JP2006060932A - Cogeneration system, power generation control method therefor, and power generation control device therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively feed power and heat by performing power generation that can deal with an abrupt heat load and/or a power load by compensating a power generation amount as needed. <P>SOLUTION: This power generation control device 40 of a cogeneration system calculates a heat amount per unit hour of a heat amount necessary until a hot-water demand peak time comes, on the basis of a time until the hot-water demand peak time comes, and an excessive or insufficient amount of hot water at the peak time at each prescribed hour (a per-unit-time heat amount calculation part 51); calculates a power generation amount necessary for generating the amount of heat as a power generation correction amount (a power generation correction amount calculation part 52) and detects power consumption at a load device; calculates output power at each prescribed hour on the basis of these calculated power generation correction amounts and the detected power consumption (a power generation amount indication value calculation part 53); and controls a power generator so as to generate the output power. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cogeneration system, a power generation control method for the system, and a power generation control device for the system.

  The cogeneration system includes a power generator that supplies power to the load device, and a hot water tank that stores hot water heated by the heat energy generated during power generation and supplies the stored hot water. It has been known. According to this system, high energy use efficiency is achieved by supplying both electric power and heat by generating power using city gas as fuel and using the exhaust heat (heat energy) generated at that time to cool and heat and hot water. is doing. Known power generators for cogeneration systems include diesel engines, gas engines, gas turbines, micro gas turbines and other prime movers and generators driven by these prime movers, and fuel cells. ing.

As an example of the power generation control method of this cogeneration system, there is an operation method of a cogeneration facility disclosed in Patent Document 1. As shown in Patent Document 1, a cogeneration facility that supplies power in a grid-connected manner with commercial power and uses waste heat as hot water in an apartment house including a plurality of dwellings, such as a condominium, is introduced. . The cogeneration facility to be introduced is provided with a hot water storage tank capable of storing hot water, and is operated according to a schedule set for each predetermined operation cycle. The schedule predicts the power load and heat load of the operation cycle, and the heat quantity necessary at the peak of heat load can be supplied by starting operation of the cogeneration facility and storing hot water Set to. The operation of the cogeneration facility sets the ON time to start the operation ahead of the peak of the heat load, assuming that the power load predicted by the main operation that always receives more than a predetermined amount of power is supplied. The time point at which generation of the total amount of heat predicted as a load is completed is set as an OFF time when the operation of the cogeneration facility is to be stopped. Since the cogeneration facility is operated from the ON time to the OFF time across the peak time of the heat load, it is possible to efficiently supply power and heat. Since the power load and the heat load are predicted for each operation cycle, a schedule is set, and the cogeneration facility is operated according to the set schedule, so that appropriate operation can be performed.
JP 2003-087970 A (page 1-7, FIG. 1-7)

  In the operation method of the cogeneration facility described in Patent Document 1 described above, since the cogeneration facility is operated from the ON time to the OFF time that sandwich the peak time of the heat load, it is possible to efficiently supply power and heat. In order to predict the power load and heat load at each operation cycle and set the schedule and operate the cogeneration facility according to the set schedule, sudden increase in heat load due to sudden hot water consumption etc. or sudden power If there is a sudden increase in power load due to consumption, etc., operating according to the schedule set for each operation cycle, the amount of hot water stored at the peak is less than the desired amount, or the amount of hot water stored is desired before reaching the peak On the contrary, there is a possibility that the supply efficiency of power and heat is deteriorated.

  The present invention has been made in order to solve the above-described problem. By correcting the amount of power generation as needed and performing power generation corresponding to a sudden heat load and / or power load, the power and heat can be efficiently generated. It aims at providing the cogeneration system which can be supplied.

  In order to solve the above problems, the structural feature of the invention according to claim 1 is that a power generation device that supplies power to a load device and hot water heated by thermal energy generated during power generation are stored. In a power generation control method for a cogeneration system having a hot water tank that supplies hot water that has been stored, hot water is supplied at predetermined time intervals based on the time until the hot water demand peak time and the excess or shortage of hot water at the peak time. Calculate the amount of heat per unit time of the amount of heat required until the peak demand time, calculate the amount of power generation required to generate that amount of heat as a power generation correction amount, detect the power consumption in the load device, and calculate the power generation correction amount The output power is calculated every predetermined time based on the detected power consumption, and the power generator is controlled so as to be the output power.

  Further, the structural feature of the invention according to claim 2 is that, in claim 1, the time to the hot water demand peak time is based on the time when the power generation correction amount is calculated and the power consumption is detected and the hot water demand pattern. It is to calculate.

  Further, the structural feature of the invention according to claim 3 is that in claim 1, the excess or deficiency amount of hot water at the hot water demand peak time is calculated based on the predicted hot water supply amount, the predicted hot water consumption amount, and the remaining hot water amount in the hot water tank. It is to be.

  The structural feature of the invention according to claim 4 is that, in claim 3, the predicted hot water supply amount is calculated based on the power demand pattern and the time until the hot water demand peak time.

  The structural feature of the invention according to claim 5 is that, in claim 3, the hot water consumption predicted amount is calculated based on the hot water demand pattern and the time until the hot water demand peak time.

  The structural feature of the invention according to claim 6 is that the power generator for supplying electric power to the load device and hot water heated by the thermal energy generated during power generation are stored and the stored hot water is supplied. In a power generation control device for controlling power generation of a cogeneration system having a hot water storage tank, a hot water demand peak time based on the time until the hot water demand peak time and the excess and deficiency of hot water at the same peak time for each predetermined time The calorific value calculation means for calculating the calorific value per unit time of the calorie required up to and the power generation amount necessary for generating the calorie per unit time calculated by the calorie calculation means per unit time as the power generation correction amount Power generation correction amount calculation means for calculating, power consumption detection means for detecting power consumption in the load device every predetermined time, and power generation correction amount calculation means Thus it is that a power generation amount instruction value calculation means for outputting power generation device calculates a power generation amount instruction value based on the power consumption detected by the calculated power correction amount and the power consumption detecting means.

  Further, the structural feature of the invention according to claim 7 is that in claim 6, the calorific value calculation means per unit time calculates the power generation correction amount and detects the power consumption and the hot water demand pattern based on the hot water demand pattern. Time calculation means for calculating the time until the peak demand time, and hot water for calculating the excess or deficiency of the hot water at the peak demand time of the hot water based on the predicted hot water supply amount, the predicted hot water consumption amount, and the remaining hot water amount in the hot water tank And the excess / deficiency calculation means.

  Further, the structural feature of the invention according to claim 8 is that in claim 7, the hot water excess / deficiency calculating means calculates the predicted hot water supply based on the power demand pattern and the time to the hot water demand peak time. It is comprised from a warm water supply prediction amount calculation means and a warm water consumption prediction amount calculation means for calculating a warm water consumption prediction amount based on the warm water demand pattern and the time until the hot water demand peak time.

  The structural feature of the invention according to claim 9 is that the power generator for supplying power to the load device and hot water heated by thermal energy generated during power generation are stored and the stored hot water is supplied. In a cogeneration system equipped with a hot water storage tank and a power generation control device that controls power generation of the power generation device, the power generation control device is configured to provide excess or shortage of hot water at the same peak time as the time until the hot water demand peak time every predetermined time. To calculate the amount of heat per unit time of the amount of heat required until the hot water demand peak time based on the amount, and to generate the amount of heat per unit time calculated by the amount of heat calculated per unit time A power generation correction amount calculating means for calculating a necessary power generation amount as a power generation correction amount, and a power consumption detection for detecting power consumption in the load device every predetermined time. And a power generation amount instruction value calculation unit that calculates a power generation amount instruction value based on the power generation correction amount calculated by the power generation correction amount calculation unit and the power consumption detected by the power consumption detection unit and outputs the power generation amount instruction value to the power generator. It is to have.

  In the invention according to claim 1 configured as described above, the amount of heat required until the hot water demand peak time based on the time until the hot water demand peak time and the excess / deficiency amount of the hot water at the peak time every predetermined time. Calculate the amount of heat per unit time and calculate the amount of power generation required to generate the amount of heat as a power generation correction amount, detect the power consumption in the load device, and based on the calculated power generation correction amount and the detected power consumption Since the output power is calculated every predetermined time and the power generator is controlled so that the output power is obtained, the power generation amount is corrected at any time to generate power corresponding to the sudden heat load and / or power load. Thus, electric power and heat can be supplied efficiently.

  In the invention according to claim 2 configured as described above, in the invention according to claim 1, the time until the hot water demand peak time is calculated, and the time and hot water demand pattern for calculating the power generation correction amount and detecting the power consumption. Therefore, the time until the hot water demand peak time can be reliably calculated.

  In the invention according to claim 3 configured as described above, in the invention according to claim 1, the excess / deficiency amount of hot water at the hot water demand peak time is calculated based on the predicted hot water supply amount, the predicted hot water consumption amount, and the remaining hot water amount in the hot water tank. Therefore, it is possible to reliably calculate the excess / deficiency amount of hot water at the hot water demand peak time.

  In the invention according to claim 4 configured as described above, in the invention according to claim 3, the hot water supply predicted amount is calculated based on the power demand pattern and the time until the hot water demand peak time. The amount of hot water supplied by power generation by the peak time can be reliably predicted.

  In the invention according to claim 5 configured as described above, in the invention according to claim 3, the hot water consumption predicted amount is calculated based on the hot water demand pattern and the time until the hot water demand peak time. The amount of hot water consumed by the peak time can be reliably predicted.

  In the invention according to claim 6 configured as described above, the calorific value calculation unit per unit time is based on the time until the hot water demand peak time and the excess / deficiency amount of hot water at the peak time for each predetermined time. Calculate the heat per unit time of the heat required by the peak demand time, and the power generation correction amount calculation means corrects the power generation necessary to generate the heat per unit time calculated by the heat amount calculation means per unit time. The power consumption detection means detects the power consumption in the load device every predetermined time, and the power generation amount instruction value calculation means detects the power generation correction amount calculated by the power generation correction amount calculation means and the power consumption detection means. A power generation amount instruction value is calculated based on the power consumption and output to the power generation apparatus. As a result, since the output power is calculated every predetermined time based on the calculated power generation correction amount and the detected power consumption, and the power generation device is controlled to be the output power, the power generation amount is corrected as needed. Thus, by performing power generation corresponding to the sudden heat load and / or power load, it is possible to efficiently supply power and heat.

  In the invention according to claim 7 configured as described above, in the invention according to claim 6, the time when the time calculation means to the peak time calculates the power generation correction amount and detects the power consumption and the hot water demand pattern The hot water excess / deficiency calculation means calculates the amount of excess hot water at the hot water demand peak time based on the predicted hot water supply amount, the predicted hot water consumption amount, and the remaining hot water amount in the hot water tank. Since the shortage amount is calculated, the heat amount per unit time of the heat amount required until the hot water demand peak time can be reliably calculated.

  In the invention according to claim 8 configured as described above, in the invention according to claim 7, the hot water supply predicted amount calculating means is configured to calculate the predicted hot water supply amount based on the power demand pattern and the time until the hot water demand peak time. And the hot water consumption forecast amount calculation means calculates the hot water consumption forecast amount based on the hot water demand pattern and the time to the hot water demand peak time, so the excess and deficiency amount of hot water at the hot water demand peak time is calculated reliably. can do.

  In the invention according to claim 9 configured as described above, the calorific value calculation means per unit time is based on the time until the hot water demand peak time and the excess / deficiency amount of hot water at the peak time for each predetermined time. Calculate the heat per unit time of the heat required by the peak demand time, and the power generation correction amount calculation means corrects the power generation necessary to generate the heat per unit time calculated by the heat amount calculation means per unit time. The power consumption detection means detects the power consumption in the load device every predetermined time, and the power generation amount instruction value calculation means detects the power generation correction amount calculated by the power generation correction amount calculation means and the power consumption detection means. By calculating the power generation amount instruction value based on the calculated power consumption and outputting it to the power generation device, the power generation control device detects the calculated power generation correction amount and the detected consumption Based on the force calculates the output power at every predetermined time to control the power generator such that its output power. As a result, it is possible to efficiently supply power and heat by correcting the power generation amount as needed and performing power generation corresponding to sudden heat load and / or power load.

  Hereinafter, an embodiment of a cogeneration system according to the present invention will be described. FIG. 1 is a schematic diagram showing an overview of this cogeneration system. This cogeneration system includes a power generation device 10 that supplies power to the load device 21, a hot water tank 30 that stores hot water heated by heat energy generated during power generation and supplies the stored hot water, And a power generation control device 40 that controls power generation of the power generation device 10.

  The power generation device 10 is a fuel cell power generation device, and includes a power generator 11 that generates DC power, and a converter (for example, an inverter) 12 that converts the DC power supplied from the power generator 11 into AC power and outputs the AC power. ing. In addition to the fuel cell power generation device, the power generation device 10 includes a prime mover such as a diesel engine, a gas engine, a gas turbine, and a micro gas turbine and a generator driven by the prime mover.

  The power generator 11 includes a reformer 11a, a carbon monoxide reduction device (hereinafter referred to as a CO reduction device) 11b, and a fuel cell 11c. The reformer 11a steam-reforms the fuel (for example, city gas) supplied from the fuel supply device 13 with the water (reformed water) supplied from the water supply device 14 to generate a hydrogen-rich reformed gas. To the CO reduction device 11b. The CO reducing device 11b is a so-called carbon monoxide shift reaction in which carbon monoxide and water vapor are converted into hydrogen gas and carbon dioxide by a catalyst, or / and carbon monoxide and air for carbon monoxide oxidation further supplied from the outside. The carbon monoxide contained in the reformed gas is reduced and led out to the fuel cell 11c, for example, by a reaction that generates carbon dioxide by reacting the catalyst with a catalyst. The fuel cell 11c generates power using hydrogen in the reformed gas supplied to the fuel electrode 11c1 and air (cathode air) that is an oxidant gas supplied to the air electrode 11c2.

  The converter 12 is connected to each of a plurality of load devices 21 installed at a power usage place 20 that is a user via a power transmission line 15, and the AC power output from the converter 12 is as necessary. It is supplied to each load device 21. The load device 21 is an electric appliance such as an electric lamp, iron, television, washing machine, electric kotatsu, electric carpet, air conditioner, and refrigerator. In addition, the power source 15 of the electric power company is also connected to the power transmission line 15 connecting the converter 12 and the power use place 20 (system connection), and the total power consumption of the load device 21 is determined by the power generation amount of the power generation device 10. Is exceeded, the insufficient power is received from the system power supply 16 and compensated. The wattmeter 22 detects the total power consumption of all the load devices 21 used in the power usage place 20 and transmits it to the power generation control device 40. The power generation control device 40 stores the received power consumption and creates / updates a power demand pattern to be described later.

  The fuel cell 11c may become high temperature due to reaction heat of hydrogen and oxygen, resistance heat generation inside the battery, etc., and a cooling water flow is used to cool the fuel cell 11c that has become high temperature to a predetermined temperature (predetermined temperature range). A path 11c3 is provided. The predetermined temperature (predetermined temperature range) is set to be the activation temperature range of the fuel cell catalyst.

  The introduction end of the cooling water passage 11c3 is connected to the other end of the introduction pipe 31 whose one end is connected to the lower end portion of the hot water tank 30, and the leading end of the cooling water passage 11c3 is one end of the upper end portion of the hot water storage tank 30. Are connected to a lead-out pipe 32 connected to. The introduction pipe 31 is provided with a pump 33 which is a cooling water delivery means. The pump 33 sucks low-temperature water or hot water from the lower part of the hot water tank 30 and pumps it toward the cooling water flow path 11c3 of the fuel cell 11c. To do. The introduction pipe 31 and the lead-out pipe 32 are provided with first and second temperature sensors 36 and 37, respectively, and the first and second temperature sensors 36 and 37 are the coolant inlet temperature T1 introduced into the fuel cell 11c. The coolant outlet temperature T2 derived from the fuel cell 11c is detected and transmitted to the power generation control device 40. The pump 33 is connected to the power generation control device 40. The power generation control device 40 detects the cooling water inlet temperature and the cooling water outlet temperature detected from the first and second temperature sensors 36 and 37 and the remaining hot water amount sensor in the hot water tank 30, respectively. Based on the remaining hot water amount, the driving / stopping and discharging amount of the pump 33 is determined, and the pump 33 is controlled so as to obtain the determination result. When the pump 33 is driven, the low-temperature water or hot water sucked from the lower part of the hot water tank 30 is raised to a predetermined temperature (for example, about 70 ° C.) by the fuel cell 11c and returned to the upper part of the hot water tank 30. .

  The hot water tank 30 is provided with one columnar container, in which hot water is stored in a layered manner, that is, hot water in the upper part is the hottest and becomes lower as it goes to the lower part, and the hot water in the lower part is stored at the lowest temperature. It has become so. Hot water stored in the hot water tank 30 is led out from the upper part of the columnar container of the hot water tank 74, and water such as tap water (low temperature) is supplied from the lower part of the columnar container of the hot water tank 30 to replenish the derived amount. Water). Such a hot water tank 30 is installed near the power generation apparatus 10.

  In addition, a temperature sensor group 34 which is a remaining hot water amount detection sensor is provided inside the hot water tank 30. The temperature sensor group 34 includes a plurality (11 in the present embodiment) of temperature sensors 34-1, 34-2, 34-3,..., 34-11, and the vertical direction (vertical direction). Are arranged at equal intervals (tenths of the height in the vertical direction in the hot water tank 30). The temperature sensor 34-1 is disposed on the inner upper surface of the hot water tank 30. Each of the temperature sensors 34-1, 34-2, 34-3,..., 34-11 detects the temperature of the liquid (hot water or water) in the hot water storage tank 30 at that position. The amount of remaining hot water in the hot water storage tank 30 is detected based on the detection result of the hot water temperature at each position by the temperature sensor group. The remaining hot water amount represents the remaining amount of hot water remaining in the hot water storage tank 30 that is equal to or higher than a predetermined temperature (for example, 60 ° C.). Therefore, for example, when each temperature sensor 34-1 to 34-3 detects 60 ° C. or more and each temperature sensor 34-4 to 34-11 detects less than 60 ° C., the remaining hot water amount detection sensor 34 Detects the amount of water (the amount of hot water) from the inner wall surface of the hot water tank 30 to the temperature sensor 34-3 as the amount of remaining hot water. The amount of remaining hot water at this time is 2/10 of the capacity of the hot water storage tank 30. Moreover, when each temperature sensor 34-1 to 34-10 detects 60 degreeC or more and each temperature sensor 34-11 has detected less than 60 degreeC, the remaining hot water amount detection sensor 34 is the capacity | capacitance of the hot water tank 30. Of 9/10 is detected as the amount of remaining hot water.

  The amount of remaining hot water between the temperature sensor detecting 60 ° C. or more and the temperature sensor detecting less than 60 ° C. is based on the temperature gradient calculated by a plurality of upper and lower temperature sensors including these two temperature sensors and the distance between the sensors. Therefore, the remaining hot water amount in the hot water storage tank 30 can be calculated more accurately by adding up the calculated remaining hot water amounts between the sensors.

  Further, the outlet pipe 31 is provided with a radiator 35 which is a cooling water cooling means for cooling the overheated cooling water. The radiator 35 includes a blower or the like as an additional device for air-cooling itself.

  The hot water tank 30 is connected to a hot water use place 17 such as a kitchen or a bathroom via a hot water supply pipe 38. When hot water is used in the hot water use place 17, the hot water in the hot water tank 30 is used as the hot water use place. 17 is supplied. The hot water supply pipe 38 is provided with a flow meter 39 which is a flow rate detecting means for detecting the flow rate of the hot water supply pipe 38, and the flow meter 39 performs power generation control on the detected hot water flow rate of the hot water supply pipe 38, that is, hot water consumption. The data is transmitted to the device 40. The power generation control device 40 stores the received hot water consumption and creates / updates a hot water demand pattern to be described later.

  When the hot water in the hot water storage tank 30 is used up and the hot water supply from the hot water heater 18 is received, the power generation control device 40 receives the fuel consumption of the hot water heater 18. That is, fuel from the fuel supply device 13 is supplied to the water heater 18 via a fuel supply pipe 19, and the fuel supply pipe 19 is provided with a flow meter 19 a that is a flow rate detecting means for detecting the flow rate of the fuel. It has been. The flow meter 19 a transmits the detected fuel flow rate of the fuel supply pipe 19, that is, the fuel consumption amount, to the power generation control device 40. Then, the power generation control device 40 calculates the amount of hot water generated by the water heater 18 based on the received fuel consumption (which can be calculated from the fuel consumption), that is, the hot water consumption at the hot water use place 17, The hot water consumption pattern is stored and the hot water demand pattern described later is created and updated.

  As shown in FIG. 3, the power generation control device 40 displays the hot water demand pattern stored in the storage unit 41 a and the current time (current time) indicated by the timer 42 at predetermined time intervals (for example, every minute). A time calculation unit 43 up to the hot water demand peak time for calculating the time Ta up to the hot water demand peak time is provided. The time calculation unit 43 until the hot water demand peak time calculates the power generation correction amount and calculates the time Ta until the hot water demand peak time based on the time when the power consumption is detected, that is, the current time and the hot water demand pattern. .

  As shown in FIG. 4, the hot water demand pattern indicates a hot water demand pattern at the hot water use place 17 and shows a time-dependent hot water fluctuation pattern. The hot water demand pattern is stored in advance in the storage unit 41a. In this embodiment, as shown in FIG. 4, hot water is consumed for breakfast preparation from 7:00 to 7:30, and hot water is consumed for cleaning up the breakfast from 8:10 to 8:30. Has been. Hot water is consumed from 12:00 to 12:20 for lunch preparation, and hot water is consumed from 12:00 to 13:00 for cleaning up after lunch. Hot water is consumed for dinner from 17:50 to 18:20, and hot water is consumed for cleaning up after 19:00 to 19:20. And hot water is consumed for bathing (hot water, shower) from 20:00 to 20:30. Thus, there are a plurality of time zones in which hot water is used continuously, that is, hot water demand peaks. Among them, the one with the largest amount of hot water is selected as the hot water demand maximum peak, and the start time of the time zone is set as the hot water demand peak time. In the present embodiment, the hot water demand maximum peak is a peak from 20:00 to 20:30, and the hot water demand peak time is 20:00.

  This hot water demand pattern is created in advance based on data obtained by actually measuring the amount of hot water consumed at the hot water use place 17. This data may be, for example, for one month, for one year, or for each season. Moreover, you may make it produce for every family structure. In this case, it is preferable to consider the number and age of men and women. The data measured and collected in this way is calculated by taking an average every 10 minutes, every 5 minutes, or every minute, and a hot water demand pattern is created based on the calculation result. In addition, if the hot water demand pattern created in advance as described above is stored in advance in the power generation control device 40, the hot water demand pattern can be used from the beginning of use of the power generation device 10. Power generation can be accurately controlled.

  Furthermore, it is preferable that the hot water demand pattern is updated every day using the hot water consumption detected and stored every predetermined time (for example, 1 minute) during use of the power generation apparatus 10. Specifically, the latest one month of data may be used to average them. According to this, the latest situation of hot water use can be reflected in the hot water demand pattern by using the latest data. The hot water consumption is the total consumption of hot water in the hot water tank 30 and hot water from the water heater 18.

  Furthermore, the hot water demand pattern may not be stored in advance in the power generation control device 40. In this case, the detected hot water consumption is stored from the beginning of use of the power generation device 10, and the hot water demand is based on the data. Create a pattern.

  The timer (timer counter) 42 counts time (indicates time), has a clock function, and transmits the time to the time calculation unit 43 up to the hot water demand peak time every predetermined time. ing. The time calculation unit 43 until the hot water demand peak time is the hot water that is the time from the current time input from the timer 42 to the hot water demand peak time derived from the hot water demand pattern (“20:00” in the present embodiment). The time Ta until the peak demand time is calculated. For example, when the current time is 20:30, the time Ta until the hot water demand peak time is 23 hours 30 minutes. The unit of time Ta until the hot water demand peak time is second [s].

  As shown in FIG. 3, the power generation control device 40 inputs a hot water demand pattern (see FIG. 4) stored in the storage unit 41 a and a time Ta until the hot water demand peak time for each predetermined time. A hot water consumption predicted amount calculation unit 44 that calculates a predicted amount of hot water consumed up to the hot water demand peak time is provided. That is, the predicted amount of hot water consumption calculation unit 44 consumes by the hot water demand peak time based on the hot water demand pattern and the time Ta until the hot water demand peak time derived from the time calculation unit 43 until the hot water demand peak time. Calculate the predicted consumption of warm water. Specifically, the predicted consumption of hot water consumed by the hot water demand peak time is calculated by adding the hot water consumption for the time Ta from the current time to the hot water demand peak time in the hot water demand pattern.

  The power generation control device 40 inputs the power demand pattern (see FIG. 5) stored in the storage unit 41b and the time Ta up to the hot water demand peak time and supplies the hot water demand peak time every predetermined time. A hot water supply predicted amount calculation unit 45 that calculates a predicted supply amount of hot water to be used is provided. That is, the predicted hot water supply amount calculation unit 45 is supplied by the hot water demand peak time based on the power demand pattern and the time Ta until the hot water demand peak time derived from the time calculation unit 43 until the hot water demand peak time. Calculate the expected amount of hot water supply. Specifically, a hot water fluctuation pattern by time indicating the amount of hot water generated by power generation based on the power demand pattern is derived, and hot water for the time Ta from the current time to the hot water demand peak time in the hot water fluctuation pattern by time By adding the supply amount, a predicted supply amount of hot water supplied up to the hot water demand peak time is calculated. If power is being received from the system power supply 16, it is necessary to subtract that amount.

  As shown in FIG. 5, the power demand pattern indicates a power demand pattern at the power usage place 20 and shows a time-dependent power fluctuation pattern. The power demand pattern is stored in advance in the storage unit 41b. In the present embodiment, power is consumed as shown in FIG. This power demand pattern is created in advance based on data obtained by actually measuring the power consumed at the power usage place 20. This data may be, for example, for one month, for one year, or for each season. Moreover, you may make it produce in consideration of the electrical appliance kind with which it is equipped, a life pattern, a family structure, etc. Data thus measured and collected is calculated by taking an average every 10 minutes, every 5 minutes, or every minute, and a power demand pattern is created based on the calculation result. In addition, if the power demand pattern created in advance as described above is stored in the power generation control device 40 in advance, the power demand pattern can be used from the beginning of use of the power generation device 10. Power generation can be accurately controlled.

  Furthermore, it is preferable that the power demand pattern is updated daily using the power consumption detected and stored every predetermined time (for example, 1 minute) while the power generation apparatus 10 is used. Specifically, the latest one month of data may be used to average them. According to this, the latest situation of power use can be reflected in the power demand pattern by using the latest data. Furthermore, the power demand pattern may not be stored in advance in the power generation control device 40. In this case, the detected power consumption is stored from the beginning of use of the power generation device 10, and the power demand is based on the data. Create a pattern.

The power generation control device 40 performs the hot water consumption prediction amount from the hot water consumption prediction amount calculation unit 44, the hot water supply prediction amount from the hot water supply prediction amount 45, and the hot water tank 30 from the hot water tank remaining hot water amount calculation unit 46 at predetermined time intervals. Are provided with an adding unit 47a for inputting the remaining amount of hot water at the present time and calculating the expected remaining amount of hot water at the hot water demand peak time. Specifically, the adding unit 47a calculates the expected remaining amount of hot water from the following equation (1).
(Equation 1)
Expected remaining amount of hot water = Current amount of hot water in the hot water tank + Expected amount of hot water supply-Expected amount of hot water consumption

  The hot water tank remaining hot water amount calculation unit 46 inputs the temperature of hot water at the place where each temperature sensor is arranged from the temperature sensor group 34, and based on these temperatures, the remaining hot water amount in the hot water tank 30, that is, a predetermined temperature (for example, 60 ° C.). ) The remaining amount of hot water is calculated. For example, when each temperature sensor 34-1 to 34-3 detects 60 ° C. or higher and each temperature sensor 34-4 to 34-11 detects less than 60 ° C., the remaining hot water amount detection sensor 34 stores hot water. The amount of water (the amount of hot water) from the inner wall surface of the tank 30 to the temperature sensor 34-3 is calculated as the amount of remaining hot water. The amount of remaining hot water at this time is 2/10 of the capacity of the hot water storage tank 30. In addition, the amount of remaining hot water between the temperature sensor which detected 60 degreeC or more and the temperature sensor which detected less than 60 degreeC is calculated based on the detection result detected by the upper and lower temperature sensors containing these both temperature sensors. Since it can be calculated based on the temperature gradient and the distance between the sensors, the remaining hot water amount in the hot water storage tank 30 can be calculated more accurately by adding the calculated remaining hot water amount between the sensors.

The power generation control device 40 inputs the capacity of the hot water tank 30 (for example, 150 liters in the present embodiment) stored in the storage unit 41c and the expected remaining amount of hot water from the adding unit 47a at each predetermined time. Then, an adding unit 47b for calculating an excess / deficiency amount W of hot water relative to the capacity of the hot water tank 30 at the hot water demand peak time is provided. Specifically, the adding unit 47b calculates the excess / deficiency amount W of the hot water from the following formula 2.
(Equation 2)
Hot water excess / deficiency W = capacity of hot water tank-predicted remaining amount of hot water Note that the capacity of the hot water tank 30 is previously input and stored in the storage unit 41c.

  Thus, in the addition part 47b, when the hot water demand amount required at the hot water demand peak time is larger than the capacity of the hot water tank 30, the hot water tank 30 is filled with hot water at a predetermined temperature or higher at the peak time. However, when the hot water demand required at the hot water demand peak time is smaller than the capacity of the hot water tank 30, the remaining hot water amount in the hot water tank 30 becomes the hot water demand required at the hot water demand peak time. Control may be performed as follows. Specifically, the hot water demand amount required at the hot water demand peak time and the remaining hot water expected amount from the adder 47a are respectively input, and the hot water excess / deficiency relative to the required hot water demand amount at the hot water demand peak time is input. What is necessary is just to calculate W.

The power generation control device 40 inputs the time Ta until the hot water demand peak time and the hot water excess / deficiency W at the hot water demand peak time from the adder 47b for each predetermined time, and from the present time to the hot water demand peak time. A heat amount calculation unit 51 per unit time for calculating the heat amount per unit time of the necessary heat amount Q is provided. That is, the heat quantity calculation unit 51 calculates the heat quantity (work rate, that is, power P) per unit time of the heat quantity Q required to raise the previously calculated excess / deficiency amount W of hot water by the predetermined temperature Δt. First, the calorie calculating unit 51 per unit time calculates the calorie Q necessary from the present time to the hot water demand peak time. Specifically, in addition to the excess / deficiency amount W of warm water, the temperature of warm water recovered from the fuel cell 11c (that is, the fuel cell cooling water outlet temperature T2 derived from the fuel cell 11c) and the fuel cell 11c are supplied. The temperature of hot water (that is, the fuel cell cooling water inlet temperature T1 introduced into the fuel cell 11c) is input, and the necessary heat quantity Q is calculated from the following equation (3).
(Equation 3)
Q (cal) = c · W · Δt
= 1 [cal / cc · K] x W [l] x 1000 [cc / l] x (T2-T1) [K]
Here, c is the specific heat of water, and its unit is cal / cc · K. The unit of hot water excess / deficiency W is 1 (liter), Δt is the difference between the fuel cell cooling water outlet temperature T2 and the fuel cell cooling water inlet temperature T1, and the unit is K (Kelvin).

  The fuel cell cooling water inlet temperature T1 and the fuel cell cooling water outlet temperature T2 are respectively derived from the fuel cell cooling water inlet temperature detection unit 48 and the fuel cell cooling water outlet temperature detection unit 49 to the heat quantity calculation unit 51 described above. It is like that.

Next, the work amount W for obtaining the calculated necessary heat quantity Q is calculated from the following equation (4).
(Equation 4)
W (J) = J · Q = 4.19 [J / cal] × Q [cal]
Here, J is the work equivalent of heat and is 4.19, and its unit is J / cal. The unit of work W is Joule (J), which is different from J, the work equivalent of heat.

Then, the work rate P is calculated from the following formula 5 from the input time Ta until the hot water demand peak time and the calculated work amount W.
(Equation 5)
P (W) = W / Ta
Here, the unit of work rate P is watts (W), and the unit of time Ta is seconds (s).

The power generation control device 40 includes a power generation correction amount calculation unit 52 that inputs a heat amount per unit time (work rate, that is, power P) from the heat amount calculation unit 51 per unit time and calculates a power generation correction amount at predetermined time intervals. Yes. This power generation correction amount calculation means 52 takes into account the power generation efficiency of the fuel cell 11c, the heat loss from the hot water storage tank 30 and the cooling water circulation system (the introduction pipe 31, the discharge pipe 32) between the hot water storage tank 30 and the fuel cell 11c. The required power input from the calorific value calculation unit 51 per unit time is corrected and calculated. Specifically, it is calculated from the following formula 6.
(Equation 6)
Power generation correction amount Ph = c1 × (P + c2)
Here, c1 and c2 are set in consideration of the power generation efficiency of the fuel cell 11c and the heat loss from the hot water storage tank 30 or the cooling water circulation system (the introduction pipe 31 and the outlet pipe 32) between the hot water storage tank 30 and the fuel cell 11c. It is a constant.

  The power generation control device 40 inputs the power generation correction amount Ph from the power generation correction amount calculation means 52 and the power consumption Ps in the load device 21 detected by the wattmeter 22 respectively at predetermined time intervals, and generates power necessary for the power generation device 10. An adder 47c for calculating the quantity is provided. Specifically, the adder 47c directly inputs the power consumption Ps from the wattmeter 22 which is power consumption detection means for detecting the power consumption Ps in the load device 21 disposed in the power usage place 20 every predetermined time. Or a value (for example, an average value) calculated based on the past several data including the current power consumption Ps is input. The input power consumption Ps and the power generation correction amount Ph input from the power generation correction amount calculation means 52 are added, and the added value is output to the power generation amount instruction value calculation unit 53.

  Then, the power generation control device 40 calculates a power generation amount instruction value so as to obtain electric power that is an addition value based on the addition value input from the addition unit 47c, and instructs the generator 11 to transmit. The power generation amount instruction value defines the amount of hydrogen gas in the reformed gas supplied to the fuel cell 11c, that is, the amount of fuel and reformed water supplied to the reformer 11a. Therefore, the generator 11 supplies the fuel amount and the reforming water amount to the reforming device 11a according to the power generation amount instruction value, and outputs the power generation amount obtained by adding the power generation correction amount Ph calculated as described above to the power consumption Ps. To do.

  In addition, the calorie calculation unit per unit time described in the claims is the calorie calculation unit 51 per unit time, the power generation correction amount calculation unit is the power generation correction amount calculation unit, and the power consumption detection unit is the wattmeter 22. The power generation amount instruction value calculating means includes an adding unit 47c and a power generation amount instruction value calculating unit 53. The time calculating means until the peak time is the time calculating part 43 until the peak time. The hot water consumption prediction amount calculation unit 44, the hot water supply prediction amount calculation unit 45, and the addition units 47a and 47b are configured. The hot water consumption prediction amount calculation unit is the hot water consumption prediction amount calculation unit 44, and the hot water supply prediction amount calculation unit is This is a predicted hot water supply amount calculation unit 45.

  Next, a power generation control method for the above-described cogeneration system will be described. The power generation control device 40 basically measures the power consumption of the power usage place 20 using the wattmeter 22, stores the measured power consumption in the memory 31, and the power generation device so as to be the same as the power consumption. Power consumption tracking control for tracking 10 output powers is executed. In addition to this power consumption follow-up control, the power generation control device 40 is necessary for each predetermined time by the hot water demand peak time based on the time Ta until the hot water demand peak time and the excess / shortage amount W of hot water at the peak time. The amount of heat Q per unit time is calculated, the amount of power generation Ph required to generate the amount of heat is calculated as a power generation correction amount, and the power consumption Ps in the load device 21 is detected, and the calculated power generation correction amount Ph Based on the detected power consumption Ps, the output power is calculated every predetermined time, and the power generation apparatus 10 is controlled so as to be the output power.

  Specifically, the power generation control device 40 calculates the time Ta until the hot water demand peak time as described above in the time calculation unit 43 until the hot water demand peak time every predetermined time, and calculates the predicted amount of hot water consumption. 44, output to each of the predicted hot water supply amount calculation unit 45 and the heat amount calculation unit 51 per unit time. When the warm water consumption prediction amount calculation unit 44 and the hot water supply prediction amount calculation unit 45 input the time Ta until the hot water demand peak time, respectively, the hot water consumption prediction amount and the warm water supply prediction amount are calculated and added to the addition unit 47a as described above. Output. When the addition unit 47a inputs the predicted hot water consumption amount and the predicted hot water supply amount, as described above, it calculates the remaining amount of hot water at the hot water demand peak time and outputs it to the addition unit 47b. When the remaining amount of hot water at the hot water demand peak time is input, the adding unit 47b calculates the excess / deficiency amount W of hot water as described above and outputs it to the heat amount calculation unit 51 per unit time. When the hot water excess / deficiency W is input, the heat quantity calculation unit 51 calculates the amount of heat Q required from the current time to the hot water demand peak time as described above based on the time Ta until the hot water demand peak time previously input. The amount of heat per unit time, that is, the work rate P is calculated and output to the power generation correction amount calculation unit 52. When the amount of heat per unit time is input, the power generation correction amount calculation unit 52 calculates the power generation correction amount Ph as described above and outputs it to the addition unit 47c. When the power generation correction amount Ph is input, the adding unit 47c calculates the power generation amount instruction value as described above and outputs the power generation amount instruction value to the power generation apparatus 10, that is, the power generator 11. The power generator 11 supplies the amount of fuel and the amount of reformed water to the reformer 11a according to the power generation amount instruction value, and outputs the power generation amount obtained by adding the power generation correction amount Ph to the power consumption Ps.

  As is clear from the above description, in the present embodiment, the hot water demand peak time is reached at predetermined time intervals based on the time Ta until the hot water demand peak time and the excess / shortage amount W of hot water at the peak time. A heat amount P per unit time of the necessary heat amount Q is calculated, and a power generation amount Ph required to generate the heat amount is calculated as a power generation correction amount, and power consumption Ps in the load device 21 is detected, and the calculated power generation correction amount Since the output power is calculated every predetermined time based on Ph and the detected power consumption Ps, and the power generation device 10 is controlled so as to become the output power, the power generation amount is corrected at any time, and the sudden heat load Alternatively, power and heat can be efficiently supplied by performing power generation corresponding to the power load.

  Moreover, since the time Ta until the hot water demand peak time is calculated based on the time when the power generation correction amount Ph is calculated and the power consumption Ps is detected and the hot water demand pattern, the time Ta until the hot water demand peak time is surely determined. Can be calculated.

  Moreover, since the hot water excess / deficiency amount W at the hot water demand peak time is calculated based on the predicted hot water supply amount, the predicted hot water consumption amount, and the remaining hot water amount in the hot water tank, the excess / shortage amount W of hot water at the hot water demand peak time is ensured. Can be calculated.

  Further, since the predicted hot water supply amount is calculated based on the power demand pattern and the time Ta until the hot water demand peak time, the hot water amount supplied by the power generation by the hot water demand peak time can be reliably predicted.

  Moreover, since the predicted amount of hot water consumption is calculated based on the hot water demand pattern and the time Ta until the hot water demand peak time, the amount of hot water consumed by the hot water demand peak time can be reliably predicted.

  In addition, the calorie calculation unit 51 per unit time calculates the amount of heat Q required by the hot water demand peak time based on the time Ta until the hot water demand peak time and the excess / shortage amount W of hot water at the same peak time for each predetermined time. The heat amount P per unit time is calculated, and the power generation correction amount calculation unit 52 calculates the power generation amount Ph necessary for generating the heat amount P per unit time calculated by the heat amount calculation unit 51 per unit time as the power generation correction amount. The power meter 22 detects the power consumption in the load device 21 every predetermined time, and the addition unit 47c and the power generation amount instruction value calculation unit 53 calculate the power generation correction amount Ph calculated by the power generation correction amount calculation unit 52 and the power meter 22. The power generation amount instruction value is calculated on the basis of the power consumption Ps detected by the above and output to the power generation apparatus 10. As a result, the output power is calculated every predetermined time based on the calculated power generation correction amount Ph and the detected power consumption Ps, and the power generation apparatus 10 is controlled so as to be the output power. By performing power generation corresponding to sudden heat load and / or power load with correction as needed, power and heat can be supplied efficiently.

  Further, the time calculation unit 43 up to the peak time calculates the power generation correction amount Ph and calculates the time up to the hot water demand peak time Ta based on the time when the power consumption Ps is detected and the hot water demand pattern. Since the addition unit 47b that finally calculates the excess / deficiency amount calculates the excess / deficiency amount W of hot water at the hot water demand peak time based on the predicted amount of hot water supply, the predicted amount of hot water consumption, and the remaining hot water amount of the hot water tank, The amount of heat P per unit time of the amount of heat Q required before the peak time can be reliably calculated.

  Further, the predicted hot water supply amount calculation unit 45 calculates the predicted hot water supply amount based on the power demand pattern and the time Ta until the hot water demand peak time, and the predicted hot water consumption amount calculation unit 44 calculates the hot water demand pattern and the hot water demand. Since the predicted amount of hot water consumption is calculated based on the time Ta until the peak time, the excess / deficiency amount W of hot water at the hot water demand peak time can be reliably calculated.

It is a schematic diagram showing an outline of an embodiment of a cogeneration system according to the present invention. It is a schematic diagram which shows the generator and hot water storage tank shown in FIG. 1 in detail. FIG. 2 is a schematic diagram showing a block diagram of the power generation control device shown in FIG. 1. It is a figure which shows the warm water demand pattern in a hot water use place. It is a figure which shows the electric power demand pattern in an electric power usage place.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Power generation device, 11 ... Generator, 11a ... Reformer, 11b ... CO reduction device, 11c ... Fuel cell, 12 ... Converter, 13 ... Fuel supply device, 14 ... Water supply device, 15 ... Transmission line, 16 ... system power supply, 17 ... hot water use place, 18 ... hot water heater, 19 ... fuel supply pipe, 19a ... flow meter, 20 ... power use place, 21 ... load device, 22 ... wattmeter, 30 ... hot water tank, 31 ... introduction Pipe, 32 ... Deriving pipe, 33 ... Pump, 34 ... Residual hot water detection sensor, 35 ... Radiator, 36, 37 ... First and second temperature sensors, 38 ... Hot water supply pipe, 39 ... Flow meter, 40 ... Power generation control device 41a, 41b, 41c ... storage unit, 42 ... timer, 43 ... time calculation unit until hot water demand peak time, 44 ... hot water consumption prediction amount calculation unit, 45 ... hot water supply prediction amount calculation unit, 46 ... hot water tank remaining hot water amount Calculation unit, 47a, 47b, 47 DESCRIPTION OF SYMBOLS ... Adder, 48 ... Fuel cell cooling water inlet temperature detection unit, 49 ... Fuel cell cooling water outlet temperature detection unit, 51 ... Heat amount calculation unit per unit time, 52 ... Power generation correction amount calculation unit, 53 ... Power generation amount instruction value calculation Department.

Claims (9)

A power generation control method for a cogeneration system comprising: a power generation device that supplies power to a load device; and a hot water tank that stores hot water heated by heat energy generated during power generation and supplies the stored hot water In
Calculates the amount of heat per unit time required for the hot water demand peak time based on the time until the hot water demand peak time and the excess and deficiency of the hot water at the same peak time every predetermined time, and generates the amount of heat. The power generation amount necessary for the calculation is calculated as a power generation correction amount, and the power consumption in the load device is detected. Based on the power generation correction amount calculated and the detected power consumption, output power is calculated every predetermined time and output A power generation control method for a cogeneration system, wherein the power generation device is controlled to be electric power.   The cogeneration system according to claim 1, wherein the time until the hot water demand peak time is calculated based on the time when the power generation correction amount is calculated and the time when the power consumption is detected and the hot water demand pattern. Power generation control method.   2. The power generation control of a cogeneration system according to claim 1, wherein the excess or deficiency amount of hot water at the hot water demand peak time is calculated based on a predicted hot water supply amount, a predicted hot water consumption amount, and a remaining hot water amount in the hot water storage tank. Method.   4. The power generation control method for a cogeneration system according to claim 3, wherein the predicted hot water supply amount is calculated based on a power demand pattern and a time until the hot water demand peak time.   4. The power generation control method for a cogeneration system according to claim 3, wherein the predicted hot water consumption amount is calculated based on a hot water demand pattern and a time until the hot water demand peak time. Controls the power generation of a cogeneration system that includes a power generation device that supplies power to the load device and a hot water tank that stores hot water heated by the thermal energy generated during power generation and supplies the stored hot water In the power generation control device to
Calorie calculation means per unit time for calculating the calorific value per unit time of the amount of heat required by the hot water demand peak time based on the time to the hot water demand peak time and the excess / deficiency amount of hot water at the peak time at predetermined time intervals When,
A power generation correction amount calculating means for calculating a power generation amount necessary for generating the heat per unit time calculated by the heat amount calculating means per unit time as a power generation correction amount;
Power consumption detection means for detecting power consumption in the load device every predetermined time;
A power generation amount instruction value calculation unit that calculates a power generation amount instruction value based on the power generation correction amount calculated by the power generation correction amount calculation unit and the power consumption detected by the power consumption detection unit and outputs the power generation amount instruction value to the power generation device; A power generation control device for a cogeneration system, comprising:   7. The peak time according to claim 6, wherein the calorie calculation unit per unit time calculates the power generation correction amount and calculates the time to the hot water demand peak time based on the time when the power consumption is detected and the hot water demand pattern. Time calculation means, and hot water excess / deficiency calculation means for calculating an excess / deficiency amount of hot water at the hot water demand peak time based on a predicted amount of hot water supply, an estimated amount of hot water consumption, and a remaining hot water amount in the hot water storage tank A power generation control device for a cogeneration system.   8. The hot water supply / deficient amount calculation means according to claim 7, wherein the hot water supply predicted amount calculation means calculates the hot water supply predicted amount based on a power demand pattern and a time until the hot water demand peak time, and a hot water demand pattern. And a hot water consumption predicted amount calculation means for calculating the hot water consumption predicted amount based on the time until the hot water demand peak time, a power generation control device for a cogeneration system. A power generation device that supplies power to the load device, a hot water tank that stores hot water heated by thermal energy generated during power generation, and that supplies the stored hot water, and power generation that controls power generation of the power generation device In a cogeneration system equipped with a control device,
The power generation control device
Calorie calculation means per unit time for calculating the calorific value per unit time of the amount of heat required by the hot water demand peak time based on the time to the hot water demand peak time and the excess / deficiency amount of hot water at the peak time at predetermined time intervals When,
A power generation correction amount calculating means for calculating a power generation amount necessary for generating the heat per unit time calculated by the heat amount calculating means per unit time as a power generation correction amount;
Power consumption detection means for detecting power consumption in the load device every predetermined time;
A power generation amount instruction value calculation unit that calculates a power generation amount instruction value based on the power generation correction amount calculated by the power generation correction amount calculation unit and the power consumption detected by the power consumption detection unit and outputs the power generation amount instruction value to the power generation device; Cogeneration system characterized by having

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