JP2009236411A - Cogeneration system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cogeneration system improving durability and capable of reducing a carbon dioxide generation amount. <P>SOLUTION: The cogeneration system is composed such that in an operation control means, at periodic operation form selecting timing, an operation form selecting process is executed determining an operation form of a cogeneration device 1 in any one of a continuous operation form, an intermittent operation form, or a standby form on the basis of a predicted energy consumption during continuous operation, a predicted energy consumption during intermittent operation, and an operation form selecting condition determined on the basis of predicted load power in time sequence and heating efficiency of an auxiliary heating means 28. The operation control means is composed to determine the predicted energy consumption during the continuous operation and the predicted energy consumption during the intermittent operation as the heating efficiency of the auxiliary heating means 28 by using heating efficiency for operation form selection determined at a value lower than heating efficiency a latent heat recovery type auxiliary heating means 28 in the operation form selecting process. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention is provided with a combined heat and power device that generates both electric power and heat, a combustion type latent heat recovery type auxiliary heating means, and an operation control means for controlling operation,
When the operation control means continuously operates the cogeneration device based on the time-series predicted load power, the time-series predicted load heat amount, and the heat generation efficiency of the auxiliary heating means at the periodic operation mode selection timing. The predicted energy consumption during continuous operation when it is assumed and the predicted energy consumption during intermittent operation when it is assumed that the combined heat and power supply device is intermittently operated are obtained. Based on the predicted energy consumption at the time of intermittent operation and the operation mode selection condition, any of the operation mode of the combined heat and power supply device is a continuous operation mode, the intermittent operation mode or the standby mode in which the combined heat and power supply device is stopped and waits for the operation. The present invention relates to a cogeneration system configured to execute an operation mode selection process defined in the above.

Such a cogeneration system is installed in a general household, consumes the generated power of the combined heat and power device in an electrical device, etc., and consumes the heat generated from the combined heat and power supply device in a hot water storage tank, or a heating terminal The hot water stored in the hot water tank is supplied to a hot water supply destination such as a kitchen or a bath.
In addition, the amount of heat supplied by the hot water supply destination cannot be covered by the hot water in the hot water storage tank, and the amount of heat generated by the combined heat and power supply device that supplies the heating load in the space to be heated to the heating terminal cannot be covered by the combustion type auxiliary. It will be supplemented by heating means.

  Then, an operation mode selection process is executed at a periodic operation mode selection timing. In the operation mode selection process, the time-series predicted load power, the time-series predicted load heat amount, and the heat generation efficiency of the auxiliary heating means are used. The predicted energy consumption during continuous operation and the predicted energy consumption during intermittent operation are obtained, and based on the obtained predicted energy consumption during continuous operation, predicted energy consumption during intermittent operation, and operation mode selection conditions The operation mode of the combined heat and power supply apparatus is configured to be determined as one of a continuous operation mode, an intermittent operation mode, and a heat standby mode (see, for example, Patent Document 1).

  By the way, although it is not clearly described in the Patent Document 1, it is considered that a non-latent heat recovery type is provided as an auxiliary heating means in the Patent Document 1, but in recent years, energy saving has been reduced. For this purpose, there may be provided a latent heat recovery type auxiliary heating means having higher heat generation efficiency than the non-latent heat recovery type.

JP 2006-125701 A

However, conventionally, when a latent heat recovery type auxiliary heating means is provided, the operation mode selection process uses the heat generation efficiency of the latent heat recovery type auxiliary heating means as the heat generation efficiency of the auxiliary heating means to predict the continuous operation. The energy consumption and the predicted energy consumption during intermittent operation will be calculated, but the latent heat recovery type is equivalent to the fact that the heat generation efficiency of the latent heat recovery type auxiliary heating means is higher than that of the non-latent heat recovery type auxiliary heating means. Compared with the heat generation efficiency of the non-latent heat recovery type auxiliary heating means, the amount of heat generated by the combined heat and power unit is calculated with respect to the time-series predicted load heat amount. The predicted energy consumption of the auxiliary heating means to cover the amount that cannot be covered is expected to be small.
Since the intermittent operation mode generates less heat in the combined heat and power device than the continuous operation mode, the intermittent operation mode increases the predicted energy consumption of the auxiliary heating unit, but the latent heat recovery type auxiliary heating unit By using the heat generation efficiency, the predicted energy consumption of the auxiliary heating means is expected to be small. Therefore, the intermittent energy operation tends to be less demanded than the continuous operation mode, and the operation mode For example, the operation mode of the combined heat and power device is determined as the operation mode with the larger amount of predicted energy reduction predicted to be reduced by operating the combined heat and power device among the continuous operation mode and the intermittent operation mode. In such a case, there is a high possibility that the operation mode of the combined heat and power supply apparatus is set to the intermittent operation mode.
Further, based on the predicted energy consumption during continuous operation and intermittent operation obtained using the heat generation efficiency of the latent heat recovery type auxiliary heating means, the operation mode of the combined heat and power supply device is determined as the intermittent operation mode. The possibility that the operation time of the combined heat and power supply apparatus is set short is increased.

By the way, in order to improve the durability of the cogeneration system by reducing the number of start and stop times of the combined heat and power device and auxiliary equipment, the possibility that the operation mode of the combined heat and power device is determined to be the continuous operation mode is increased. Preferably, in order to reduce the amount of carbon dioxide generated, the possibility that the operation mode of the combined heat and power device is determined to be the continuous operation mode is increased in order to increase the time to cover the load power with the combined heat and power device. Although preferable, conventionally, there has been a problem that the operation mode of the combined heat and power supply apparatus is likely to be determined as an intermittent operation mode.
In addition, when the operation mode of the combined heat and power device is set to the intermittent operation mode, it is preferable to lengthen the operation time of the combined heat and power device in order to reduce the amount of carbon dioxide generated. When the operation mode is determined as the intermittent operation mode, there is a problem that the operation time of the combined heat and power supply apparatus is likely to be set short.

Hereinafter, an explanation will be given on the point that the carbon dioxide generation amount can be reduced as the operating time of the combined heat and power supply device is lengthened.
That is, the basic unit in the carbon dioxide generation of the thermal power plant is, for example, 0.69 kg / kWh, and the basic unit in the carbon dioxide generation of city gas (for example, 13A mainly composed of natural gas) is, for example, 0.00. 0509 kg / MJ.
The carbon dioxide generation amount Q1 when the load power is supplied by commercial power, and the carbon dioxide generation amount when the load power is supplied by a fuel cell as a combined heat and power supply device are obtained by the following formulas 1 and 2, respectively. .
Q1 = Load power x CO2 emission intensity of thermal power plant ......... (Formula 1)
Q2 = (Load power / Power generation efficiency) x 3.6 x City gas CO2 emission intensity ............... (Formula 2)
However, “3.6” in Equation 2 is a conversion factor from kWh to MJ.

  When the load power is 0.75 kWh, the carbon dioxide generation amount Q1 when the load power is covered by commercial power is 0.518 kg, and the carbon dioxide generation amount when the load power is generated by the combined heat and power device is the power generation efficiency. 0.32 becomes 0.429 kg, and even if only the load power is covered by the combined heat and power device, the amount of generated carbon dioxide is better when the load power is covered by the combined heat and power device than when the load power is covered by the commercial power. The amount of carbon dioxide generated can be reduced as the operating time of the combined heat and power supply device is increased.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a cogeneration system capable of improving durability and reducing the amount of carbon dioxide generated.

The cogeneration system of the present invention is provided with a combined heat and power device that generates both electric power and heat, a combustion type latent heat recovery type auxiliary heating means, and an operation control means for controlling operation,
When the operation control means continuously operates the cogeneration device based on the time-series predicted load power, the time-series predicted load heat amount, and the heat generation efficiency of the auxiliary heating means at the periodic operation mode selection timing. The predicted energy consumption during continuous operation when it is assumed and the predicted energy consumption during intermittent operation when it is assumed that the combined heat and power supply device is intermittently operated are obtained. Based on the predicted energy consumption at the time of intermittent operation and the operation mode selection condition, any of the operation mode of the combined heat and power supply device is a continuous operation mode, the intermittent operation mode or the standby mode in which the combined heat and power supply device is stopped and waits for the operation. It is configured to execute the operation type selection process defined in
In the first characteristic configuration, the operation control means is for selecting an operation mode in which the heat generation efficiency of the auxiliary heating unit is set to a value lower than the heat generation efficiency of the latent heat recovery type auxiliary heating unit in the operation mode selection process. The predicted energy consumption amount during the continuous operation and the predicted energy consumption amount during the intermittent operation are obtained using the heat generation efficiency.

  That is, the operation control means continuously uses the heat generation efficiency for selecting the operation form determined to be lower than the heat generation efficiency of the latent heat recovery type auxiliary heating means as the heat generation efficiency of the auxiliary heating means in the operation form selection process. The predicted energy consumption during operation and the predicted energy consumption during intermittent operation are obtained.

In other words, the heat generation efficiency for selecting the operation mode is lower than the heat generation efficiency of the auxiliary heating means for latent heat recovery type. Compared to the amount of heat that is calculated, the amount of energy consumed by the auxiliary heating means to cover the time series predicted load heat amount that cannot be covered by the heat generation amount of the combined heat and power unit is expected. Therefore, it is possible to increase the possibility that the operation mode of the combined heat and power supply apparatus is determined as the continuous operation mode.
When the possibility that the operation mode of the combined heat and power device is determined as the continuous operation mode increases, the number of times of starting and stopping the combined heat and power supply device and auxiliary equipment can be reduced, so that the durability can be improved.
Further, when the possibility that the operation mode of the combined heat and power device is determined to be the continuous operation mode becomes high, the operation time of the combined heat and power supply device can be lengthened, so that the amount of carbon dioxide generated can be reduced.
Therefore, it has become possible to provide a cogeneration system that can improve durability and reduce the amount of carbon dioxide generated.

In addition to the first feature configuration, the second feature configuration is
The heat generation efficiency for selecting the operation mode is determined by the heat generation efficiency of the non-latent heat recovery type auxiliary heating means.

In other words, the predicted energy consumption during continuous operation and the predicted energy consumption during intermittent operation are obtained using the heat generation efficiency for operation mode selection, and the calculated predicted energy consumption during intermittent operation and prediction during intermittent operation are obtained. Since the operation mode of the combined heat and power unit is determined based on the energy consumption, the predicted energy consumption during continuous operation and the predicted energy consumption during intermittent operation are calculated using the heat generation efficiency of the original latent heat recovery type auxiliary heating means. Compared to the required case, even if the predicted energy consumption is somewhat higher, the operation mode of the combined heat and power device tends to be determined as the continuous operation mode, but the heat generation efficiency for selecting the operation mode is a non-latent heat recovery type auxiliary heating means Therefore, the continuous operation mode with the predicted energy consumption equivalent to the case of using the non-latent heat recovery type as the auxiliary heating means is determined as the operation mode of the combined heat and power supply device. Doo is possible, even in the prescribed continuous operation mode the operating mode of the cogeneration device can be prevented from being much energy consumption.
Accordingly, it is possible to improve durability and reduce the amount of generated carbon dioxide while suppressing an increase in energy consumption.

In addition to the first or second feature configuration, the third feature configuration is
When the operation control means sets the operation mode of the combined heat and power device to the intermittent operation mode in the operation mode selection process, the operation and power supply device is operated in the intermittent operation mode with different operation time zones. For each of the cases, the predicted energy consumption during the intermittent operation is obtained using the heat generation efficiency for selecting the operation mode, and an operation time zone with a small predicted energy consumption is determined as the operation time zone of the combined heat and power unit. It is in the point comprised as follows.

That is, when the operation control means sets the operation mode of the combined heat and power device to the intermittent operation mode in the operation type selection process, each of the cases where the combined heat and power device is operated in the intermittent operation mode with different operation time zones. Then, the predicted energy consumption during intermittent operation is obtained using the heat generation efficiency for selecting the operation mode, and an operation time zone with a small predicted energy consumption is determined as the operation time zone of the cogeneration device.
In other words, for each of the cases where the combined heat and power device is operated in the intermittent operation mode with different operation time zones, the predicted energy consumption during the intermittent operation is obtained, and the operation time zone where the predicted energy consumption is small is determined as the combined heat and power device. When determining the predicted energy consumption during intermittent operation using the heat generation efficiency for selecting the operation mode, the predicted energy consumption during intermittent operation is calculated using the heat generation efficiency of the latent heat recovery type auxiliary heating means. The amount of predicted energy consumption of the auxiliary heating means increases and the predicted energy consumption during intermittent operation increases as the amount of predicted insufficient heat increases because the heat generation efficiency of the auxiliary heating means is lower than when the amount is calculated. Therefore, it is determined that the operating time zone of the combined heat and power unit should be longer so that the predicted shortage of heat is reduced and the predicted energy consumption during intermittent operation is reduced. It becomes Rukoto. The predicted insufficient heat quantity is a quantity of heat that cannot be covered by the generated heat quantity of the combined heat and power supply device in the predicted load heat quantity.
And even if the operation mode of the combined heat and power unit is determined to be an intermittent operation mode, the operation time zone of the combined heat and power unit can be lengthened, so that the amount of carbon dioxide generated can be reduced.
Therefore, since the carbon dioxide generation amount can be reduced even when the operation mode of the combined heat and power supply apparatus is set to the intermittent operation mode, the carbon dioxide generation amount can be further reduced.

The fourth feature configuration is in addition to any one of the first to third feature configurations,
When the operation control means sets the operation mode of the cogeneration device to the continuous operation mode in the operation mode selection process, and operates the cogeneration device in the continuous operation mode with different power generation outputs. For each of the above, the predicted energy consumption during the continuous operation is obtained using the heat generation efficiency of the auxiliary heating means of the latent heat recovery type, and the power generation output with the small predicted energy consumption is determined as the power generation output of the cogeneration device. It is in the point comprised as follows.

That is, the operation control means, when the operation mode of the combined heat and power device is set to the continuous operation mode in the operation mode selection process, for each of the cases where the combined heat and power device is operated in the continuous operation mode with different power generation outputs, Using the heat generation efficiency of the latent heat recovery type auxiliary heating means, the predicted energy consumption during continuous operation is obtained, and the power generation output with the small predicted energy consumption is determined as the power generation output of the combined heat and power supply device.
That is, for each of the cases where the combined heat and power device is operated in the continuous operation mode with different power generation outputs, the predicted energy consumption during the continuous operation is obtained, and the power generation output with a small predicted energy consumption is generated by the combined power and power generation device. In determining the output, when the predicted energy consumption during continuous operation is obtained using the heat generation efficiency of the auxiliary heating means of the latent heat recovery type, the predicted energy consumption during continuous operation is obtained using the heat generation efficiency for operation mode selection. Compared to the case, the heat generation efficiency of the auxiliary heating means is increased, and even if a predicted shortage of heat occurs, the predicted energy consumption of the auxiliary heating means is reduced and the predicted energy consumption during continuous operation is required to be reduced. Therefore, in order to suppress the amount of heat generated from the combined heat and power supply device, the power generation output of the combined heat and power supply device is set to be low.
And, when the combined heat and power unit is operated in the continuous operation mode, the operation time of the combined heat and power unit becomes longer than in the case of operating in the intermittent operation mode, and the integration of integrating the generated heat amount of the combined heat and power unit The amount of generated heat tends to increase, so it is easy to generate excess heat. However, it is better to operate the combined heat and power supply device with the power generation output determined using the heat generation efficiency of the latent heat recovery type auxiliary heating means. Since the power generation output of the combined heat and power unit tends to be suppressed by setting the power generation output using efficiency and the combined heat and power unit is operated, the amount of generated heat is integrated. The accumulated amount of generated heat tends to be suppressed, and the excess heat can be suppressed.
Accordingly, it is possible to improve durability and reduce the amount of carbon dioxide generated while suppressing excess heat.

In addition to any one of the first to fourth feature configurations described above, the fifth feature configuration is
The operation mode selection condition is any one of a predicted carbon dioxide emission amount, a predicted utility cost, and a predicted operation merit for each of the predicted energy consumption during the continuous operation and the predicted energy consumption during the intermittent operation. Is set as a condition for determining the operation mode of the cogeneration apparatus based on the operation mode selection index.

That is, using the predicted carbon dioxide emissions for the predicted energy consumption during continuous operation and the predicted energy consumption during intermittent operation as the operation mode selection index, the operation mode of the combined heat and power unit based on the operation mode selection index Since the operation mode of the combined heat and power supply device can be determined so as to reduce the carbon dioxide emission, the environmental performance can be improved.
Further, the predicted energy consumption during the continuous operation and the predicted energy consumption for the predicted energy consumption during the intermittent operation are used as the operation mode selection index, and the operation mode of the combined heat and power unit is determined based on the operation mode selection index. If this is done, the operating mode of the combined heat and power supply device can be determined so as to reduce the utility cost, so the economic efficiency can be improved.

The predicted driving merit as the operation mode selection index includes, for example, a predicted energy reduction amount, a predicted utility cost reduction amount, or a predicted carbon dioxide reduction amount.
The predicted energy consumption during continuous operation and the predicted energy consumption during intermittent operation are estimated energy reduction amount and predicted utility cost reduction amount as an operation mode selection index, and a combined heat and power generation device based on the operation mode selection index When the operation mode is determined, the operation mode of the combined heat and power supply apparatus can be determined so as to increase the predicted energy reduction amount and the predicted utility cost reduction amount, so that the economy can be improved.
Moreover, the predicted CO2 reduction amount for the predicted energy consumption during continuous operation and the predicted energy consumption during intermittent operation is used as an operation mode selection index, and the operation mode of the combined heat and power unit is based on the operation mode selection index. Is determined, the operation mode of the combined heat and power supply apparatus can be determined so as to increase the predicted amount of carbon dioxide reduction, so that the environmental performance can be improved.
And, if the operation mode selection condition is set to a condition that can improve the environmental performance as described above, the operation mode of the combined heat and power supply apparatus is more likely to be set to the continuous operation mode, thereby reducing the carbon dioxide generation amount. Combined with what can be done, environmental performance can be improved effectively.
Therefore, durability can be improved and environmental performance can be improved effectively, or durability can be improved and environmental performance can be improved, and economic efficiency can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
First, the first embodiment will be described.
As shown in FIGS. 1 and 2, the cogeneration system recovers the heat generated by the fuel cell 1 as a combined heat and power generation apparatus that generates electric power and heat with cooling water, and cools the cooling. A hot water storage unit 4 that uses water to store hot water in the hot water tank 2 and supply a heat medium to the heat consuming terminal 3, and an operation control unit 5 as operation control means that controls the operation of the fuel cell 1 and the hot water storage unit 4. Etc.

Since the fuel cell 1 is well-known, a detailed description and illustration thereof will be omitted. Briefly, the fuel cell 1 includes a cell stack that generates power by being supplied with a fuel gas containing hydrogen and an oxygen-containing gas. A fuel gas generation unit that generates fuel gas to be supplied to the cell stack, a blower that supplies air as an oxygen-containing gas to the cell stack, and the like are provided.
The fuel gas generation unit includes a desulfurizer for desulfurizing a hydrocarbon-based raw fuel gas such as a supplied city gas (for example, a natural gas-based city gas), a desulfurized raw fuel gas supplied from the desulfurizer, A reformer that generates a reformed gas mainly composed of hydrogen by reforming reaction with steam supplied separately, and carbon monoxide in the reformed gas supplied from the reformer with carbon dioxide. A carbon monoxide remover that selectively oxidizes carbon monoxide in the reformed gas supplied from the transformer with selective oxidation air supplied separately. The reformed gas reduced by the shift treatment and the selective oxidation treatment is supplied to the cell stack as the fuel gas.

And it is comprised so that the electric power generation output of the said fuel cell 1 may be adjusted by adjusting the supply amount of the raw fuel gas to the said fuel gas production | generation part.
A grid interconnection inverter 6 is provided on the power output side of the fuel cell 1, and the inverter 6 has the same voltage and the same frequency as the received power for receiving the generated power of the fuel cell 1 from the commercial power supply 7. It is configured to.
The commercial power supply 7 is electrically connected to a power load 9 such as a television, a refrigerator, or a washing machine via a received power supply line 8.
The inverter 6 is electrically connected to the received power supply line 8 via the generated power supply line 10, and the generated power of the fuel cell 1 is supplied to the power load 9 via the inverter 6 and the generated power supply line 10. It is configured as follows.

The received power supply line 8 is provided with load power measuring means 11 for measuring the load power of the power load 9. Does this load power measuring means 11 generate a reverse power flow in the current flowing through the received power supply line 8? It is also configured to detect whether or not.
The electric power supplied from the fuel cell 1 to the received power supply line 8 is controlled by the inverter 6 so that a reverse power flow does not occur, and the surplus power of the power generation output is recovered by replacing the surplus power with heat. 12 is configured to be supplied.

The electric heater 12 is composed of a plurality of electric heaters and is provided so as to heat the cooling water of the fuel cell 1 flowing through the cooling water circulation path 13 by the operation of the cooling water circulation pump 15. ON / OFF is individually switched by the connected operation switch 14.
The operation switch 14 is configured to adjust the power consumption of the electric heater 12 according to the amount of surplus power so that the power consumption of the electric heater 12 increases as the amount of surplus power increases. Yes.
The configuration for adjusting the power consumption of the electric heater 12 is a configuration for adjusting the output of the electric heater 12 by, for example, phase control or the like in addition to the configuration for switching ON / OFF of the plurality of electric heaters 12 as described above. You may adopt.

  The hot water storage unit 4 is configured to store hot water in a state in which temperature stratification is formed, the hot water circulating pump 17 that circulates hot water in the hot water tank 2 through the hot water circulation path 16, and the hot water for heat source through the heat source circulation path 20. The heat source circulation pump 21 for circulating the heat, the heat medium circulation pump 23 for circulating and supplying the heat medium to the heat consuming terminal 3 through the heat medium circulation path 22, and the heat exchange for hot water storage for heating the hot water flowing through the hot water circulation path 16 24, a heat source heat exchanger 25 for heating the hot water for heat source flowing through the heat source circulation path 20, a heat exchanger for heat medium heating for heating the heat medium flowing through the heat medium circulation path 22, Auxiliary heater 28 as auxiliary heating means of combustion type and latent heat recovery type for heating hot water taken out from hot water tank 2 and flowing through hot water supply path 27 and hot water for heat source flowing through circulation path 20 for heat source Be equipped It is configured Te.

The hot water circulation path 16 is connected to the bottom and top of the hot water tank 2, and the hot water tank 2 is configured to return hot water taken from the bottom of the hot water tank 2 to the top of the hot water tank 2 by the hot water circulation pump 17. Hot water is circulated through the hot water circulation path 16 and the hot water circulated through the hot water circulation path 16 is heated by the heat exchanger 24 for hot water storage so that the hot water tank 2 forms a temperature stratification. Is configured to be stored.
The hot water circulation path 16 is branched and connected so that a part thereof is in parallel, a three-way valve 18 is provided at the connection location, and a radiator 19 is provided in the branched flow path. Yes. Then, by switching the three-way valve 18, the hot water taken out from the lower part of the hot water tank 2 is circulated so as to pass through the radiator 19, and the hot water taken out from the lower part of the hot water tank 2 is circulated so as to bypass the radiator 19. It is comprised so that it may switch to the state to be made to.

  The hot water supply path 27 is connected to the hot water storage tank 2 through a location downstream of the hot water storage heat exchanger 24 in the hot water circulation path 16, and hot water in the hot water storage tank 2 is connected to the bathtub through the hot water supply path 27. A hot water supply path 29 is connected to the bottom of the hot water tank 2 so that the hot water is supplied to a hot water supply destination such as a hot water tap and a shower and the hot water tank 2 is supplied with the hot water.

  The heat source circulation path 20 is provided so as to form a circulation path in a state in which a part of the hot water supply path 27 is shared, and the heat source circulation path 20 is used for a heat source for interrupting the flow of hot water for the heat source. An intermittent valve 40 is provided.

  The latent heat recovery type auxiliary heater 28 includes a latent heat recovery heat exchanger 28a, a sensible heat recovery heat exchanger 28b, and a latent heat recovery system provided in a shared portion of the hot water supply path 27 with the heat source circulation path 20. A heat exchanger 28a and a sensible heat recovery heat exchanger 28b, a fan 28d for supplying combustion air to the burner 28c, and an inflow temperature of hot water flowing into the latent heat recovery heat exchanger 28a. An inflow temperature sensor (not shown), an outflow temperature sensor (not shown) for detecting the outflow temperature of hot water flowing out from the sensible heat recovery heat exchanger 28b, hot water or heat flowing into the latent heat recovery heat exchanger 28a A flow rate sensor (not shown) for detecting the flow rate of the medium is provided, and the operation of the auxiliary heater 28 is controlled by the operation control unit 5.

The latent heat recovery heat exchanger 28a and the sensible heat recovery heat exchanger 28b are configured such that the combustion exhaust gas flow of the combustion exhaust gas of the burner 28c is in a state where the latent heat recovery heat exchanger 28a is located upstream in the hot water supply passage 27. The latent heat recovery heat exchangers 28a are arranged in the direction along the combustion exhaust gas flow direction in such a manner that the latent heat recovery heat exchangers 28a are located on the downstream side.
Then, in the latent heat recovery heat exchanger 28a, hot water is heated mainly by the latent heat of the combustion exhaust gas of the burner 28c, and in the sensible heat recovery heat exchanger 28b, the latent heat is mainly generated by the sensible heat of the combustion exhaust gas of the burner 28c. It is configured to heat the hot water heated by the recovery heat exchanger 28a.

  The operation control of the auxiliary heater 28 by the operation control unit 5 will be briefly described. The inflow temperature detected by the inflow temperature sensor is the target heating in a state where the flow rate sensor detects a flow rate equal to or higher than a set flow rate. When the temperature is lower than the temperature, the burner 28c is combusted, and the combustion amount of the burner 28c is adjusted so that the outflow temperature detected by the outflow temperature sensor becomes the target heating temperature. When the detected flow rate of the flow sensor becomes less than the set flow rate, the burner 28c is extinguished. Incidentally, the target heating temperature is the target hot water temperature set by the temperature setting unit (not shown) of the remote control operation unit (not shown) of the cogeneration system when the operation of the heat consuming terminal 3 is stopped. When the heat consumption terminal 3 is in operation, it is set to a predetermined temperature set in advance.

The cooling water circulation path 13 is branched into a hot water storage heat exchanger 24 side and a heat source heat exchanger 25 side, and the flow rate of the cooling water to be passed to the hot water storage heat exchanger 24 side and the heat source use are branched at the branch points. A diversion valve 30 is provided that adjusts the ratio of the flow rate of the cooling water that flows to the heat exchanger 25 side.
The diversion valve 30 allows the entire amount of cooling water in the cooling water circulation path 13 to flow to the hot water storage heat exchanger 24 side, or allows the entire amount of cooling water in the cooling water circulation path 13 to flow to the heat source heat exchanger 25 side. It is comprised so that it can also be made.

The hot water storage heat exchanger 24 is configured to heat the hot water flowing through the hot water circulation path 16 by passing the cooling water of the cooling water circulation path 13 that has recovered the heat generated by the fuel cell 1. Yes. In the heat source heat exchanger 25, the hot water for the heat source flowing through the heat source circulation path 20 is heated by passing the cooling water in the cooling water circulation path 13 that has recovered the heat generated by the fuel cell 1. It is configured.
In the heat exchanger 26 for heat medium heating, the heat medium flowing through the heat medium circulation path 22 is passed by flowing hot water for the heat source heated by the heat exchanger 25 for heat source or the auxiliary heater 28. It is configured to be heated. Incidentally, a heating terminal such as a floor heating device, a bathroom heating dryer or a fan convector is provided as the heat consuming terminal 3.

  The hot water supply passage 27 is provided with hot water supply load calorie measuring means 31 for measuring the hot water supply load calorie when supplying hot water to the hot water supply destination, and the terminal load for measuring the terminal load calorie at the heat consuming terminal 3. A calorie measuring means 32 is also provided. In addition, although illustration is abbreviate | omitted, these hot water supply load calorie | heat_amount measurement means 31 and terminal load calorie | heat_amount measurement means 32 are the flow rate which detects the temperature sensor which detects the temperature of the flowing hot water and a heat medium, and the flow volume of a hot water and a heat medium. And a sensor, and is configured to detect the load heat quantity based on the detected temperature of the temperature sensor and the detected flow rate of the flow sensor.

A hot water storage temperature sensor Sh that detects the temperature of hot water that is heated by the hot water storage heat exchanger 24 and supplied to the hot water tank 2 at a location downstream of the hot water storage heat exchanger 24 in the hot water circulation path 16. Is provided.
The hot water tank 2 has an upper end temperature sensor S1 for detecting the temperature of hot water at the upper end of the hot water tank 2, and an equally divided portion obtained by roughly dividing the hot water tank 2 into three equal parts in the vertical direction. Intermediate upper temperature sensor S2 for detecting the temperature of hot water at the upper end portion in the middle layer portion, intermediate lower temperature sensor S3 for detecting the temperature of hot water at the lower end portion in the middle layer portion of the hot water tank 2, and hot water at the lower end of the hot water tank 2 A lower end temperature sensor S4 for detecting the temperature is provided, and a water supply temperature sensor Si for detecting the temperature of the water supplied to the hot water tank 2 is provided in the water supply passage 29.

A method of calculating the amount of stored hot water in the hot water storage tank 2 by the operation control unit 5 will be described.
The temperatures of the hot water in the hot water tank 2 detected by the upper end temperature sensor S1, the intermediate upper temperature sensor S2, the intermediate lower temperature sensor S3, and the lower end temperature sensor S4 are T1, T2, T3, and T4, respectively. The water supply temperature detected by the temperature sensor Si is Ti, and the capacities of the upper layer portion, the middle layer portion, and the lower layer portion are V (liters).
Further, assuming that the weighting coefficient in the upper layer part is A1, the weighting coefficient in the middle layer part is A2, and the weighting coefficient in the lower layer part is A3, the amount of stored hot water (kcal) is calculated by the following (Equation 3). be able to. In this embodiment, the unit of calorie may be indicated by the unit of kcal, but by dividing each value by the coefficient α set to 860 based on the relationship of 1 kWh = 860 kcal, the unit of kWh Can be obtained as

Hot water storage heat amount = (A1 * T1 + (1-A1) * T2-Ti) * V
+ (A2 * T2 + (1-A2) * T3-Ti) * V
+ (A3 * T3 + (1-A3) * T4-Ti) * V (Equation 3)

  The weighting factors A1, A2, A3 are empirical values considering past temperature distribution data in each layer of the hot water tank 2. Here, as A1, A2, A3, for example, A1 = A2 = 0.2 and A3 = 0.5. A1 = A2 = 0.2 indicates that the influence of the temperature T2 is larger than the influence of the temperature T1 in the upper layer portion. This indicates that 80% of the upper layer is close to the temperature T2, and 20% is close to the temperature T1. The same applies to the middle layer portion. In the lower layer part, it shows that the influence of temperature T3 and T4 is the same.

  The operation control unit 5 controls the operation of the fuel cell 1 in a state where the cooling water circulation pump 15 is operated during the operation of the fuel cell 1, and the hot water circulation pump 17 and the heat source circulation pump 21. The hot-medium storage pump 2 stores hot water in the hot-water tank 2 and supplies the heat medium to the heat-consuming terminal 3 by controlling the operation of the heat-medium circulation pump 23, the diversion valve 30 and the heat source intermittent valve 40. It is comprised so that the heat-medium supply operation to perform may be performed.

  The operation control unit 5 performs the hot water storage operation in a state where no operation command is given from a terminal remote controller (not shown) for the heat consuming terminal 3, and in the hot water storage operation, the diversion valve 30 is configured to reduce the total amount of cooling water. The temperature of the hot water supplied to the hot water storage tank 2 is switched to the state of flowing through the hot water storage heat exchanger 24 and the heat source intermittent valve 40 is closed based on the detection information of the hot water storage temperature sensor Sh. Is configured to control the operation of the hot water circulation pump 17 in order to adjust the hot water circulation amount so that the temperature becomes a preset target hot water storage temperature (for example, 60 ° C.). The hot water at the target hot water temperature is stored in the hot water tank 2 by this hot water storage operation.

In addition, when the operation is commanded from the terminal remote controller, the operation control unit 5 performs the heat medium supply operation. In the heat medium supply operation, the heat source intermittent valve 40 is opened, and the heat source circulation pump is operated. In a state in which 21 is operated at a preset rotational speed, the flow dividing valve 30 is configured to allow the coolant corresponding to the terminal load heat amount at the heat consuming terminal 3 to flow through the heat exchanger 25 for heat source. As described above, when the diverter valve 30 is controlled to allow the cooling water to flow also to the hot water storage heat exchanger 24 side in such a state that the heat medium supply operation is performed as described above. The operation of the hot water circulation pump 17 is controlled, and the hot water storage operation is executed in parallel with the heat medium supply operation.
When the operation control unit 5 is instructed to stop the operation from the terminal remote controller during the heat medium supply operation, the operation control unit 5 causes the diverter valve 30 to pass the entire amount of cooling water to the hot water storage heat exchanger 24 side. The heat source intermittent pump 40 is closed, the heat source circulation pump 21 is stopped, and the hot water circulation pump 17 is operated to switch from the heat medium supply operation to the hot water storage operation. It is configured.

  When the hot water in the hot water tank 2 is supplied to the hot water supply destination through the hot water supply passage 27 and during the execution of the heating medium supply operation, the operation control unit 5 supplies the hot water supplied to the auxiliary heater 28. When the temperature of the gas is lower than the target heating temperature, the amount of gas fuel supplied to the burner 28c is adjusted so that hot water supplied to the auxiliary heater 28 is heated to the target heating temperature and discharged. Become.

  Further, the operation control unit 5 stores hot water up to the bottom of the hot water tank 2 when the temperature detected by the lower end temperature sensor S4 is equal to or higher than a preset temperature for heat radiation operation during the hot water storage operation. Assuming that the amount of hot water stored in the tank 2 is full, the three-way valve 18 is switched to a state in which the hot water taken out from the lower part of the hot water tank 2 is circulated so as to pass through the radiator 19 and the radiator 19 is operated. After the hot water taken out from the lower part of the water is radiated by the radiator 19, the hot water is passed through the hot water storage heat exchanger 24, heated, and supplied to the hot water tank 2.

Next, control of the operation of the fuel cell 1 by the operation control unit 5 will be described.
The operation control unit 5 performs time-series predicted load power, time-series predicted load heat amount, and heat generation efficiency of the auxiliary heater 28 at the start point of the operation cycle (corresponding to the periodic operation mode selection timing). Based on the above, the predicted energy consumption during continuous operation when the fuel cell 1 is assumed to be operated continuously and the predicted energy consumption during intermittent operation when the fuel cell 1 is assumed to be operated intermittently are obtained. Based on the obtained predicted energy consumption during continuous operation, predicted energy consumption during intermittent operation, and operation mode selection conditions, the operation mode of the fuel cell 1 is determined as a continuous operation mode, an intermittent operation mode, and the fuel cell 1. The operation mode selection process defined in one of the standby modes for stopping the operation and waiting for the operation is executed.

  And in this embodiment, the operation mode selection condition uses the predicted operation merit for each of the predicted energy consumption during the continuous operation and the predicted energy consumption during the intermittent operation as an operation mode selection index. The conditions are set to determine the operation mode of the fuel cell 1 based on the selection index.

  For example, the operation cycle is set to 1 day, and a plurality of unit times constituting the operation cycle are set to 1 hour. Further, as the predicted operation merit, a predicted energy reduction amount predicted to be obtained by operating the fuel cell 1 is obtained.

The processing for obtaining the time-series predicted load power and the time-series predicted load heat quantity by the operation control unit 5 will be described. By the way, the load heat amount is composed of a hot water supply load heat amount when hot water is supplied to the hot water supply destination and a terminal load heat amount at the heat consuming terminal 3.
The operation control unit 5 stores the actual load power data, the actual hot water supply load heat amount data, and the actual terminal load heat amount data in the memory in association with the operation cycle and the unit time, so that the past time-series load power data and The past time-series load calorie data is configured to be managed in association with each unit time for each operation cycle over a set period (for example, four weeks before the operation day).
Incidentally, the actual load power is measured based on the measured value of the load power measuring means 11 and the output value of the inverter 6, and the actual hot water supply load heat quantity is measured by the hot water supply load heat quantity measuring means 31, and the actual terminal load heat quantity is measured. Is measured by the terminal load calorie measuring means 32.

  And the said operation control part 5 is for continuous prediction based on the management data of the time series past load electric power data and the time series past load calorie | heat amount data at the start time (for example, 3:00 am) of an operation cycle. Time-series predicted load calorie data and time-series predicted load power data of the first operation cycle of the set number of operation cycles (for example, 3 times), and the first of the operation cycles of the set number of times for prediction Time-series predicted load calorie data of the operation cycle subsequent to the operation cycle is obtained by being divided for each unit time. Incidentally, the time-series predicted load heat quantity data is data obtained by adding the time-series predicted hot water supply load heat quantity data and the time-series predicted terminal load heat quantity data, but in this embodiment, the heat load state Will be described on the assumption that the terminal load heat amount is not generated in the heat consuming terminal 3 and only the hot water supply load heat amount is generated.

For example, at the start of the operation cycle, as shown in FIG. 3, the time-series predicted load power data and the time-series predicted hot water supply load heat amount data of the first operation cycle among the operation cycles of the set number of times for prediction are obtained. It is obtained every unit time, and is obtained from predicted hot water supply load calorific value data of an operation cycle (only a part of the second operation cycle is shown in FIG. 3) subsequent to the first operation cycle among the operation cycles of the set number of times for prediction. .
Incidentally, the unit of predicted load power data is kWh, and the unit of predicted hot water supply load heat amount data is kcal / h.

The operation mode of the fuel cell 1 will be described.
The continuous operation mode is a mode in which the fuel cell 1 is continuously operated during the operation cycle, and the intermittent operation mode is a mode in which the fuel cell 1 is operated intermittently during the operation cycle. As modes, a plurality of types of operation modes in which the power output mode of the fuel cell 1 with respect to the predicted load power is made different are included. As the intermittent operation mode, the power output mode of the fuel cell 1 with respect to the predicted load power or the fuel cell 1 A plurality of types of driving modes with different driving time zones are included.

  The plurality of types of continuous operation modes include a load following continuous operation mode in which the power generation output of the fuel cell 1 follows the predicted load power in the entire time period of the operation cycle, and a part of the plurality of unit times of the operation cycle. A suppressed continuous operation mode in which the power generation output of the fuel cell 1 is set to be a set suppression output smaller than the predicted load power in the unit time and the power generation output of the fuel cell 1 follows the predicted load power in the remaining unit time, and The power generation output of the fuel cell 1 is set to a set increase output larger than the predicted load power in a part of the plurality of unit times of the operation cycle, and the power generation output of the fuel cell 1 in the remaining unit time. Is included in the forced continuous operation mode that causes the following load power to follow the predicted load power.

  Further, when the fuel cell 1 is operated in the load follow-up continuous operation mode, the hot water storage tank 2 in the plurality of unit times when the suppression continuous operation mode is set as the set suppression output. Of the unit time before the unit time in which the excess heat state occurs when there is a unit time in which the excess heat state in which the predicted hot water storage amount is equal to or greater than the preset upper limit hot water storage amount in the hot water tank 2 Thus, the unit time when the excess heat state is eliminated and the predicted energy reduction amount is the largest is determined, and the forced continuous operation mode sets the unit time for the set increase output as the load following continuous operation mode. When the fuel cell 1 is operated, a unit time in which a shortage of heat occurs in which the predicted amount of stored hot water in the hot water tank 2 is insufficient with respect to the predicted load heat amount during a plurality of unit times of the operation cycle. When present, of the previous unit time than the unit time the thermal insufficiency occurs, and the predicted energy reductions the thermal insufficiency is resolved is what is provided for in most larger unit time.

The predicted amount of stored hot water in the hot water tank 2 is the amount of heat that is predicted to be stored in the hot water tank 2 as hot water, and the predicted amount of stored hot water (kcal / h) for each unit time is expressed by the following equations 4 and 5. Desired. In each equation, the subscript “n” indicates the order of unit times in the operation cycle. For example, when n = 1, the first unit time in the operation cycle is indicated.
However, the predicted hot water storage amount ₀ as the predicted hot water storage amount _n-1 in Equation 2 when n = 1 is the predicted hot water storage amount at the start of the operation cycle, and is a value obtained based on Equation 3 above. The

Predicted hot water storage amount _n = (Predicted hot water storage amount _n-1 −Predicted load heat amount _n + Predicted heat output _n ) × (1-tank heat dissipation rate) (Equation 4)
Predicted heat output _n = α × {(predicted power output _n ÷ battery power generation efficiency) × battery heat efficiency} + surplus power × α × β-base heat dissipation amount (equation 5)

However,
The tank heat release rate is the heat release rate from the hot water storage tank 2, and is preset to 0.012 and stored in the memory 34, for example.
The battery power generation efficiency indicates the ratio of the power generation output (kWh) to the unit energy consumption (kWh) in the fuel cell 1, and the battery thermal efficiency is the ratio of the generated heat amount (kWh) to the unit energy consumption (kWh) in the fuel cell 1. The battery power generation efficiency and the battery thermal efficiency are set according to the power generation output and stored in the memory 34 as shown in FIG.
In this cogeneration system, the base heat release amount is the amount of heat radiated without being used for hot water storage in the hot water storage tank 2 and heating by the heat consuming terminal 3 out of the generated heat amount of the fuel cell 1. .
The surplus power is obtained by subtracting the predicted load power from the predicted power output when the predicted power output is larger than the predicted load power.
For example, when the predicted load power is smaller than the minimum output of the fuel cell 1, the surplus power is obtained by subtracting the predicted load power from the minimum output of the fuel cell 1. As will be described later, when the power generation output of the fuel cell 1 is set to a set increase output larger than the main output following the predicted load power, the surplus power is obtained by subtracting the predicted load power from the set increase output. Desired. When the predicted load power is smaller than the minimum output of the power generation output adjustment range, the minimum output is the main output, and when the predicted load power is larger than the maximum output of the power generation output adjustment range, the maximum output is power. Main output.
α is a coefficient set to 860 as described above.
β is a heater efficiency that is an efficiency when the electric heater 12 converts surplus power (kWh) into heat (kWh), and is set in advance.

  With the unit time for causing the power generation output of the fuel cell 1 to follow the predicted load power in the plurality of types of intermittent operation modes, the predicted energy reduction amount is the largest among the plurality of unit times of the operation cycle. A plurality of unit times of the operation cycle, wherein the load follow-up intermittent operation mode defined as a unit time to be increased, and the unit time for adjusting the power generation output of the fuel cell 1 to a setting suppression output smaller than the predicted load power are set as the operation time zone. The controlled intermittent operation mode determined at the unit time in which the predicted energy reduction amount is the largest, and the unit time for adjusting the power generation output of the fuel cell 1 to a set increase output larger than the predicted load power is the operation time period. The forced intermittent operation mode defined as the unit time in which the predicted energy reduction amount is the largest among the plurality of unit times of the operation cycle is included.

Further, in the load follow-up intermittent operation mode, the predicted energy reduction amount based on the predicted load power and the predicted load heat amount in the operation cycle that defines the unit time for causing the power generation output of the fuel cell 1 to follow the predicted load power is the largest. A single-cycle-compatible load-following intermittent operation mode that is defined as a unit time that increases, and a unit time that causes the power generation output of the fuel cell 1 to follow the predicted load power are predicted load power and predicted load heat amount in the operation cycle that defines the unit time. In addition, a load follow intermittent operation mode corresponding to a plurality of cycles, which is defined as a unit time in which the predicted energy reduction amount based on the predicted load heat amount in the subsequent operation cycle is the largest, is included.
In the suppression intermittent operation mode, a unit time for adjusting the power generation output of the fuel cell 1 to the set suppression output is a unit in which the predicted energy reduction amount based on the predicted load power and the predicted load heat amount in the operation cycle that determines the unit time is the largest. A single cycle corresponding suppression intermittent operation mode determined in time, and a unit time for adjusting the power generation output of the fuel cell 1 to the set suppression output, the predicted load power and the predicted load heat amount in the operation cycle for determining the unit time, and the subsequent operation And a multi-cycle compatible intermittent intermittent operation mode defined in a unit time in which the predicted energy reduction amount based on the predicted load heat quantity in the cycle is the largest.
In the forced intermittent operation mode, the unit time for adjusting the power generation output of the fuel cell 1 to the set increase output is a unit in which the predicted energy reduction amount based on the predicted load power and the predicted load heat amount in the operation cycle that determines the unit time is the largest. Single cycle-compatible forced intermittent operation mode determined in time, unit time for adjusting the power generation output of the fuel cell 1 to the set increase output, predicted load power and predicted load heat amount in the operation cycle for determining the unit time, and subsequent operation And a forced cycle operation mode corresponding to a plurality of cycles defined in a unit time in which the predicted energy reduction amount based on the predicted load heat amount in the cycle is the largest.

  In this embodiment, since the operation cycle is set to one day, the single cycle correspondence type of each of the load following intermittent operation mode, the suppression intermittent operation mode, and the forced intermittent operation mode is described as a one-day correspondence type. In addition, the load following intermittent operation mode, the suppression intermittent operation mode, and the forced intermittent operation mode, each of which corresponds to a plurality of cycles, is a two-day response type in which the subsequent operation cycle is one time, and a subsequent operation cycle is two times. 3 day compatible type is included.

Hereinafter, the forced continuous operation mode and the setting increase output in each of the forced intermittent operation modes of the 1 day correspondence type, the 2 day correspondence type, and the 3 day correspondence type, and the suppression continuous operation mode and the 1 day correspondence type, 2 A setting suppression output setting method in each of the suppression correspondence intermittent operation modes of the day correspondence type and the three day correspondence type will be described.
As shown in FIG. 5, the temporarily set output for increasing output setting or suppressing output setting is stepwise (for example, 0.25 to 0.75 kW in this embodiment) within the power generation output adjustment range of the fuel cell 1 (for example, , 0.05 kW interval), and for each temporarily set output, when the power generation output of the fuel cell 1 is adjusted to the temporarily set output, the amount of generated heat (kW) generated when the output of the fuel cell 1 is increased is expressed by the following equation: 6, the energy amount difference (kW) for power generation at the time of output suppression, which is the difference in energy consumption between the case where the temporarily set output is obtained by the fuel cell 1 and the case where it is obtained by the commercial power source 7, is expressed by the following equation 7. Thus, the generated heat amount at the time of output increase and the energy amount difference for power generation at the time of output suppression are associated with each temporarily set output and stored in the memory 34.

Amount of heat generated when output increases = (temporary set output ÷ battery power generation efficiency) x battery thermal efficiency (Equation 6)
Difference in energy amount for power generation when output is suppressed = Temporary setting output ÷ Battery power generation efficiency-Temporary setting output ÷ Commercial power generation efficiency ... (Equation 7)
However, the commercial power generation efficiency is the ratio of the power generation output (kWh) to the unit energy consumption (kWh) in the commercial power supply 7.

  Incidentally, since the commercial power generation efficiency is greater than the battery power generation efficiency, the difference in energy amount for power generation during output suppression is obtained as a negative value. Therefore, the smaller the absolute value of the energy amount difference during power suppression during output suppression, the smaller the energy This is advantageous in terms of consumption.

  And the said operation control part 5 sets the thing with the largest calorie | heat amount at the time of an output increase as a setting increase output among temporary setting outputs larger than an electric main output about each unit time of an operation cycle, Among the temporarily set outputs that are smaller, the output absolute value of the difference in energy amount for power generation at the time of output suppression is set as the setting suppression output.

Next, a description will be given of processing for obtaining the predicted energy reduction amount for each of the plurality of types of operation modes by the operation control means 5.
As shown in the following equation 8, the predicted energy reduction amount in each operation mode is the predicted energy consumption amount when the fuel cell 1 is operated in each operation mode from the predicted energy consumption amount when the fuel cell 1 is not operated. Calculate by subtracting.

  Predicted energy reduction amount P = predicted energy consumption amount E1 when the fuel cell 1 is not operated E1-predicted energy consumption amount E2 when the fuel cell 1 is operated (Equation 8)

The predicted energy consumption E1 (kWh) when the fuel cell 1 is not operated is obtained when the predicted load power of the first operation cycle is supplemented with the received power from the commercial power supply 7 as shown in the following formula 9. It is obtained as the sum of the predicted energy consumption in the commercial power supply 7 and the predicted energy consumption when all of the predicted load heat amount in the first operation cycle is supplemented with the heat generated by the auxiliary heater 28.
In other words, the predicted energy consumption E1 in the case where the fuel cell 1 is not operated is obtained in the same manner regardless of the expected energy reduction amount in any operation mode.

  E1 = predicted load power / commercial power generation efficiency + predicted load calorie / R (Equation 9)

However,
The predicted load heat amount is a value converted into kWh.
R is the heat generation efficiency of the auxiliary heater, and is the ratio of the amount of heat generated (kWh or kcal) to the unit energy consumption (kWh or kcal) in the auxiliary heater.
And, as the heat generation efficiency of the auxiliary heater, the heat generation efficiency R2 of the latent heat recovery type auxiliary heater 28 provided in this cogeneration system (hereinafter sometimes referred to as the heat generation efficiency R2 of the latent heat recovery type), The memory 34 stores the heat generation efficiency R1 for selecting the operation mode set to a value lower than the heat generation efficiency R2 of the latent heat recovery type.
Incidentally, in this embodiment, the heat generation efficiency R2 of the auxiliary heater 28 of the latent heat recovery type is set to 0.85, for example, and the heat generation efficiency R1 for selecting the operation mode is the heat generation efficiency of the non-latent heat recovery type auxiliary heater 28 For example, 0.70 is set.

  On the other hand, the predicted energy consumption E2 (kWh) when the fuel cell 1 is operated is calculated by using the predicted load power and the predicted load heat amount in the first operation cycle as the predicted power generation output of the fuel cell 1 and Receiving from the commercial power supply 7 all of the predicted energy consumption of the operation cycle, which is the energy consumed by the fuel cell 1 when supplemented with the predicted heat output, and the predicted insufficient power corresponding to the predicted load power minus the predicted power output. It is obtained by the sum of the predicted energy consumption in the commercial power source 7 when supplemented with electric power and the predicted energy consumption when all of the predicted insufficient heat is supplemented with the heat generated by the auxiliary heater 28.

  E2 = Operating cycle predicted energy consumption + predicted insufficient power amount / commercial power generation efficiency + predicted insufficient heat amount / R (Equation 10)

However, the predicted insufficient heat amount is obtained by subtracting the predicted hot water storage amount for the unit time immediately before the unit time from the predicted load heat amount for the unit time for which the predicted insufficient heat amount is obtained, and is converted into a unit of kWh.
R is the heat generation efficiency of the auxiliary heater similar to Equation 9 above.

  The operation cycle predicted energy consumption is obtained by calculating the predicted energy consumption per unit time for operating the fuel cell 1 in each operation mode according to the following formula 11, and integrating the calculated predicted energy consumption per unit time. To find out.

  Predicted energy consumption = (power generation output ÷ battery power generation efficiency) ......... (Formula 11)

As the predicted energy reduction amount of the load following continuous operation mode, the predicted energy reduction amount Pc1 at the time of low heat generation efficiency is obtained using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater, and the auxiliary heater Using the latent heat recovery type heat generation efficiency R2 as the heat generation efficiency, a predicted energy reduction amount P′c1 at the time of the normal heat generation efficiency is obtained.
In other words, the predicted energy consumption E1 when the fuel cell 1 is not operated is obtained by Equation 9 using the heat generation efficiency R1 for operation mode selection, and according to Equation 10 using the heat generation efficiency R1 for operation mode selection. A predicted energy consumption amount E2 when the fuel cell 1 is operated is obtained, and a predicted energy reduction amount Pc1 at the time of low heat generation efficiency is obtained by Eq.
Further, using the latent heat recovery type heat generation efficiency R2, the predicted energy consumption E1 when the fuel cell 1 is not operated is obtained by Equation 9, and the latent heat recovery type heat generation efficiency R2 is used to obtain the fuel cell by Equation 10. A predicted energy consumption amount E2 when 1 is operated is obtained, and a predicted energy reduction amount P′c1 at the time of normal heat generation efficiency is obtained by Eq.
The predicted energy consumption for each unit time is obtained as the main output by the above formula 11, and the predicted energy consumption for each unit time is obtained by integrating the obtained predicted energy consumption for each unit time. Based on the operation cycle predicted energy consumption amount, a predicted energy consumption amount E2 when the fuel cell 1 is operated is obtained by Expression 10.

The predicted energy reduction amount in the forced continuous operation mode is obtained when there is a heat shortage unit time that becomes a heat shortage state when the fuel cell 1 is operated in the load following continuous operation mode. As the predicted energy reduction amount in the continuous operation mode, the predicted energy reduction amount P′c3 at the normal heat generation efficiency is obtained by using the latent heat recovery type heat generation efficiency R2 as the heat generation efficiency of the auxiliary heater.
That is, one or more selected unit times prior to the heat shortage unit time among the plurality of unit times in the operation cycle (when there are multiple units, the one closest to the start point of the operation cycle) In a form in which a plurality of unit times are set as a forced operation time zone for adjusting the power generation output to the set increase output and a remaining unit time of the operation cycle is set as a main operation time zone for adjusting the power generation output to the main output, All the temporary operation patterns for forced operation are formed by varying the unit time selected as the time zone for forced operation.
Then, for all the temporary operation patterns, using the latent heat recovery type heat generation efficiency R2, the predicted energy consumption E1 when the fuel cell 1 is not operated is obtained by Equation 9, and the latent heat recovery type heat generation efficiency R2 is used. The predicted energy consumption amount E2 when the fuel cell 1 is operated is obtained by the equation 10, and the predicted energy reduction amount is obtained by the equation 8 from the E1 and E2.
Note that the predicted energy consumption per unit time in the forced operation time zone is obtained as an increased output by setting the power generation output according to the above equation 11, and the predicted energy consumption per unit time in the main operation time zone is determined as the power generation output according to the above equation 11. Is calculated as the main output, and the predicted energy consumption for each unit time is integrated to obtain the predicted operation cycle energy consumption.

Then, a temporary operation pattern for forced operation that does not generate a surplus heat unit time and that has the maximum predicted energy reduction amount among all the temporary operation patterns for forced operation does not occur, and the calculated temporary operation pattern is obtained. If the heat shortage unit time does not occur, the temporary operation pattern for forced operation is set to the operation pattern of the forced continuous operation mode, and the predicted energy reduction amount of the temporary operation pattern for forced operation is set to the normal value of the forced continuous operation mode. Obtained as the predicted energy reduction amount P′c3 at the time of heat generation efficiency.
In the temporary operation pattern for forced operation in which the excess heat unit time does not occur and the predicted energy reduction amount is maximum, when the heat shortage unit time still occurs, the above processing is performed until the heat shortage unit time does not occur. Will repeat.

The predicted energy reduction amount in the suppression continuous operation mode is obtained when a unit time of heat surplus exists when the fuel cell 1 is operated in the load following continuous operation mode. As the energy reduction amount, a predicted energy reduction amount P′c2 at the time of normal heat generation efficiency is obtained.
That is, one or more selected units of the unit time before the heat surplus unit time (the one closest to the start point of the operation cycle when there are a plurality of unit times) in the operation cycle are selected or continuous. In the form of a plurality of unit times as a suppression operation time zone for adjusting the power generation output to the set suppression output and a remaining unit time of the operation cycle as a main operation time zone for adjusting the power generation output to the main output, By changing the unit time selected as the suppression operation time zone, all temporary operation patterns for the suppression operation are formed.
Then, for all the temporary operation patterns, using the latent heat recovery type heat generation efficiency R2, the predicted energy consumption E1 when the fuel cell 1 is not operated is obtained by Equation 9, and the latent heat recovery type heat generation efficiency R2 is used. The predicted energy consumption amount E2 when the fuel cell 1 is operated is obtained by the equation 10, and the predicted energy reduction amount is obtained by the equation 8 from the E1 and E2.
Note that the predicted energy consumption per unit time in the suppression operation time zone is obtained as a set suppression output by the above equation 11, and the predicted energy consumption per unit time in the main operation time zone is determined as the power generation output by the above equation 11. Is calculated as the main output, and the predicted energy consumption for each unit time is integrated to obtain the predicted operation cycle energy consumption.

Then, a temporary operation pattern for the suppressed operation that does not cause the heat shortage unit time among all the temporary operation patterns for the suppressed operation and has the maximum predicted energy reduction amount is obtained, and the unit time of the heat surplus in the obtained temporary operation pattern If the tempered operation pattern for the restraint operation does not occur, the tentative operation pattern for the restraint operation is set to the operation pattern of the restraint continuous operation mode, and the predicted energy reduction amount of the tentative operation pattern for the restraint operation is predicted for the normal heating efficiency of the restraint operation mode The energy reduction amount P′c2 is obtained.
In addition, in the temporary operation pattern for the suppression operation in which the heat shortage unit time does not occur and the predicted energy reduction amount is the maximum, when the heat surplus unit time still occurs, the above processing is performed until the heat surplus unit time does not occur. Will repeat.

As the predicted energy reduction amount in the one-day load following intermittent operation mode, the predicted energy reduction amount Pi1 at the time of low heat generation efficiency is obtained by using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater.
That is, among the plurality of unit times of the operation cycle, the selected one or a plurality of continuous unit times are set as unit times constituting the operation time zone, and the remaining unit time of the operation cycle is stopped. By changing the unit time selected as the unit time constituting the operation time zone in the form of the unit time constituting the stop time zone, all temporary operation patterns are formed, and among the temporary operation patterns All temporary operation patterns except for a pattern in which the entire unit time of the operation cycle is an operation time zone are stored in the memory 34 as temporary operation patterns for one-day type intermittent operation.

  That is, as a pattern for starting operation from the first unit time, a pattern having the first unit time as an operation time zone, a pattern having first and second unit times as an operation time zone, There are 23 types of patterns in which the third unit time is used as an operating time zone: patterns in which the first to 23rd unit times are used as operating time zones. In addition, as a pattern for starting operation from the second unit time, a pattern using the second unit time as an operation time zone, a pattern using the second and third unit times as an operation time zone, etc. There are 23 types of patterns in which the second to 24th unit time is an operation time zone. As described above, there are 299 types of temporary operation patterns for one-day intermittent operation up to a pattern in which the last 24th unit time of the operation cycle is an operation time zone.

It is assumed that the fuel cell 1 is operated in a state where the power generation output is adjusted to the main output in the operation time zone set in each temporary operation pattern for each of the temporary operation patterns for all the one-day intermittent operation. The predicted energy consumption E1 when the fuel cell 1 is not operated is obtained by Equation 9 using the heat generation efficiency R1 for operation mode selection, and the heat generation efficiency R1 for operation mode selection is obtained by Equation 10 A predicted energy consumption amount E2 when the fuel cell 1 is operated is obtained, and a predicted energy reduction amount P is obtained from the E1 and E2 by Equation 8, and further, a predicted heat output is obtained for each unit time of the first operation cycle. Calculate the predicted amount of stored hot water.
Note that the predicted energy consumption of unit time included in the operation time zone is obtained by using the power generation output as the main output by the above equation 11, and the predicted energy consumption amount of unit time not included in the operation time zone is set to 0. The predicted energy consumption amount is obtained by integrating the predicted energy consumption amount.
Further, the predicted heat output of unit time not included in the operation time zone is 0, and the predicted hot water storage amount of unit time not included in the operation time zone is obtained by setting the predicted heat output _n to 0 according to the above equation 4.

  Then, the temporary operation pattern for the intermittent operation having the maximum predicted energy reduction amount is obtained from all the temporary operation patterns for the daily operation type intermittent operation, and the temporary operation pattern for the intermittent operation is determined as the daily operation type. The operation pattern of the load following intermittent operation mode is set, and the predicted energy reduction amount of the temporary operation pattern for the intermittent operation is obtained as the predicted energy reduction amount Pi1 at the time of low heat generation in the one day type load following intermittent operation mode.

As the predicted energy reduction amount of the two-day load follow-up intermittent operation mode, the predicted energy reduction amount Pi4 at the time of low heat generation efficiency is obtained by using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater.
That is, among all the temporary operation patterns obtained by adding all of the temporary operation patterns for the daily operation type intermittent operation to the temporary operation pattern in which all the unit time of the operation cycle is the operation time zone, as described above. When the power generation output is adjusted to the main output in step 1, the temporary operation pattern in which the predicted hot water storage heat amount in the final unit time in the first operation cycle is larger than 0 is selected as the two-day correspondence temporary operation pattern.
Then, for all the two-day tentative operation patterns, assuming that the predicted hot water storage amount of the last unit time of the first operation cycle is used as the predicted load heat amount of the second operation cycle, a plurality of second operation cycles For each unit time, a predicted heat usage amount used as a predicted hot water storage amount and a predicted load heat amount is obtained.
The predicted amount of stored hot water for each unit time is obtained by _assuming the predicted heat output _n as 0 according to the above equation 4.
Further, the predicted amount of heat used for each unit time is obtained by the following equations 12 to 14.

Predicted hot water storage _n-1 ≥ predicted load heat _{n n}
Predicted heat consumption _n = Predictive load heat quantity _n ... (Equation 12)
Predicted hot water storage amount _n-1 <predicted load heat amount _n
Predicted heat consumption _n = Predicted hot water storage amount _n-1 (Equation 13)
When the predicted amount of stored hot water _n-1 = 0,
Predicted heat consumption _n = 0 ... (Equation 14)

For each of the two-day tentative temporary operation patterns, the predicted use heat amount (converted into kWh) in the second operation cycle is converted into the predicted energy reduction amount of the one-day responsive load follow-up intermittent operation mode obtained as described above. The predicted energy reduction amount is calculated by adding the predicted energy consumption (total predicted utilization heat amount / R1) in the case of supplementing the total of the generated heat with the generated heat of the auxiliary heater 28, and the calculated predicted energy reduction amount is 2 The energy reduction amount per operation cycle (one day) divided by is used as the predicted energy reduction amount of the 2-day correspondence type temporary operation pattern.
Then, among all the two-day type temporary operation patterns, the two-day type temporary operation pattern having the maximum predicted energy reduction amount is set as the operation pattern of the two-day type load follow-up intermittent operation mode, The predicted energy reduction amount of the 2-day correspondence type temporary operation pattern is obtained as the predicted energy reduction amount Pi4 at the time of low heat generation efficiency in the 2-day correspondence type load follow-up intermittent operation mode.

FIG. 3 shows an example of a temporary operation pattern in which the fifth to 23th unit time is an operation time zone, and uses a temporary operation pattern for one-day type intermittent operation. When obtaining the predicted energy reduction amount, the result of obtaining the predicted heat output and the predicted hot water storage amount for each unit time of the first operation cycle and the predicted energy reduction amount of the load following intermittent operation corresponding to the two-day operation are obtained. The result of having calculated | required predicted hot water storage amount and prediction utilization heat amount about each unit time of the 2nd driving | operation period is shown.
However, the portion of the column in which the operation cycle is “first” in FIG. 3 (that is, the portion of the upper table in FIG. 3) is the predicted heat output when obtaining the predicted energy reduction amount of the one-day type load following intermittent operation. And the calculation result of predicted hot water storage amount is shown. Also, the portion of the column in which the operation cycle in FIG. 3 is “second time” (that is, the portion of the lower table in FIG. 3) is the prediction when the predicted energy reduction amount of the 2-day correspondence type load following intermittent operation is obtained. The calculation results of the amount of stored hot water and the predicted amount of heat used are shown.

As the predicted energy reduction amount of the three-day load follow-up intermittent operation mode, the predicted energy reduction amount Pi7 at the time of low heat generation efficiency is obtained by using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater.
That is, out of all the two-day provisional operation patterns, the temporary operation pattern in which the predicted hot water storage heat amount in the final unit time in the second operation cycle is larger than 0 is selected as the three-day correspondence temporary operation pattern, For all the three-day provisional operation patterns, assuming that the predicted hot water storage amount of the last unit time of the second operation cycle is used as the predicted load heat amount of the third operation cycle, Similarly to the above, the predicted amount of stored hot water and the predicted amount of heat used are obtained for each of a plurality of unit times in the third operation cycle.

For each of the three-day tentative temporary operation patterns, the predicted energy consumption in the second and third operation cycles (to the predicted energy reduction amount of the one-day responsive load following intermittent operation mode obtained as described above) ( The predicted energy reduction amount is obtained by adding the predicted energy consumption amount (total of the predicted use heat amount / R1) in the case where the total of the kWh is supplemented with the heat generated by the auxiliary heater 28, and the calculated predicted energy reduction amount The amount obtained by dividing the amount by 3 to obtain the energy reduction amount per one operation cycle (one day) is taken as the predicted energy reduction amount of the temporary operation pattern corresponding to the three days.
Then, among all the three-day provisional operation patterns, the three-day correspondence type temporary operation pattern having the maximum predicted energy reduction amount is set as the operation pattern of the three-day correspondence type load follow-up intermittent operation mode. The predicted energy reduction amount of the 3-day correspondence type temporary operation pattern is obtained as the predicted energy reduction amount Pi7 at the time of low heat generation efficiency in the 3-day correspondence type load follow-up intermittent operation mode.

As the predicted energy reduction amount of the one-day type forced intermittent operation mode, the predicted energy reduction amount Pi3 at the time of low heat generation efficiency is obtained by using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater.
That is, the fuel cell 1 is operated in a state in which the power generation output is adjusted to the set increase output in the operation time zone set in each temporary operation pattern for each of the temporary operation patterns for the continuous operation of the one-day correspondence type. Assuming that, the predicted energy consumption E1 when the fuel cell 1 is not operated is obtained by Equation 9 using the heat generation efficiency R1 for selecting the operation mode, and using the heat generation efficiency R1 for selecting the operation mode, the equation 10, the predicted energy consumption amount E2 when the fuel cell 1 is operated is obtained, the predicted energy reduction amount P is obtained from the E1 and E2 by the equation 8, and the prediction is made for each unit time of the first operation cycle. Obtain heat output and predicted hot water storage.
Note that the predicted energy consumption per unit time included in the operation time zone is obtained by setting the power generation output as a set increase output according to the above equation 11, and the predicted energy consumption per unit time not included in the operation time zone is set to 0. The predicted energy consumption amount is obtained by integrating the predicted energy consumption amount.

  Then, the temporary operation pattern for the intermittent operation having the maximum predicted energy reduction amount is obtained from all the temporary operation patterns for the daily operation type intermittent operation, and the temporary operation pattern for the intermittent operation is determined as the daily operation type. The operation pattern of the forced intermittent operation mode is set, and the predicted energy reduction amount of the temporary operation pattern for the intermittent operation is obtained as the predicted energy reduction amount Pi3 at the time of low heat generation efficiency in the one-day type forced intermittent operation mode.

The operation pattern and the predicted energy reduction amount of the two-day type forced intermittent operation mode are obtained by the same procedure as the procedure for obtaining the operation pattern and the predicted energy reduction amount of the two-day type load follow-up intermittent operation mode, and Since the operation pattern and the predicted energy reduction amount of the three-day compatible forced intermittent operation mode are obtained in the same procedure as the procedure for calculating the operation pattern and the predicted energy reduction amount of the three-day corresponding load follow-up intermittent operation mode. Description of the operation pattern and the predicted energy reduction amount of the 2-day type forced intermittent operation mode, and the procedure for obtaining the operation pattern and the predicted energy reduction amount of the 3-day type forced intermittent operation mode will be omitted.
That is, as the predicted energy reduction amount of the two-day type forced intermittent operation mode, the predicted energy reduction amount Pi6 at the time of low heat generation efficiency is obtained by using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater. As the predicted energy reduction amount of the three-day type forced intermittent operation mode, the predicted energy reduction amount Pi9 at the time of low heat generation efficiency is obtained by using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater.

As the predicted energy reduction amount of the one day correspondence type suppression intermittent operation mode, the predicted energy reduction amount Pi2 at the time of low heat generation efficiency is obtained by using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater.
That is, when the fuel cell 1 is operated in a state where the power generation output is adjusted to the set suppression output in the operation time zone set in each temporary operation pattern for each of the temporary operation patterns for all day-to-day intermittent operation. Assuming that the predicted energy consumption E1 when the fuel cell 1 is not operated is obtained by Equation 9 using the heat generation efficiency R1 for selecting the operation mode, and using the heat generation efficiency R1 for selecting the operation mode, Equation 10 Thus, the predicted energy consumption amount E2 when the fuel cell 1 is operated is obtained, and the predicted energy reduction amount P is obtained from the E1 and E2 by the equation 8, and the predicted heat is calculated for each unit time of the first operation cycle. Obtain the output and predicted hot water storage.
Note that the predicted energy consumption of unit time included in the operation time zone is obtained by setting the power generation output as a setting suppression output by the above formula 11, and the predicted energy consumption amount of unit time not included in the operation time zone is set to 0. The predicted energy consumption amount is obtained by integrating the predicted energy consumption amount.

  Then, the temporary operation pattern for the intermittent operation having the maximum predicted energy reduction amount is obtained from all the temporary operation patterns for the daily operation type intermittent operation, and the temporary operation pattern for the intermittent operation is determined as the daily operation type. The operation pattern of the suppression intermittent operation mode is set, and the predicted energy reduction amount of the temporary operation pattern for the intermittent operation is obtained as the predicted energy reduction amount Pi2 at the time of low heat generation efficiency in the one day correspondence type suppression intermittent operation mode.

The operation pattern and the predicted energy reduction amount of the two-day correspondence type intermittent intermittent operation mode are obtained by the same procedure as the procedure for obtaining the operation pattern and the predicted energy reduction amount of the two-day type load follow-up intermittent operation mode, and Since the operation pattern and the predicted energy reduction amount of the 3-day response type intermittent intermittent operation mode are obtained in the same procedure as the procedure for obtaining the operation pattern and the predicted energy reduction amount of the 3-day response type load following intermittent operation mode. The description of the operation pattern and the predicted energy reduction amount of the two-day response type intermittent intermittent operation mode and the procedure for obtaining the operation pattern and the predicted energy reduction amount of the three-day type suppression intermittent operation mode are omitted.
That is, as the predicted energy reduction amount of the two-day-type suppression intermittent operation mode, the predicted energy reduction amount Pi5 at the time of low heat generation efficiency is obtained by using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater. As the predicted energy reduction amount of the three-day-type suppression intermittent operation mode, the predicted energy reduction amount Pi8 at the time of low heat generation efficiency is obtained by using the heat generation efficiency R1 for operation mode selection as the heat generation efficiency of the auxiliary heater.

By the way, even if the fuel cell 1 is stopped, energy (electric power) is consumed, for example, to keep it in a state where power generation is possible, and the fuel cell 1 in all time zones within the operation cycle. The energy consumed in the cogeneration system when the power is stopped is determined as the standby energy consumption Z in advance through experiments or the like.
The predicted energy consumption when it is assumed that the fuel cell 1 is operated in each of the above operation modes becomes larger than the predicted energy consumption when the fuel cell 1 is not operated, and the predicted energy reduction amount in each operation mode is negative. May be obtained as the value of.
Then, when the predicted energy reduction amount of each operation mode is obtained as a negative value, when the predicted energy reduction amount obtained as the negative value is smaller than the negative value of the standby energy consumption Z, It is possible to use the standby energy consumption Z as a merit of the standby operation because it is more energy saving to make the fuel cell 1 stand by than to operate the fuel cell 1 in any of the above operation modes.
Therefore, standby energy consumption Z is stored in the memory 34 of the operation control unit 5 as a merit of the standby mode.

Next, an explanation will be given for the operation mode selection process for determining the operation mode of the fuel cell 1.
In the first embodiment, when the operation mode selection condition is that the predicted energy reduction amount in the continuous operation mode is equal to or greater than the set reduction amount G (for example, 580 Wh), the operation mode of the fuel cell 1 is given priority over the intermittent operation mode. If the predicted energy reduction amount in the continuous operation mode is smaller than the set reduction amount G, at least one of the predicted energy reduction amount in the continuous operation mode and the predicted energy reduction amount in the intermittent operation mode is on standby. If the negative value “−Z” of the hourly consumption energy Z is greater than or equal to the predicted energy reduction amount in the continuous operation mode and the predicted energy reduction amount in the intermittent operation mode, the operation of the fuel cell 1 is larger. If the form is determined and both the predicted energy reduction amount of the continuous operation mode and the predicted energy reduction amount of the intermittent operation mode are smaller than the negative value “−Z” of the standby energy consumption Z, The operating configuration of the fuel cell 1 is set to the conditions laid down in the standby mode.

Hereinafter, based on the flowchart shown in FIG. 6, the control operation of the operation control unit 5 in the operation mode selection process will be described.
The operation control unit 5 executes the predicted load data calculation process every time when the operation cycle starts (for example, 3:00 am), and performs time-series predicted load power data and time-series predicted load. The amount of heat data is obtained, and then the predicted energy reduction amount calculation process is executed to obtain the predicted energy reduction amount for each of the plurality of operation modes (steps # 1 to # 3).

In the predicted energy reduction amount calculation processing, when it is assumed that the load following continuous operation mode is performed, if there is a surplus unit time in the operation cycle, the predicted energy reduction amount Pc1 when the heat generation efficiency is low for the load following continuous operation mode. In addition, the predicted energy reduction amount P′c1 at the time of normal heat generation efficiency is obtained, the predicted energy reduction amount P′c2 at the time of normal heat generation efficiency is obtained for the suppressed continuous operation mode, and further, the prediction at the time of normal heat generation efficiency in the forced continuous operation mode is obtained. The energy reduction amount P′c3 is set to the set value F for checking.
When it is assumed that the load following continuous operation mode is performed, if there is a heat shortage unit time in the operation cycle, the predicted energy reduction amount Pc1 at the time of low heat generation efficiency and the predicted energy at the time of normal heat generation efficiency for the load tracking continuous operation mode The reduction amount P′c1 is obtained, the predicted energy reduction amount P′c3 at the time of normal heat generation efficiency is obtained for the forced continuous operation mode, and the predicted energy reduction amount P′c2 at the time of normal heat generation efficiency of the suppression continuous operation mode is further calculated. Set to set value F.
When it is assumed that the load following continuous operation mode is performed, if neither the excess heat unit time nor the insufficient heat unit time exists in the operation cycle, the predicted energy reduction amount Pc1 at the time of low heat generation efficiency and the normal for the load following continuous operation mode A predicted energy reduction amount P′c1 at the time of heat generation efficiency is obtained, and further, a predicted energy reduction amount P′c2 at the time of normal heat generation efficiency in the suppressed continuous operation mode and a predicted energy reduction amount P ′ at the time of normal heat generation efficiency in the forced continuous operation mode. Each of c3 is set to the set value F.

  Incidentally, the set value F is set to be smaller than the minimum value of values predicted to be obtained for each of the continuous operation modes of load following, suppression, and intermittent corresponding to various predicted load power and predicted thermal load. It is. If it is predicted that the minimum value is obtained as a negative value, the set value F is set to a negative value having an absolute value larger than the minimum value.

  Furthermore, the predicted energy reduction amounts Pi1, Pi2, and Pi3 when the heat generation efficiency is low, respectively, for the one-day type load follow-up intermittent operation mode, the one-day type suppression intermittent operation mode, and the one-day type forced intermittent operation mode, respectively. For the two-day load following intermittent operation mode, the two-day suppression intermittent operation mode, and the two-day forced intermittent operation mode, respectively, the predicted energy reduction amount Pi4, Pi5 at the time of low heat generation efficiency, respectively, Pi6 is obtained, and the predicted energy reduction amount Pi7 at the time of low heat generation efficiency is obtained for the load follow intermittent operation mode for three days, the suppressed intermittent operation mode for three days, and the forced intermittent operation mode for three days. , Pi8, Pi9.

  Subsequently, in step # 4, it is determined whether or not the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is equal to or larger than the set reduction amount G. Among the load following continuous operation mode, the suppressed continuous operation mode, and the forced continuous operation mode, the operation mode in which the predicted energy reduction amount P′c1, P′c2, and P′c3 during the normal heat generation efficiency is the maximum is the operation mode of the fuel cell 1. (Step # 5).

  When it is determined in step # 4 that the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is smaller than the set reduction amount G, in step # 6, the hot water storage heat amount at the start of the operation cycle is set. The heat load coverage rate U / L indicating the extent to which the predicted hot water supply load heat amount of the operation cycle can be covered is obtained, and in step # 7, the obtained heat load coverage rate U / L is compared with the lower set value K, When the thermal load coverage rate U / L is greater than the lower set value K, it is determined that the standby condition is satisfied, and when the thermal load coverage rate U / L is equal to or lower than the lower set value K, it is determined that the standby condition is not satisfied. To do.

Incidentally, L of the thermal load coverage ratio U / L is the predicted hot water supply load heat amount of the operation cycle obtained by summing the predicted hot water supply load heat amount of each unit time of the first operation cycle.
Further, U of the thermal load cover rate U / L can be covered by the amount of stored hot water at the start of the first operation cycle out of the predicted hot water supply load heat amount of the first operation cycle, assuming the predicted output heat amount of the fuel cell 1 as 0. This is the predicted amount of heat used in the predicted operation cycle.
That is, assuming that the hot water storage amount at the start of the first operation cycle is used as the predicted load heat amount of the operation cycle, the predicted hot water storage amount and the predicted use heat amount are obtained for each of a plurality of unit times of the operation cycle. By summing the predicted usage heat amounts, the predicted usage heat amount U of the operation cycle is obtained.
The lower set value K is set to 0.4, for example.

  When it is determined in step # 7 that the standby condition is not satisfied, in step # 8, the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode and the one day correspondence type load follow intermittent operation mode. Compared with the predicted energy reduction amount Pi1 at the time of low heat generation efficiency, the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is greater than or equal to the predicted energy reduction amount Pi1 at the time of low heat generation efficiency in the load tracking intermittent operation mode. In step # 9, the predicted energy reduction amount P′c1 at the time of normal heat generation efficiency in the load following continuous operation mode, the predicted energy reduction amount P′c2 at the time of normal heat generation efficiency in the suppression continuous operation mode, and the forced continuous operation The predicted energy reduction amount at the maximum normal heat generation efficiency among the predicted energy reduction amounts P′c3 at the normal heat generation efficiency of the configuration is greater than or equal to the negative value “−Z” of the standby energy consumption Z In the above case, the continuous operation mode having the maximum predicted energy reduction amount at the normal heat generation efficiency is determined as the operation mode of the fuel cell 1 (step # 5), and the predicted energy at the maximum normal heat generation efficiency is determined. When the reduction amount is smaller than the negative value “−Z” of standby energy consumption Z, the standby mode is determined as the operation mode of the fuel cell 1 (step # 12).

  When it is determined in step # 8 that the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is smaller than the predicted energy reduction amount Pi1 at the time of low heat generation efficiency in the one day type load follow-up intermittent operation mode 1-day type load follow-up intermittent operation mode, 1-day type suppression intermittent operation mode, 1-day type forced intermittent operation mode, 2-day type load-following intermittent operation mode, 2-day type suppression 9 types of intermittent operation modes: intermittent operation mode, 2-day compatible forced intermittent operation mode, 3-day load follow-up intermittent operation mode, 3-day compatible suppression intermittent operation mode, and 3-day compatible forced intermittent operation mode The predicted energy reduction amount Pi1, Pi2, Pi3, Pi4, Pi5, Pi6, Pi7, Pi8, and Pi9 at the time of the low heat generation efficiency of the form is the maximum predicted energy reduction amount at the time of low heat generation efficiency of the standby energy consumption Z Is equal to or greater than “−Z”, the intermittent operation mode in which the predicted energy reduction amount at the time of the low heat generation efficiency is the maximum is determined as the operation mode of the fuel cell 1 (steps # 10 and 11). When the predicted energy reduction amount is smaller than the negative value “−Z” of the standby energy consumption Z, the standby mode is determined as the operation mode of the fuel cell 1 (step # 12).

  If it is determined in step # 7 that the standby condition is satisfied, it is determined in step # 13 whether or not the fuel cell 1 is in operation. If it is in operation, in step # 14, the thermal load coverage rate U is determined. When it is determined whether / L is larger than the upper set value M (for example, 0.9) that is larger than the lower set value K and not larger, in step # 15, the operation of the fuel cell 1 is performed. It is determined whether or not the operation continuation condition for continuing is satisfied.

  That is, all the temporary operation patterns that are assumed to be the operation time zone from the temporary operation patterns stored in the memory 34, which continues from the start time and is composed of unit times of 1 to the set number N2 (for example, 10). For each of the patterns, assuming that the power generation output is adjusted to the main output during the operation time period, it is determined whether or not the amount of stored hot water in the final unit time in the first operation cycle is 0, and the amount of stored hot water becomes 0. When the temporary operation pattern exists, it is possible to continue the operation of the fuel cell 1 with the hot water in the hot water tank 2 used up, and it is determined that the operation continuation condition is satisfied, and the temporary operation in which the amount of stored hot water becomes 0 When the pattern does not exist, it is determined that the operation continuation condition is not satisfied.

  If it is determined in step # 15 that the operation continuation condition is satisfied, in step # 16, the operation of the fuel cell 1 is set to the load following operation continuation mode in which the operation is continued in the load following operation. In step # 17, the operation continuation is performed. The operation duration setting process for setting the time is executed.

In the operation continuation time setting process, the temporary operation pattern in which the predicted energy reduction amount P is the maximum among the temporary operation patterns determined in step # 15 that the amount of stored hot water in the last unit time in the first operation cycle becomes zero. Set the operation time zone to the operation continuation time.
That is, the predicted energy consumption E2 when the fuel cell 1 is operated for each of the temporary operation patterns determined in step # 14 that the amount of stored hot water in the final unit time in the first operation cycle becomes 0 is expressed by the above equation 10. Then, by substituting the calculated predicted energy consumption E2 and the predicted energy consumption E1 obtained when the fuel cell 1 is not operated according to the equation 9 into the equation 8, the estimated energy reduction amount P is obtained and determined. The operation time zone of the temporary operation pattern having the maximum predicted energy reduction amount P is set as the operation continuation time.

  When it is determined in step # 13 that the fuel cell 1 is stopped, in step # 14, when it is determined that the thermal load coverage ratio U / L is larger than the upper set value M, in step # 15 If it is determined that the operation continuation condition is not satisfied, the standby mode is set at step # 12.

The operation control means 5 operates the fuel cell 1 in the operation mode determined in the operation mode selection process.
That is, when the operation mode of the fuel cell 1 is set to the load following continuous operation mode, the current load power following operation that causes the power generation output of the fuel cell 1 to follow the current load power currently requested over the entire time period of the operation cycle. Execute.
In the current load power follow-up operation, the main load output is obtained for every relatively short predetermined output adjustment period such as one minute, and continuously follows the current load power within the range from the minimum output to the maximum output. And the power generation output of the fuel cell 1 is adjusted to the determined main output.
The current load power is measured based on the measured value of the load power measuring means 11 and the output value of the inverter 6, and the current load power is measured at a predetermined sampling time (for example, in the previous output adjustment cycle). 5 seconds) is obtained as an average value of the data sampled.

When the operation mode of the fuel cell 1 is set to the suppression continuous operation mode, the power generation output of the fuel cell 1 is adjusted to the setting suppression output in the unit time determined to set the power generation output of the fuel cell 1 to the setting suppression output, Current load power follow-up operation is executed in other unit times.
When the operation mode of the fuel cell 1 is set to the forced continuous operation mode, the power generation output of the fuel cell 1 is adjusted to the set increase output in a unit time determined to set the power generation output of the fuel cell 1 to the set increase output, Current load power follow-up operation is executed in other unit times.

When the operation mode of the fuel cell 1 is determined to be any one of the load follow-up intermittent operation of the one-day correspondence type, two-day correspondence type, and three-day correspondence type, the current load power follow-up operation is performed in the unit time included in the operation time zone. The fuel cell 1 is stopped during the unit time included in the stop time zone.
When the operation mode of the fuel cell 1 is determined to be any one of the one-day correspondence type, two-day correspondence type, and three-day correspondence type intermittent intermittent operation, the setting suppression output is set in the unit time included in the operation time zone. In the unit time, the power generation output of the fuel cell 1 is adjusted to the set suppression output, and the fuel cell 1 is stopped in the unit time included in the stop time zone.
When the operation mode of the fuel cell 1 is determined to be any one of the one-day type, two-day type, and three-day type forced intermittent operation, the set increase output is set in the unit time included in the operation time zone. In a certain unit time, the power generation output of the fuel cell 1 is adjusted to the set increase output, and the fuel cell 1 is stopped in the unit time included in the stop time zone.

  That is, every time the operation cycle starts, the operation mode selection process is executed. In the operation mode selection process, as described above, the thermal load coverage ratio U / L is larger than the lower set value K and the standby condition is satisfied. When it is determined that the fuel cell 1 is stopped, when it is determined that the fuel cell 1 is stopped, when it is determined that the fuel cell 1 is in operation and the thermal load coverage ratio U / L is greater than the upper set value M, and In any case where it is determined that the fuel cell 1 is in operation and the thermal load coverage ratio U / L is equal to or lower than the upper set value M and does not satisfy the operation continuation condition, the standby mode is set. Therefore, in the previous driving mode selection process, the two-day type or the three-day type load follow, suppression, or forced intermittent driving mode is set, and the current driving mode selection process is performed at 2 points. For day-to-day or 3-day type intermittent operation If the standby mode is set as described above in the operation mode selection process at the time corresponding to the start point of the second operation cycle, 2 in the 2-day correspondence type or the 3-day correspondence type intermittent operation mode. The fuel cell 1 is stopped over the entire time period of the second operation cycle, and the 2-day correspondence type or the 3-day correspondence type intermittent operation mode is continued.

  In the 2-day or 3-day intermittent operation mode, the actual hot water supply load heat amount in the first operation cycle is larger than the predicted hot-water supply load heat amount, or in the 3-day type intermittent operation mode. When it is determined that the actual hot water supply load heat amount in the second operation cycle is larger than the predicted hot water supply load heat amount and the heat load coverage rate U / L is equal to or lower than the lower set value K, the standby condition is not satisfied. , It will be determined in any intermittent operation mode.

  As described above, in the operation mode selection process, the predicted energy reduction amount Pc1 for the predicted energy consumption of the load following continuous operation mode obtained using the heat generation efficiency R1 for operation mode selection, and the operation mode selection Based on the predicted energy reduction amount Pi1 for the predicted energy consumption amount of the load following intermittent operation mode obtained using the heat generation efficiency R1, the operation mode of the fuel cell 1 is determined to be either the continuous operation mode or the intermittent operation mode. Therefore, the operation control unit 5 sets the heat generation efficiency of the auxiliary heater 28 to a value lower than the heat generation efficiency of the latent heat recovery type auxiliary heater 28 in the operation mode selection process. Using the heat generation efficiency for selecting the operation mode, the predicted energy consumption during the continuous operation and the predicted energy consumption during the intermittent operation are obtained. It would have been.

  Further, when the operation mode of the fuel cell 1 is set to the continuous operation mode, among the load following continuous operation mode, the suppression continuous operation mode and the forced continuous operation mode, the predicted energy reduction amount P′c1, at the time of normal heat generation efficiency Since P′c2 and P′c3 are configured so as to determine the continuous operation mode having the maximum value as the operation mode of the fuel cell 1, the operation control unit 5 performs the operation mode of the fuel cell 1 in the operation mode selection process. When the fuel cell 1 is operated in the continuous operation mode with different power generation outputs, the heat generation efficiency of the latent heat recovery type auxiliary heater 28 is used for each of the cases where the fuel cell 1 is operated in the continuous operation mode. The predicted energy consumption during the continuous operation is obtained, and the power generation output with a small predicted energy consumption is determined as the power generation output of the fuel cell 1.

  Furthermore, when the operation mode of the fuel cell 1 is determined to be the intermittent operation mode, the load tracking intermittent operation mode for one day type, the suppression intermittent operation mode for one day type, the forced intermittent operation mode for one day type, 2-day compatible load-following intermittent operation configuration, 2-day-controlled suppression intermittent operation configuration, 2-day compatible forced intermittent operation configuration, 3-day compatible load-following intermittent operation configuration, 3-day compatible suppression intermittent operation configuration Fuel cell 1 is the intermittent operation mode in which the predicted energy reduction amount Pi1, Pi2, Pi3, Pi4, Pi5, Pi6, Pi7, Pi8, Pi9 is the largest among the three-day type forced intermittent operation modes. Therefore, when the operation control unit 5 determines that the operation mode of the fuel cell 1 is the intermittent operation mode in the operation mode selection process, the operation time zone is changed. The fuel power For each of the cases in which 1 is operated in the intermittent operation mode, the predicted energy consumption amount during the intermittent operation is obtained using the heat generation efficiency for selecting the operation mode, and an operation time period in which the predicted energy consumption amount is small is obtained. The fuel cell 1 is configured to be determined in the operation time zone.

  Hereinafter, the second and third embodiments of the present invention will be described. Each of the second and third embodiments describes another embodiment of the operation mode selection process, and is a cogeneration system. Since the overall configuration is the same as that of the first embodiment, the description of the overall configuration of the cogeneration system is omitted, and the control operation in the operation mode selection process of the operation control unit 5 will be mainly described.

[Second Embodiment]
Hereinafter, a second embodiment of the present invention will be described.
This 2nd Embodiment demonstrates another embodiment about the said driving | running | working mode selection conditions, and since a predicted load data calculation process and a predicted energy reduction amount calculation process are the same as said 1st Embodiment. Description of the predicted load data calculation process and the predicted energy reduction amount calculation process will be omitted.
In this second embodiment, the operation mode selection condition is that the predicted operation merits for the predicted energy consumption during the continuous operation and the predicted energy consumption during the intermittent operation are used as the operation mode selection index. It is the same as the first embodiment in that it is set to a condition that determines the operation mode of the fuel cell 1 based on the selection index. However, the operation mode selection condition is a predicted energy reduction of the continuous operation mode. When the amount and the predicted energy reduction amount of the intermittent operation mode are smaller than the negative value “−Z” of the standby energy consumption Z, the operation mode of the fuel cell 1 is set to the standby mode, and the predicted energy reduction amount of the continuous operation mode is determined. When at least one of the predicted energy reduction amounts of the intermittent operation mode is equal to or greater than the negative value “−Z” of the standby energy consumption Z, the predicted error of the continuous operation mode and the intermittent operation mode is determined. The operating configuration towards conservation reduction is greater in that they are set to the condition for determining the operation mode of the fuel cell 1, different from the first embodiment.

Hereinafter, based on the flowchart shown in FIG. 7, the control operation of the operation control unit 5 in the operation mode selection process will be described.
Every time when the operation cycle starts, as in the first embodiment, the predicted load data calculation process is executed to obtain time-series predicted load power data and time-series predicted load heat quantity data, Subsequently, a predicted energy reduction amount calculation process is executed to obtain a predicted energy reduction amount for each of the plurality of types of operation modes (steps # 21 to 23).

  Subsequently, at step # 24, the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is equal to or larger than the predicted energy reduction amount Pi1 at the time of low heat generation efficiency in the one day type load follow-up intermittent operation mode. Is determined, the predicted energy reduction amount P′c1 during normal heat generation efficiency in the load following continuous operation mode, the predicted energy reduction amount P′c2 during normal heat generation efficiency in the suppressed continuous operation mode, and normal heat generation in the forced continuous operation mode When the predicted energy reduction amount at the maximum normal heat generation efficiency among the predicted energy reduction amounts P′c3 at the efficiency is greater than or equal to the negative value “−Z” of the standby energy consumption Z, the predicted energy reduction at the normal heat generation efficiency The continuous operation mode with the maximum amount is set as the operation mode of the fuel cell 1 (steps # 25 and 26), and the predicted energy reduction amount at the maximum normal heat generation efficiency is the negative value “−Z” of the standby energy consumption Z. Remote smaller defines a standby mode to the operation mode of the fuel cell 1 (step # 31)

  In step # 24, it is determined that the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is smaller than the predicted energy reduction amount Pi1 at the time of low heat generation efficiency in the one day correspondence type load tracking intermittent operation mode. In step # 27, the thermal load coverage rate U / L is obtained in the same manner as in the first embodiment. In step # 28, the obtained thermal load coverage rate U / L is compared with the lower set value K. When the thermal load coverage rate U / L is larger than the lower set value K, it is determined that the standby condition is satisfied. When the thermal load coverage rate U / L is lower than the lower set value K, the standby condition must be satisfied. to decide.

  When it is determined in step # 28 that the standby condition is not satisfied, the load following intermittent operation mode corresponding to one day, the suppression intermittent operation mode corresponding to one day, the forced intermittent operation mode corresponding to one day, the second day Corresponding type load following intermittent operation mode, 2 day type restrained intermittent operation mode, 2 day type forced forced intermittent mode, 3 day type load following intermittent mode, 3 day type intermittent mode Predicted energy reduction amount Pi1, Pi2, Pi3, Pi4, Pi5, Pi6, Pi7, Pi8, Pi9 at the time of low heat generation efficiency of nine types of three-day type forced intermittent operation forms. When the predicted energy reduction amount at the time is equal to or greater than the negative value “−Z” of the standby consumption energy Z, the intermittent operation mode with the maximum predicted energy reduction amount at the time of low heat generation efficiency is determined as the operation mode of the fuel cell 1 ( Step # 29, 30 When the predicted energy reduction amount at the time of the maximum low heat generation efficiency is smaller than the negative value “−Z” of the standby energy consumption Z, the standby mode is determined as the operation mode of the fuel cell 1 (steps # 29 and 31). .

  If it is determined in step # 28 that the standby condition is satisfied, it is determined in step # 32 whether or not the fuel cell 1 is in operation. If it is in operation, in step # 33, the thermal load coverage rate U is determined. When it is determined whether / L is larger than the upper set value M (for example, 0.9) that is larger than the lower set value K and not larger, in step # 34, the first embodiment is compared with the first embodiment. Similarly, it is determined whether or not the operation continuation condition for continuing the operation of the fuel cell 1 is satisfied. If it is determined that the operation continuation condition is satisfied, the operation of the fuel cell 1 is continued in the load following operation in step # 35. The load follow-up operation continuation mode is set, and in step # 36, the operation continuation time setting process for setting the operation continuation time is executed in the same manner as in the first embodiment.

When it is determined in step # 32 that the fuel cell 1 is stopped, in step # 33, when it is determined that the thermal load coverage ratio U / L is larger than the upper set value M, in step # 34 If it is determined that the operation continuation condition is not satisfied, the standby mode is set at step # 31.
Then, similarly to the first embodiment, the operation control unit 5 operates the fuel cell 1 in the operation mode determined in the operation mode selection process.

Also in the second embodiment, as in the first embodiment, the operation control unit 5 uses the latent heat recovery type auxiliary heating as the heat generation efficiency of the auxiliary heater 28 in the operation mode selection process. The predicted energy consumption during the continuous operation and the predicted energy consumption during the intermittent operation are obtained by using the heat generation efficiency for selecting the operation mode set to a value lower than the heat generation efficiency of the vessel 28. .
Further, when the operation control unit 5 determines that the operation mode of the fuel cell 1 is the continuous operation mode in the operation mode selection process, the continuous heating mode is used to generate the continuous heat using the latent heat recovery type auxiliary heater 28. A predicted energy consumption amount during operation is obtained, and a power generation output of the fuel cell 1 is determined based on the predicted energy consumption amount.
Furthermore, when the operation control unit 5 determines the operation mode of the fuel cell 1 to be the intermittent operation mode in the operation mode selection process, the heat generation efficiency for selecting the operation mode is used to predict the intermittent operation. An energy consumption amount is obtained, and an operation time zone of the fuel cell 1 is determined based on the predicted energy consumption amount.

[Third Embodiment]
The third embodiment of the present invention will be described below.
In the third embodiment, another embodiment of the operation mode selection condition will be described.
That is, also in the third embodiment, as in each of the first and second embodiments, the operation mode selection condition includes the predicted energy consumption during the continuous operation and the predicted energy consumption during the intermittent operation. The predicted driving merit for each quantity is set as an index for selecting the driving mode, and the conditions for determining the driving mode of the fuel cell 1 based on the driving mode selecting index are set. In this third embodiment, the predicted driving is set. As a merit, it differs from each of the first and second embodiments in that a predicted carbon dioxide reduction amount that is predicted to be obtained by operating the fuel cell 1 is obtained.

  The predicted amount of carbon dioxide reduction for each operation mode is calculated from the predicted amount of carbon dioxide emission when the fuel cell 1 is not operated, as shown in the following formula 15, when the fuel cell 1 is operated in each operation mode. Calculate by reducing the predicted carbon dioxide emissions.

  Predicted carbon dioxide reduction amount = predicted carbon dioxide emission amount D1 when the fuel cell 1 is not operated D1-predicted carbon dioxide emission amount D2 when the fuel cell 1 is operated (Equation 15)

  The predicted carbon dioxide emission amount D1 (kg) when the fuel cell 1 is not operated is a case where all of the predicted load power in the first operation cycle is supplemented with the received power from the commercial power supply 7, as shown in the following equation 16. Is calculated as the sum of the predicted carbon dioxide emission amount and the predicted carbon dioxide emission amount when all of the predicted load heat amount in the first operation cycle is supplemented with the heat generated by the auxiliary heater 28.

  D1 = predicted load power × carbon dioxide generation basic unit of thermal power plant + (predicted load calorie / ÷ R) × 3.6 × city gas carbon dioxide generation basic unit …………… (Formula 16)

  On the other hand, the predicted carbon dioxide emission amount D2 (kg) when the fuel cell 1 is operated is calculated by using the predicted load power and the predicted load heat amount of the first operation cycle as the predicted power generation output of the fuel cell 1 as shown in the following Expression 17. And the predicted carbon dioxide emission when supplementing with the predicted heat output, and the predicted carbon dioxide emission when all of the predicted insufficient power corresponding to the amount obtained by subtracting the predicted power output from the predicted load power is supplemented with the received power from the commercial power source 7. It is obtained by the sum of the exhaust amount and the predicted carbon dioxide emission amount when all of the predicted insufficient heat amount is supplemented with the heat generated by the auxiliary heater 28.

  E2 = operating cycle predicted energy consumption × 3.6 × city gas generation unit of carbon gas + predicted insufficient power amount × carbon dioxide generation unit of thermal power plant + (predicted insufficient heat amount / R) × 3.6 × city Basic unit of gas carbon dioxide generation ……………… (Formula 17)

  In the operation mode selection process, the operation mode of the fuel cell 1 is determined by obtaining the predicted carbon dioxide reduction amount instead of the predicted energy reduction amount for each of the plurality of types of continuous operation modes and each of the plurality of types of intermittent operation modes. In this case, the heat generation efficiency R of the auxiliary heater 28 is set as latent heat recovery, as in the first embodiment or the second embodiment. The heat generation efficiency R2 of the mold auxiliary heater 28 and the heat generation efficiency R1 for selecting the operation mode determined to be lower than the heat generation efficiency R2 of the latent heat recovery type auxiliary heater 28 are used.

[Another embodiment]
Next, another embodiment will be described.
(A) In each of the first and second embodiments, in the operation mode selection process, the predicted energy reduction amount is obtained in advance for all of the plurality of types of continuous operation modes and the plurality of types of intermittent operation modes. In the case of performing processing such as comparison between the predicted energy reduction amount of the continuous operation mode and the predicted energy reduction amount of the intermittent operation mode, the case of picking up necessary ones from the predicted energy reduction amount obtained in advance is illustrated. You may comprise so that the prediction energy reduction amount of a required driving | running form may be calculated | required whenever processing, such as a comparison with the prediction energy reduction amount of a form, and the prediction energy reduction amount of an intermittent driving | running mode, is performed.

For example, in the first embodiment, the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is obtained, and the predicted energy reduction amount Pc1 at the time of low heat generation efficiency is compared with the set reduction amount G. If the predicted energy reduction amount Pc1 at the time of low heat generation efficiency is equal to or greater than the set reduction amount G, the predicted energy reduction amounts P′c1 and P′c2 at the time of normal heat generation efficiency for each of the load following, suppression, and forced continuous operation modes. , P′c3 is determined, and the continuous operation mode having the maximum predicted energy reduction amount at the time of normal heat generation efficiency is determined as the operation mode of the fuel cell 1.
If the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is smaller than the set reduction amount G, the predicted energy reduction amount Pi1 at the time of low heat generation efficiency in the day-to-day load following intermittent operation mode is obtained. The predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is compared with the predicted energy reduction amount Pi1 at the time of low heat generation efficiency in the one day correspondence type load tracking intermittent operation mode.
When the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is smaller than the predicted energy reduction amount Pi1 at the time of low heat generation efficiency in the one day type load follow-up intermittent operation mode, further one day Corresponding suppression intermittent operation mode, forced intermittent operation mode, 2-day load follow intermittent operation mode, suppression intermittent operation mode, forced intermittent operation mode, 3-day load follow intermittent operation mode, suppression intermittent operation mode and For each of the forced intermittent operation modes, the predicted energy reduction amount Pi2, Pi3, Pi4, Pi5, Pi6, Pi7, Pi8, and Pi9 at the time of low heat generation efficiency is obtained, and the intermittent operation mode having the maximum predicted energy reduction amount at the time of low heat generation efficiency is obtained. The fuel cell 1 is configured as defined in the operation mode.

  In the second embodiment, the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load follow-up continuous operation mode and the predicted energy reduction amount Pi1 at the time of heat generation efficiency in the day-to-day load follow-up intermittent operation mode are obtained. If the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is equal to or greater than the predicted energy reduction amount Pi1 at the time of heat generation efficiency in the one day correspondence type load following intermittent operation mode, the load For each follow-up, suppression, and forced continuous operation mode, the predicted energy reduction amounts P′c1, P′c2, and P′c3 at the normal heat generation efficiency are obtained, and the continuous operation with the maximum predicted energy reduction amount at the normal heat generation efficiency is obtained. The mode is determined as the operation mode of the fuel cell 1, and the predicted energy reduction amount Pc1 at the time of low heat generation efficiency in the load following continuous operation mode is low heat generation efficiency in the load follow intermittent operation mode of one day type If it is smaller than the predicted energy reduction amount Pi1, it is further reduced to a 1-day type suppression intermittent operation mode, a forced intermittent operation mode, a 2-day type load follow-up intermittent operation mode, a controlled intermittent operation mode, a forced intermittent operation mode, 3 days. Low heat generation is obtained by calculating the predicted energy reduction amount Pi2, Pi3, Pi4, Pi5, Pi6, Pi7, Pi8, Pi9 at the time of low heat generation efficiency for each of the corresponding load following intermittent operation mode, suppression intermittent operation mode and forced intermittent operation mode. The intermittent operation mode in which the predicted energy reduction amount at the time of efficiency is the maximum is determined as the operation mode of the fuel cell 1.

(B) In each of the first and second embodiments described above, when the predicted energy reduction amount at the time of low heat generation efficiency in the continuous operation mode is obtained, and the predicted energy reduction amount at the time of low heat generation efficiency in the intermittent operation mode is obtained. In this case, using the heat generation efficiency R1 for selecting the operation mode, the predicted energy consumption E1 when the fuel cell 1 is not operated is obtained, and when the predicted energy reduction amount at the normal heat generation efficiency in the continuous operation mode is obtained, the latent heat The recovery type heat generation efficiency R2 is used to determine the predicted energy consumption E1 when the fuel cell 1 is not operated. However, when the predicted energy reduction amount at the time of low heat generation efficiency in the continuous operation mode is determined, the intermittent operation mode is low. In either case of obtaining the predicted energy reduction amount at the time of the heat generation efficiency or obtaining the predicted energy reduction amount at the time of the normal heat generation efficiency in the continuous operation mode, the heat generation efficiency R1 for selecting the operation mode By using the heat generation efficiency of one of the same value of heat generation efficiency R2 of latent heat recovery type, may be obtained predicted energy consumption E1 when not operating the fuel cell 1.

(C) The operation mode selection conditions are not limited to the conditions defined in the first to third embodiments.
For example, the predicted energy consumption during continuous operation and the predicted energy consumption during intermittent operation itself are used as the operation mode selection index, and the same procedure as in the first and second embodiments based on the operation mode selection index. Thus, the conditions for determining the operation mode of the fuel cell 1 may be set. In this case, each predicted energy consumption during continuous operation and intermittent operation is obtained by the above equation 10.
Further, the predicted energy consumption during the continuous operation and the predicted carbon dioxide emission for the predicted energy consumption during the intermittent operation are used as the operation mode selection index, and the first and second parameters are selected based on the operation mode selection index. You may set to the conditions which determine the driving | running form of the fuel cell 1 in the procedure similar to each embodiment. In this case, each predicted carbon dioxide emission amount at the time of continuous operation and intermittent operation is obtained by the above equation 17.
In addition, the first and second embodiments are based on the operation mode selection index using the utility cost for each of the predicted energy consumption during continuous operation and the predicted energy consumption during intermittent operation as an operation mode selection index. You may set to the conditions which determine the driving | running form of the fuel cell 1 in the procedure similar to.

In addition, when the predicted operation merit for each of the predicted energy consumption during continuous operation and the predicted energy consumption during intermittent operation is used as an index for selecting the operation mode, It is not limited to the predicted energy reduction amount exemplified in the embodiment or the predicted carbon dioxide reduction amount exemplified in the third embodiment, and may be, for example, a predicted utility cost reduction amount.
The predicted reduction in the utility cost can be obtained by subtracting the utility cost when the fuel cell 1 is operated from the utility cost when the fuel cell 1 is not operated.
When the fuel cell 1 is not operated, the utility cost is the cost of purchasing all of the predicted power load from the commercial power source 7 and the energy cost of supplying all of the predicted heat load with the auxiliary heater 28 (fuel cost). ).
On the other hand, the utility costs when the fuel cell 1 is operated are the energy cost (fuel cost) of the fuel cell 1 when the predicted load power and the predicted load heat amount are supplemented by the predicted power generation output and the predicted heat output of the fuel cell 1, and the prediction The cost for purchasing the predicted insufficient power corresponding to the amount obtained by subtracting the predicted power output from the load power from the commercial power supply 7 and the energy cost for supplementing the predicted insufficient power with the heat generated by the auxiliary heater 28 (fuel cost) As the sum of

(D) The specific set value of the heat generation efficiency for selecting the operation mode is not limited to the heat generation efficiency of the non-latent heat recovery type auxiliary heating means as exemplified in the first to third embodiments. Alternatively, it may be set to a value higher or lower than the heat generation efficiency of the non-latent heat recovery type auxiliary heating means.

(E) In each of the first to third embodiments described above, the continuous operation mode has been illustrated with respect to the case of including three types of load following, suppression, and forced, but any one of these three types is used. Or may be configured to include any two of them. Moreover, you may provide the rated continuous operation which adjusts the electric power generation output of the fuel cell 1 to a rated output (for example, the maximum output of a power generation output adjustment range).
As the intermittent operation mode, the case of including three types of load following, suppression, and forced is exemplified, but any one of these three types may be provided, or any two types may be configured. . In addition, the load following, suppression, and forced intermittent operation modes have been illustrated with the case of having a one-day correspondence type, a two-day correspondence type, and a three-day correspondence type. And a 2-day compatible type, or a 4-day compatible type may be added.

(F) Although the fuel cell 1 is applied in each of the above-described embodiments as a combined heat and power supply device, in addition to this, various devices such as a configuration in which a generator is driven by a gas engine may be applied. Can do.

The block diagram which shows the whole structure of the cogeneration system which concerns on embodiment The block diagram which shows the control structure of the cogeneration system which concerns on embodiment The figure explaining the process which calculates | requires prediction energy reduction amount The figure which shows the battery power generation efficiency and battery thermal efficiency of the fuel cell Figure showing the amount of heat generated when output is increased and the difference in energy amount for power generation when output is suppressed The figure which shows the flowchart of the control action which concerns on 1st Embodiment. The figure which shows the flowchart of the control action which concerns on 2nd Embodiment.

Explanation of symbols

1 Cogeneration device 5 Operation control means 28 Auxiliary heating means

Claims (5)

A cogeneration device that generates both electric power and heat, a combustion type latent heat recovery type auxiliary heating means, and an operation control means for controlling the operation,
When the operation control means continuously operates the cogeneration device based on the time-series predicted load power, the time-series predicted load heat amount, and the heat generation efficiency of the auxiliary heating means at the periodic operation mode selection timing. The predicted energy consumption during continuous operation when it is assumed and the predicted energy consumption during intermittent operation when it is assumed that the combined heat and power supply device is intermittently operated are obtained. Based on the predicted energy consumption at the time of intermittent operation and the operation mode selection condition, any of the operation mode of the combined heat and power supply device is a continuous operation mode, the intermittent operation mode or the standby mode in which the combined heat and power supply device is stopped and waits for the operation. A cogeneration system configured to execute the operation type selection process defined in
In the operation mode selection process, the operation control means uses, as the heat generation efficiency of the auxiliary heating means, the heat generation efficiency for operation mode selection set to a value lower than the heat generation efficiency of the latent heat recovery type auxiliary heating means. A cogeneration system configured to obtain a predicted energy consumption during the continuous operation and a predicted energy consumption during the intermittent operation.   The cogeneration system according to claim 1, wherein the heat generation efficiency for selecting the operation mode is determined as the heat generation efficiency of the non-latent heat recovery type auxiliary heating means.   When the operation control means sets the operation mode of the combined heat and power device to the intermittent operation mode in the operation mode selection process, the operation and power supply device is operated in the intermittent operation mode with different operation time zones. For each of the cases, the predicted energy consumption during the intermittent operation is obtained using the heat generation efficiency for selecting the operation mode, and the operation time zone in which the predicted energy consumption is low is determined as the operation time zone of the combined heat and power supply device. The cogeneration system according to claim 1 or 2, configured as described above.   When the operation control means sets the operation mode of the cogeneration device to the continuous operation mode in the operation mode selection process, and operates the cogeneration device in the continuous operation mode with different power generation outputs. For each of the above, the predicted energy consumption during the continuous operation is obtained using the heat generation efficiency of the auxiliary heating means of the latent heat recovery type, and the power generation output with the small predicted energy consumption is determined as the power generation output of the cogeneration device. The cogeneration system according to any one of claims 1 to 3, which is configured as described above.   The operation mode selection condition is any one of a predicted carbon dioxide emission amount, a predicted utility cost, and a predicted operation merit for each of the predicted energy consumption during the continuous operation and the predicted energy consumption during the intermittent operation. The cogeneration system according to any one of claims 1 to 4, wherein the operation mode selection index is set to a condition that determines the operation mode of the combined heat and power supply device based on the operation mode selection index.

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