JP2002070606A - Engine power generator and cogeneration device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain stop due to an abnormal condition without respect to intention of a user in occurrence of the abnormal condition. SOLUTION: An ECU 38 and an inverter control part 137 detect an abnormal condition in an engine power generator 1 or a system power source 14, and if an abnormal condition is detected, a parallel operation relay 135 is opened so as to carry out the parallel off of the system. This parallel off is informed to the ECU 38, and the ECU 38 stops the engine. In detection of the abnormal condition, the inverter control part 137 stores the abnormal condition contents in a non-volatile memory. In response to a starting instruction of the engine 11, stored information in the non-volatile memory is read, and if the abnormal condition is recognized, engine starting and release of the parallel off is prevented for maintaining the abnormal condition stopping condition until an abnormal condition releasing operation is carried out by an operator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine generator and a cogeneration system, and more particularly to an engine generator having an interconnection function with an electric power system, such as a private power generator or a small cogeneration system, and this engine generator. The present invention relates to a cogeneration device including the device.

[0002]

2. Description of the Related Art Conventionally, private power generation facilities for preparing for an emergency such as a power outage have been widely used, but recently, as described in Japanese Patent Application Laid-Open No. 8-182192, for example, interconnection with a power system has been performed. Cogeneration-type private power generation facilities, which increase the efficiency of operation by making them operate, have begun to spread. As a facility for private power generation, for example, a household cogeneration device having a small generator driven by a gas engine using gasoline engine, city gas, or the like as fuel is used.

In connection with a power system, a system connection technical requirement guideline which stipulates technical requirements such as an output of a power generation facility capable of connection and protection of a power system in the event of a ground fault or a short circuit accident (Ministry of International Trade and Industry) Therefore, it is desired to facilitate the interconnection of the power grid. Therefore, if the conditions stipulated in these guidelines are deviated, it is necessary to immediately disconnect the interconnection because of abnormal operation, and after the conditions are restored to the guidelines and stabilized, interconnection restart is permitted. Is done.

[0004]

The operation stop state due to the disconnection at the time of the abnormal operation must be released by the user recognizing the cause of the abnormality, and then the operation must be resumed. However, if an operation is performed by a third party to turn off the main switch and then turn on the main switch while the operation is stopped due to an abnormality, the engine control EC
U rises in the reset state, and the abnormal stop state is released. Similarly, if a power failure occurs during the above-mentioned abnormal stop and the power is restored (power recovery) from the power failure, E
There is a case where the CU is reset and the abnormal stop state is released.

[0005] In particular, a home cogeneration system using a small generator driven by a gasoline engine, a gas engine, or the like does not have a backup power supply itself or only a small capacity power supply. In many cases, the abnormal stop state may be released without the user recognizing the abnormality.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is possible to cancel the abnormal stop state based on the user's recognition even if there is a power failure and power recovery in the abnormal operation stop state. An object is to provide an engine power generation device and a cogeneration device.

[0007]

An engine power generator according to the present invention comprises an abnormality detector for detecting an abnormality of the engine generator and a system power supply, and a connection for disconnecting a system interconnection when the abnormality is detected by the abnormality detector. A system relay, a communication unit that notifies the control unit of the engine of the disconnection, an engine stop unit that stops the engine in response to the notification, and a nonvolatile memory that stores the content of the abnormality when the abnormality is detected by the abnormality detection unit Comprising a non-volatile memory, in response to an instruction to start the engine, read the storage information of the non-volatile memory,
When the abnormality is recognized based on the stored information, at least the release of the disconnection of the engine start and the release of the disconnection is prohibited until the abnormal stop release signal is supplied. There is a feature.

[0008] The present invention also provides a power failure detection method for detecting the occurrence of power failure and restoration during the disconnection of the system interconnection.
Power recovery detection means, when the power recovery is detected, reads out the storage information of the non-volatile memory, if an abnormality is recognized based on the storage information, until an abnormal stop release signal is supplied, A second feature of the present invention is that at least the release of the disconnection is prohibited during the start of the engine and the release of the disconnection.

According to the first or second feature, when an abnormality is detected, the connection to the system power supply is disconnected, and the details of the abnormality are stored in the nonvolatile memory. Then, when the engine is started, the contents stored in the non-volatile memory are referred to, and if it is determined that the engine is abnormally stopped, the engine is not started or the disconnection is not permitted unless an abnormal stop release operation is performed. , The abnormal stop state is maintained. In particular, due to the second feature, the power supply of the system power supply occurs during the abnormal stop, and the same operation is performed when the power is restored.

Further, the cogeneration system of the present invention includes an exhaust heat utilization device that utilizes exhaust heat generated by the operation of the engine power generation device, and starts the engine in response to a heat request from the exhaust heat utilization device. A third feature lies in that an instruction is provided. According to this feature, the engine is automatically started by the heat request from the exhaust heat utilization device, and the exhaust heat is effectively used in accordance with the heat request. The abnormal stop state can be maintained as it is without starting.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the engine power generator. In FIG. 1, an engine generator 10 includes an engine 11 and a generator 12, and the engine 11 drives the generator 12 to generate an alternating current according to the number of rotations. The generator 12 includes a rotor connected to the engine 11 and a stator around which a three-phase output winding is wound. The output terminal of the three-phase output winding is connected to the inverter device 13. The inverter device 13 converts the alternating current output from the generator 12 into an alternating current of the same quality (in terms of voltage, frequency, noise, etc.) as the commercial power system, and synchronizes with the phase of the commercial power system for interconnection.

More specifically, the inverter device 13 is a converter 1 for converting AC output from the generator 12 to DC.
31 and an inverter circuit 133 that converts the DC converted by the converter 131 into an AC that matches the frequency and voltage of the commercial power system, a filter circuit 134, and an interconnection relay 135. The output AC of the inverter device 13 is connected to the commercial power system 14 via a connection relay 135 and a main switch 136, and is connected to an internal (for example, home) electric load 15.

An inverter control unit 137 for controlling the inverter circuit 133 switches the FET of the inverter circuit 133, and outputs the output current Io and the converter 1
Based on the output voltage Vdc of 31 and the signal from the system protection unit 138, the protection function of the inverter circuit 133 is performed, such as controlling the opening and closing of the interconnection relay 135.

The system protection unit 138 monitors the output voltage data and the frequency data of the generator, and when these values deviate from predetermined values or at the time of a power failure of the system power supply, the system control unit 138 determines that there is an abnormality and notifies the inverter control unit 137 of the abnormality. Notify or interconnect relay 1
Opening 35 to perform a system protection function such as disconnecting the interconnection. The power failure may be determined based on the presence or absence of a jump in the phase of the system, or may be determined based on the amount of phase change at that time by shifting the phase of the inverter output relative to the system. The inverter control unit 137 is provided with a non-volatile memory such as an EEPROM for storing the contents of the abnormality when the abnormality occurs in the inverter device 13 and the commercial power system 14 and the operation stop (abnormal stop) due to the occurrence of the abnormality.

The interconnection relay 135 is closed during the interconnection operation of the inverter 13 and is opened and disconnected when the operation of the inverter 13 is stopped. The interconnection relay 135 also functions as a cutoff device for system protection, and is disconnected when the system is abnormal. The opening and closing of the interconnection relay 135 is controlled by the inverter control unit 137 and the system protection unit 138 which can be constituted by a microcomputer, but is opened (disconnected) when the main switch 136 is turned off.

An ECU 38 is provided to control the engine 11. When the interconnection relay 135 is disconnected even after a predetermined time has elapsed, the ECU 38 controls the engine 1
1 stop command is output. The ECU 38 is provided with a non-volatile memory such as an EEPROM for storing the details of the abnormality and the abnormal stop when an abnormality occurs in the engine generator 10, and a display unit such as an LED for displaying the abnormal stop.

A communication unit 139 is provided for the ECU 38, the inverter control unit 137, and the system protection unit 138 (herein, the ECU side may be referred to as the inverter control side) to notify each other of the status. The power for driving and the power for controlling the engine generator 10 and the inverter device 13 are supplied from a power supply unit 140 connected to the output side of the inverter device 13.

A mixture of air and gas mixed by the mixer 33 is introduced into the engine 11. Gas suction pipe 3
A proportional valve 35 is provided in the middle of 4, and the air-fuel ratio is adjusted by the opening degree of the proportional valve 35. The air-fuel mixture burns in the engine 11 and is exhausted from the exhaust pipe 36. An oxygen concentration sensor 37 is provided in the exhaust pipe 36. ECU38
Adjusts the proportional valve 35 based on the oxygen concentration in the exhaust gas sensed by the oxygen concentration sensor 37 to control the air-fuel ratio of the air-fuel mixture to the stoichiometric air-fuel ratio. Until the oxygen concentration sensor 37 is activated, the engine 11 performs the lean burn operation with no load to reduce the emission of harmful substances to a specified value or less.

FIGS. 2 and 3 are flowcharts showing the operation of the engine generator control side (ECU side) and the inverter control device side when the engine generator 10 is started. The following processing is started when the main switch 136 is turned on and after an abnormality occurs and the engine 11 is stopped.

First, the processing on the ECU 38 side will be described with reference to FIG. In step S1, it is determined whether or not the engine 11 is abnormally stopped by referring to the contents of the nonvolatile memory. If the abnormal stop is being performed, the process proceeds to step S4 while retaining the memory of the abnormal stop, and the abnormal stop is displayed by the LED or the like so that the user can recognize it. If the engine 11 is not abnormally stopped, the process proceeds to step S2 to determine whether the cause of the abnormal stop is an abnormality of the inverter device 13. This determination is made with reference to the contents of the abnormality stored in the nonvolatile memory.

If the inverter 13 is abnormally stopped, the process proceeds to step S4. If the inverter 13 is not abnormally stopped, the process proceeds to step S3.

If the engine 11 is abnormally stopped, or if the engine 11 is stopped due to an abnormality in the inverter unit 13 even if the engine 11 is not stopped due to an abnormality, the process proceeds to step S4 with the memory of the abnormal stop maintained. After performing the abnormal stop display in step S5, it is further determined in step S5 whether or not the user has performed an abnormal stop release operation. Then, after waiting for the abnormal stop release operation (Yes at Step S5), the process proceeds to Step S3. Operation switch for canceling abnormal stop (not shown)
Is preferably provided separately from the main switch 136 so that the user's intention to cancel the abnormal stop can be clearly recognized.

In step S3, it is determined whether there is a heat request (heat request) supplied from the controller (FIG. 5) for detecting the magnitude of the heat load, that is, whether there is a command to start the engine 11. The hot water storage tank as a heat load and the controller will be described later.

If there is a heat request, the process proceeds to step S6, where it is determined whether or not the engine 11 is currently abnormal. If there is no abnormality, the process proceeds to step S7, in which the communication unit 139 is energized to inquire the inverter control unit 137 about the state of the inverter device 13. In step S8, it is determined based on the response from the inverter device 13 whether or not the inverter device 13 is currently abnormal. If there is no abnormality in the inverter device 13, the process proceeds to step S9, and the engine 11 is started. The start of the engine 11 is notified from the communication unit 139 to the inverter control unit 137.

In step S10, it is determined whether or not the oxygen concentration sensor 37 has been activated. If it is determined that the oxygen concentration sensor 37 has been activated, an "inverter start permission" is transmitted to the inverter control unit 137 to start the inverter. Whether or not the oxygen concentration sensor 37 has been activated can be determined from the fact that a predetermined time has elapsed since the start of the engine, or that the environmental temperature of the oxygen concentration sensor 37 has reached the predetermined temperature.

Next, referring to FIG.
The process of Step 37 will be described. After turning on the main switch 136, it is determined in step S12 whether or not a power failure has been detected based on the contents of the nonvolatile memory. If a power failure has been detected, the process proceeds to step S13, waits for a predetermined time (for example, 150 seconds), and then proceeds to step S14. If a power failure has not been detected, the process proceeds to step S14.

The following effects are obtained by waiting for the scheduled time in step S13. In some cases, a power company temporarily restores a power failure in order to identify a power failure location. Further, once a power failure occurs, a power failure may occur again after a short time even if the power is restored. Therefore, the main switch 1
If a power failure occurs while the power supply 36 is on, and the power generator starts up after a momentary power recovery, it may adversely affect the investigation of the cause of the power failure. On the other hand, for example, 15
By providing a waiting time of 0 seconds, adverse effects can be avoided.

In step S14, it is determined whether there is any abnormality in the power system. If there is no abnormality on the system side, step S1
At 5, it is determined whether there is any abnormality in the inverter device 13 at present. If there is no abnormality in the inverter device 13, step S
At 17, abnormality detection of the generator 12 is started. If there is an abnormality in the inverter device 13, "inverter abnormality" is stored in step S18, and the process returns to step S14.

When it is determined in step S14 that the power system is abnormal, step S1 is performed until the power system is cleared.
Continue the judgment of 4. The contents of the non-volatile memory storing the abnormality of the inverter device 13 are cleared by the abnormality canceling operation by the user (when the result of step S5 is affirmative), and the inverter abnormality is canceled. The presence or absence of an abnormality in the inverter device 13 is returned to the ECU 38 in response to the inquiry in step S7.

In step S19, the rectified DC voltage Vdc
Is greater than or equal to a predetermined value (for example, 380 V). If the DC voltage Vdc is equal to or more than the predetermined value, the process proceeds to step S20, and the “inverter start permission” transmitted in step S1 is transmitted.
To close the interconnection relay 135 to start system interconnection.

In step S21, the output of the inverter device 13 is increased. In step S22, it is determined whether or not the DC voltage Vdc is maintained at or above a predetermined value (for example, 380 V). If the voltage Vdc is equal to or higher than the predetermined value, step S
Proceeding to 23, it is determined whether or not the output has reached a rated output (for example, 1 kW). If the output has not reached the rating, the process proceeds to step S21 to further increase the output. If the output reaches the rating, it is determined that the inverter has been started normally, and the inverter abnormality determination at the time of startup ends. Thus, step S
In steps S21 to S23, a soft start for gradually increasing the output is executed.

On the other hand, as a result of increasing the output of the inverter device 13, when the DC voltage Vdc falls below the predetermined value even though the rated output has not been reached (No at Step S23), Steps S22 to S22 are performed. Proceed to S24. In step S24, it is determined whether or not the determination that the DC voltage Vdc has not reached the predetermined value has been repeated a predetermined number of times (for example, five times). If this judgment is affirmative, generator 1
2 is determined to be faulty, the grid connection is released, and the inverter control processing is stopped. If step S24 is negative, the process proceeds to step S25 to cancel the system interconnection. Then, after waiting for a predetermined time (for example, 150 seconds) in step S26, the process proceeds to step S20 to restart the system interconnection. Note that instead of shifting from step S26 to step S20, the process may advance to step S19.

Further, if step S19 is negative, the process proceeds to step S27, and it is determined whether or not the DC voltage Vdc is lower than the scheduled value continuously for a scheduled time (for example, three minutes). When step S27 is affirmative or when step S24 is affirmative, it is determined that the generator 12 has failed, and
Proceed to 24a. In step S24a, the fact that the generator 12 has failed is stored in the memory, and the inverter control process is stopped.

Next, processing when a heat request is turned off after startup or when an abnormality occurs will be described. FIG.
6 is a flowchart showing the processing of FIG. In step S30, it is determined whether the heat request is off. If the heat request is off, the engine 11 is stopped in step S31. After stopping the engine 11, step S3
Proceed to (FIG. 2) and wait until the heat request is turned on. When the engine 11 is stopped by turning off the heat request, a heat request off is transmitted to the inverter control device 13.

If the heat request is on, step S
Proceeding to 32, it is determined whether the engine 11 is abnormal. If the engine 11 is abnormal, the process proceeds to step S33, and the engine 11 is stopped. If the engine 11 is stopped, the process proceeds to step S34 to record "engine abnormality" in the nonvolatile memory, and then proceeds to step S1. When the engine 11 is stopped due to an abnormality of the engine 11, the inverter control device 13 is notified that the engine 11 has been stopped.

If there is no abnormality in the engine 11, the process proceeds to step S35. In step S35, the inverter control unit 1
It is determined whether or not an error has been received from the inverter device 13 through communication with the communication device 37. When an abnormality is received from the inverter device 13, the process proceeds to step S36, and the engine 11 is stopped. In step S37, "inverter device abnormality" is recorded in the nonvolatile memory, and then the process proceeds to step S1.

If no abnormality has been received from the inverter device 13, the process proceeds to step S38, where the inverter controller 1
It is determined whether or not a system abnormality has been received by communication with 37. If no system abnormality is received, the process proceeds to step S30.
If a system abnormality has been received, the process proceeds to step S39 to stop the engine, and then proceeds to step S3.

Next, the processing of the inverter control device 13 will be described with reference to FIG. In step S40, it is determined whether a heat request-off has been received from the ECU 38. If the determination is affirmative, the system interconnection is released in step S41, and the process proceeds to step S12 (FIG. 3). If the heat request OFF has not been received, the process proceeds to step S42, and it is determined whether or not the stop of the engine 11 has been received. If the stop of the engine 11 has been received, step S
At 43, the system interconnection is released, and the process proceeds to step S12. If the stop of the engine 11 has not been received, step S44
Is used to determine whether or not the inverter device 13 is abnormal. If there is an abnormality in the inverter device 13, the process proceeds to step S45 to release the system interconnection, and then proceeds to step S12.

If there is no abnormality in the inverter device 13, it is determined in step S46 whether there is an abnormality in the system. If there is no system abnormality, the process proceeds to step S47 to determine whether or not the system is being interconnected. If the system is interconnected, the process proceeds to step S40.

If it is determined in step S46 that the system is abnormal, the flow advances to step S51 to cancel the system interconnection.
In step S52, it is determined whether a power failure has been detected.
If a power failure is detected, the fact that the power failure has been detected is recorded in the nonvolatile memory in step S53, and the process proceeds to step S54. If no power failure has been detected, the process skips step S53 and proceeds to step S54. In step S54, it is determined whether the system abnormality has continued for a predetermined time (for example, 5 minutes). If the system abnormality has not continued for the scheduled time, the process proceeds to step S47. If the system is not connected to the grid, step S4
Proceed to 8 to judge whether there is an abnormality in the system. If there is a system abnormality, the process proceeds to step S40. If there is no system abnormality, the process proceeds to step S49 to wait for a scheduled time (for example, 150 seconds) and then proceeds to step S50. In step S50, system interconnection is started. If the system abnormality continues for the scheduled time, step S55
And sends a command to stop the engine 11 to the ECU 38. In step S56, it is determined whether there is a system abnormality. If the system abnormality has been resolved, the process waits for a predetermined time (for example, 150 seconds) in step S57, and then proceeds to step S12 (FIG. 3).

Next, a cogeneration system including the exhaust heat utilization device of the engine generator will be described. In the block diagram of FIG. 6, the same reference numerals as those in FIG. 1 indicate the same or equivalent parts. The engine 11 generates heat as the generator 12 operates, and this heat is recovered by heat exchange in the heat recovery device 16 of the engine 11. This heat recovery is preferably performed on all high-temperature portions such as the muffler of the engine 11. Cooling water in a pipe 18 passing through the heat recovery device 16 is circulated by a pump 19, and heat is transferred to the hot water storage tank 17 using the cooling water as a medium. The hot water storage tank 17 is provided with a first heat exchanger 20 connected to a pipe 18, and water supplied to the hot water storage tank 17 from a water supply source 31 via a valve 32 is heated by the first heat exchanger 20. And get warm water. The hot water stored in the hot water storage tank 17 is supplied to a water heater 21 as a first heat load to be used and consumed.

Above the first heat exchanger 20, a second heat exchanger 22 is provided. A heating device 24 as a second heat load such as a central heating system or a floor heating system is connected to a pipeline 23 connected to the second heat exchanger 22, and the hot water in the hot water storage tank 17 is supplied to the water heater 21. Constitutes a second hot water path that is independent of the hot water path that supplies the water.
With this second hot water path, heat can be efficiently and secondarily recovered from the hot water storage tank 17.

The reheating boiler 2 is provided in the second hot water path.
5 and a three-way valve 26 are provided. Reheating boiler 2
5 is provided with a pump 27 for circulating hot water in the second hot water path. The three-way valve 26 is switching means for circulating hot water to the bypass 28 side or the heating device 24 side. When the three-way valve 26 is switched to the heating device 24 side, the hot water discharged from the hot water storage tank 17 reheats the boiler 2.
A hot water path returning to the hot water storage tank 17 via the heating device 5 and the heating device 24 is formed. On the other hand, when the three-way valve 26 is switched to the bypass 28 side, the hot water flowing out of the hot water storage tank 17 passes through the reheating boiler 25 and then returns to the hot water storage tank 17 via the bypass 28 without passing through the heating device 24. Is formed.

A temperature sensor TS 1 is provided in the hot water storage tank 17, and temperature information T 1 of the hot water detected by the temperature sensor TS 1 is supplied to the controller 29. Temperature sensor T
S1 is desirably installed at an appropriate height in the hot water storage tank 17 from near the upper end of the first heat exchanger 20 to near the lower end of the second heat exchanger 22.

The controller 29 controls the start and stop of the engine 11 based on the temperature information T1. That is, the temperature information T1 indicates the heat demand of the water heater 21 that directly uses the hot water in the hot water storage tank 17 or the heating device 24 that uses the hot water indirectly through the second heat exchanger 22. If the temperature information T1 is equal to or lower than the reference temperature Tref-1, the controller 29 determines that the heat demand is large and outputs a heat request to the ECU 38 to drive the engine 11 to generate heat. Let it. When the temperature information T1 becomes equal to or higher than the reference temperature Tref-1, the hot water storage tank 17
Then, it is determined that a sufficient amount of heat has been stored therein, the heat request is turned off, and the engine 11 is stopped.

The reference temperature Tref-1 is determined by the type and size of the heat load (that is, the type and size of the water heater 21 and the heating device 24),
It is determined based on the heat output of engine generator 10, the capacity of hot water storage tank 17, and the like. The reference temperature Tref-1 has a hysteresis for stable operation of the engine 11, that is, for avoiding frequent starting and stopping.

When the engine 11 is driven based on the temperature information T1, the engine 12 may be operated so that the generator 12 outputs a constant generated power, or the generated power corresponding to the magnitude of the power load 15 is generated. It may be operated in a power load following type so as to output. In the constant power generation type, the engine 11 as a driving source can be set to a rated operation in which the number of revolutions of the engine 11 is substantially constant. Therefore, a highly efficient operation in which the fuel consumption is small and the exhaust gas condition is good. Is possible.
Here, when a shortage occurs in the power generated by the generator 12 due to a large power demand, the shortage can be covered by the power from the commercial power supply 14.

The water temperature in the hot water storage tank 17 largely depends on the amount of hot water consumed, that is, the amount of heat demand, and the operation method of the engine generator 10, that is, whether it is a constant power generation output type or a power load following type. For example, when the hot water consumption is small, the water temperature can be maintained at about 80 ° C. by operating the engine generator 10 based on the water temperature detected by the temperature sensor TS1. However, the temperature of the hot water in the hot water storage tank 17 decreases when hot water is rapidly used in large quantities, such as when heat demand is generated in both the water heater 21 and the heating device 24, or when the system is started. In some cases, the temperature of the supplied water is only about the temperature of the supplied water.

The reheating boiler 25 functions effectively when the water temperature in the hot water storage tank 17 cannot be maintained at the reference temperature only by the recovered heat from the engine generator 10. The hot water controller 30 determines that the water temperature T1 in the hot water storage tank 17 is lower than the reference temperature Tref-1.
When the value falls below ref-L, both the reheating command B and the switching command C are turned on. When the reheating command B is on, the reheating boiler 25 is driven, and when the switching command C is on, the three-way valve 26 is switched to the bypass 28 side. Thereby, the hot water heated by the reheating boiler 25 circulates through the pipeline 23, and the heated hot water raises the temperature of the water in the hot water storage tank 17 through the second heat exchanger 22.

A second temperature sensor TS2 is provided above the temperature sensor TS1, and when the temperature information T1 becomes lower than the reference temperature Tref-1, or when the temperature information T2 detected by the temperature sensor TS2 is lower than the reference temperature Tref-1. Tref-2 (> Tref-
1) When the following conditions are satisfied, the controller 29
8, a heat request may be output.

The engine generator 10 includes a temperature sensor TS1
Is stopped when the temperature information T1 according to the above becomes equal to or higher than a reference temperature Tref-3 (for example, 70 ° C.) set higher than the reference temperature Tref-1. Temperature information T by temperature sensor TS1
If 1 has reached the reference temperature Tref-3, it can be determined that the amount of heat stored in the hot water storage tank 17 is sufficient.

The control example of the start / stop of the engine generator 10 based on the magnitude of the heat load represented by the water temperature in the hot water storage tank 17 is described in Japanese Patent Application No. 11-131, filed by the present applicant.
This is described in more detail in the specification of US Pat.

[0053]

As is apparent from the above description, according to the first to fourth aspects of the present invention, when an abnormality occurs in the power generator or the system power supply, the operation is stopped abnormally and the contents of the abnormality are stored in the nonvolatile memory. Is stored. When there is an instruction to start the engine, or when a power failure or power recovery occurs, the contents stored in the non-volatile memory are referred to. The abnormal stop state is released only by the operation.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an engine power generator according to one embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the ECU at the time of startup.

FIG. 3 is a flowchart showing an operation of the inverter control device at the time of startup.

FIG. 4 is a flowchart showing the operation of the ECU when an abnormality occurs.

FIG. 5 is a flowchart illustrating an operation of the inverter control device when an abnormality occurs.

FIG. 6 is a block diagram illustrating a configuration of a cogeneration device according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Engine generator, 11 ... Engine, 12 ... Generator, 13 ... Inverter apparatus, 14 ... Commercial power system, 16 ... Water cooling system, 17 ... Hot water storage tank, 20 ...
1st heat exchanger, 21 ... Hot water heater, 22 ... Second heat exchanger, 24 ... Heating device, 25 ... Reheating boiler, 2
6 ... three-way valve, 29 ... controller, 30 ... hot water controller, 35 ... proportional valve, 37 ... oxygen concentration sensor,
38 ECU, 131 converter, 133 inverter circuit, 135 interconnection relay, 136 main switch, 137 inverter control unit, 138 system protection unit, 139 communication unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02G 5/04 F02G 5/04 HRS H02P 9/00 H02P 9/00 B 9/04 9/04 J 9/08 9/08 B (72) Inventor Yoshiaki Kotani 1-4-1 Chuo, Wako-shi, Saitama F-term in Honda R & D Co., Ltd. (Reference) 3G084 AA06 BA00 BA13 BA33 CA01 CA07 DA28 EA07 EB06 EB22 EC01 FA03 FA29 FA36 3G093 AA16 BA04 CA01 DA00 DA12 DA13 DB19 EB08 5H590 AA11 AB13 CA26 CE01 EA05 GA02 GA09 GB05 HA02 HA09 HA19 JB02 JB10 KK06 KK07

Claims (4)

[Claims] An engine power generation device that links the power output of a generator driven by an engine to a system power supply, wherein the abnormality detection means detects an abnormality in the engine power generation device and the system power supply; An interconnection relay for disconnecting a system interconnection when an abnormality is detected; a communication unit for notifying the disconnection to a control unit of the engine; an engine stop unit for stopping an engine in response to the notification; and the abnormality detection unit A non-volatile memory for storing the details of the abnormality when an abnormality is detected, reading out the storage information of the non-volatile memory in response to the engine start instruction, and recognizing the abnormality based on the stored information. Until the abnormal stop release signal is supplied, at least the release of the disconnection among the starting of the engine and the release of the disconnection is prohibited. Engine power generator. 2. An engine power generating device that links a power output of a generator driven by an engine to a system power supply, wherein the abnormality detecting means detects an abnormality of the engine power generating device and the system power supply; An interconnection relay for disconnecting a system interconnection when an abnormality is detected; a communication unit for notifying the disconnection to a control unit of the engine; an engine stop unit for stopping an engine in response to the notification; and the abnormality detection unit A non-volatile memory for storing the content of the abnormality when an abnormality is detected by the system, and a power failure / recovery detecting means for detecting that a power failure and a power failure have occurred during the disconnection of the system interconnection. When the abnormality is detected, the storage information of the nonvolatile memory is read out, and if an abnormality is recognized based on the storage information, the engine is started until the abnormal stop release signal is supplied. Of releasing the reserve the disconnection, the engine generator apparatus characterized by being configured so as to prohibit the release of at least disconnecting. 3. An engine power generator according to claim 1 or 2, and an exhaust heat utilization device utilizing exhaust heat generated by operating the engine power generator, wherein the heat request from the exhaust heat utilization device is provided. A cogeneration apparatus characterized in that a start instruction is supplied to the engine in response. 4. The hot water storage device for storing the first hot water produced by using the exhaust heat of the engine power generator according to claim 1 or 2, wherein the waste heat utilization device produces the first hot water. A first heat exchanger provided in the hot water storage tank; and a second heat exchanger provided above the first heat exchanger for extracting heat from the first hot water to produce second hot water; A temperature sensor installed between the vicinity of the upper end of the first heat exchanger and the vicinity of the lower end of the second heat exchanger; and supplying a heat request to the engine power generator based on the temperature detected by the temperature sensor. The cogeneration apparatus according to claim 2, further comprising a controller that performs the operation.