JP2015155780A - Cogeneration device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cogeneration device capable of suppressing power consumption while securing an operation of a hot water heating device, and using electric power by another electric power load, in a case when the cogeneration device is driven by receiving supply of electric power generated by an autonomous operation from a power generating portion in power failure of a commercial power system.

SOLUTION: A ratio of ON time tp and OFF time tc in supplying a low-temperature water (60°C) per one cycle, is changed to regulate a heating temperature control level of a low-temperature heating terminal between a maximum level and a minimum level. In an autonomous operation, change is implemented to supply high-temperature water (80°C) to the low-temperature heating terminal, so that a ratio of the OFF time tc can be increased in realizing the same heating temperature control level. A pump operation time is reduced by increasing the OFF time, so that consumption of driving power can be suppressed, and the power can be used in driving an antifreezing heater and the like at that rate.

COPYRIGHT: (C)2015,JPO&INPIT

Description

  The present invention relates to a cogeneration apparatus including a power generation unit, a hot water storage tank that recovers and stores exhaust heat generated in the power generation unit, and a hot water heating apparatus that uses the hot water storage. The present invention relates to a technology capable of reducing power consumption while ensuring the original driving operation when switched.

  In patent document 1, as control at the time of self-sustained operation, the power load at the time of self-sustained operation is divided into a plurality, and when it is detected that the power load is in an overload state, until the overload state is resolved In addition, it is disclosed that the power supply is cut off step by step for each current load section except for the coolant pump.

JP 2008-223559 A

  By the way, the cogeneration apparatus which heat-stores in a hot water storage tank by collection | recovery of the waste heat which arises in a power generation part, and utilizes the stored hot water as a heat source of a hot water heating apparatus is known. Such a cogeneration apparatus is normally driven mainly in a grid-connected operation mode in which power is supplied from a commercial power system, but is driven in a self-sustaining operation mode in which power is generated from a power generation unit when a power failure occurs in the commercial power system. Configured to be. Here, the hot water heater is circulated and supplied with a high temperature heating terminal such as a bathroom dryer that circulates and supplies high temperature water (for example, 80 ° C. high temperature water) as a heat source and a low temperature water (for example, 60 ° C. low temperature water) as a heat source. There are two types of low-temperature heating terminals such as floor heating devices. However, due to functional differences between the two, high-temperature heating terminals often end in a relatively short time, but low-temperature heating terminals are operated continuously, such as continuous operation. There are many. For this reason, electric power consumption is continuously accompanied especially for the heating operation of the low-temperature heating terminal.

  However, when a power failure occurs in the commercial power system and the operation mode is switched to the self-sustained operation mode, the generated power supplied from the power generation unit is limited, and operation of some power loads cannot be performed due to insufficient power supply. There is a risk of falling into a situation. In particular, even among hot water heaters, the floor heater may be operated continuously by the user, for example, throughout the day, and as a result of the continuous power consumption, the power supply to other important power loads is continued. There will be a situation where operation becomes impossible due to shortage. For example, although the purpose is achieved by intermittent operation such as freezing prevention operation for piping through which cold water such as water supply is passed among the piping constituting the cogeneration device, the operation operation important for the cogeneration device becomes impossible. It will lead to a situation.

  The present invention has been made in view of such circumstances, and an object of the present invention is when a power failure occurs in a commercial power system and the power generation unit is driven by receiving supply of generated power by a self-sustaining operation. Furthermore, it is providing the cogeneration apparatus which aims at suppression of electric power consumption, ensuring the driving | operation operation | movement of a hot water heating apparatus, and enables electric power use with another electric power load.

  In order to achieve the above object, the present invention utilizes a power generation unit, a hot water storage tank that collects exhaust heat generated during power generation operation in the power generation unit and stores it as hot water, and hot water in the hot water storage tank. A hot water heating device that performs a heating operation by supplying hot water, wherein the hot water heating device supplies low temperature water having a first temperature to dissipate heat, and a second temperature that is higher than the first temperature. A high-temperature heating terminal that supplies and dissipates heat by supplying high-temperature water, and a heating operation control unit that performs operation control related to the supply of hot water, and is normally supplied with power by grid-connected operation with a commercial power system. On the other hand, when a power failure occurs in the commercial power system, the following specific matters are intended for a cogeneration device configured to be driven by a self-sustaining operation that receives supply of generated power from the power generation unit. It was decided to prepare for. That is, when the heating operation control unit is driven by the grid interconnection operation, when only the low temperature heating terminal is operated, low temperature water having the first temperature is supplied to the low temperature heating terminal in principle. On the other hand, when driven by the self-sustained operation, a change control is performed so that the high-temperature water having the second temperature is supplied to the low-temperature heating terminal (Claim 1).

  In the case of the present invention, when driven by self-sustained operation, the above-described change control reduces power consumption and suppresses power consumption, enabling use of power at a power load other than the hot water heater. Will get. That is, even when driven by independent operation, if low temperature water is supplied to the low temperature heating terminal in the same manner as when driven by grid connection operation, supply of low temperature water is continued as long as heating operation continues. It may be necessary to carry out the operation continuously, and for this purpose, for example, the pump will be used to continue to use the power, and the use of power at the power load in the cogeneration device other than the hot water heating device will be limited. There is a risk that. On the other hand, when high-temperature water is supplied to the low-temperature heating terminal, the same heating effect can be obtained even if the supply amount is reduced or the supply time is shortened in obtaining the same heating effect in the low-temperature heating terminal. . For this reason, the use of electric power for pump operation can be suppressed or cut by reducing the supply amount or shortening the supply time, so that it can be used as drive power for operation operation of other power loads. Become. “In principle,” when “driven by grid interconnection operation, when only the low-temperature heating terminal is operated, the low-temperature water having the first temperature is supplied to the low-temperature heating terminal in principle”. Means that, in the initial stage of starting the operation of the low-temperature heating terminal, the low-temperature water having the first temperature is used to rapidly increase the temperature in consideration of the fact that the floor heating, which is the low-temperature heating terminal, is started from a cold state. Instead, hot water at a higher temperature is supplied to the low-temperature heating terminal, and in a steady state after the heating temperature reaches a predetermined temperature, the low-temperature water at the first temperature is supplied and the heating operation by the low-temperature heating terminal is continued. This is in consideration of the driving situation.

  The heating operation control unit of the cogeneration apparatus of the present invention can be configured to change and control the supply amount to the low-temperature heating terminal according to the heating temperature control level in the low-temperature heating terminal (Claim 2). Thus, the amount of driving power used can be reduced by changing the supply amount, that is, changing the pump operation amount.

  As one form of the change in the supply amount, the heating operation control unit is configured to control the ON / OFF of the hot water supply to the low-temperature heating terminal, and to change and control the ratio of the ON time / OFF time per cycle time. (Claim 3). In other words, by changing the supply time of hot water in one cycle time, it is possible to change the supply amount of hot water per cycle time and to completely cut off power consumption during the OFF time. Is possible.

  In the cogeneration apparatus of the present invention, in order to heat the heat source for heating the hot water supplied to the hot water heating apparatus, a combustion heating type auxiliary heat source machine can be provided (claim 4). In this way, it is possible to easily and reliably change the hot water supplied to the low temperature heating terminal from the low temperature water to the high temperature water.

  The cogeneration apparatus according to the present invention may include a freeze prevention operation control unit that receives the drive power supply and executes the freeze prevention operation control (claim 5). By reducing the power consumption in the hot water heater, it is possible to execute the freeze prevention operation control with the corresponding power.

  At that time, as the freeze prevention operation control unit, when driven by the self-sustained operation, when the power consumption of the generated power supplied from the power generation unit is equal to or greater than a predetermined value, the configuration is made to wait for the execution of the freeze prevention operation control (Claim 6). When the amount of power generated from the power generation unit becomes smaller than the predetermined value, freeze prevention operation control may be started, and power consumption from the power generation unit due to power usage by other power loads, etc. If the amount becomes temporarily larger than the predetermined value, it is possible to wait for the start of the freeze prevention operation until it is resolved. It becomes possible.

  As described above, according to the cogeneration apparatus of the present invention, when driven by self-sustaining operation, it is possible to reduce power consumption and suppress power consumption by change control in the heating operation control unit. It is possible to use electric power with an electric power load other than the hot water heater. That is, even when driven by independent operation, if low temperature water is supplied to the low temperature heating terminal in the same manner as when driven by grid connection operation, supply of low temperature water is continued as long as heating operation continues. It may be necessary to carry out the operation continuously, and for this purpose, for example, the pump will be used to continue to use the power, and the use of power at the power load in the cogeneration device other than the hot water heating device will be limited. There is a risk that. On the other hand, when high-temperature water is supplied to the low-temperature heating terminal, the same heating effect can be obtained even if the supply amount is reduced or the supply time is shortened in obtaining the same heating effect in the low-temperature heating terminal. For this reason, the use of electric power for operating the pump can be suppressed or cut by reducing the supply amount or shortening the supply time. As a result, it can be used as drive power for driving operation of another power load.

  According to the cogeneration apparatus of claim 2, the heating operation control unit is configured to change and control the supply amount to the low-temperature heating terminal according to the heating temperature control level in the low-temperature heating terminal, for example, change of the pump operation amount The amount of drive power used can be reduced.

  According to the cogeneration apparatus of claim 3, the heating operation control unit is configured to ON / OFF control the hot water supply to the low temperature heating terminal and to change and control the ratio of the ON time / OFF time per cycle time. This makes it possible to change the hot water supply time for one cycle time, change the hot water supply amount per cycle time, and completely cut off power consumption during the OFF time. Will be able to.

  According to the cogeneration apparatus of the fourth aspect, in order to heat the heat source for heating the hot water supplied to the hot water heating apparatus, a combustion heating type auxiliary heat source device is provided to supply to the low temperature heating terminal. The change from the low temperature water to the high temperature water can be easily and reliably performed.

  According to the cogeneration apparatus of claim 5, based on the reduction of power consumption in the hot water heating apparatus by including the freeze prevention operation control unit that receives the power supply for driving and executes the freeze prevention operation control. Thus, the freeze prevention operation control can be executed with the electric power.

  According to the cogeneration apparatus of claim 6, when the freezing prevention operation control unit is driven by the self-sustained operation, when the power consumption of the generated power supplied from the power generation unit exceeds a predetermined value, the freeze prevention operation control is performed. When the consumption of the generated power from the power generation unit becomes smaller than the predetermined value by setting the configuration to wait for execution, it is sufficient to start the freeze prevention operation control, which is caused by the use of power by another power load or the like. Thus, if the consumption of the generated power from the power generation unit temporarily becomes larger than a predetermined value, it is possible to wait for the start of the freeze prevention operation until it is eliminated. As a result, reliable control can be performed even during a self-sustaining operation where there is a risk of power shortage.

It is a mimetic diagram of a cogeneration device concerning an embodiment of the present invention. It is explanatory drawing which shows the ON-OFF condition in various conditions of the thermal valve for supplying warm water to the floor heating terminal in a warm water heater.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram of a cogeneration apparatus according to an embodiment of the present invention. In the figure, reference numeral 2 is a power generation unit, 3 is a hot water storage tank, 4 is a water supply circuit for supplying tap water from the outside to the hot water storage tank 3 etc., and 5 is hot water storage from the hot water storage tank 3 or an auxiliary heat source 6 A hot water supply circuit that supplies hot water to the hot-water tap 7 using hot water after heating, and 8 is an external heat load that circulates to the external heat load using hot water after auxiliary heating or hot water stored in the hot water storage tank 3 as a heat source by the auxiliary heat source unit 6 Reference numeral 9 denotes a hot water heating circuit as a hot water heating apparatus that circulates and supplies hot water heat-exchanged and heated by a heat source circulated and supplied from the external heat load circuit 8, and 10 circulates hot water in the bathtub 102 from the external heat load circuit 8 A reheating circuit that reheats and heats with a supplied heat source, 11 a waste heat recovery circuit that heats hot water in the hot water storage tank 3 by recovering exhaust heat from the power generation unit 2, and 12 a hot water from the bottom of the hot water storage tank 3. To the auxiliary heat source unit 6 Bottom outlet passage of the camera in order to 13 top outlet passage for guiding the hot water from the top of the hot water storage tank 3 to the auxiliary heat source unit 6, 14 is a controller controlling the operation of the cogeneration system.

  In the present embodiment, the power generation unit 2 will be described with reference to an example using a fuel cell (for example, SOFC; solid oxide fuel cell) 21, but the power generation unit 2 is not limited thereto. As long as it is possible to recover the exhaust heat by heating the hot water in the hot water storage tank 3 using the exhaust heat to be used as a heat source, for example, a gas engine capable of recovering the exhaust heat from the engine cooling water and generating electricity is used as the power generation unit. be able to. The fuel cell 21 generates power using a gas supplied from a gas supply system (not shown) as fuel, and the exhaust heat generated from the fuel cell 21 is supplied to the exhaust heat recovery heat exchanger 22 as a heat source. On the other hand, hot water from the bottom 31 of the hot water storage tank 3 supplied by the exhaust heat recovery circuit 11 is supplied to the exhaust heat recovery heat exchanger 22 as a heat exchange heating target.

  That is, the exhaust heat recovery circuit 11 includes an outlet 111 connected to the bottom 31 of the hot water storage tank 3 and an upstream end connected to the heated inlet of the heat exchanger 22 for exhaust heat recovery. The heat exchanger 22 is provided with an introduction path 112 connected to the heated outlet of the heat exchanger 22 and having a downstream end connected to the top of the hot water storage tank 3 and an exhaust heat recovery pump 113. Then, when the exhaust heat recovery operation control by the exhaust heat recovery operation control unit of the controller 14 is started, the circulation pump 113 is operated, whereby the hot water taken out from the bottom 31 of the hot water storage tank 3 through the outlet path 111 is In the heat exchanger 22 for exhaust heat recovery, heat exchange heating is performed by exhaust heat from the fuel cell 21, and the hot water after the heat exchange heating is returned to the top of the hot water storage tank 3 through the introduction path 112, and temperature stratification is performed in the hot water storage tank 3. The water is stored as hot water having a predetermined temperature (for example, 65 ° C. or higher).

  A three-way switching valve 114 is interposed in the middle of the introduction path 112, and a bypass path 115 branched from the middle position of the introduction path 112 to bypass the hot water storage tank 3 is connected to the three-way switching valve 114. ing. The three-way switching valve 114 is maintained in an exhaust heat recovery switching state in which the outlet 31 of the hot water storage tank 3 and the exhaust heat recovery heat exchanger 22 are communicated with each other during the exhaust heat recovery operation. 1 is a heat exchanger inlet temperature sensor for detecting the hot water temperature before heat exchange heating, and 117 is a heat exchanger outlet temperature sensor for detecting the hot water temperature after heat exchange heating. is there.

  The hot water storage tank 3 is configured in a hermetically sealed manner, and hot water storage temperature sensors 32, 33, 34, 35 for detecting the internal hot water storage temperature at the vertical positions are provided at predetermined positions in the vertical direction of the hot water storage tank 3, respectively. 36 is installed.

  In the water supply circuit 4, the upstream end of the main water supply channel 41 is connected to an external water supply or the like, and the downstream end is connected to the bottom 32 of the hot water storage tank 3 through a check valve, so that hot water in the hot water storage tank 3 is consumed from the top. If it is done, water can be supplied to the hot water storage tank 3 based on the water supply pressure for the consumed amount. Further, the downstream side of the main water supply channel 41 is connected so as to merge with the bottom outlet channel 12. Further, a mixed water supply channel 44 branched from the upstream side of the main water supply channel 41 is connected to a first mixing valve 54 (described later) of the hot water supply channel 5 so that water can be supplied. A branch water supply channel 45 branched from the upstream side of the main water supply channel 41 is connected to a heating / expansion tank 94 described later so as to be replenished. Reference numeral 46 in FIG. 1 is a pressure reducing valve, and reference numeral 47 is a feed water temperature sensor for detecting the feed water temperature.

  The hot water supply circuit 5 supplies either one of two types of hot water supplied to the upstream end 52 of the main hot water supply passage 51 to the hot water tap 7. That is, hot water supplied to the upstream end 52 of the main hot water supply passage 51 through the tank water proportional valve 66 after auxiliary heating by the auxiliary heat source device (for example, instantaneous heating type hot water heater) 6, and the hot water storage tank 3 through the top connection passage 53. Either one of the two types of hot water, which is taken out from the top and supplied to the upstream end 52 of the main hot water supply channel 51, can be supplied. A mixing valve 54 is interposed downstream of the main hot water supply passage 51 and is mixed with water from the branch water supply passage 44 so that the temperature can be adjusted to a predetermined temperature. Furthermore, hot water for hot water filling can be supplied to a bathtub 102 described later through a pouring channel 55 branched from the downstream end side of the main hot water supply channel 51.

  The auxiliary heat source unit 6 is supplied with hot water from the bottom outlet path 12 or the top outlet path 13 on the water inlet side, supplies hot water to the main hot water supply path 51 after auxiliary heating, or supplies hot water as a heat source to the external heat load circuit 8. You can do it. That is, the bottom outlet channel 12 has an upstream end 121 connected to the bottom 32 of the hot water storage tank 3, the downstream side of the main water supply channel 41, and the downstream end of the heat source supply channel 81 of the external heat load 8, respectively. The auxiliary heat source unit 6 is connected to the water inlet side via a three-way switching valve 61. Between the three-way switching valve 61 and the auxiliary heat source machine, a heating circulation pump 62, a flow rate sensor 63, and an auxiliary heat source machine inlet temperature sensor 64 are interposed. Reference numeral 65 in FIG. 1 denotes an auxiliary heat source machine outlet temperature sensor for detecting the hot water temperature after auxiliary heating. The top outlet 13 is branched from the middle of the top connecting passage 53, the downstream end is connected to the three-way switching valve 61, and hot water taken out from the top of the hot water storage tank 3 is passed through the three-way switching valve 61. The auxiliary heat source unit 6 can be supplied to the incoming water side.

  The external heat load circuit 8 is branched in two directions on the downstream side of the heat source supply path 81, one passing through a heat exchanger 82 for heat exchange heating of hot water circulated and supplied to the heating circuit 9, and the other being a reheating circuit. 10 is connected to the upstream end 121 of the bottom outlet passage 12 after passing through the heat exchanger 83 for replenishing and heating the bathtub water circulated and supplied to the heat exchanger by heat exchange heating and passing through the open / close solenoid valves 84 and 85, respectively. Yes. That is, hot water heated at a predetermined temperature by the auxiliary heat source unit 6 is supplied to the heat exchangers 82 and / or 83 as a heat source, and after the heat exchange heating, the heat is again heated by the auxiliary heat source unit 6 through the bottom outlet path 12 and then heated. A heat source for heat exchange heating can be circulated and supplied to the exchangers 82 and / or 83.

  The hot water heating circuit 9 heats and heats a heat medium (warm water) as a heating heat source in the heating circuit 91 with a heat exchanger 82, and the hot water heated to a predetermined temperature is heated to a high temperature heating terminal (for example, a bathroom dryer) 92. Or it is designed to circulate and supply to a low-temperature heating terminal (for example, floor heating) 93. Then, after the heat is radiated from the high temperature heating terminal 92 and the low temperature heating terminal 93, the heat is returned to the heat exchanger 82 through the heating expansion tank 94 and the heating pump 95, and reheated. Reference numeral 96 in FIG. 1 is a heating forward temperature sensor that detects the temperature of hot water heated and exchanged by the heat exchanger 82, reference numeral 97 is a heating return temperature sensor provided at the bottom of the heating expansion tank 94, and reference numeral 98 is This is a heat operated valve that is opened (ON) / closed (OFF) in order to switch supply / cutoff of low-temperature water as a heating heat source to the low-temperature heating terminal 93. Reference numeral 99 denotes hot water after heat exchange heating from the heat exchanger 82. This bypass path bypasses the high-temperature heating terminal 92 and supplies it directly to the heating / expansion tank 94.

  The reheating circuit 10 operates the reheating pump 101 to circulate hot water in the bathtub 102 through the recirculation circuit 103 and the heat exchanger 83, and reheats by heat exchange heating in the heat exchanger 83. It comes to whisper. A pouring passage 55 branched from the main hot water supply passage 51 is connected to the reheating circulation passage 103, and hot water whose temperature is adjusted by the mixing valve 54 is supplied to the bathtub 102 via the pouring passage 55. Hot water filling is possible.

  1 are freeze prevention heaters, respectively, and these freeze prevention heaters 15, 15,... Are installed in various places such as a water supply passage 41 that tends to be low in temperature compared to other pipes. Under the grid interconnection operation mode described later, a predetermined time (for example, 50 seconds) at each predetermined timing when a condition such that the detected temperature such as the environmental temperature is equal to or lower than the predetermined temperature is satisfied by the freeze prevention operation control of the controller 14. Only intermittently (ON).

  The above cogeneration apparatus is normally driven by a grid-connected operation mode in which power is supplied mainly from a commercial power system, while it is driven by a self-sustaining operation mode in which power is generated from the power generation unit 2 when a power failure occurs in the commercial power system. It is configured to be. The cogeneration apparatus is controlled by the controller 14 in response to the output of input setting signals and operation signals from the remote controller 141 and the output of detection signals from various temperature sensors. For such operation control, the controller 14 includes an exhaust heat recovery operation control unit, a hot water supply operation control unit, an external heat load operation control unit, a heating operation control unit, a bath operation control unit for hot water filling and reheating, And a normal operation control unit for performing operation control under the grid interconnection operation mode, including the freeze prevention operation control unit, and the various operation controls described above when the commercial power system is switched to the independent operation mode when a power failure occurs. And a self-sustained operation control unit that performs operation control by adding a change for reducing power consumption.

  Hereinafter, the heating operation control and the freeze prevention operation control, which are characteristic control portions of the present embodiment, will be described in detail separately for the case of the normal operation control unit and the case of the independent operation control unit. First, the heating operation control in the case of the normal operation control unit will be described. When the operation of the low temperature heating terminal (floor heating) 93 is turned on by the user, the heating circulation pump 62 and the heating pump 95 are turned on. Then, the combustion control of the auxiliary heat source unit 6 is started. Thereby, hot water (heat source) auxiliary-heated by the auxiliary heat source device 6 is circulated and supplied to the heat exchanger 82, whereby the hot water supplied through the heating circuit 91 is heat-exchanged and heated. The hot water after the heat exchange heating enters the heating / expansion tank 94 through the bypass 99, and then a part of the hot water is supplied to the low-temperature heating terminal 93 and then returned to the heating / expansion tank 94, while the other part is the heat exchanger. After being supplied to 82 and subjected to heat exchange heating, it is put back into the heating expansion tank 94. At this time, based on the temperature detection by the heating return temperature sensor 97, the floor heating heat source (low temperature water) supplied to the low temperature heating terminal 93 is controlled to have the temperature (first temperature; for example, 60 ° C.). . As described above, the operation of the high temperature heating terminal 92 is turned off, only the operation of the low temperature heating terminal 93 is turned on, and the low temperature heating terminal 93 is supplied with only one type of low temperature water (low temperature). This is the case of supply. Then, ON / OFF control of the thermal valve 98 according to the heating temperature adjustment level set by the user in the low-temperature heating terminal 93 is performed, and the heating temperature is controlled to the set heating temperature adjustment level. For example, as shown in FIG. 2, if the heating temperature adjustment level is set to the maximum (MAX), the OFF time is set to zero and the thermal valve 98 is continuously turned ON. In this case, as long as the thermal valve 98 is in the ON state, the heating circulation pump 61 and the heating pump 95 are continuously operated, and accordingly, electric power is continuously consumed. If the heating temperature adjustment level is set to the minimum (MIN), the thermal valve 98 is opened for a predetermined ON time tp so that the low temperature water is supplied to the low temperature heating terminal 93 so as to reach the heating temperature of the heating temperature adjustment level. On the other hand, the thermal operation valve 98 is closed for a predetermined OFF time tc so as to switch off the supply of low-temperature water. This is repeated every certain cycle time (1 cycle time = tp + tc; for example, 1 cycle time = 20 minutes). That is, by intermittently supplying low-temperature water to the low-temperature heating terminal 93, a predetermined heating temperature control level is achieved. In addition, the above description is the control in the steady state when only the low temperature heating terminal 93 is operated and operated, and particularly in the initial stage of starting the operation of the low temperature heating terminal 93, the floor heating which is the low temperature heating terminal is cooled. In consideration of starting operation, the following control may be performed. That is, in order to quickly raise the temperature of the floor heating, which is a low-temperature heating terminal, from a cold state, only hot water of higher temperature is supplied to the low-temperature heating terminal instead of the low-temperature water of the first temperature only at the beginning of the operation operation. In the steady state after the heating temperature reaches the predetermined temperature, the above-described heating operation control for supplying the low-temperature water at the first temperature is continued.

  In addition to the low temperature heating terminal 93, when the operation of the high temperature heating terminal 92 is turned on by the user and the low temperature heating terminal 93 and the high temperature heating terminal 92 enter the heating operation at the same time, heating is performed after heat exchange heating in the heat exchanger 82. The temperature of the hot water discharged to the circulation path 91 is controlled based on the temperature detected by the heating-out temperature sensor 96 so that it becomes the temperature of the heat source (high temperature water) for the high temperature heating terminal 92 (second temperature; for example, 80 ° C.). The The high-temperature water is first supplied to the high-temperature heating terminal 92, and the hot water that has been cooled down after heat radiation is returned to the heating / expansion tank 94. 93, and the other part is heat-exchanged again by the heat exchanger 82. In this case, the high-temperature heating terminal 92 is supplied with high-temperature water, and the low-temperature heating terminal 93 is supplied with hot water having a temperature lower than that of the high-temperature water. The temperature of the low-temperature water supplied to 93 becomes higher than 60 ° C. in the case of the one temperature (low temperature) supply. For this reason, for example, even when the heating temperature adjustment level is the maximum, the thermal valve 98 is not maintained continuously ON but is repeatedly turned ON by turning it OFF for a predetermined time every cycle time. So, make the same heating temperature control level. That is, in order to achieve the same heating temperature control level, in the case of two temperature (low temperature / high temperature) supply in which the low temperature heating terminal 93 and the high temperature heating terminal 92 are simultaneously operated, the ON time tp for each cycle time is set. The control mode can be switched to a shorter control mode, which is called an ON time reduction mode. The ratio of thermal valve OFF time per cycle time (OFF duty ratio) for setting the heating degree by floor heating to a predetermined heating temperature control level is not limited to using a calculation method, for example, floor heating is performed. It may be determined by a test in the laboratory, stored in advance in the controller 14 as a table value based on a combination of low temperature water and high temperature water, read out from this table value, and ON / OFF control of the thermal valve 98 may be performed.

  Next, when a power failure occurs in the commercial power system, the power supply is switched to that from the power generation unit 2, and various controls by the controller 14 are switched to the self-sustaining operation mode, the heating operation control described above is performed as follows. Will be changed. That is, even when only the operation of the low-temperature heating terminal 93 is turned on, heat exchange is performed so that the heat source to be supplied is not the low-temperature water but high-temperature water (80 ° C.) for the high-temperature heating terminal 92. The heat source supply to the heater 82 is changed, and the OFF duty ratio in the ON time reduction mode is changed to be used as the OFF duty ratio used for the ON / OFF control of the thermal valve 98 in the heating operation control. Accordingly, in the case of one temperature (low temperature) supply, for example, if the heating temperature adjustment level is maximum, it becomes necessary to continuously operate the heating circulation pump 62 and the heating pump 95, which is insufficient. Even within the power supply, considerable power consumption will continue for these pump operations. By changing to the control as described above, an OFF time can be generated. During the OFF time, Other power loads can use the power.

  In the change control, the change is made so that the OFF duty ratio in the ON time reduction mode is used, but the change control can be performed so that the OFF time can be further increased. That is, even when only the operation of the low temperature heating terminal 93 is turned on, not the low temperature water (60 ° C.) but the high temperature water (80 ° C.) for the high temperature heating terminal 92 is supplied as the heat source to be supplied. Thus, the high temperature water (80 ° C.) discharged from the heat exchanger 82 enters the heating / expansion tank 94 through the bypass 99 without being supplied to the high temperature heating terminal 92 and is supplied to the low temperature heating terminal 93. Therefore, in the case of supplying the two temperatures (low temperature and high temperature) in the ON time shortening mode, the low temperature heating terminal 92 is subjected to the heat dissipation in the high temperature heating terminal 92 because the heat does not pass through the high temperature heating terminal 92. The hot water temperature supplied to the low-temperature heating terminal 93 is higher (eg, 76 ° C.) than the hot water temperature (eg, 72 ° C.) supplied to 93. For this reason, for example, even when the heating temperature control level is set to the maximum, the OFF time tc is set to be shorter than the ON time shortening mode (in the case of two temperature (low temperature / high temperature) supply; see FIG. 2) by the normal operation control unit. It becomes possible to make it longer (the OFF duty ratio is larger) (in the case of supplying one temperature (high temperature); see the lowermost stage in FIG. 2). Thereby, the amount of suppression of power usage (amount of reduction in power consumption) can be further increased. When the circulation pump 62 for heating and the heating pump 95 are continuously operated, the anti-freezing heaters 15, 15,... Cannot be energized, but the anti-freezing heaters 15, 15,. It becomes possible to perform the freeze prevention operation by reliably supplying power.

  In the above embodiment, the hot water supply amount (heat supply amount for heat radiation) to the low temperature heating terminal 93 is changed according to the heating temperature adjustment level by ON / OFF control of the thermal valve 98, For example, the hot water supply amount can be changed and controlled by changing the rotation speed of the heating pump 95. In this case, if the number of revolutions of the heating pump 95 is changed to a lower side, the power consumption for driving the heating pump 95 can also be reduced, whereby the freeze prevention heaters 15, 15. It may be possible to energize ... Further, as a result of the suppression of power consumption (reduction of power consumption) by the change control during the self-sustained operation, if the consumption of generated power from the power generation unit 2 becomes smaller than a predetermined determination value, Freezing prevention heater 15, 15. It is only necessary to start the freeze prevention operation control by energization of ..., and due to the use of power by other power loads, the consumption of the generated power from the power generation unit 2 can be temporarily larger than a predetermined judgment value. For example, the start of the freeze prevention operation can be made to wait until it is resolved.

2 Power Generation Unit 3 Hot Water Storage Tank 6 Auxiliary Heat Source Machine 9 Hot Water Heating Circuit (Hot Water Heating Device)
14 Controller (Heating operation control unit, freeze prevention operation control unit)
92 High temperature heating terminal 93 Low temperature heating terminal

A three-way switching valve 114 is interposed in the middle of the introduction path 112, and a bypass path 115 branched from the middle position of the outlet path 111 so as to bypass the hot water storage tank 3 is connected to the three-way switching valve 114. ing. The three-way switching valve 114 is maintained in an exhaust heat recovery switching state in which the outlet 31 of the hot water storage tank 3 and the exhaust heat recovery heat exchanger 22 are communicated with each other during the exhaust heat recovery operation. 1 is a heat exchanger inlet temperature sensor for detecting the hot water temperature before heat exchange heating, and 117 is a heat exchanger outlet temperature sensor for detecting the hot water temperature after heat exchange heating. is there.

Hereinafter, the heating operation control and the freeze prevention operation control, which are characteristic control portions of the present embodiment, will be described in detail separately for the case of the normal operation control unit and the case of the independent operation control unit. First, the heating operation control in the case of the normal operation control unit will be described. When the operation of the low temperature heating terminal (floor heating) 93 is turned on by the user, the heating circulation pump 62 and the heating pump 95 are turned on. Then, the combustion control of the auxiliary heat source unit 6 is started. Thereby, hot water (heat source) auxiliary-heated by the auxiliary heat source device 6 is circulated and supplied to the heat exchanger 82, whereby the hot water supplied through the heating circuit 91 is heat-exchanged and heated. The hot water after the heat exchange heating enters the heating / expansion tank 94 through the bypass 99, and then a part of the hot water is supplied to the low-temperature heating terminal 93 and then returned to the heating / expansion tank 94, while the other part is the heat exchanger. After being supplied to 82 and subjected to heat exchange heating, it is put back into the heating expansion tank 94. At this time, based on the temperature detection by the heating return temperature sensor 97, the floor heating heat source (low temperature water) supplied to the low temperature heating terminal 93 is controlled to have the temperature (first temperature; for example, 60 ° C.). . As described above, the operation of the high temperature heating terminal 92 is turned off, only the operation of the low temperature heating terminal 93 is turned on, and the low temperature heating terminal 93 is supplied with only one type of low temperature water (low temperature). This is the case of supply. Then, ON / OFF control of the thermal valve 98 according to the heating temperature adjustment level set by the user in the low-temperature heating terminal 93 is performed, and the heating temperature is controlled to the set heating temperature adjustment level. For example, as shown in FIG. 2, if the heating temperature adjustment level is set to the maximum (MAX), the OFF time is set to zero and the thermal valve 98 is continuously turned ON. In this case, as long as the thermal valve 98 is in the ON state, the heating circulation pump 62 and the heating pump 95 are continuously operated, and accordingly, electric power is continuously consumed. If the heating temperature adjustment level is set to the minimum (MIN), the thermal valve 98 is opened for a predetermined ON time tp so that the low temperature water is supplied to the low temperature heating terminal 93 so as to reach the heating temperature of the heating temperature adjustment level. On the other hand, the thermal operation valve 98 is closed for a predetermined OFF time tc so as to switch off the supply of low-temperature water. This is repeated every certain cycle time (1 cycle time = tp + tc; for example, 1 cycle time = 20 minutes). That is, by intermittently supplying low-temperature water to the low-temperature heating terminal 93, a predetermined heating temperature control level is achieved. In addition, the above description is the control in the steady state when only the low temperature heating terminal 93 is operated and operated, and particularly in the initial stage of starting the operation of the low temperature heating terminal 93, the floor heating which is the low temperature heating terminal is cooled. In consideration of starting operation, the following control may be performed. That is, in order to quickly raise the temperature of the floor heating, which is a low-temperature heating terminal, from a cold state, only hot water of higher temperature is supplied to the low-temperature heating terminal instead of the low-temperature water of the first temperature only at the beginning of the operation. In the steady state after the heating temperature reaches the predetermined temperature, the above-described heating operation control for supplying the low-temperature water at the first temperature is continued.

Claims (6)

A power generation unit, a hot water storage tank that collects exhaust heat generated during power generation operation in the power generation unit and stores it as hot water, and a hot water heating device that performs heating operation by supplying hot water using hot water stored in the hot water storage tank The hot water heating apparatus supplies a low temperature water having a first temperature to dissipate heat, and a high temperature heating to dissipate heat by supplying high temperature water having a second temperature higher than the first temperature. It is equipped with a terminal and a heating operation control unit that executes operation control related to the supply of hot water, and is normally driven by power supply by grid connection operation with the commercial power system, while a power failure occurs in the commercial power system. In the cogeneration device configured to be driven by a self-sustaining operation that receives supply of generated power from the power generation unit when it occurs,
When the heating operation control unit is driven by the grid connection operation, when only the low temperature heating terminal is operated, the low temperature heating terminal is supplied with low temperature water having the first temperature in principle. On the other hand, when driven by the self-sustained operation, it is configured to change and control so as to supply high-temperature water having the second temperature to the low-temperature heating terminal.
Cogeneration equipment characterized by that. The cogeneration apparatus according to claim 1,
The heating operation control unit is a cogeneration apparatus configured to change and control a supply amount to the low temperature heating terminal according to a heating temperature control level in the low temperature heating terminal. The cogeneration apparatus according to claim 2,
The heating operation control unit is configured to ON / OFF control hot water supply to the low temperature heating terminal and to change and control a ratio of ON time / OFF time per cycle time. . It is a cogeneration apparatus in any one of Claims 1-3,
A cogeneration apparatus comprising a combustion heating type auxiliary heat source device for heating a heat source for heating hot water supplied to the hot water heating apparatus. A cogeneration apparatus according to any one of claims 1 to 4,
A cogeneration apparatus including a freeze prevention operation control unit that receives a drive power supply and executes freeze prevention operation control. The cogeneration apparatus according to claim 5,
When the freeze prevention operation control unit is driven by the self-sustained operation, the freeze prevention operation control unit is configured to wait for execution of the freeze prevention operation control when the power consumption of the generated power supplied from the power generation unit exceeds a predetermined value. A cogeneration device.

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