JP2003269736A - Cogeneration system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cogeneration system operable for lowering energy costs related to hot-water supply. <P>SOLUTION: This cogeneration system is provided with a tank water supply means Wb feeding water to a hot-water tank 3, an exhaust heat recovering circulation means Ce circulating hot water through an exhaust heat recovering heat exchanger 2 and the hot-water tank 3, and a hot-water supplying circulation means Cs circulating hot water between the hot-water tank 3 and a hot-water circulation passage 14 through a plurality of houses H. An operation control means can freely switch an operation condition between a circulating operation condition, in which a water supplying operation of the tank water supply means Wb and a hot-water circulating operation by the exhaust heat recovering circulation means Ce are stopped while a hot-water circulating operation of the hot-water supplying circulation means Cs is carried out during a power generation stopping time in which an operation of a power generation means 1 is stopped, and a circulation stopping operation condition, in which water supplying operation of the tank water supply means Wb, the hot-water circulating operation of the exhaust heat recovering circulation means Ce, and the hot-water circulating operation of the hot-water supply circulation means Cs are stopped. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power generation means for generating electric power in an area or an apartment house as an electric power supply target, a heat exchanger for recovering exhaust heat supplied with the exhaust heat from the electricity generation means, and the area or apartment house. A hot water storage tank that stores hot water for a plurality of dwelling units included, hot water supply means for supplying water to the hot water storage tank, exhaust heat recovery circulation for circulating hot water between the exhaust heat recovery heat exchanger and the hot water storage tank Means, hot water supply circulation means for circulating hot water in a hot water supply circulation path extending between the hot water storage tank and the plurality of dwelling units, dwelling unit water supply means for supplying water to each of the plurality of dwelling units, and operation control means for controlling operation And a water heater that supplies hot water to the hot water demand section with hot water supplied through the hot water supply circulation means and water supplied through the dwelling water supply means, respectively. On the cogeneration system.

[0002]

2. Description of the Related Art Such a cogeneration system supplies electric power to a plurality of dwelling units (hereinafter may be referred to as a group of dwelling units to be supplied) included in an area or an apartment house by power generation means, and recovers exhaust heat. The circulating means for heating heats the hot water in the hot water storage tank by circulating hot water between the heat exchanger for collecting exhaust heat to which the exhaust heat of the power generating means is supplied and the hot water storage tank, and the hot water circulating means supplies the hot water to the hot water storage tank. By circulating hot water in the hot water supply circulation path to the target dwelling unit group, the exhaust heat of the power generation means is recovered and heated hot water is supplied to the target dwelling unit group, and in each dwelling unit, the hot water supply circulation means is used. The hot water supplied and the water supplied through the dwelling unit water supply means are used to supply hot water to a hot water demand section such as a hot water tap with a water heater. For example, when the temperature of the hot water supplied by the hot water circulation means is equal to or higher than the target hot water supply temperature set by the water heater, the heating operation of the heating means of the water heater is stopped and the hot water demand section is directly connected. When the temperature of the hot water supplied by the hot water supply circulation means is lower than the target hot water supply temperature set by the water heater, the hot water supplied by the hot water supply circulation means is the target hot water temperature. Is heated by the heating means to supply hot water to the hot water demand section. And in such a cogeneration system, in many cases, instead of continuously operating the power generation means, for example,
It operates intermittently, such as operating every day for a set period of time and stopping at other times in response to the time of day when power demand is high. By doing so, the service life of the power generation means can be extended. Therefore, when the power generation is stopped, there is no generation of exhaust heat from the power generation means, so that the heating of the hot water in the hot water storage tank by the exhaust heat of the power generation means is stopped.

In such a cogeneration system, conventionally, for example, as shown in FIG.
Is configured as a closed type, and the tank water supply means Wb is configured by a water supply path 71 that supplies water from the tap water to the hot water storage tank 3 by tap water pressure, and the hot water storage tank 3 is always filled with hot water. The hot water supply circulation means Cs is configured to store the hot water supply circulation path 14
And a hot water supply circulation pump 73 provided in the hot water supply circulation path 14, and the exhaust heat recovery circulation means Ce is the hot water storage tank 3
And the exhaust heat recovery heat exchanger 2 to form a circulation path for exhaust heat recovery, and the exhaust heat recovery circulation path 7
The exhaust heat recovery circulation pump 75 provided in No. 4 is disclosed (see, for example, JP-A-7-324809). In FIG. 11, K is a water heater provided in each dwelling unit in order to heat the hot water supplied by the hot water supply circulation means Cs and supply the hot water to a hot water demand part such as a hot water tap.

In the conventional cogeneration system shown in FIG. 11, by operating the exhaust heat recovery circulation pump 75, the exhaust heat recovery circulation means Ce is operated to circulate hot water, and the hot water supply circulation pump 73 is operated. As a result, the hot water supply circulation means Cs is operated to circulate the hot water, so that the operation control means U uses the exhaust heat recovery circulation pump 7
5 and a circulating pump 73 for hot water supply.
Then, in the conventional cogeneration system shown in FIG. 11, when power generation is stopped by stopping the operation of the power generation means, the tank water supply means Wb always supplies hot water to the hot water storage tank 3 so as to store hot water in a full state. It is conceivable that the operation control means U is configured to constantly stop the hot water circulation operation of the exhaust heat recovery circulation means Ce and operate the hot water supply circulation means Cs to perform the hot water circulation operation.

[0005]

Conventionally, when the power generation is stopped, the tank water supply means always supplies the hot water to the hot water storage tank so that the hot water is stored in the hot water storage tank while the hot water supply circulation means is always supplied with hot water. When operated so that the circulating operation is performed, the hot water is supplied to the hot water tank so that the hot water tank is filled with water, and the hot water in the hot water tank is constantly circulated for hot water supply even though the hot water is not heated by the exhaust heat of the power generation means. Since the amount of heat radiated during the circulation through the route and the circulation route for hot water supply is large, the temperature drop of the hot water in the hot water storage tank becomes large. Therefore, since the temperature of the hot water supplied to each dwelling unit by the hot water supply circulation means becomes low, the heating amount by the heating means of the water heater for supplying hot water at the target hot water supply temperature in each dwelling unit (hereinafter referred to as additional heating amount). However, there is room for improvement in reducing the energy cost related to hot water supply.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a cogeneration system which can be operated so as to reduce the energy cost related to hot water supply.

[0007]

Means for Solving the Problems [Invention of Claim 1]
The characteristic configuration according to claim 1, wherein the operation control means, when power generation is stopped when the operation of the power generation means is stopped, a water supply operation of the tank water supply means and a hot water circulation operation of the exhaust heat recovery circulation means. And a circulation operation state in which the hot water supply circulation means is operated to perform hot water circulation operation, a water supply operation of the tank water supply means, a hot water circulation operation of the exhaust heat recovery circulation means, and a hot water circulation operation of the hot water supply circulation means. It is configured so that the operation state can be switched between the circulation stop operation state in which it is stopped. According to the characterizing feature of claim 1, when the operation control means switches the operation state to the circulation operation state, the water supply operation of the tank water supply means and the hot water circulation operation of the exhaust heat recovery circulation means are stopped. When the hot water in the hot water storage tank circulates through the hot water supply circulation path and the operating state is switched to the circulation stop operation state, the water supply operation of the tank water supply means and the hot water circulation operation of the exhaust heat recovery circulation means are stopped, and the hot water supply circulation The circulation of hot water in the hot water storage tank through the route is also stopped. In other words, in the circulation operation state, the hot water of the hot water tank circulates through the hot water circulation path in a state where the water supply operation of the water tank supply means is stopped. In a dwelling unit, it is possible to supply hot water using hot water from a hot water storage tank that circulates in the hot water supply circulation path, while in the circulation stop operation state, the water supply operation of the tank water supply means is stopped and the hot water supply circulation path Since the circulation of hot water in the hot water storage tank also stops, the water supply to the hot water storage tank is stopped, and the heat release from the hot water circulation cycle is stopped during the hot water circulation. Can be effectively suppressed. By the way, while operating in the circulation stop operation state, the circulation of hot water in the hot water storage tank through the hot water supply circulation path stops, so in each dwelling unit, using the water supplied by the dwelling unit water supply means, Hot water will be supplied by the water heater. That is, the usage amount of hot water circulated by the hot water supply circulation means in the supply target dwelling unit (hereinafter, may be referred to as circulating hot water usage amount) is different for each time zone of the day, for example. It usually changes over time. Therefore, at the time of power generation stop, when the circulating hot water usage is small, the circulating hot water operation is performed in the stopped state, and when the circulating hot water usage is high, the circulating hot water is used to operate in the circulating state. It is possible to reduce the amount of additional heating when hot water is supplied by the water heater when power generation is stopped. In other words, when hot water is supplied to each dwelling unit in the supply target dwelling unit by operating in the circulation stop operation state,
Even if only the water from the dwelling unit water supply means is used instead of the hot water in the hot water storage tank, the operation in the circulation stop operation state can suppress the temperature drop of the hot water in the hot water storage tank as much as possible, and the circulation operation When operating in this state, hot water as hot as possible can be supplied to the supply target dwelling unit group, and the amount of additional heating in the water heater of each dwelling unit is minimized.
Then, the increase in the additional heating amount during the operation in the circulation stopped operation state is increased by the additional heating during the operation in the circulation operation state by suppressing the temperature decrease of the hot water tank by the operation in the circulation stop operation state. It is possible to make the amount smaller than the decrease in the amount, and it is possible to reduce the additional heating amount in the hot water supply by the water heater at the time of power generation for the entire supply target dwelling unit group. By the way, when the power generation means is operated in a time zone with a large power demand (for example, from 18:00 to 2:00 the next day), a time zone toward the end of the time zone with a large power demand (for example, During the period from 0:00 to 2:00), the demand for hot water is generally low and the amount of circulating hot water used is small, so the hot water temperature in the hot water storage tank is kept high (for example, about 50 to 60 ° C). Thus, it is possible to stop the power generation. Then, at the time of power generation stop starting at 2 o'clock, since the demand for hot water is small during the start time period (for example, between 2 o'clock and 6 o'clock), when operating in the circulation stop operation state during that time period, Since the temperature of the hot water in the hot water storage tank is maintained at a high temperature when the power generation means is stopped, at the time of starting the operation in the circulation operation state, the temperature at which hot water in the hot water storage tank does not need to be heated is almost unnecessary.
(For example, about 45 ° C.) can be maintained, and the amount of additional heating can be effectively reduced. or,
When the operation state is switched to the circulation stop operation state, the hot water circulation operation of the hot water supply circulation means is stopped, so that the energy consumption for driving the hot water supply circulation means can be reduced. Therefore, the amount of additional heating can be reduced, and the energy consumption for driving the hot water supply circulation means can be reduced, so that the operation cost can be reduced so that the energy cost for hot water supply can be reduced. It is now possible to provide a generation system.

[Invention of Claim 2] The characteristic configuration according to Claim 2 is provided with a determination means for determining a usage state of hot water circulated by the hot water circulation means in the plurality of dwelling units, The operation control means is configured to automatically switch the operation state between the circulation operation state and the circulation stop operation state based on the determination information of the determination means. According to the characteristic configuration of claim 2, the determining means determines the usage state of the hot water circulating in the hot water circulating means in the plurality of dwelling units (hereinafter, may be referred to as the circulating hot water usage state). The operation control means automatically switches the operating state between the circulating operating state and the circulating stop operating state based on the result of the determination of the circulating hot and cold water usage state of the determining means. That is, when the determination means determines that the circulating hot water usage is low,
When the operation control unit operates in the circulation stop operation state, and when the determination unit determines that the circulation hot water usage amount is large, the operation control unit operates in the circulation operation state. In addition, it becomes possible to drive. Therefore, the operating state is automatically switched to operate so that the energy cost related to hot water supply can be reduced,
It has become possible to provide a cogeneration system that is even easier to use.

[Invention of Claim 3] The characteristic configuration according to Claim 3 is that the operation control means is configured such that, in the circulation operation state, when the amount of hot water stored in the hot water storage tank is equal to or less than a set lower limit amount. Is configured to control the water supply operation of the tank water supply means so as to maintain the hot water storage amount at the set lower limit amount. According to the characteristic configuration of claim 3, in the circulation operation state, when the amount of hot water stored in the hot water storage tank becomes equal to or lower than the set lower limit amount, the tank water supply means of the tank water supply means is maintained so as to maintain the hot water storage amount at the set lower limit amount. The water supply operation is controlled. In other words, when power generation is stopped, there is no generation of exhaust heat from the power generation means and heating of the hot water in the hot water storage tank is stopped.
Even if water supply by the water supply means for the bath is stopped in order to suppress the temperature drop of the hot water in the hot water storage tank, if the hot water storage amount in the hot water storage tank becomes low and falls below the set lower limit amount, the hot water storage amount is set at the lower limit amount. Since the water is supplied so as to maintain the hot water in the hot water storage tank, it is possible to operate the hot water storage tank without running out of water from the hot water storage tank to the supply target dwelling unit group. Therefore, when power generation is stopped, hot water supply from the hot water storage tank to the target dwelling unit group is not interrupted during times when hot water demand is high, while cogeneration that can be operated to reduce energy costs related to hot water supply. The system can now be provided.

[Invention of Claim 4] The feature configuration of Claim 4 is that the water heater mixes hot water supplied through the hot water circulation means with water supplied through the dwelling unit water supply means. Alternatively, the hot water is supplied at the target hot water supply temperature by heating by the heating means.
According to the characteristic configuration of claim 4, the hot water supply device mixes the hot water supplied through the hot water supply circulation means with the water supplied through the dwelling unit water supply means or heats the heating means at the target hot water supply temperature. Hot water is supplied to the hot water demand department. That is, when the temperature of the hot water supplied through the hot water supply circulation means is higher than the target hot water supply temperature, the hot water supplied through the hot water supply circulation means and the water supplied through the dwelling unit water supply means are adjusted to reach the target hot water supply temperature. And are mixed, and when the temperature of the hot water supplied through the hot water supply circulation means is lower than the target hot water supply temperature, the heating means heats the hot water to the target hot water supply temperature. Therefore, it is possible to provide a cogeneration system that can be operated so as to reduce the energy cost related to hot water supply and that is supplied with hot water at the target hot water supply temperature and is easy to use.

[Invention of Claim 5] The feature of claim 5 is that, when the power generation is stopped, the supply amount or heat amount of the hot water supplied to the plurality of dwelling units through the hot water supply circulation means is used as a heat load. A heat load detection unit for detecting and a storage unit for storing the heat load detected by the heat load detection unit are provided, and the determination unit is configured to perform the power generation on the operation target day based on the storage information of the storage unit. It is configured to include a heat load predicting means for predicting a heat load at the time of stop, and the operation control means, based on the prediction information of the heat load predicting means, an operating state in the circulation operating state and the circulation stop operating state. Is configured to switch.
According to the characteristic configuration of claim 5, the heat load detection means detects the supply amount or heat quantity of the hot water supplied to the plurality of dwelling units through the hot water supply circulation means as the heat load, and thus the heat load detection is performed. The heat load detected by the means is stored in the storage means. Then, the heat load prediction means constituting the determination means predicts the heat load on the operation target day based on the storage information of the storage means, and the operation control means based on the prediction information of the heat load prediction means, the circulation operation. The operating state is automatically switched between the state and the circulation stop operating state. That is, the circulating hot water usage state can be determined by the amount of hot water supplied to the plurality of dwelling units through the hot water circulating means or the amount of heat. Therefore, the heat load detecting means detects the supply amount or heat quantity of the hot water supplied to the plurality of dwelling units through the hot water supply circulating means as the heat load, and the heat load detected by the heat load detecting means is stored in this way. The heat load predicting means predicts the heat load on the operation target day based on the stored information in the storage means. Then, by the operation control means, when power generation is stopped, based on the prediction information of the heat load prediction means, it is possible to reduce the amount of additional heating in hot water supply by the water heater in the supply target dwelling unit group so that the circulation operation can be reduced. It is possible to switch the operating state between the state and the circulation stop operating state. By the way, the determination means is configured with a timekeeping means for timing the time, and the low hot water supply load time zone at the time of power generation stop, where the circulating hot water usage is expected to be small, is set in advance, and the timekeeping information of the timekeeping means is set. On the basis of this, the circulating hot water use state is determined whether the circulating hot water use amount is large or small by discriminating between the inside and outside of the low hot water supply load time period at the time of power generation stop, and the operation control means based on the discrimination information. Therefore, it may be possible to switch the operating state between the circulation operating state and the circulation stopped operating state. Then, in switching the operation state between the circulation operation state and the circulation stop operation state,
When the heat load on the operation target day is predicted and the operating state is switched based on the predicted heat load as in the characteristic configuration of claim 5, the low hot water supply load time zone at the time of power generation stop is set as described above. Compared to the case where the operating state is uniquely set and the operating state is switched uniquely depending on the time zone, the operating state can be appropriately changed to the circulating operating state and the circulating stop operating state according to the actual circulating hot water use state. Can be switched, and the effect of reducing the additional heating amount can be further promoted. Therefore, it has become possible to provide a cogeneration system that can be operated so that the energy cost related to hot water supply can be further reduced.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the cogeneration system includes a generator 1 as a power generation unit that generates electric power from an apartment house as an electric power supply target, an exhaust heat recovery heat exchanger 2 to which exhaust heat from the generator 1 is supplied, A hot water storage tank 3 that stores hot water for a plurality of dwelling units H included in an apartment, hot water supply means Wb for supplying water to the hot water storage tank 3, a heat exchanger 2 for recovering exhaust heat, and a hot water storage tank 3.
Exhaust heat recovery circulation means C for circulating hot water over
e, a hot water supply circulation means Cs for circulating hot water in the hot water supply circulation path 14 extending over the hot water storage tank 3 and the plurality of dwelling units H included in the housing complex, and for dwelling units supplying water to each of the plurality of dwelling units H included in the dwelling house The water supply means Ws and the operation control means U for controlling the operation of the cogeneration system are provided, and hot water supplied through the hot water circulation means Cs is used for each of the plurality of dwelling units H included in the housing complex. A water heater K for supplying to each hot and cold water demanding unit in H is provided and configured.

Further, the cogeneration system is provided with a power receiving and transforming facility 61 for collectively receiving the electric power from the commercial power source 62, and an interconnecting device 63 for interconnecting the generator 1 with the commercial power source 62 to generate power. The power supply line 6 so that the electric power from the machine 1 and the commercial power source 62 is supplied to each dwelling unit H included in the housing complex and the shared power consumption device 64 in the housing complex.
5 is wired. Hereinafter, the power consumption devices in the plurality of dwelling units H included in the housing complex and the shared power consumption device 64 in the housing complex may be collectively referred to as an external power load. In addition, a collective power receiving power meter M6 for measuring the power received by the power receiving and transforming equipment 61 is provided, and a power supply line 65 to each dwelling unit H includes a dwelling unit power meter M7 for measuring the power received by each dwelling unit H. It is provided. The power from the generator 1 may be supplied to the shared power consumption device 64, and the power from the commercial power source 62 may be supplied to each dwelling unit H without being collectively received.

In the present invention, the operation control means U activates the exhaust heat recovery circulation means Ce and the hot water supply circulation means Cs to circulate the hot water in the hot water storage tank 3 during the power generation of the generator 1. The normal operation state in which the water supply operation of the tank water supply means Wb is controlled so that the stored amount becomes equal to or larger than the set reference amount, and the exhaust heat recovery circulation means Ce and the hot water supply circulation means Cs are circulated in hot water and the hot water storage tank 3 is operated. The operation state is switched to the temperature reduction suppressing operation state in which the control of the water supply operation of the tank water supply means Wb for making the hot water storage amount equal to or more than the set reference amount is stopped, and the operation of the generator 1 is stopped. When the power generation is stopped, the circulation operation state in which the water supply operation of the tank water supply means Wb and the hot water circulation operation of the exhaust heat recovery circulation means Ce are stopped and the hot water supply circulation means Cs is operated for hot water circulation, and the tank water supply means Wb Salary Operation, and it is configured to switch the operation state to the circulation shutdown state to stop the hot water circulation operation of hot water circulation operation and the hot water circulation unit Cs of the exhaust heat recovery circulating means Ce.

Further, the operation control means U comprises a controller 5 utilizing a microcomputer, and is in a state of use of hot water circulated by the hot water supply circulation means Cs in the housing units to be supplied, that is, circulating hot water. A discriminating means D for discriminating the usage state is provided. And the operation control means U
Is configured to use the controller 5 to automatically switch the operating state between the normal operating state, the temperature reduction suppressing operating state, the circulating operating state, and the circulating stopped operating state based on the determination result of the determining means D. .

Further, the operation control means U sets the hot and cold water storage amount to the set lower limit amount when the hot and cold water storage amount in the hot water storage tank 3 becomes equal to or lower than the set lower limit amount which is smaller than the set reference amount in the temperature reduction suppressing operation state. In order to maintain it, the water supply operation of the tank water supply means Wb is controlled. Also, the operation control means U
In the circulation operation state, when the amount of hot and cold water stored in the hot water storage tank 3 is less than or equal to the set lower limit amount, the water supply operation of the tank water supply means Wb is controlled so as to maintain the amount of hot and cold water storage at the set lower limit amount. It is configured as follows.

The generator 1 is equipped with a gas engine (not shown) that uses city gas as a fuel supplied through the generator gas supply path 6 and is of a rotary type that is driven by the gas engine. M1 in the figure is a gas supply path 6 for the generator
It is a common-use gas flow meter provided in the, and measures the gas consumption in the generator 1. The engine cooling water for cooling the gas engine is circulated in the cooling water circulation path 7 between the gas engine and the exhaust heat recovery heat exchanger 2. Reference numeral 8 in the drawing denotes a cooling water circulation pump provided in the cooling water circulation passage 7.

The hot water storage tank 3 is an open type, and the hot water storage tank 3 is
A hot water storage temperature sensor 10 as hot water storage temperature detecting means for detecting the temperature of hot water to be stored, and a water level sensor 9 for detecting the water level to be stored are provided.

The circulation means Ce for recovering exhaust heat is a pipe for recovering exhaust heat, which is arranged to flow hot water taken out from the bottom of the hot water storage tank 3 through the heat exchanger 2 for recovering exhaust heat from the upper part of the hot water storage tank 3. A circulation path 11 and an exhaust heat recovery circulation pump 13 provided in the exhaust heat recovery circulation path 11 are provided.
That is, when the exhaust heat recovery circulation pump 13 is operated, the exhaust heat recovery circulation means Ce operates to circulate hot water, and hot water flows through the exhaust heat recovery circulation path 11 into the hot water storage tank 3 and the exhaust heat recovery heat exchanger 2. Circulation pump 13 for exhaust heat recovery
When the operation of is stopped, the hot water circulation operation of the exhaust heat recovery circulation means Ce is stopped.

The tank water supply means Wb is a tank water supply channel 4 connected to the hot water storage tank 3 as a water supply source, and a tank for intermittently supplying water to the hot water storage tank 3 provided in the tank water supply channel 4. The water supply passage opening / closing valve V1 is provided. That is, when the tank water supply passage opening / closing valve V1 is opened, the tank water supply means Wb operates to supply water, tap water is supplied to the hot water storage tank 3 through the tank water supply passage 4, and the tank water supply passage opening / closing valve V1 is closed. When the valve is opened, the water supply operation of the tank water supply means Wb is stopped.

The hot water supply circulation means Cs is a circulation path for hot water supply which is arranged to flow hot water taken out from the bottom of the hot water storage tank 3 back to the upper part of the hot water storage tank 3 via a plurality of dwelling units H included in the housing complex. 14, a hot water supply circulation pump 15 provided upstream of the dwell unit passage point in the hot water supply circulation route 14, and a hot water supply circulation route opening / closing valve V2 provided downstream of the dwell unit passage point in the hot water supply circulation route 14. Each of the dwelling units H is connected with a dwelling unit hot water supply passage 17 for supplying hot water flowing through the hot water supply circulation route 14 to each dwelling unit H. That is, the hot water supply circulation path opening / closing valve V2 is opened,
When the hot water supply circulation pump 15 is operated, the hot water supply circulation means Cs performs hot water circulation operation, and hot water circulates through the hot water supply circulation path 14 between the hot water storage tank 3 and the plurality of dwelling units H, and the hot water supply circulation path open / close valve V2. Circulating pump 15 for hot water supply
When the operation of is stopped, the hot water circulation operation of the hot water supply circulation means Cs is stopped.

The dwelling unit water supply means Ws comprises a dwelling unit water supply channel 16 connected to the water supply and each of the plurality of dwelling units H. To each dwelling unit H, a dwelling unit gas supply path 18 for supplying city gas is connected. In each dwelling unit H, the hot water supply passage 17 for the dwelling unit is connected to the water heater K, and the water feed passage 16 for the dwelling unit is connected to the water heater K and a water consuming part such as a water tap of a washroom or a kitchen, for dwelling units. The gas supply passage 18 is connected to a water consuming unit such as a water heater K and a gas stove, and hot water supplied through the hot water circulating means Cs and water supply means Ws for dwelling units.
It is configured to supply hot water to the hot water demand section using the water supplied through.

A common tap water flow meter M2 for measuring the amount of water supplied to the hot water storage tank 3 is provided in the tank water supply passage 4, and is supplied to the dwell unit hot water supply passage 17 by the hot water circulation means Cs. A hot water flow meter M3 for measuring the flow rate of hot water is provided, a dwell unit gas supply channel 18 is provided with a dwell unit gas flow meter M4, and a dwell unit water supply channel 16 is provided with a dwell unit tap water flow meter M5.

Next, the control operation of the controller 5 will be described. First, power supply control for supplying power to the target dwelling unit group and the shared power consumption device 64 by the generator 1 and the commercial power supply 62 will be described. The controller 5 operates the generator 1 in a predetermined time zone for one day (for example, 8 hours from 18:00 to 2:00, which is set as a time zone in which power demand is high), and other time zones The generator 1 is automatically operated every day so as to stop the generator 1. Then, while the generator 1 is in operation, the generator 1 is supplied with power to the external power load, and when the output of the generator 1 is insufficient with respect to the external power load, the shortage is supplied to the commercial power source. Supplemented at 62. or,
When the generator 1 is stopped, the commercial power source 6 is supplied to the external power load.
Power is supplied at 2.

Next, the hot water supply control for supplying the hot and cold water of the hot water storage tank 3 to the group of dwelling units to be supplied will be described with reference to FIGS. 5 to 9. During power generation, the determining means D determines a circulating hot water use state in which the temperature of the hot water in the hot water storage tank 3 is greatly lowered, and the hot water storage temperature lowering state is a state in which the hot water storage state should be switched from the normal operating state to the temperature reduction suppressing operating state, and The hot water storage temperature rise state, which is the state in which the temperature decrease control operation state should be switched to the normal operation state after the temperature decrease of the hot and cold water in the tank 3 is eliminated, and when the power generation is stopped, the circulating hot water use state is used. High hot water supply load condition when power generation is stopped, which is a condition where the circulation operation condition is to be executed, and low hot water supply load when power generation is stopped, which is a condition where the circulating hot water use amount is low and the circulation stop operation condition is to be executed It is configured to determine the state.

By the way, the hot water storage temperature lowered state means that the hot and cold water consumption amount in the dwelling unit group to be supplied during operation in the normal operation state,
That is, the circulating hot water usage increases and the temperature of the hot and cold water in the hot water storage tank 3 tends to decrease, and the hot water storage temperature rising state is set in correspondence with the state in which it is necessary to suppress the decrease. This is set in correspondence with a state in which the amount of circulating hot and cold water used decreases and the temperature of hot and cold water in the hot water storage tank 3 tends to rise during operation in this state, and the rise must be stopped. In addition, in each of the high hot water supply load state during power generation stop and the low hot water supply load state during power generation stop, the circulating hot water usage is higher in the high power supply load state during power generation stop than in the low hot water supply load state during power generation stop. Set.

The controller 5 is supplied with the detection information of the water level sensor 9, the hot water storage temperature sensor 10 and the hot water flow meter M3, respectively, and based on the input information, the cooling water circulation pump 8, the exhaust heat recovery circulation pump 13 and the hot water supply. Circulation pump 1
It is configured to perform start / stop control of each of the five, and open / close control of each of the tank water supply passage opening / closing valve V1 and the hot water supply circulation passage opening / closing valve V2. Further, the storage unit 5m of the controller 5 presets and stores a set reference water level corresponding to the set reference amount and a set lower limit water level corresponding to the set lower limit amount. By the way, as the set reference amount, for example, a storage amount which is slightly smaller than that in a full state is set, and as the set lower limit amount, for example, even when the circulating hot water usage amount increases rapidly, the storage amount in the hot water storage tank 3 becomes zero. Therefore, the lower limit value of the storage amount is set so that hot water can be stably supplied from the hot water storage tank 3 without being interrupted to the supply target dwelling unit group.

The controller 5 executes the normal operation state with the start of the operation of the generator 1, and when the generator 1 is generating electric power, the discriminating means D determines when the normal operation state is being executed. When the hot water storage temperature lowering state is determined, the normal operation state is switched to the temperature reduction suppressing operating state, and when the determining means D determines the hot water storage temperature increasing state while executing the temperature lowering suppression operating state, the temperature reduction suppressing operating state is changed to the normal state. When the power generation is stopped by switching to the operating state and the operation of the generator 1 is stopped, when the determination unit D determines the low hot water supply load state when the power generation is stopped, the operation is performed in the circulation stop operation state and the determination unit D is when the power generation is stopped. When the high hot water supply load state is determined, the operation is performed in the circulation operation state. In addition, the controller 5 communicates the circulation stop operation start information to the water heater K of each dwelling unit H with the start of the operation in the circulation stop operation state, and stops the operation in the circulation stop operation state. As a result, the circulation stop operation end information is communicated.

During power generation, the controller 5 switches the operating state to the exhaust heat recovery stop operating state when the temperature of the hot water in the hot water storage tank 3 becomes equal to or higher than the set upper limit temperature based on the detection information of the hot water storage temperature sensor 10. When the temperature of the hot water in the hot water storage tank 3 becomes lower than the set upper limit temperature, the original operating state is switched to.

Further, when the controller 5 is instructed to execute the inspection operation from the operation unit 22, the controller 5 stops the operation of the generator 1 and, regardless of the determination result of the determination means D, operates in the circulation stop operation state. Switch.

The control operation in each operating state will be described below with reference to FIGS. 5 to 9. In the normal operation state, the cooling water circulation pump 8 is operated, the exhaust heat recovery circulation pump 13 is operated, and the exhaust heat recovery circulation means Ce is operated.
On the basis of the detection information from the water level sensor 9 and the hot water supply circulation passage opening / closing valve V2 is opened and the hot water supply circulation pump 15 is operated to operate the hot water supply circulation means Cs. The tank water supply passage opening / closing valve V1 is controlled to be opened / closed so that the hot water storage water level of the hot water storage tank 3 is maintained at the set reference water level, and the water supply operation of the tank water supply means Wb is interrupted.

As shown in FIG. 5, in the normal operation state, the engine cooling water circulates through the exhaust heat recovery heat exchanger 2, and the hot and cold water in the hot water storage tank 3 flows through the exhaust heat recovery circulation path 11. It circulates through the heat exchanger 2 for recovering exhaust heat, and circulates through a plurality of dwelling units H in the hot water supply circulation path 14 so that the hot water storage water level of the hot water storage tank 3 is maintained at the set reference water level. ,
Water is supplied to the hot water storage tank 3 through the tank water supply passage 4. That is,
The hot and cold water extracted from the hot water storage tank 3 is a heat exchanger 2 for recovering exhaust heat.
By being heated and returned by the heat exchange action with the engine cooling water in, the hot water in the hot water storage tank 3 is heated, and the hot water taken out from the hot water storage tank 3 circulates over a plurality of dwelling units H, and in each dwelling unit H. Is to be supplied by the water heater K using hot water circulating in the hot water supply circulation path 14.

In the temperature reduction suppression operation state, the cooling water circulation pump 8 is operated, the exhaust heat recovery circulation pump 13 is operated, and the exhaust heat recovery circulation means Ce is operated in hot water circulation.
The hot water supply circulation path opening / closing valve V2 is opened and the hot water supply circulation pump 15 is operated, the hot water supply circulation means Cs is operated for hot and cold water circulation, and based on the detection information of the water level sensor 9,
Even when the hot and cold water storage level of the hot water storage tank 3 becomes lower than the set reference water level, the hot water storage tank 3 is maintained in a state in which the closed state of the water supply channel opening / closing valve V1 for the tank is maintained and the water supply operation of the water supply means Wb for the tank is stopped.
When the hot water storage water level becomes equal to or lower than the set lower limit water level, the tank water supply passage opening / closing valve V1 is opened / closed so that the hot water storage water level is maintained at the set lower limit water level, and the water supply operation of the tank water supply means Wb is interrupted.

As shown in FIG. 6, in the temperature reduction suppressing operation state, the engine cooling water circulates through the exhaust heat recovery heat exchanger 2 and the hot and cold water in the hot water storage tank 3 becomes the same as in the normal operation state.
It circulates through the exhaust heat recovery circulation path 11 through the exhaust heat recovery heat exchanger 2, and circulates through a plurality of dwelling units H through the hot water supply circulation path 14, but the amount of hot and cold water stored in the hot water storage tank 3 Even when the amount is less than the set reference amount, the water supply to the hot water storage tank 3 is still stopped, and when the hot water storage amount in the hot water storage tank 3 becomes further smaller and becomes less than or equal to the set lower limit amount, the hot water storage amount in the hot water storage tank 3 Is supplied to the hot water storage tank 3 through the tank water supply passage 4 so as to be maintained at the set lower limit amount. Therefore, even if the amount of hot and cold water stored in the hot water storage tank 3 becomes smaller than the set reference amount, the water supply to the hot water storage tank 3 is still stopped, so that the temperature drop of the hot and cold water in the hot water storage tank 3 is suppressed, High-temperature hot and cold water whose decrease is suppressed will circulate across multiple dwelling units H,
It is possible to reduce the amount of additional heating in each dwelling unit H.
Further, when the amount of hot and cold water stored in the hot water storage tank 3 becomes further smaller than the set lower limit amount, water is supplied so that the amount of hot and cold water storage of the hot water storage tank 3 is maintained at the set lower limit amount. The supply of hot water to the dwelling unit H will not be interrupted.

In the exhaust heat recovery stop operation state, the cooling water circulation pump 8 is operated, the exhaust heat recovery circulation pump 13 is stopped to stop the hot water circulation operation of the exhaust heat recovery circulation means Ce, and the hot water supply circulation path. The on-off valve V2 is opened and the hot water supply circulation pump 15 is operated to operate the hot water supply circulation means Cs. As shown in FIG. 7, in the exhaust heat recovery stop operation state, the engine cooling water circulates through the exhaust heat recovery heat exchanger 2, but the exhaust heat recovery circulation pump 13 is stopped. The circulation of hot water in the hot water storage tank 3 through the heat recovery circulation path 11 through the heat recovery circulation path 11 is stopped, and the hot water in the hot water storage tank 3 circulates through a plurality of dwelling units H in the hot water supply circulation path 14. To do. Therefore, the hot and cold water of the hot water storage tank 3 circulates through the plurality of dwelling units H in the hot water supply circulation route 14, and in each dwelling unit H, hot water is circulated through the hot water supply circulation route 14 by the water heater K. become.

When the water level in the hot water storage tank 3 detected by the water level sensor 9 falls below the set reference water level as the amount of hot and cold water in the hot water storage tank 3 decreases, the tank water supply channel opening / closing valve V1
Is opened and water is supplied to the hot water storage tank 3 through the tank water supply passage 4, so that the temperature of the hot water in the hot water storage tank 3 is lowered.
Then, based on the fact that the temperature of the hot water in the hot water storage tank 3 detected by the hot water storage temperature sensor 10 becomes lower than the set upper limit temperature, the controller 5 switches to the operating state before switching to the exhaust heat recovery stop operating state.

In the circulation stop operation state, the cooling water circulation pump 8 is stopped, the tank water supply passage opening / closing valve V1 is closed to stop the water supply operation of the tank water supply means Wb, and the exhaust heat recovery circulation pump 13 is operated. Stop the hot water circulation operation of the exhaust heat recovery circulation means Ce, close the hot water supply circulation path opening / closing valve V2 and stop the hot water supply circulation pump 15 to stop the hot water circulation operation of the hot water supply circulation means Cs. Stop.

As shown in FIG. 8, in the circulation stop operation state, since the operation of the generator 1 is stopped and no exhaust heat is generated from the generator 1, the hot water storage through the exhaust heat recovery heat exchanger 2 is performed. The circulation of the hot water of the hot water tank 3 is stopped, and in that state, the circulation of the hot water of the hot water storage tank 3 through the hot water supply circulation path 14 is also stopped. Since there is no heat dissipation due to the circulation through the hot water, it is possible to suppress the temperature drop of the hot water in the hot water storage tank 3. When the circulation stop operation state is executed in this way, in each dwelling unit H, the hot water supply device K uses the water supplied through the dwelling unit water supply passage 16 to supply hot water.

In the circulation operation state, the cooling water circulation pump 8 is stopped, the tank water supply passage opening / closing valve V1 is closed to stop the water supply operation of the tank water supply means Wb, and the exhaust heat recovery circulation pump 13 is stopped. Then, the hot water circulation operation of the exhaust heat recovery circulation means Ce is stopped, the hot water supply circulation path opening / closing valve V2 is opened, and the hot water supply circulation pump 15 is operated to operate the hot water supply circulation means Cs. In addition, based on the detection information of the water level sensor 9, when the hot and cold water storage water level of the hot water storage tank 3 becomes equal to or lower than the set lower limit water level, the tank water supply channel opening / closing valve is provided so that the hot and cold water storage level is maintained at the set lower limit water level. V1 is controlled to be opened and closed to interrupt the water supply operation of the tank water supply means Wb.

As shown in FIG. 9, in the circulating operation state, since the operation of the generator 1 is stopped and no exhaust heat is generated from the generator 1, the hot water storage tank through the exhaust heat recovery heat exchanger 2 The circulation of hot and cold water of No. 3 is stopped, and in that state, the hot and cold water of the hot water storage tank 3 circulates through a plurality of dwelling units H in the hot water supply circulation path 14, and the hot and cold water storage amount of the hot water storage tank 3 is set to the set value. Water is supplied to the hot water storage tank 3 through the tank water supply passage 4 so as to be maintained at a limited amount. Therefore, in each dwelling unit H, the hot water supply device K can be used to supply hot water using the hot water circulating in the hot water supply circulation path 14.

That is, the operation control means U includes the controller 5, the exhaust heat recovery circulation pump 13, the hot water supply circulation passage opening / closing valve V2, the hot water supply circulation pump 15 and the tank water supply passage opening / closing valve V1.
It is configured with.

As shown in FIG. 1, in the first embodiment, the heat load detecting means L for detecting the heat quantity of the hot water supplied to the plurality of dwelling units H through the hot water circulating means Cs as a heat load, and the heat load thereof. The storage unit 5m of the controller 5 is provided as a storage unit that stores the heat load detected by the detection unit L, and the determination unit D predicts the heat load on the operation target day based on the storage information of the storage unit 5m. Based on the prediction information of the heat load prediction means P, the operation control means U configures the operation status into the normal operation status, the temperature reduction suppression operation status, the circulation operation status, and the circulation stop operation status. It is configured to switch automatically.

The heat load detecting means L will be further described.
When a command for test operation is issued from the operation unit 22, the controller 5 is in a normal operation state during power generation and in a circulation operation state during power generation stop during a preset test operation period (for example, one week). Run Test run. Then, during the test operation, the controller 5 detects the heat quantity as a heat load by calculating the heat quantity by multiplying the total hot water flow rate obtained by summing the detected hot water flow meters M3 by the temperature detected by the hot water temperature sensor 10. The heat load detection means L is configured to include each hot water flow meter M3, the hot water storage temperature sensor 10, and the controller 5. The storage unit 5m of the controller 5 is configured to store the heat load detected by the heat load detecting means L in association with time and day of the week. That is, in the storage unit 5m,
The temporal change of the heat load in which the heat load detected by the heat load detecting means L is associated with 24 hours a day is stored in association with the day of the week.

Then, the controller 5 predicts the heat load change over time corresponding to the day of the week of the operation target day as the heat load change over time of the operation target day based on the heat load change over time stored in the storage unit 5m. The heat load detected by the heat load detecting means L is stored in the storage unit 5m in association with the time and the day of the week, while the operation state is switched based on the predicted heat load as described later. In this way, as the temporal change of the heat load on the operation target day, the temporal change of the heat load corresponding to the day of the week of the operation target day of the previous week stored in the storage unit 5m is predicted. Therefore, the heat load predicting means P is configured by using the controller 5. That is, in the supply target dwelling unit group, the heat load temporal change during 24 hours a day becomes similar even if the days are different within the same month or the same season, if the day of the week is the same. By selecting the one corresponding to the day of the week of the operation target day from the thermal load time changes stored in the storage unit 5m, the heat load temporal change of the operation target day can be predicted.

It is to be noted that, over the course of one year, the change over time in heat load is stored in the storage unit 5m in association with the month, day and day of the week, and the average heat of each day of the week is stored for each month based on the data for one year. The load aging change is obtained and stored in the storage unit 5m as prediction data, and thereafter, based on the prediction data stored in the storage unit 5m, the heat load aging corresponding to the month and the day of the week of the operation target day. The change may be configured to predict a change over time in heat load of the operation target day.

Further, in the storage section 5m of the controller 5,
The first set heat load for power generation, the second set heat load for power generation, and the set heat load for power generation stop are preset and stored. By the way, set heat load for power generation stop <second for power generation
Set heat load <first set heat load for power generation. And
The controller 5 uses the predicted heat load based on the predicted change over time to generate the first predicted heat load during the execution of the normal operation state.
When the heat load exceeds the set heat load, it is determined that the circulating hot water use state has decreased to the hot water storage temperature state, and when the predicted heat load falls below the second set heat load for power generation while the temperature reduction suppression operation state is running, the circulating hot water use state changes to the hot water storage state. If it is determined that the temperature has risen and the predicted heat load becomes smaller than the set heat load for power generation stop at the time of power generation stop, it is determined that the circulating hot water usage state has become the low hot water supply load state at power generation stop, and the predicted heat load When the heat load exceeds the set heat load for power generation stop, it is determined that the circulating hot water usage state is the high hot water supply load state during power generation stop.
That is, the discriminating means D is also constructed by using the controller 5.

The control operation of the controller 5 in the first embodiment will be described with reference to FIG. FIG. 2 shows the predicted heat load change over time of the operation target day by the change over time of the predicted heat load rate. The predicted heat load rate is shown as a percentage with the sum of the predicted heat load of the operation target day being 100%. There is. The controller 5 operates the generator 1 in a predetermined generator operation time zone for one day (8 hours from 18:00 to 2:00, which is determined as a time zone in which a large amount of power is demanded in FIG. 2). . Then, when the predicted heat load is smaller than the first set heat load for power generation accompanying the start of operation of the generator 1, the operation is started in the normal operation state, and the predicted heat load is the first set heat load for power generation. In the above cases, start the operation in the temperature reduction suppression operation state,
After that, during power generation, when the predicted heat load becomes equal to or higher than the first set heat load for power generation during operation in the normal operation state, it is determined that the circulating hot water use state has decreased to the hot water storage temperature state, and the normal operation state is changed. When the predicted heat load becomes equal to or lower than the second set heat load for power generation during the operation in the temperature reduction suppression operation state, it is determined that the circulating hot water use state has become the hot water storage temperature increase state, and the temperature reduction is suppressed. Switch from the operating state to the normal operating state. When the predicted heat load becomes smaller than the set heat load for power generation stop during power generation stop, it is determined that the circulating hot water usage state has become the low hot water supply load state during power generation stop, and operation is performed in the circulation stop operation state. When the predicted heat load is equal to or higher than the set heat load for power generation stop, it is determined that the circulating hot water usage state has become the high hot water supply load state at power generation stop, and operation is performed in the circulation operation state.

That is, during power generation, when operating in the normal operating state, the predicted heat load may exceed the first set heat load for power generation, and the temperature of the hot water in the hot water storage tank 3 may drop. When it becomes a certain state, it is switched to the temperature reduction suppression operation state to prevent the temperature of the hot water in the hot water storage tank 3 from decreasing, and the predicted heat load is set to the second set heat for power generation during operation in the temperature reduction suppression operation state. When the load becomes less than or equal to the load and the temperature of the hot water in the hot water storage tank 3 may rise, the operating mode is switched to the normal operation state, and the rise in the temperature of the hot water in the hot water storage tank 3 is prevented. Further, when the predicted heat load is smaller than the set heat load at the time of power generation stop at the time of power generation stop, and it is predicted that the circulating hot water usage amount is small, the system is operated in the circulation stop operation state and is supplied through the hot water supply circulation path 14. Since the circulation of the hot water in the hot water storage tank 3 is stopped, the heat radiation through the hot water supply circulation path 14 is suppressed, the temperature drop of the hot water of the hot water storage temperature 3 is suppressed, and the predicted heat load is lower than the set heat load when power generation is stopped. When it is predicted that the amount of circulating hot water used is large, the hot water in the hot water storage tank 3 is circulated through the hot water supply circulation path 14 by operating in a circulating operation state. Circulation route 1
It is possible to supply hot water by using hot water that circulates through the hot spring 4.

Next, the water heater K provided in each dwelling unit H will be described with reference to FIG. The water heater K is a mixing section Km for mixing hot water supplied from the hot water supply passage 17 for a dwelling unit and water supplied from the water supply passage 16 for a dwelling unit, and the mixing section Km.
a heating unit Kh to which hot water is supplied as a heating target from m;
The remote controller operating unit 31 is provided with a hot water supply temperature setting unit for setting a target hot water supply temperature.

The heating section Kh is connected to the water supply channel 32 from the mixing section Km.
Heat exchanger 34 for heating the hot and cold water supplied through the hot water and the heated hot and cold water to the hot water supply passage 33, and the hot water for the bathtub (not shown) flowing through the reheating circulation passage 35. The heat exchanger 36 for heating, the gas burner 37 for heating the heat exchanger 34 for hot water supply and the heat exchanger 36 for additional heating, the heating control unit 38 for controlling the operation of the heating unit Kh, and the like are configured. .

The gas burner 37 has a gas supply passage 1 for a dwelling unit.
8 is connected to the dwelling unit gas supply path 18, and a gas interrupting valve 39 for interrupting the gas supply and a gas proportional valve 40 for adjusting the gas supply amount are provided.

The water supply passage 32 is provided with a water supply temperature sensor 41 for detecting the temperature of the supplied hot water and a water supply amount sensor 42 for detecting the flow rate of the supplied hot water, and the water supply passage 32 and the hot water supply passage 33 are connected by a water supply bypass. It is connected at the path 43. In the hot water supply passage 33, in order from the upstream side, a mixing valve 45 for adjusting the mixing ratio of hot water from the hot water supply heat exchanger 34 and water from the water supply bypass passage 43, and a water proportional valve 50 for adjusting the amount of hot water.
A hot water supply temperature sensor 44 for detecting the temperature of the hot water mixed by the mixing valve 45 is provided, and a hot water supply plug 49 is connected to the tip of the hot water supply passage 33. A hot water filling path 46 branched from the hot water supply path 33 is connected to a forward path of the reheating circulation path 35, and a hot water filling opening / closing valve 47 is provided in the hot water filling path 46. A bath circulation pump 48 that circulates bath water is provided in the return passage of the reheating circulation passage 35.

The mixing section Km is provided with a mixing valve 51 for adjusting a mixing ratio of hot water supplied from the hot water supply passage 17 for the dwelling unit (that is, hot water supply circulation means Cs) and water supplied from the dwell water supply passage 16. , Hot water supply passage opening / closing valve 52 for intermittently supplying hot water from the dwell unit hot water supply passage 17 to the mixing valve 51
And a circulating hot water temperature sensor 53 for detecting the temperature of hot water supplied from the hot water supply passage 17 for the dwelling unit to the mixing valve 51 (hereinafter sometimes referred to as circulating hot water temperature), and the mixing valve 51 from the hot water supply passage 16 for the dwelling unit. Supply temperature sensor 54 for detecting the temperature of the water supplied to (to be referred to as the mixing portion supply water temperature) and the temperature of the hot water flowing out from the mixing valve 51 (hereinafter sometimes referred to as the mixed hot water temperature) The mixing temperature sensor 55, the mixing control unit 56 for controlling the operation of the mixing unit Km, and the like are configured.

Next, the heating control section 38 and the mixing control section 56.
The control operation will be described. The heating control unit 38 is configured to communicate various control information with the remote control operation unit 31 and the mixing control unit 56, respectively, and the controller 5 communicates the circulation stop operation start information and the circulation stop operation end information. It is configured to. Remote control operation part 3
When the operation switch No. 1 is turned on, the heating control unit 38 and the mixing control unit 56 can be controlled, respectively, and the hot and cold water supply passage opening / closing valve 52 is opened to be in an operable state. Then, when the hot water tap 49 is opened and the hot water flow rate detected by the water supply amount sensor 42 reaches or exceeds the set amount, the heating control unit 38 causes the mixing control unit 5 to operate.
6, the target hot water supply temperature set by the remote control operation part 31 is transmitted, and the mixing control part 56 is sent from the circulating hot water temperature detected by the circulating hot water temperature sensor 53 and the heating control part 38. When the circulating hot water temperature is equal to or higher than the target hot water supply temperature, the effect is transmitted to the target hot water supply temperature, and when the circulating hot water temperature is lower than the target hot water supply temperature, the fact is transmitted to the heating control unit 38.

Further, the mixing control section 56 has a preset mixing target temperature which is set and stored therein. By the way, two types of low mixing target temperature and high mixing target temperature are set as the mixing target temperature, and the low mixing target temperature is set by the remote controller operating unit 3.
The target hot water supply temperature set in 1 corresponds to a preset normal target hot water supply temperature range (for example, 35 to 48 ° C.), and is set to, for example, 30 ° C. The target hot water supply temperature set by the remote controller operation unit 31 is a preset high-temperature target hot water supply temperature (for example, 60 °).
It corresponds to the case of C), and is set to 45 ° C., for example.

When the target hot water supply temperature is transmitted from the heating control unit 38 based on the fact that the hot water supply plug 49 is opened and the hot water flow rate detected by the water supply amount sensor 42 exceeds the set amount, the mixing control unit 56 When the circulating hot water temperature is equal to or higher than the target hot water supply temperature, the circulating hot water temperature sensor 5 compares the circulating hot water temperature detected by the circulating hot water temperature sensor 53 with the target hot water supply temperature.
3. Mixing control is performed to adjust the mixing valve 51 so that the mixed hot water temperature detected by the mixed temperature sensor 55 becomes the target hot water temperature based on the detected temperatures of the water supply temperature sensor 54 and the mixed temperature sensor 55, respectively. Then, the hot water from the dwelling unit hot water supply passage 19 and the water from the dwelling unit water supply passage 21 are mixed, and the fact that the circulating hot water temperature is equal to or higher than the target hot water supply temperature is transmitted to the heating control unit 38. The heating control unit 38 indicates that the circulating hot water temperature is equal to or higher than the target hot water supply temperature.
6, the gas burner 37 is put into the combustion stopped state. Therefore, the hot and cold water supplied from the mixing section Km to the heating section Kh is not heated by the heating section Kh and is discharged from the hot water tap 49, and the hot or cold water having the target hot water temperature or the substantially target hot water temperature is discharged from the hot water tap 49. Take a bath.

On the other hand, when the circulating hot water temperature is lower than the target hot water supply temperature, it is detected by the mixing temperature sensor 55 based on the detected temperatures of the circulating hot water temperature sensor 53, the supplied water temperature sensor 54 and the mixing temperature sensor 55. When the target hot water supply temperature is in the normal target hot water supply temperature range, the mixed hot water temperature becomes the low mixing target temperature, or when the target hot water supply temperature is the high temperature target hot water supply temperature, it becomes the high mixing target temperature.
Mixing control for adjusting the mixing valve 51 is executed so that the hot water from the hot water supply passage 19 for the dwelling unit and the water supply passage 2 for the dwelling unit
The fact that the circulating hot water temperature is lower than the target hot water supply temperature is transmitted to the heating control unit 38. When the heating control unit 38 receives a notification from the mixing control unit 56 that the circulating hot water temperature is lower than the target hot water supply temperature, the gas burner 37.
The target hot water supply temperature, the temperature detected by the water supply temperature sensor 41, and the water supply amount detected by the water supply amount sensor 42, so that the temperature of the hot water flowing out of the hot water supply heat exchanger 34 becomes the target hot water supply temperature. Feedforward control for adjusting the opening of the proportional valve 40 and the opening of the mixing valve 45 is executed, and the opening of the gas proportional valve 40 is adjusted based on the deviation between the detected temperature of the hot water temperature sensor 44 and the target hot water temperature. Execute feedback control for fine adjustment. Therefore, the hot water tap 49
From here, hot and cold water of the target hot water supply temperature will come out.

However, the heating controller 38 is the controller 5
When the circulation stop operation start information is received from the device, the mixing control unit 56 transmits a message to that effect, and when the mixing control unit 56 receives the circulation stop operation start information, the mixing control unit 56 closes the hot and cold water supply passage opening / closing valve 52 and also performs the above-described operation. Without executing each mixing control,
The mixing valve 51 is controlled so that the hot water supply passage 17 for the dwelling unit is closed and the water supply passage 16 for the dwelling unit is fully opened. Further, when the circulation stop operation end information is communicated from the controller 5, the heating control unit 38 communicates that fact to the mixing control unit 56, and when the mixing control unit 56 receives the circulation stop operation end information, the hot water The supply passage opening / closing valve 52 is opened, and each mixing control is executed as described above.

When the temperature of the hot water from the hot water supply circulation means Cs is lower than the target hot water supply temperature, the mixed target temperature is set so that the temperature can be adjusted to the target hot water supply temperature in a stable manner.
Since the hot water from the hot water supply circulation means Cs and the water from the dwelling unit water supply means Ws are mixed and then heated to the target hot water supply temperature in the heating section Kh, the hot water from the hot water supply circulation means Cs is mixed. Even if the difference between the temperature and the target hot water supply temperature is small, hot or cold water having the target hot water supply temperature or substantially the target hot water supply temperature can be obtained. That is, in order to secure the combustion stability of the gas burner 37, the combustion amount of the gas burner 37 is set to be smaller than a predetermined minimum combustion amount so as not to be throttled. Therefore, when the hot water mixing control as described above, that is, the control of mixing the hot water from the hot water circulating means Cs and the water from the dwelling unit water supplying means Ws so as to reach the mixing target temperature is not performed, the hot water circulating means When the difference between the hot water temperature from Cs and the target hot water supply temperature is small and the combustion amount obtained based on the difference is smaller than the minimum combustion amount, for example, the gas burner 37 is burned at the minimum combustion amount. Therefore, it is difficult to adjust the temperature of hot water to be discharged to the target hot water supply temperature. Therefore, by performing the hot and cold water mixing control as described above, the problems as described above can be solved.

In other words, the water heater K has a circulating means Cs for hot water supply.
Mixing of hot water supplied through the housing unit and water supplied through the dwelling unit water supply unit Ws, or a heating unit Kh as a heating unit.
The hot water is heated at the target hot water temperature.

[Second Embodiment] Hereinafter, based on the drawings,
A second embodiment of the present invention will be described. The second embodiment has the same configuration as that of the first embodiment described above except that the configurations of the determining unit D and the operation control unit U are different.
Mainly, the determination means D and the operation control means U different from those of the first embodiment will be described, and the same components as those of the first embodiment or components having the same action will be denoted by the same reference numerals to avoid redundant description. Therefore, the description will be omitted.

Similar to the first embodiment, the discriminating means D is configured to discriminate between the hot water storage temperature lowered state, the hot water storage temperature raised state, the high hot water supply load state during power generation stop, and the low hot water supply load state during power generation stop. As in the first embodiment, the controller 5 is configured to switch the operating state between the normal operating state, the temperature reduction suppressing operating state, the exhaust heat recovery stop operating state, the circulation stop operating state, and the circulating operating state, The control operation in each operating state is the same as the control operation in the first embodiment described with reference to FIGS. 6 to 9, and therefore description thereof will be omitted. Further, as in the first embodiment, the controller 5 communicates the circulation stop operation start information to the water heater K of each dwelling unit H as the operation in the circulation stop operation state is started.
Circulation stop operation end information is communicated with the stop of the operation in the circulation stop operation state. The configuration and control operation of the water heater K are also the same as those in the first embodiment, so description thereof will be omitted.

As shown in FIG. 3, in the second embodiment, the discriminating means D is a hot water storage temperature detecting means for detecting the temperature of hot and cold water in the hot water storage tank 3 for determining the circulating hot and cold water usage state during power generation. The temperature sensor 10 is provided, and the circulating hot and cold water usage state determination at the time of power generation stop is provided with a clocking means T for measuring the time. The operation control means U detects the information detected by the hot water storage temperature sensor 10 at the time of power generation. The operating state is switched between the normal operating state and the temperature drop suppressing operating state based on the above, and when the power generation is stopped, the operating state is switched between the circulating operating state and the circulating stop operating state based on the measurement information of the time measuring means T. I am doing it.

In the storage section 5m of the controller 5, the upper set temperature, the lower set temperature (however, the lower set temperature <the upper set temperature), and the low hot water supply load time zone at the time of power generation stop are preset and stored. . The lower set temperature is a temperature at which it is necessary to prevent the temperature from falling too low when the amount of circulating hot water used increases and the temperature of the hot water in the hot water storage tank 3 decreases during operation in the normal operation state. For example, the temperature is set to about 50 ° C., and the upper set temperature is
When the amount of circulating hot water used decreases and the temperature of the hot water in the hot water storage tank 3 rises, the temperature is set to a state where it is necessary to prevent the hot water from rising too high, for example, about 55 to 60 ° C. In addition, the low hot water supply load time period when power generation is stopped is the time period when the amount of circulating hot water used is expected to be small when power generation is stopped,
For example, it is set between 2 am and 6 am.

Then, the controller 5 is
Based on the detected temperature of the hot water storage temperature sensor 10, when the detected temperature becomes lower than the lower preset temperature during execution of the normal operation state, it is determined that the circulating hot water use state has decreased to the hot water storage temperature lowering state, When the detected temperature is equal to or higher than the upper set temperature, it is determined that the circulating hot water usage state has increased to the hot water storage temperature state, and when the power generation is stopped, the circulating hot water is supplied while the time measured by the time measuring means T is the low hot water supply load time period when the power generation is stopped. It is determined that the usage state is the low hot water supply load state when the power generation is stopped, and the circulating hot water use state is the high hot water supply load state when the power generation is stopped while the time measured by the timing means T is other than the low hot water supply load time period when the power generation is stopped. It is configured to determine that. That is, the discriminating means D is also constructed by using the controller 5. In addition, the timing means T also
It is configured using the controller 5.

The control operation of the controller 5 in the second embodiment will be described with reference to FIG. In FIG. 4, the bar graph shows the predicted heat load change over time in the housing complex where the cogeneration system is installed, and the bar graph of the predicted heat load change over time indicates the predicted heat load. 1 with the total sum as 100%
The predicted heat load rate for each hour is shown as a percentage. In addition, a solid line graph shows the change over time in the temperature of the hot and cold water in the hot water storage tank 3 when the operating states are switched between the normal operating state, the temperature drop suppressing operating state, the circulation stop operating state and the circulating operating state. A broken line graph shows a change over time in the temperature of the hot water in the hot water storage tank 3 when always operating in a normal operating state during power generation and always operating in a circulating operating state during power generation stop.

The controller 5 operates in a predetermined generator operating time zone for one day (in FIG. 4, 8 hours from 18:00 to 2:00, which is set as a time zone in which power demand is high). To drive. When the detected temperature of the hot water storage temperature sensor 10 is higher than the lower set temperature with the start of operation of the generator 1, the operation is started in the normal operation state, and the detected temperature of the hot water storage temperature sensor 10 is equal to or lower than the lower set temperature. At this time, the operation is started in the temperature reduction suppression operation state, and thereafter, during the power generation, when the temperature detected by the hot water storage temperature sensor 10 becomes lower than or equal to the lower set temperature during the operation in the normal operation state, the circulating hot water use state decreases the hot water storage temperature. When it is determined that the state has changed, the normal operation state is switched to the temperature reduction suppression operation state, and when the temperature detected by the hot water storage temperature sensor 10 becomes equal to or higher than the upper preset temperature during the operation in the temperature reduction suppression operation state, the circulating hot water usage state indicates the hot water storage temperature When it is determined that the temperature has risen, the temperature reduction suppression operation state is switched to the normal operation state. Further, during the power generation stop, based on the measurement information of the time measuring means T, during the power generation stop low hot water supply load time zone, it is determined that the circulating hot water use state is the power generation stop low hot water supply load state, and the circulation stop operation is performed. The state is executed, and in the time period other than the low hot water supply load time period when the power generation is stopped, it is determined that the circulating hot water use state is the high hot water supply load state when the power generation is stopped, and the circulation operation state is executed.

That is, as shown by the solid line graph in FIG. 4, the hot water storage temperature sensor 10 is operated during power generation.
When the detected temperature of is less than or equal to the lower set temperature, the temperature of the hot water in the hot water storage tank 3 may be too low.
The temperature of the hot water storage tank 3 is prevented from lowering by being operated in the temperature lowering suppression operation state, and the predicted heat load becomes equal to or higher than the upper preset temperature during the operation in the temperature reduction suppression operation state.
When there is a possibility that the temperature of the hot and cold water of the hot water will rise excessively, the hot water temperature of the hot water storage tank 3 is prevented from rising by switching to the normal operation state. Also, when power generation is stopped, when it is predicted that the amount of circulating hot water used is low during the time period when power generation is low and the hot water supply load time is low, it is operated in the circulation stop operating state,
Since the circulation of the hot water in the hot water storage tank 3 through the hot water supply circulation path 14 is stopped, the heat radiation through the hot water supply circulation path 14 is suppressed, and the decrease in the temperature of the hot water of the hot water storage temperature 3 is suppressed,
When it is predicted that the amount of circulating hot water used is large during the time period other than the low hot water supply load time period when power generation is stopped, the hot water in the hot water storage tank 3 is circulated through the hot water supply circulation path 14 by operating in the circulation operation state. Therefore, in each dwelling unit H, it is possible to supply hot water by using hot water that circulates in the hot water supply circulation path 14.

As shown by the broken line graph in FIG. 4, when the generator is always operated in the circulating operation state when the power generation is stopped, the amount of heat radiated through the hot water supply circulation path 14 is large, so that the hot water in the hot water storage tank 3 is lowered. It can be seen that, when operating in a normal operating state at all times during power generation, when the amount of circulating hot water used increases, the hot water in the hot water storage tank 3 drops significantly.

[Another Embodiment] Another embodiment will be described below. (A) The specific configuration of the determining means D is not limited to the configuration illustrated in the above embodiment. For example,
The circulating hot water usage state may be determined based on the rate of change in the temperature of the hot water in the hot water storage tank. In addition, the above first
In the embodiment, as the heat load detection means L, the case where the heat quantity of the hot water supplied to the plurality of dwelling units H through the hot water supply circulation means Cs is detected as the heat load has been exemplified. As a circulation means C for hot water supply
The storage means 5 is configured to detect the supply amount of hot water supplied to a plurality of dwelling units H through s as a heat load.
m is configured to store the heat load detected by the heat load detection means L, and the determination means D is a prediction means P that predicts the heat load on the operation target day based on the storage information of the storage means 5m. May be provided. In this case, the supply amount of hot water supplied to the plurality of dwelling units H through the hot water supply circulation means Cs is obtained based on the detection information of the hot water flow meter M3. Alternatively, a centralized flow meter is provided in a portion of the hot water supply circulation path 14 that corresponds to the upstream side of the connection point of the hot water supply passage 17 for the dwelling unit, and the hot water supplied to the plurality of dwelling units H is supplied by the centralized flow meter. The amount may be detected.

Further, the heat load detecting means L is configured to detect the hot water supply amount or heat quantity of hot water supplied by the water heater K in the supply target dwelling unit group as a heat load, and the storage means 5m stores the heat. The heat load detected by the load detection unit L is configured to be stored, and the determination unit D is configured to include a prediction unit P that predicts the heat load on the operation target day based on the storage information of the storage unit 5m. May be. In this case, a mixing section flow meter for detecting the flow rate of water supplied to the mixing section Km of the water heater K is provided in the dwelling unit water supply channel 16, and the target hot water supply temperature in each dwelling unit H is assumed to be 40 ° C, for example. Then, based on the assumed target hot water supply temperature and the detection information of each of the hot water flow meter M3 and the mixing section flow meter, the heat quantity of the hot water supplied by the water heater K in the supply target dwell unit group is obtained. Alternatively, the hot water supply amount of hot water supplied by the water heater K in the supply target dwell unit group is obtained based on the detection information of each of the hot water flow meter M3 and the mixing unit flow meter.

(B) In the first embodiment described above, the temporal change in heat load is configured to be stored in association with the weather conditions such as temperature and weather, and the weather conditions such as temperature and weather are taken into consideration. Then, it is preferable to configure so as to predict the temporal change of the heat load on the operation target day, because the temporal change of the heat load on the operation target day can be more accurately predicted.

(C) In the above-described embodiment, the operation control means U is configured to include the controller 5, and the controller 5 causes the controller 5 to perform the normal operation state, the temperature reduction suppressing operation state, the circulation operation state, and the circulation stop operation state. Although the case where the operating states are automatically switched is described above, the controller 5 may be omitted and the operating states may be switched manually.

(D) In the above embodiment, the case where the operating state is switched between the normal operating state and the temperature drop suppressing operating state during power generation has been exemplified.
By omitting such a switching configuration, during power generation,
It may be configured to operate in a normal operation state.

(E) The specific structure of the hot water storage tank 3 is not limited to the open type of one tank as exemplified in the above embodiment, and for example, the closed type of one tank (the structure shown in FIG. 11) or Alternatively, a two tank open type having a low temperature tank and a high temperature tank may be used. The open type of the two tanks includes a low temperature tank to which water is supplied by the tank water supply means Wb, and a high temperature tank to which hot water is supplied in an overflow state from the low temperature tank, and the exhaust heat recovery circulation means Ce is The hot water is taken out of the low temperature tank and is returned to the low temperature tank. The hot water recovery circulation circuit circulates the hot water, and the hot water supply circulation means Cs takes hot water from the high temperature tank and returns it to the low temperature tank. The hot water supply circulation path 14 to be returned is configured to circulate hot water. In this case, hot water is supplied to the high-temperature tank from the high-temperature layer above the low-temperature tank in an overflow state, and the storage temperature of the hot-water in the high-temperature tank is stabilized. Stabilize.

(F) In the above embodiment, the water heater K is illustrated as having both the mixing section Km and the heating section Kh, but the mixing section Km may be omitted.

(G) When the power generation means is constituted by the engine-driven rotary generator 1 driven by an engine such as a gas engine as in the above embodiment, a heat exchanger for exhaust heat recovery is used. The exhaust heat of the generator 1 to be supplied to 2 is configured to supply not only the engine cooling water exemplified in the above embodiment, but also the engine exhaust gas or both the engine cooling water and the exhaust gas. May be. When the power generation means is composed of the engine-driven rotary power generator 1, the engine is not limited to the one that uses the city gas as a fuel in the above-described embodiment, but various types of LP gas, petroleum, gasoline, and the like. It is possible to use the fuel of the above. In addition to the engine-driven rotary generator 1 exemplified in the above embodiment, the power generation means may be a gas turbine-driven rotary generator driven by a gas turbine. good. When the power generation means is composed of a gas turbine driven rotary generator, the exhaust heat recovery heat exchanger 2 is configured to supply the exhaust gas of the gas turbine as exhaust heat. Further, the power generation means is not limited to the rotary type generator as described above, but may be composed of various fuel cells, for example. When the power generation means is composed of a fuel cell, the heat exchanger 2 for recovering exhaust heat is supplied with cooling water of the fuel cell as exhaust heat.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a cogeneration system according to a first embodiment.

FIG. 2 is a diagram for explaining switching of a normal state in the cogeneration system according to the first embodiment.

FIG. 3 is a block diagram showing an overall configuration of a cogeneration system according to a second embodiment.

FIG. 4 is a diagram illustrating switching of a normal state in the cogeneration system according to the second embodiment.

FIG. 5 is a block diagram showing a hot water flow state in a normal operation state in the cogeneration system according to the embodiment.

FIG. 6 is a block diagram showing a hot and cold water flowing state in a temperature reduction suppressing operation state in the cogeneration system according to the embodiment.

FIG. 7 is a block diagram showing a hot water flow state in an exhaust heat recovery stop operation state in the cogeneration system according to the embodiment.

FIG. 8 is a block diagram showing a hot water flow state in a circulation stop operation state in the cogeneration system according to the embodiment.

FIG. 9 is a block diagram showing a hot water flow state in a circulation operation state in the cogeneration system according to the embodiment.

FIG. 10 is a block diagram showing a configuration of a water heater of the cogeneration system according to the embodiment.

FIG. 11 is a block diagram of a conventional cogeneration system.

[Explanation of symbols]

1 power generation means 2 Exhaust heat recovery heat exchanger 3 hot water storage tank 5m storage means 14 Circulation route for hot water supply Ce Exhaust heat recovery circulation means Cs hot water circulation means D discrimination means H dwelling unit K water heater Kh heating means L heat load detection means P heat load prediction means U operation control means Water supply means for Wb tank Water supply for Ws dwelling units

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI theme code (reference) H02P 9/04 F24D 17/00 P (72) Inventor Kawa ▲ ▼ ▼ Saiji Hirano, Chuo-ku, Osaka-shi, Osaka 4-1-2 Machi Osaka Gas Co., Ltd. F term (reference) 3L073 AA02 AA08 AA12 AA18 AB07 AB09 AB12 AC01 AC06 AD03 AE01 AE06 5H590 AA02 CA09 CA21 CA26

Claims (5)

[Claims] 1. A power generation unit for generating power in a region or an apartment house as an electric power supply target, a heat exchanger for recovering exhaust heat supplied with exhaust heat from the power generation unit, and a plurality of dwelling units included in the region or apartment house. A hot water storage tank that stores hot water for hot water supply,
Tank water supply means for supplying water to the hot water storage tank, exhaust heat recovery circulation means for circulating hot water between the exhaust heat recovery heat exchanger and the hot water storage tank, hot water supply circulation path between the hot water storage tank and the plurality of dwelling units A hot water supply circulation means for circulating hot water, a dwelling unit water supply means for supplying water to each of the plurality of dwelling units, and an operation control means for controlling operation are provided, and the hot water supply circulation is provided for each of the plurality of dwelling units. A hot water supply unit for supplying hot water to a hot water demand section using hot water supplied through the means and water supplied through the dwelling unit water supply means, wherein the operation control means operates the power generation means. When the power generation is stopped, the water supply operation of the tank water supply means and the hot water circulation operation of the exhaust heat recovery circulation means are stopped, and the hot water supply circulation means is turned into hot water. There are two operating states: a circulating operation state in which the ring operation is performed, a water supply operation in the tank water supply means, a hot water circulation operation in the exhaust heat recovery circulation means, and a circulation stop operation state in which the hot water circulation operation in the hot water supply circulation means is stopped. A cogeneration system that can be switched. 2. A discriminating means for discriminating the use state of the hot water circulating in the hot water circulating means in the plurality of dwelling units is provided, and the operation control means, based on the discrimination information of the discriminating means, The cogeneration system according to claim 1, wherein the cogeneration system is configured to automatically switch the operating state between the circulating operating state and the circulating stop operating state. 3. The operation control means keeps the hot and cold water storage amount at the set lower limit amount when the hot and cold water storage amount in the hot water storage tank becomes equal to or lower than a set lower limit amount in the circulation operation state. The cogeneration system according to claim 1 or 2, wherein the cogeneration system is configured to control the water supply operation of the tank water supply means. 4. The hot water supply device supplies hot water at a target hot water supply temperature by mixing hot water supplied through the hot water supply circulation unit with water supplied through the dwelling unit water supply unit or by heating by a heating unit. Claim 1 which is configured
The cogeneration system according to any one of 3 above. 5. A heat load detecting means for detecting, as a heat load, a supply amount or a heat amount of hot water supplied to the plurality of dwelling units through the hot water supply circulating means when the power generation is stopped, and the heat load detecting means detects the heat load. Storage means for storing the heat load is provided, the determining means, based on the storage information of the storage means,
It is configured to include a heat load prediction unit that predicts a heat load when the power generation is stopped on an operation target day, and the operation control unit is based on prediction information of the heat load prediction unit, and the circulation operation state and the circulation stop. The operation state is configured to be switched to the operation state.
The cogeneration system according to claim 1.