62 is set as the generator 12 side. Is switched to the grid 60 side.

  In general, there is a situation in which the system cannot be regarded as having been restored to the normal state immediately after the system connected to the load of the power consumer is energized. This is because temporary energization is performed for each bank to identify the cause of power outage (accident section), and until the accident section is identified, the system is connected to the load of the power consumer with temporary energization This is because it cannot be recognized that the power is completely restored.

  For this reason, if the power supply from the system 60 is immediately switched to the load 62 after confirming the power supply of the system 60 in a power failure state, the power supply of the system 60 may stop again. In this case, the supply of power from the system 60 to the load 62 is stopped, and it becomes necessary to supply power from the generator 12 again. As described above, when the connection destination for the load 62 is switched from the generator 12 to the grid 60 side, the generator 12 needs to be stopped. For this reason, after switching to the system 60 side once, when energization of the system 60 is stopped again in a short time, it is necessary to immediately operate the stopped generator 12.

  According to the system 1 of the present invention, after confirming energization of the system 60 in a power failure state, after confirming that this energization state is maintained for a predetermined specified time, the load 62 is switched to the system 60 side. In order to perform control, power is supplied to the load 62 from the system 60 that has been completely restored, and the possibility that the system 60 will be in a power outage again during a short time interval is extremely low. As a result, the generator 12 is not immediately forced to start the independent operation.

  Here, the predetermined specified time is a time that must be waited before grid connection of distributed power generation after system energization, which is stipulated as a grid connection technology requirement in the power company's contract etc. Time). This reconnection prevention time is determined from the viewpoint of technical safety, and if the reconnection prevention time elapses after the energized state of the power failure system is confirmed, the system is normal. Since it can be confirmed that the power supply has been restored (power recovery), it can be considered that the electric power company guarantees that there is no problem on the grid side even if grid interconnection is performed thereafter. That is, after the energization state of the system 60 is confirmed, after the reconnection prevention time has elapsed, the load 62 is switched to the system 60 side, and then the energization of the system 60 may immediately stop again. Therefore, it is possible to restore the load 62 to the state in which power is supplied from the normal system 60 instead of the generator 12 as soon as possible after the system 60 is restored.

  In addition, after confirming energization of the system 60 in a power failure state, the control content determination unit 92 has a counter function and a timer function capable of measuring time in order to determine whether or not this energization state lasts for a specified time. Good as you are doing.

  Further, in the above-described embodiment, after the control content determination unit 92 confirms the energization of the system 60 in the power failure state, the state signal input reception unit 90 newly receives information on the state change from the system energization detection unit 45. It is set as the structure which recognizes that the energization state of the system | strain 60 has continued for the regulation time by not acquiring. Instead, after the energization of the system 60 in a power failure state is confirmed, a signal for confirming the energization state of the system 60 is transmitted from the control unit 18 to the system energization detection unit 45 after the lapse of a specified time. The system energization detection unit 45 may transmit information regarding the energization state of the system 60 at that time to the control unit 18. In addition, when the system energization detection unit 45 detects that the system 60 has changed from a power failure state to an energized state, even if the energized state is maintained until the specified time has elapsed, after the specified time has elapsed. It is good also as a structure which transmits the signal which shows that the system | strain 60 is an electricity supply state to the control part 18 for confirmation.

  As described above, the system of the present invention is characterized in that the supply source for the self-supporting load 62 is switched to the system 60 side until it is detected that the power supply state has continued for a specified time after the system 60 has shifted from the power failure state to the power supply state. Instead, when the power is supplied from the generator 12 and it is confirmed that the energized state has continued for a specified time, the power is supplied from the grid 60 side to the self-supporting load 62. In the above embodiment, a system capable of cogeneration with heat has been described as an example. However, as long as the configuration has the above characteristics, the power generation system includes only the power generation unit 10 and does not include the waste heat utilization hot water supply / heating unit 20. Needless to say, this is feasible.

  Moreover, in the said embodiment, although the gas engine power generation system was mentioned as an example, the power generation method of the power generation unit 10 is not limited to the said embodiment. That is, the present invention can be applied to other power generation systems such as micro gas turbine power generation, fuel cells, and solar power generation. In the case of a system that generates DC power, such as a fuel cell or photovoltaic power generation, the power converter 13 does not require the converter 14 that converts AC voltage to DC voltage, and the inverter 15 directly converts the generated voltage to the AC voltage. It should be converted to.

  In the above-described embodiment, the current transformer 45 has been described as also serving as a system energization detection unit that detects the energization / power failure state of the system. However, the current transformer 45 may include a system energization detection unit separately from the current transformer 45. I do not care.

The block diagram which shows schematic structure of the electric power generation system which concerns on this invention The block diagram which shows the system structural example which concerns on the heat supply with respect to the power generation system waste heat recovery, hot water supply, and heating load which concerns on this invention Simplified configuration diagram illustrating the power generation system according to the present invention with an emphasis on connection relations The block diagram which shows the component for operating switching control among the components of the control part with which the electric power generation unit of the electric power generation system which concerns on this invention is equipped.

Explanation of symbols

1: Power generation system according to the present invention 10: Power generation unit 11: Gas engine 12: Generator 13: Power converter 14: Converter 15: Inverter 18: Control unit 19: Heat exchanger 20: Waste heat utilization hot water supply and heating unit 21: Hot water storage tank 22: Waste heat recovery cooling circulation pipe 23: Hot water circulation pipe 24: Waste heat recovery heat exchanger 25: Hot water supply output pipe 26: Heating output circulation pipe 27: Heating heat exchanger 28: Water supply pipe 29: Heating terminal circulation pipe 30: Heating terminal branch pipe 31: Auxiliary heat source 32: Control unit 33, 34, 35: Circulation pump 36: On-off valve 37: Three-way valve 38: Three-way valve 40: First distribution board 41: Second distribution board 42: Main breaker 43: Breaker 44: Breaker 45: Current transformer (system energization detection part)
46: Branch breaker 47, 48: Switch 50: Connection switching unit 51, 52: Switch 60: Commercial power supply 61: Electric power load 62: Electric power load 70: Hot water supply load 71: Heating terminal 90: Status signal input receiving unit 91: Storage unit 92: Control content determination unit 93: Control signal output unit

Claims (3)

  1. A generator for generating electricity by receiving an external energy source;
    A first state in which power is supplied from a commercial power source to a predetermined power load, and a second state in which power is not supplied from the commercial power source to the predetermined power load and power generated by the generator is supplied. A connection switching unit configured to be switchable between states;
    A control unit that performs switching control of the connection switching unit,
    The control unit is
    After the power system that constitutes the commercial power supply has shifted from the power failure state to the power supply state, the power supply state has continued for a predetermined specified time or longer that allows recognition that the power system has returned from the power failure state. When detected, the power generation system performs control to switch the connection switching unit from the second state to the first state.
  2. A system energization detection unit that determines whether the power system is in a power outage state or an energization state,
    The system energization detection unit transmits a signal indicating the state change to the control unit when the power system changes from a power outage state to an energization state and when the power system changes from an energization state to a power outage state. The power generation system according to claim 1.
  3.   After the control unit switches the connection switching unit from the second state to the first state, the control unit performs control to interconnect the generator disconnected from the power system to the power system. The power generation system according to claim 1 or 2, characterized by the above.
JP2008131903A 2008-05-20 2008-05-20 Power generation system Pending JP2009284590A (en)

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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012010491A (en) * 2010-06-25 2012-01-12 Hitachi Ltd Two input electronic device
JP2012017908A (en) * 2010-07-08 2012-01-26 Panasonic Electric Works Co Ltd Hybrid hot-water supply system
JP2012175836A (en) * 2011-02-22 2012-09-10 Osaka Gas Co Ltd Power generation system
JP2013055819A (en) * 2011-09-05 2013-03-21 Sumitomo Electric Ind Ltd Power generation control system and power conditioner
JP2013183612A (en) * 2012-03-05 2013-09-12 Sanyo Electric Co Ltd Control unit and power distribution system
JP2013183613A (en) * 2012-03-05 2013-09-12 Sanyo Electric Co Ltd Controller, converter, control method, and power distribution system
JP2013183611A (en) * 2012-03-05 2013-09-12 Sanyo Electric Co Ltd Controller, converter, control method, and power distribution system
JP2013188038A (en) * 2012-03-09 2013-09-19 Aisin Seiki Co Ltd Cogeneration system
JP2013243872A (en) * 2012-05-22 2013-12-05 Aisin Seiki Co Ltd Cogeneration system
WO2014080599A1 (en) * 2012-11-26 2014-05-30 パナソニック株式会社 Power supply system, power conversion apparatus, and measurement point switching apparatus
JP2015047020A (en) * 2013-08-28 2015-03-12 大和ハウス工業株式会社 Power supply system
JP2016187303A (en) * 2012-08-06 2016-10-27 京セラ株式会社 Management system, management method, control device, and power conditioner
JP6423497B1 (en) * 2017-08-01 2018-11-14 株式会社興和電設 Power control system and power control method

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6248228A (en) * 1985-08-22 1987-03-02 Mitsubishi Electric Corp Generator security apparatus
JP2006217767A (en) * 2005-02-07 2006-08-17 Honda Motor Co Ltd Cogeneration device

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6248228A (en) * 1985-08-22 1987-03-02 Mitsubishi Electric Corp Generator security apparatus
JP2006217767A (en) * 2005-02-07 2006-08-17 Honda Motor Co Ltd Cogeneration device

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012010491A (en) * 2010-06-25 2012-01-12 Hitachi Ltd Two input electronic device
JP2012017908A (en) * 2010-07-08 2012-01-26 Panasonic Electric Works Co Ltd Hybrid hot-water supply system
JP2012175836A (en) * 2011-02-22 2012-09-10 Osaka Gas Co Ltd Power generation system
JP2013055819A (en) * 2011-09-05 2013-03-21 Sumitomo Electric Ind Ltd Power generation control system and power conditioner
US9647493B2 (en) 2012-03-05 2017-05-09 Panasonic Intellectual Property Management Co., Ltd. Control device and power distribution system
JP2013183612A (en) * 2012-03-05 2013-09-12 Sanyo Electric Co Ltd Control unit and power distribution system
JP2013183613A (en) * 2012-03-05 2013-09-12 Sanyo Electric Co Ltd Controller, converter, control method, and power distribution system
JP2013183611A (en) * 2012-03-05 2013-09-12 Sanyo Electric Co Ltd Controller, converter, control method, and power distribution system
US9692257B2 (en) 2012-03-05 2017-06-27 Panasonic Intellectual Property Management Co., Ltd. Control device, conversion device, control method, and electricity distribution system
JP2013188038A (en) * 2012-03-09 2013-09-19 Aisin Seiki Co Ltd Cogeneration system
JP2013243872A (en) * 2012-05-22 2013-12-05 Aisin Seiki Co Ltd Cogeneration system
JP2016187303A (en) * 2012-08-06 2016-10-27 京セラ株式会社 Management system, management method, control device, and power conditioner
JPWO2014080599A1 (en) * 2012-11-26 2017-01-05 パナソニックIpマネジメント株式会社 Power supply system, power converter, measuring point switching device
US9590422B2 (en) 2012-11-26 2017-03-07 Panasonic Intellectual Property Management Co., Ltd. Power supply system, power conversion apparatus, and measurement point switching apparatus
WO2014080599A1 (en) * 2012-11-26 2014-05-30 パナソニック株式会社 Power supply system, power conversion apparatus, and measurement point switching apparatus
JP2015047020A (en) * 2013-08-28 2015-03-12 大和ハウス工業株式会社 Power supply system
JP6423497B1 (en) * 2017-08-01 2018-11-14 株式会社興和電設 Power control system and power control method

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