Hot water supply method, system, program, recording medium and control unit

Abstract

To achieve high-temperature hot water supply acquired by a first heat source machine by suppressing power consumption within a system of generated power of a power generation part when an AC power source in interrupted in a hot water supply system including at least a first heat source machine and a second heat source machine.SOLUTION: A hot water supply method including at least a first heat source machine (an FA unit 4) and a second heat source machine (BB6) to supply preheated water (HW) from the first heat source machine to the second heat source machine, performing hot water supply from the second heat machine includes the steps of: performing heat exchange of exhaust heat of a power generation part (14) into a heat medium (HM2) to store the heat medium in a heat storage tank (18); performing heat exchange of the heat of the heat medium of the heat storage tank into feed water (W) to generate preheated water; and stopping power supply to the second heat source machine, continuing the power generation of the power generation part and supplying the preheated water of the first heat source machine, changing a setting temperature of the preheated water into a value higher than a value before the interruption of the AC power source, and controlling the temperature of the preheated water to the setting temperature when an AC power source (a commercial power source 8) is interrupted during power generation of the power generation part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a hot water supply control technique for a hot water supply system including a heat source unit that includes a SOFC (Solid Oxide Fuel Cell) as a heat source and another heat source unit, for example. [Background technology]

[0002] For example, a hot water supply system that combines a first heat source unit that uses the exhaust heat of an SOFC as a heat source with a second heat source unit (auxiliary heat source unit) that uses the combustion heat of fuel gas as a heat source is already in practical use.

[0003] In a hot water supply system equipped with multiple heat source units that use different heat sources, there is system control that links the individual heat source units, and standalone control that does not link the operation of the individual heat source units. For example, with this standalone control, an optional second heat source unit can be installed next to the hot water outlet side of a first heat source unit that includes an SOFC, making it possible to supply hot water independently of the first and second heat source units.

[0004] With regard to such hot water supply systems, in which a heat source unit equipped with a fuel cell system is connected to an auxiliary heat source unit and preheated water is supplied from the heat source unit to the auxiliary heat source unit, it is known that the temperature of the preheated water received by the auxiliary heat source unit is controlled on the upstream heat source unit side (for example, Patent Document 1).

[0005] In the case where the control means of each heat source unit are not linked, a preheating operation is known in which the temperature of the water supplied from the heat source unit in the preceding stage to the heat source unit in the following stage is raised by a certain temperature, and when it is equal to or higher than a preset lower limit temperature, the temperature is raised by a certain temperature, and when it is below the lower limit temperature, the temperature is raised to the lower limit (for example, Patent Document 2). Paragraph 0025 of Patent Document 2 states that in the event of a power outage, the high-temperature hot water outlet avoidance solenoid valve opens, allowing clean water to be supplied to the hot water outlet passage, and the hot water is used to lower the hot water outlet temperature. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2018-4224 A [Patent Document 2] JP 2019-7691 A Summary of the Invention [Problem to be solved by the invention]

[0007] As described above, if the first heat source unit is equipped with a power generation unit including SOFC, and the first heat source unit and the second heat source unit are systemized and linked, and operation can be continued with the power generation output of the power generation unit, even if the AC power supply is interrupted, the preheated water from the first heat source unit can be fed to the second heat source unit, and hot water at the set hot water temperature can be supplied by the heating operation of this second heat source unit. Such a systemization has restrictions such as the first heat source unit and the second heat source unit having common specifications, and when the second heat source unit is retrofitted, for example, when the second heat source unit is changed to a unit made by another manufacturer, there are problems such as the freedom of model selection being hindered. In addition, when the first heat source unit is retrofitted to an existing second heat source unit, the second heat source unit may be made by a different manufacturer, or even if it is made by the same manufacturer, the communication specifications may be different, making it difficult to standardize the specifications of the first heat source unit and the second heat source unit.

[0008] However, in the event of a disaster or other such event where the AC power source is lost, consuming the power generated by the power generation unit with the second heat source unit is an issue in terms of power saving. In addition, if the first and second heat source units are not controlled in conjunction with each other, not only will the second heat source unit be unable to provide a backup function in the event of an AC power outage, but if the first heat source unit is operated solely by AC power, the preheated water supply function will also be impaired.

[0009] In the event of a power outage, if the first heat source unit is operated with the power generated by the power generation unit, it is possible to supply the preheated water to the second heat source unit, but the set temperature of the preheated water is lower than the set outlet temperature, for example 30°C, which poses the problem that the outlet temperature is low. Also, if the power generation unit continues to generate electricity, the heat storage tank will become full, and if this state continues, there is the problem that the usability of thermal energy will decrease.

[0010] The inventors discovered that when the AC power supply is interrupted while the power generation unit is generating electricity, if the operation of the second heat source unit is stopped and the power generation unit continues to generate electricity, the generated electricity can be effectively used for general power supply, the utilization of the thermal energy stored in the thermal storage tank can be increased, and hot water can be supplied using preheated water.

[0011] Therefore, based on the above-mentioned problems and findings, the object of the present disclosure is to provide a hot water supply system including at least a first heat source unit and a second heat source unit, such that when the AC power supply is interrupted, the power consumption within the system of the generated power by the power generation unit is reduced, and high-temperature hot water supply is realized using pre-heated water obtained by the first heat source unit. [Means for solving the problem]

[0012] In order to achieve the above object, according to one aspect of a hot water supply method of the present disclosure, there is provided a hot water supply method including at least a first heat source unit and a second heat source unit, supplying preheated water from the first heat source unit to the second heat source unit, and supplying hot water from the second heat source unit, the hot water supply method including a step of exchanging exhaust heat from a power generation unit with a heat medium and storing the heat medium in a heat storage tank, a step of exchanging heat of the heat medium in the heat storage tank with supply water to generate the preheated water, and during power generation by the power generation unit, When the AC power source is supplying power, the second heat source unit receives the preheated water from the first heat source unit, and supplies hot water, which is either the hot water that has passed through the heat exchanger or the preheated water that has passed through the bypass passage, or hot water that is a mixture of the hot water and the preheated water, according to an opening degree of a mixing valve that changes an inflow ratio between the heat exchanger of the second heat source unit and a bypass passage that bypasses the heat exchanger, When the AC power supply is interrupted, the power supply to the second heat source unit is stopped, and the power generation of the power generation unit is continued and the power supply to the first heat source unit is stopped. to the second heat source unit The preheated water is supplied, the set temperature of the preheated water is changed to a value higher than the value before the power outage of the AC power supply, and the temperature of the preheated water is controlled to the set temperature. At the same time, the preheated water supplied to the second heat source unit is entirely passed through the bypass passage to supply hot water from the second heat source unit. and

[0013] In order to achieve the above object, according to one aspect of a hot water supply system of the present disclosure, there is provided a hot water supply system including at least a first heat source unit and a second heat source unit, the first heat source unit supplies preheated water to the second heat source unit, and the second heat source unit supplies hot water, The first heat source unit, a power generation unit, a first heat exchange unit that exchanges heat between a heat medium and exhaust heat generated by power generation in the power generation unit, a heat storage tank that stores the heat medium, and a second heat exchange unit that exchanges heat between the heat of the heat medium supplied from the heat storage tank and supply water to generate the preheated water. Equipped with , The second heat source unit includes a heat exchanger that heats the preheated water supplied from the first heat source unit, a bypass passage that bypasses the heat exchanger, and a mixing valve that is connected to the heat exchanger and the bypass passage and changes the ratio of the preheated water flowing into the heat exchanger and the bypass passage depending on an opening degree of the mixing valve, and when an AC power source is supplied, the second heat source unit that receives the preheated water from the first heat source unit supplies hot water, either hot water that has passed through the heat exchanger or the preheated water that has passed through the bypass passage, or hot water obtained by mixing the hot water and the preheated water, depending on an opening degree of the mixing valve, When the AC power supply is interrupted, the power supply to the second heat source unit is stopped, and the power generation of the power generation unit is continued and the power supply to the first heat source unit is stopped. to the second heat source unit The preheated water is supplied, the set temperature of the preheated water is changed to a value higher than the value before the power outage of the AC power supply, and the temperature of the preheated water is controlled to the set temperature. At the same time, the preheated water supplied to the second heat source unit is entirely passed through the bypass passage to supply hot water from the second heat source unit. and a control unit for controlling the In this hot water supply system, the power generation unit includes a heat exchanger that exchanges heat between the exhaust heat and the heat medium. This may include the ability to

[0014] This hot water supply system may further include a power generation monitoring unit that monitors the power generation of the power generation unit, and a power supply monitoring unit that monitors the power supply of the AC power source, and when a power outage occurs in the AC power source while the power generation unit is generating electricity, the control unit may continue generating electricity from the power generation unit.

[0015] This hot water supply system may further comprise a remote control unit having a function of instructing the control unit to continue power generation of the power generation unit when a power outage occurs in the AC power supply.

[0016] This hot water supply system may further comprise a remote control unit that has a function of selecting a set temperature of the preheated water and instructs the control unit of the set temperature when the AC power supply is interrupted.

[0017] In order to achieve the above object, according to one aspect of a program of the present disclosure, there is provided a program to be executed by a computer, the program including at least a first heat source unit and a second heat source unit, the first heat source unit supplying preheated water to the second heat source unit, and a function of controlling an opening degree of a mixing valve that changes an inflow ratio between the heat exchanger of the second heat source device and a bypass path that bypasses the heat exchanger when the AC power source is supplying power, to thereby control the opening degree of a mixing valve that changes an inflow ratio between the heat exchanger of the second heat source device and a bypass path that bypasses the heat exchanger. From the second heat source unit Either the hot water that has passed through the heat exchanger or the preheated water that has passed through the bypass passage, or the hot water that is a mixture of the hot water and the preheated water Hot water supply Let The function of the power generation unit during power generation The above When the AC power supply is interrupted, the power supply to the second heat source unit is stopped, and the power generation of the power generation unit is continued and the power supply to the first heat source unit is stopped. to the second heat source unit a function of supplying the preheated water and changing the set temperature of the preheated water to a value higher than the value before the power outage of the AC power supply; and a function of controlling the temperature of the preheated water to the changed set temperature. At the same time, the preheated water supplied to the second heat source unit is entirely passed through the bypass passage to supply hot water from the second heat source unit. and causing the computer to execute the functions of:

[0018] In order to achieve the above object, one aspect of a recording medium of the present disclosure is a recording medium storing control information used in a control unit of the hot water supply system, or storing the program.

[0023] In order to achieve the above object, according to one aspect of the control unit of the present disclosure, a control unit or a remote control included in the hot water supply system To the department Includes any of the included control units. Effect of the Invention

[0024] According to the present disclosure, any of the following effects can be obtained. (1) In a hot water supply system including at least a first heat source unit and a second heat source unit, in which preheated water is supplied from the first heat source unit to the second heat source unit, when an AC power outage occurs, the second heat source unit can be stopped to reduce power consumption, and hot water at the desired temperature can be supplied using the preheated water from the first heat source unit.

[0025] (2) If the power generation unit is generating electricity, in the event of a power outage, the power generation unit can continue to generate electricity and the preheated water obtained by the first heat source unit can be heated to provide hot water.

[0026] (3) The exhaust heat generated by the power generation unit is exchanged with a heat medium and stored in the heat transfer medium, so that the stored heat energy can be effectively utilized in the event of a power outage.

[0027] (4) Even if the heat storage tank, which stores the exhaust heat of the power generation unit using a heat medium, becomes full, the tank can quickly recover from the full storage state by using the heat for hot water supply without dissipating the heat. [Brief description of the drawings]

[0028] [Figure 1] 1 is a diagram showing a hot water supply system according to a first embodiment; [Diagram 2] FIG. 2 is a diagram showing a backup heat source unit. [Diagram 3] FIG. 2 is a diagram illustrating one function of the backup heat source unit. [Figure 4] FIG. 2 is a diagram illustrating hardware of an FC unit control unit and a remote control unit. [Diagram 5] 2 shows an example of a control function of the FC unit control section. [Figure 6] 4 is a flowchart showing a procedure for controlling the temperature of preheated water. [Figure 7] FIG. 11 is a diagram showing changes in the set temperature and outlet temperature of preheated water. [Figure 8] 13 is a flowchart showing a processing procedure for controlling the temperature of preheated water in a hot water supply system according to a second embodiment. [Figure 9] 11 is a diagram showing changes in the set temperature of preheating water and changes in the outlet water temperature. FIG. [Figure 10] FIG. 1 is a diagram showing mixing control using a distribution valve according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] First Embodiment Fig. 1 shows a hot water supply system according to a first embodiment. This hot water supply system is one example of the hot water supply system of the present disclosure, and the present disclosure is not limited to the configuration shown in Fig. 1.

[0030] The hot water supply system 2 includes at least a first heat source unit and a second heat source unit, the first heat source unit including, for example, a FC (Fuel Cell) unit 4, and the second heat source unit including, for example, a backup heat source unit (hereinafter simply abbreviated as "BB") 6. The FC unit 4 exchanges exhaust heat generated by power generation with feed water W to generate preheated water HW1 or preheated water HW2, and supplies either of the preheated water HW1 or HW2 to the BB6. The preheated water HW1 is supplied to the BB6 by being drawn from the FC unit 4 when power is supplied from the commercial power source 8. In contrast, the preheated water HW2 is heated by the FC unit 4 when the commercial power source 8 is experiencing a power outage, and is passed through the BB6, which is not operating. The commercial power source 8 is an example of a commercial AC power source that supplies power to the FC unit 4, BB6, and the like, as well as any other AC power source.

[0031] During power supply from the commercial power source 8, the preheated water HW1 is subjected to backup heating from the BB6 and can be heated to the set hot water outlet temperature Tm, so the set temperature Tc of the preheated water HW1 may be a value Tc1 lower than the set hot water outlet temperature Tm. This Tc1 is, for example, 15 to 30°C. In contrast, when the commercial power source 8 experiences a power outage, the operation of the BB6 is stopped and the backup heating is not obtained, so the set temperature Tc of the preheated water HW2 is set to a value Tc2 close to the set hot water outlet temperature Tm. Tc2 is, for example, 40°C or higher.

[0032] <FCユニット4> The FC unit 4 illustrated in FIG. 1 includes a power adjustment section 10, an FC unit control section (hereinafter simply referred to as the “control section”) 12, a power generation section 14, a first heat exchanger 16, a heat storage tank 18, a second heat exchanger 20, etc.

[0033] The power adjustment unit 10 is linked to a power generation system including a commercial power source 8 and a power generation unit 14. The linking functions of the power adjustment unit 10 include: a) Receiving power from commercial power source 8 b) Transmission of the generated power from the power generation unit 14 to the commercial power source 8 c) Supply of power from the commercial power source 8 to the functional parts of the FC unit 4 including the control part 12 d) When the commercial power source 8 is interrupted, power is supplied to the functional parts of the FC unit 4, including the control part 12, by the power generated by the power generation part 14 during power generation. e) Controls associated with these etc.

[0034] The control unit 12 is equipped with a computer and performs various controls by information processing. f) Heat storage control of heat transfer medium HM2 g) Generation of preheated water (HW) h) Power supply monitoring of commercial power source 8 i) Power generation monitoring of the power generation unit 14 j) Maintaining power generation of the power generation unit 14 k) Heat storage control of heat storage tank 18 l) Temperature setting and control of preheated water HW m) Control of information presentation The control unit 12 is connected to a remote control unit 22 for remote control of temperature setting and the like.

[0035] The power generation unit 14 is, for example, configured with a SOFC (solid oxide fuel cell) and controlled by the control unit 12, and generates exhaust gas HM1 by power generation. The power generated by the power generation unit 14 is supplied to the power adjustment unit 10 and used as a general power source. The exhaust gas HM1 is supplied to the heat exchanger 16 and used as a heat source for heating the heat medium HM2.

[0036] The heat exchanger 16 is an example of a first heat exchange unit. The heat exchanger 16 exchanges heat between the exhaust gas HM1 and the heat medium HM2 in the heat storage tank 18 to heat the heat medium HM2. A circulation path 24 and a circulation pump 26 for circulating the heat medium HM2 to the heat exchanger 16 are installed between the heat exchanger 16 and the heat storage tank 18. During power generation, the circulation pump 26 is controlled by the control unit 12, and the heat medium HM2 taken out from the lower part of the heat storage tank 18 is circulated to the heat exchanger 16 and returned to the upper part of the heat storage tank 18. As a result, the exhaust heat of the power generation unit 14 is stored in the heat storage tank 18 by the heat medium HM2.

[0037] The heat storage tank 18 is a container for storing the heat medium HM2, and stores heat by the heat medium HM2 heated by exhaust heat. The heat medium HM2 may be water, oil, or other heat medium. The heat storage tank 18 is provided with a temperature sensor 28, which detects the temperature of the upper layer of the heat medium HM2.

[0038] The heat exchanger 20 exchanges heat between the heat of the heat medium HM2 and the feed water W based on the demand for hot water supply, and heats the feed water W to generate preheated water HW. Between the heat exchanger 20 and the heat storage tank 18, a circulation path 30 and a circulation pump 32 are installed to circulate the heat medium HM2 to the heat exchanger 20. The heat exchanger 20 is an example of a second heat exchange unit. During hot water supply, the circulation pump 32 is controlled by the control unit 12, and the heat medium HM2 taken out from the upper part of the heat storage tank 18 is circulated to the heat exchanger 20 and returned to the lower part of the heat storage tank 18. As a result, the feed water W is heated by the heat of the heat medium HM2. A temperature sensor 34 is installed in the circulation path 30, and this temperature sensor 34 detects the temperature of the heat medium HM2 used in the heat exchange.

[0039] Feedwater W flows from a water supply passage 36 to the heat exchanger 20, and preheated water HW (=HW1 or HW2) obtained by heating the feedwater W flows into a hot water outlet passage 38. The temperature of the feedwater W entering the water supply passage 36 is detected by a temperature sensor 40, and the amount of the water is detected by a water amount sensor 42, and these detection information are provided to the control unit 12. The distribution valve 44 and the hot water outlet passage 38 are connected via a bypass passage 46, and the feedwater W branched off into the bypass passage 46 is mixed with the preheated water HW, which is the feedwater W after heating. This mixing adjusts the temperature of the preheated water HW. In other words, a mixing unit 45 that adjusts the temperature of this preheated water HW includes, as an example, the water amount sensor 42, the distribution valve 44, the water control valve 50, and the bypass passage 46.

[0040] The temperature of the preheated water HW coming out of the heat exchanger 20 is detected by a temperature sensor 48. The amount of the preheated water HW mixed with the feed water W is controlled by a water control valve 50 under the control of the control unit 12, and the temperature of the preheated water HW coming out of the FC unit 4 is detected by a temperature sensor 52 and provided to the control unit 12.

[0041] <Remote control unit 22> The remote control unit 22 is associated with the control unit 12 and is used for initial setting of the set temperature Tc of the preheated water HW, change during a power outage, and other information presentation.

[0042] <BB (backup heat source machine) 6> BB6 is, for example, a water heater independent of the FC unit 4. During hot water supply, preheated water HW is supplied from the FC unit 4. The BB control unit 54 is equipped with a computer. When the commercial power supply 8 is powered on, it performs heating control of the preheated water HW and other operations through information processing, and supplies hot water hHW controlled to the set hot water supply temperature. When the commercial power supply 8 is out of power, the BB control unit 54 stops operating, so heating control of the preheated water HW is not performed. That is, if BB6 is a water heater independent of the FC unit 4, when the commercial power supply 8 is out of power, it only allows water supply from the FC unit 4 to pass through.

[0043] BB6 illustrated in FIG. 2 includes functional parts such as heat exchangers 56 and 58. The heat exchanger 56 is composed of, for example, a plate heat exchanger. During hot water supply, it receives preheated water HW from the FC unit 4 and performs heat exchange with the heat medium HM3. When the commercial power supply 8 is powered on, the amount of preheated water HW entering the heat exchanger 56 is detected by the water amount sensor 60 and controlled by the water control valve 62 controlled by the BB control unit 54.

[0044] Hot water hHW, which is preheated water HW after heating in heat exchanger 56, flows into hot water outlet path 64. The temperature of this hot water hHW is detected by temperature sensor 66 and reaches mixing valve 68. A bypass path 70 is connected to this mixing valve 68, and this bypass path 70 is connected to the inlet side of heat exchanger 56. Preheated water HW (=HW1 or HW2) before heating flows into this bypass path 70 depending on the opening degree of mixing valve 68, and this preheated water HW and hot water hHW are mixed, and the temperature of the hot water hHW is controlled to the set hot water outlet temperature. The temperature of the hot water hHW after mixing with the preheated water HW is detected by temperature sensor 72. This detected temperature is provided to BB control unit 54 and used to control to the set hot water outlet temperature Tm. That is, the mixing section 69 for controlling the temperature to the set outlet hot water temperature Tm includes, as an example, the water volume sensor 60, the water control valve 62, the mixing valve 68 and the bypass passage .

[0045] A heat medium HM3 for heating the preheated water HW circulates through the heat exchanger 56 installed in the hot water outlet path 64 and the circulation path 74 during power supply from the commercial power source 8. The heat exchanger 56, the heat exchanger 58, the heat medium tank 76, the circulation pump 78, and the temperature sensor 80 are installed in this circulation path 74. During hot water supply, the BB control unit 54 operates the circulation pump 78 based on the water volume detection by the water volume sensor 60 and starts combustion in the burner 82. The heat exchanger 58 exchanges heat between the heat of the combustion exhaust of the fuel gas G generated in the burner 82 and the heat medium HM3. Then, the BB control unit 54 controls the combustion of the burner 82 based on the temperature detected by the temperature sensor 80.

[0046] When the commercial power supply 8 experiences a power outage, the BB control unit 54 stops operating, and therefore, as shown in FIG. 3, the BB 6 does not have the function of controlling hot water supply. However, as one of the functions of the BB 6, it passes preheated water HW (= HW1 or HW2) from the FC unit 4 through the BB 6.

[0047] When the commercial power supply 8 is interrupted, the bypass passage 70 side of the mixing valve 68 of the BB 6 may be reset to a fully open state to allow the preheated water HW to flow through the bypass passage 70 side. This makes it possible to reduce pressure loss caused by the heat exchanger 56.

[0048] <Hardware of the control unit 12 and the remote control unit 22> FIG. 4 shows the hardware of the control unit 12 and the remote control unit 22.

[0049] Control unit 12 is formed, for example, by a computer with a communication function, and includes a processor 84, a storage unit 86, an input / output unit (I / O) 88, and a communication unit 90. Processor 84 executes an OS (Operating System) stored in storage unit 86, a control program including hot water supply control, and the like.

[0050] The storage unit 86 is an example of a recording medium for recording the programs of the present disclosure and control information used by the control unit 12. The storage unit 86 includes memory elements such as a read-only memory (ROM) and a random-access memory (RAM). The ROM stores an OS, a hot water supply control program, control information, data for various controls, and the like. The RAM constitutes a work area for information processing.

[0051] Under the control of the processor 84, the I / O 88 acquires detection information from the temperature sensors 28, 34, 40, 48, 52, the water volume sensor 42, etc., and outputs control signals for controlling the drive of the circulation pump 26 and the valve opening of the distribution valve 44 and the water control valve 50. Under the control of the processor 84, the communication unit 90 communicates with the remote control unit 22 and transmits and receives control information and presentation information.

[0052] The remote control unit 22 includes a remote control control unit 92, an input operation unit 94, a communication unit 96, and an LCD (Liquid Crystal Display) display unit 98. The remote control control unit 92 includes a processor, a storage unit, an input / output unit, and the like, similar to the control unit 12, and communicates with the control unit 12 when the commercial power source 8 is supplying power or when there is a power outage. At this time, the communication unit 96 communicates with the communication unit 90 of the control unit 12 under the control of the remote control control unit 92, and transmits and receives control information and presentation information.

[0053] The input operation unit 94 is used for inputting information such as the temperature setting of the preheating water HW under the control of the remote control unit 92. The input operation unit 94 may be a touch sensor that covers the screen of the LCD display unit 98.

[0054] The LCD display unit 98 is an example of an information presentation unit in the present disclosure, and is used to present information such as mode information, temperature information of the preheating water HW, and operating status information.

[0055] <Control function of control unit 12> 5 shows an example of the control functions of the control unit 12. The control functions include temperature setting 100, power supply monitoring 102, power generation monitoring 104, power generation maintenance 105, temperature change 106, hot water supply control 108, presentation information generation 110, and the like.

[0056] Temperature setting 100: This temperature setting 100 includes the initial setting and change setting of the preheating water HW. When the commercial power source 8 is supplied, the hot water outlet temperature is controlled by the BB6, so the set temperature Tc of the preheating water HW is set to a value Tc1 ( <Tm)でよい。このTc1はたとえば、15~30〔℃〕でよい。

[0057] In contrast, when the commercial power supply 8 is interrupted, the outlet hot water temperature is not increased by the BB6, and hot water is supplied using the preheated water HW generated by the FC unit 4, so the set temperature Tc of this preheated water HW is set to a value Tc2 (>Tc1) higher than the value Tc1. As described above, this Tc2 may be set to, for example, 40°C or higher, but it may also be a value equivalent to the set outlet hot water temperature Tm.

[0058] Power supply monitor 102: This power supply monitor 102 monitors whether the commercial power source 8 is supplying power or is experiencing a power outage. This monitoring includes a power supply determination of the commercial power source 8. This power supply determination may be made by determining whether power is being supplied or there is a power outage based on, for example, detection of the frequency (50 [Hz] or 60 [Hz]) of the commercial power source 8, detection of periodic waveform changes in the AC voltage, or the like.

[0059] Based on this power supply monitoring 102, the control unit 12 determines that the commercial power source 8 has transitioned from power supply to a power outage, and based on this determination result, executes operations such as continuing power generation by the power generation unit 14 and changing the set temperature Tc of the preheating water HW.

[0060] Power generation monitoring 104: In this power generation monitoring 104, the control unit 12 monitors the power generation of the power generation unit 14 based on the power generated by the power generation unit 14, regardless of whether the commercial power source 8 is being supplied or there is a power outage.

[0061] Power generation maintenance 105: When the commercial power source 8 fails while the power generation unit 14 is generating electricity, this power generation maintenance 105 maintains power generation by the power generation unit 14 under the control of the control unit 12. In other words, even if the commercial power source 8 fails, general power supply is ensured by the power generated by the power generation unit 14 and the operation of the FC unit 4 is continued.

[0062] Temperature change 106: This temperature change 106 includes the initial setting of the preheated water HW and a change thereto. When the commercial power source 8 is interrupted during power generation by the power generation unit 14, the control unit 12 controls the power generation unit 14 to transition to a temperature change mode, and the set temperature Tc is changed from a value Tc1 before the interruption of the commercial power source 8 to a value Tc2 after the interruption.

[0063] Hot water supply control 108: In addition to temperature control of the preheated water HW, this hot water supply control 108 may also include operation control of the BB6 independent of the FC unit 4, separate from the control of the FC unit 4. According to such control, when the commercial power supply 8 experiences a power outage, the operation of the BB6 is stopped by control of the control unit 12, and the hot water supply control of the BB6 is released, thereby making it possible to suppress wasteful consumption of power generated by the power generation unit 14, for example, that would otherwise be caused by continued operation of the BB6.

[0064] Furthermore, when the set temperature Tc is changed from Tc1 to Tc2 in the temperature change mode, the control unit 12 controls the temperature of the preheated water HW to the set temperature Tc=Tc2 with Tc2 as the target value. Therefore, hot water hHW controlled to this temperature is dispensed from the BB6.

[0065] Presentation information generation 110: This presentation information generation 110 includes the generation of temperature information indicating the set temperature Tc of the preheating water HW and the outlet hot water temperature. This temperature information is provided from the control unit 12 to the remote control unit 22 and displayed on the LCD display unit 98.

[0066] <Preheat water HW temperature setting> Fig. 6 shows a processing procedure for controlling the temperature of the preheated water HW. This processing procedure is an example of the hot water supply method of the present disclosure, and includes a process for controlling the supply of hot water of the preheated water HW. In Fig. 6, S indicates a process unit, and the numbers attached to S indicate an example of the order of the processes.

[0067] This processing procedure includes selecting and setting the preheated water temperature (S101, S102), determining whether there is a power outage (S103), stopping the operation of BB6 (S104), determining whether power is being generated (S105), continuing power generation (S106), confirming changes to the set temperature Tc of the preheated water HW (S107), changing or maintaining the set temperature Tc (S108, S109), and other steps such as heat storage control to store the heat medium HM2 in the heat storage tank 18, and exchanging the heat of the heat medium HM2 with the supply water W to generate preheated water HW.

[0068] At the time of initial setting, a selection is made in advance as to whether or not to set the temperature of the preheated water HW to be dispensed (S101). If the temperature setting of the preheated water HW is selected (YES in S101), the temperature of the preheated water HW to be dispensed is set (S102). This setting is performed by the remote control unit 22, and the set temperature Tc is stored in the memory unit 86 together with information indicating that it has been set. If the temperature setting of the preheated water HW is not selected (NO in S101), the process of S102 is skipped and the process proceeds to S103.

[0069] During operation of the hot water supply system 2, the control unit 12 monitors the commercial power source 8 and determines whether it is power supply or a power outage (S103). When the commercial power source 8 experiences a power outage, the operation of the BB6 is stopped (S104). In this case, the operation of the BB6 can be automatically stopped when power is being supplied from the commercial power source 8, but even when the BB6 is being operated using power generated by the power generation unit 14, the power supply to the BB6 is cut off, the operation of the BB6 is stopped, and power consumption by the BB6 is prevented.

[0070] When commercial power supply 8 experiences a power outage, control unit 12 monitors the operation of power generation unit 14 and determines whether power generation is in progress (S105).

[0071] When the commercial power source 8 fails, if the power generation unit 14 is generating power (YES in S105), the control unit 12 causes the power generation unit 14 to continue generating power (S106). Although the BB6 stops when the commercial power source 8 fails, the FC unit 4 continues to operate by receiving the generated power as the power generation unit 14 continues to generate power.

[0072] At this time, the control unit 12 determines whether the set temperature Tc of the preheating water HW has been changed (S107). If there is a change (YES in S107), the set value of the set temperature Tc is changed to a value Tc2 that is higher than the value Tc1 before the power outage of the commercial power source 8 (S108). If there is no change (NO in S107), the set value of the set temperature Tc is maintained at the value Tc1 before the power outage of the commercial power source 8 (S109).

[0073] As a result, the control unit 12 controls the preheated water HW to the set temperature Tc=Tc1 or Tc2, and dispenses hot water hHW controlled to Tc2 or preheated water HW controlled to Tc1.

[0074] <Changes in hot water temperature during a power outage on commercial power supply 8> FIG. 7 shows the changes in the set temperature Tc of the preheated water HW, the set outlet hot water temperature Tm, and the outlet hot water temperature Thw of the preheated water HW.

[0075] When power is supplied from the commercial power source 8, the preheated water HW1, which has been set to a value Tc1 related to the initial setting of the set temperature Tc, is controlled to a temperature Thw1. At this time, this preheated water HW1 is supplied from the FC unit 4 to the BB6, which controls it to the set hot water outlet temperature Tm, causing hot water to be discharged at a temperature higher than Tc1.

[0076] In contrast, if the commercial power supply 8 experiences a power outage at time tx, BB6 stops operating and the backup function is lost. At this time, the FC unit 4 uses the power outage as a trigger to maintain the set temperature Tc of the preheated water HW1 at Tc1 or change it from Tc1 to Tc2. If a change in the set temperature Tc is required, the control unit 12 raises the set temperature Tc of the preheated water HW1 to Tc2. Therefore, the preheated water HW2 is controlled to Tc2, heated to Thw2, and dispensed from BB6.

[0077] <Advantages of the First Embodiment> According to this configuration, any one of the following effects can be obtained. (1) When the commercial power supply 8 experiences a power outage, the operation of the BB 6 can be stopped to reduce the power consumption of the BB 6, and hot water at the desired temperature can be supplied using the preheated water HW generated by the FC unit 4.

[0078] (2) If the power generation unit 14 is generating electricity, when the commercial power source 8 experiences a power outage, the power generation unit 14 can continue to generate electricity and the temperature of the preheated water HW can be raised on the FC unit 4 side, thereby providing hot water at the same level as before the commercial power source 8 was interrupted.

[0079] (3) The exhaust heat generated by the power generation unit 14 can be exchanged with the heat medium HM2 and stored in the heat storage tank 18, so that even during a power outage of the commercial power source 8, the heat energy stored in the heat storage tank 18 can be effectively utilized.

[0080] (4) Even if the heat storage tank 18, which stores the exhaust heat from the power generation of the power generation unit 14 in the heat medium HM2, becomes full, the heat storage tank 18 can be restored to its full state by heating the preheated water HW and using it for hot water supply without any special processing such as dissipating heat from the heat medium HM2.

[0081] Second Embodiment The first embodiment includes a process for changing the value Tc1 relating to the initial setting of the set temperature Tc to a value Tc2 when the commercial power source 8 is interrupted. The value Tc2 of the set temperature Tc may be either a fixed value or a variable value, and if it is a variable value, a desired hot water supply temperature can be realized.

[0082] Fig. 8 shows a process procedure for controlling the temperature of preheated water HW in a hot water supply system 2 according to the second embodiment. In Fig. 8, S denotes a process unit, and the numbers attached to S denote an example of the order of the processes.

[0083] This processing procedure includes initial setting of the preheated water temperature (S201), power outage determination (S202), stopping operation of BB6 (S203), power generation determination (S204), continuing power generation (S205), determining whether to adjust the set temperature Tc of the preheated water HW (S206), changing or maintaining the set temperature Tc (S207, S208), and other processes such as heat storage control to store the heat medium HM2 in the heat storage tank 18, and exchanging the heat of the heat medium HM2 with the supply water W to generate preheated water HW.

[0084] At the time of initial setting, the set temperature Tc of the preheated water HW to be discharged is set in advance to Tc1 as an initial value (S201).

[0085] During operation of the hot water supply system 2, the control unit 12 monitors the commercial power source 8 and determines whether there is power supply or a power outage (S202). When the commercial power source 8 experiences a power outage, the operation of the BB6 is stopped (S203). In this case, when power is being supplied from the commercial power source 8, the operation of the BB6 can be automatically stopped, but when the BB6 is being operated using power generated by the power generation unit 14, even in this embodiment, the power supply to the BB6 is cut off and the operation of the BB6 is stopped, thereby preventing power consumption by the BB6.

[0086] When the commercial power source 8 experiences a power outage, the control unit 12 monitors the operation of the power generation unit 14 and determines whether or not power generation is in progress (S204).

[0087] When the commercial power source 8 fails, if the power generation unit 14 is generating electricity (YES in S204), the control unit 12 causes the power generation unit 14 to continue generating electricity (S205). Although the BB6 stops when the commercial power source 8 fails, the FC unit 4 continues to operate by receiving the generated electricity as the power generation unit 14 continues to generate electricity.

[0088] At this time, the control unit 12 determines whether the set temperature Tc of the preheating water HW has been adjusted or changed (S206). If there has been an adjustment change (YES in S206), the set value of the set temperature Tc is changed to one of values ​​Tc2-1, Tc2-2, . . . , Tc2-n, which is higher than Tc1, which is the initial value before the power outage of the commercial power source 8 (S207). If there has been no change in the set temperature Tc (NO in S206), the set value of the set temperature Tc is maintained at Tc1, which is the initial value before the power outage of the commercial power source 8 (S208).

[0089] As a result, the control unit 12 controls the preheated water HW to the set temperature Tc=Tc1, or Tc2-1, Tc2-2, . . . , Tc2-n, and dispenses the preheated water HW1 or preheated water HW2.

[0090] <Changes in hot water temperature during a power outage on commercial power supply 8> 9 shows the transitions of the set temperature Tc of the preheated water HW, the set outlet hot water temperature Tm, and the outlet hot water temperature Thw of the preheated water HW. In FIG. 9, the same reference numerals are used for the same parts as in FIG.

[0091] When power is supplied from commercial power source 8, preheated water HW1, which has been set to value Tc1 related to the initial setting of set temperature Tc, is controlled to temperature Thw1, as in the first embodiment. At this time, this preheated water HW1 is supplied from FC unit 4 to BB6, which controls it to set hot water outlet temperature Tm, causing hot water to be discharged at a temperature higher than Tc1.

[0092] In contrast, if the commercial power supply 8 fails at time tx, the BB6 stops operating and the backup function is lost. At this time, the FC unit 4 uses the failure as a trigger to maintain the set temperature Tc of the preheating water HW1 at Tc1 or adjust it to Tc2-1, Tc2-2, ..., Tc2-n. This adjustment can be performed by the remote control unit 22.

[0093] When the set temperature Tc is changed to any of the values ​​Tc2-1, Tc2-2, ..., Tc2-n, the control unit 12 increases the set temperature Tc of the preheated water HW1. Therefore, the preheated water HW2 is controlled to, for example, Tc2-n, at which the set temperature Tc has been changed, and the preheated water HW2 heated to Thw2 using this Tc2-n is dispensed.

[0094] <Advantages of the Second Embodiment> According to this configuration, any one of the following effects can be obtained. (1) In the second embodiment, the same effects as in the first embodiment can be obtained.

[0095] (2) When a power outage occurs in the commercial power supply 8, the set temperature Tc of the preheated water HW can be changed to any value, and the preheated water HW can be discharged at a temperature equivalent to the set outlet temperature Tm.

[0096] (3) Since the operation of the BB 6 is stopped to maintain the generated power of the power generation unit 14, power consumption within the system can be reduced and the availability of generated power can be increased during a power outage of the commercial power source 8. EXAMPLES

[0097] This embodiment is an example in which the set temperature Tc of the preheated water HW can be changed by adjusting the valve opening θ of the distribution valve 44.

[0098] FIG. 10 shows mixing control using the distribution valve 44, where A shows the state of the valve opening degree θ1, and B shows the state of the valve opening degree θ2.

[0099] The distributor valve 44 is provided with a valve body 116 in a chamber 114 of a valve body 112. Ports 118-1, 118-2, and 118-3 are formed in the chamber 114. The feed water W flows from the port 118-1 on the feed water passage 36 side into the chamber 114, and from this chamber 114, feed water W1 diverted from the feed water W flows into port 118-2 on the inlet side of the heat exchanger 20, and feed water W2 diverted from the feed water W flows into port 118-3 on the bypass passage 46 side.

[0100] The valve element 116 is rotatable about a central axis O within the chamber 114. This valve element 116 rotates by receiving a rotational force from a stepping motor 120, and is controlled to valve openings θ1 and θ2. A driving output is applied to the stepping motor 120 from a valve driving unit 122, and this driving output is controlled by the control unit 12 described above. This control includes control of the setting of the valve openings θ1 and θ2, the transition time from the valve opening θ1 to the valve opening θ2, the transition time from the valve opening θ2 to the valve opening θ1, and the like.

[0101] <Effects of the embodiment> According to this embodiment, any one of the following effects can be obtained. (1) As shown in A of FIG. 10, when the valve opening degree θ1 (<θ2) of the valve element 116 of the distribution valve 44 is set, most of the feedwater W1 can be supplied to the heat exchanger 20.

[0102] (2) In contrast to this, as shown in FIG. 10B, when the valve opening degree θ2 of the valve element 116 of the distribution valve 44 is set, the supply water W2 flowing into the bypass passage 46 can be increased.

[0103] (3) Therefore, the set temperature Tc of the preheated water HW can be changed to a desired value by changing the valve opening degree θ.

[0104] Other Embodiments The present disclosure includes the following embodiments. (1) In the above embodiment, the FC unit 4 is configured to include the power adjustment unit 10 and the FC unit control unit 12. However, for example, the control unit 12 may be configured as a control unit for the FC unit 4 independent of the FC unit 4, or a control unit may be configured that is integrated with any or all of the power adjustment unit 10, the FC unit control unit 12, and the remote control unit 22.

[0105] (2) The FC unit 4, which is an example of a first heat source device, uses exhaust heat from an SOFC as a heat source. However, an exhaust heat source other than an SOFC may be used as the heat source.

[0106] (3) The heat source installed in BB6 is the heat from fuel gas combustion, but other heat sources such as heat from liquid fuel combustion or electric heat may also be used.

[0107] (4) The heat exchanger 16 may be installed outside the power generation section 14, but may be installed inside the power generation section 14 so that the power generation section 14 has a heat exchange function for exchanging heat between the exhaust gas HM1 and the heat medium HM2.

[0108] (5) In the above embodiment, when a power outage occurs in the commercial power source 8, the control unit 12 continues power generation by the power generation unit 14. However, the configuration may be such that the remote control unit 22 instructs the control unit 12 to continue power generation.

[0109] (6) The hot water supply system 2 disclosed herein describes a case in which the control unit 12 does not perform system control of the FC unit 4 and BB6. However, this also includes a case in which the BB6 is controlled independently of the FC unit 4, even if coordinated control between the FC unit 4 and BB6 is not performed.

[0110] As described above, the most preferred embodiment of the present invention has been described. The present invention is not limited to the above description. Various modifications and changes are possible for those skilled in the art based on the gist of the invention described in the claims or disclosed in the description for carrying out the invention. It goes without saying that such modifications and changes are included in the scope of the present invention. [Industrial Applicability]

[0111] According to the present disclosure, when an AC power outage occurs, the operation of the second heat source unit is stopped while the power generation unit continues to generate electricity, thereby limiting power consumption within the system to only driving the first heat source unit, thereby reducing consumption, and the temperature of the preheated water can be raised to provide hot water equivalent to that before the power outage, thereby realizing a highly convenient hot water supply system. [Explanation of symbols]

[0112] 2. Hot water system 4 FC unit 6 Backup heat source unit (BB) 8 Commercial power supply 10 Power adjustment section 12 FC unit control section 14 Power Generation Division 16, 20, 56, 58 heat exchanger 18 Heat storage tank 22 Remote control unit 24, 30, 74 circulation path 26, 32, 78 Circulation pump 28, 34, 40, 48, 52, 66, 72, 80 Temperature Sensor 36 Water supply channel 38, 64 Hot water outlet 42, 60 Water level sensor 44 Distribution valve 45, 69 Mixing section 46, 70 Bypass 50, 62 Water control valve 54 Backup heat source unit control section 68 Mixing valve 76 Heat Transfer Tank 82 Burner 84 processors 86 Memory section 88 Input / output section (I / O) 90, 96 Communications Department 92 Remote control unit 94 Input operation section 98 LCD display section 100 temperature settings 102 Power supply monitoring 104 Power Generation Monitoring 105 Maintaining Power Generation 106 Temperature Change 108 Hot water control 110 Presentation information generation 112 Valve body 114 Chamber 116 Valve body 118-1, 118-2, 118-3 ports 120 Stepping motor 122 Valve drive unit HW Preheated water HM2 heat medium Tm Set outlet temperature Tc set temperature Thw Outlet temperature

Claims

1. A hot water supply method including at least a first heat source unit and a second heat source unit, supplying preheated water from the first heat source unit to the second heat source unit, and supplying hot water from the second heat source unit, a step of exchanging exhaust heat from the power generation section with a heat medium and storing the heat medium in a heat storage tank; a step of exchanging heat of the heat medium in the heat storage tank with feed water to generate the preheated water; a step of: when the AC power source is supplying power during power generation of the power generation unit, supplying hot water from the second heat source unit which has received the preheated water from the first heat source unit either hot water which has passed through the heat exchanger or the preheated water which has passed through the bypass passage, or hot water which is a mixture of the hot water and the preheated water, according to an opening degree of a mixing valve which changes an inflow ratio between the heat exchanger of the second heat source unit and a bypass passage which bypasses the heat exchanger; when the AC power source is interrupted, stopping the supply of power to the second heat source unit, continuing the power generation of the power generation unit, and supplying the preheated water from the first heat source unit to the second heat source unit, changing a set temperature of the preheated water to a value higher than the value before the AC power source is interrupted, controlling the temperature of the preheated water to the set temperature, and flowing all of the preheated water supplied to the second heat source unit into the bypass passage to supply hot water from the second heat source unit; A hot water supply method comprising:

2. A hot water supply system including at least a first heat source unit and a second heat source unit, supplying preheated water from the first heat source unit to the second heat source unit, and supplying hot water from the second heat source unit, The first heat source unit, A power generation section; a first heat exchange unit that exchanges heat between a heat medium and exhaust heat generated by power generation of the power generation unit; A heat storage tank for storing the heat medium; a second heat exchange unit that exchanges heat between the heat of the heat medium supplied from the heat storage tank and the supply water to generate the preheated water; The second heat source unit, A heat exchanger that heats the preheated water supplied from the first heat source unit; a bypass passage that bypasses the heat exchanger; a mixing valve connected to the heat exchanger and the bypass passage and changing an inflow ratio of the preheated water into the heat exchanger and the bypass passage according to an opening degree of the mixing valve; a control unit that, when power is supplied from an AC power source, supplies hot water from the second heat source unit which has received the preheated water from the first heat source unit, either hot water which has passed through the heat exchanger or the preheated water which has passed through the bypass path, or hot water which is a mixture of the hot water and the preheated water, depending on the opening degree of the mixing valve, and when the AC power source is interrupted, stops supplying power to the second heat source unit, continues power generation of the power generation unit, and supplies the preheated water from the first heat source unit to the second heat source unit, changes the set temperature of the preheated water to a value higher than the value before the AC power source is interrupted, controls the temperature of the preheated water to the set temperature, and flows all of the preheated water supplied to the second heat source unit into the bypass path to supply hot water from the second heat source unit; , including a hot water system.

3. The hot water supply system according to claim 2 , wherein the power generation unit includes a heat exchange function for exchanging heat between the exhaust heat and the heat medium.

4. a power generation monitoring unit that monitors power generation by the power generation unit; a power supply monitoring unit that monitors the power supply of the AC power source; 4. The hot water supply system according to claim 2, wherein when the AC power supply is interrupted while the power generation unit is generating electricity, the control unit causes the power generation unit to continue generating electricity.

5. A relay having a function of instructing the control unit to continue power generation of the power generation unit when the AC power supply is interrupted. The hot water supply system according to any one of claims 2 to 4, further comprising a remote control unit.

6. The preheating water temperature setting function is provided, and the preheating water temperature setting function is provided to set the preheating water temperature setting function to the preheating water temperature setting function when the AC power supply is interrupted. The present invention relates to a method for controlling a control unit, and more particularly to a method for controlling a control unit. Hot water system.

7. A program executed by a computer, The system includes at least a first heat source device and a second heat source device, and has a function of supplying preheated water from the first heat source device to the second heat source device; a function of controlling the opening degree of a mixing valve that changes the inflow ratio between the heat exchanger of the second heat source unit and a bypass passage that bypasses the heat exchanger when an AC power source is supplying power, and supplying hot water from the second heat source unit that receives the preheated water from the first heat source unit either hot water that has passed through the heat exchanger or the preheated water that has passed through the bypass passage, or hot water that is a mixture of the hot water and the preheated water; a function of stopping the supply of power to the second heat source unit when the AC power source is interrupted during power generation by the power generation unit, continuing power generation by the power generation unit, and supplying the preheated water from the first heat source unit to the second heat source unit, and changing the set temperature of the preheated water to a value higher than the value before the power failure of the AC power source; A function of controlling the temperature of the preheated water to the changed set temperature and flowing all of the preheated water supplied to the second heat source device into the bypass passage to supply hot water from the second heat source device; A program for causing the computer to execute the above.

8. A recording medium storing control information used in the control unit of the hot water supply system according to any one of claims 2 to 6, or storing the program according to claim 7.

9. A control unit comprising either a control unit included in the hot water supply system according to any one of claims 2 to 6 or a control unit included in the remote control unit according to claim 6.

Images