JP2007147108A - Hot-water storage type hot-water supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a hot-water storage type hot-water supply device capable of preventing abnormal stoppage of a heat pump unit, and improving controllability of a flow rate. <P>SOLUTION: The hot-water storage type hot-water supply device is provided with a hot water storage tank 310, the heat pump unit 200 leading hot supply water in the hot water storage tank 310 to a water heat exchanger 220 carrying out heat exchange between a coolant and the hot supply water 1 to carry out heating operation, an electric pump 330 passing the hot supply water taken out from a lower part of the hot water storage tank 310 through the water heat exchanger 220 and pumping it to an upper part of the hot water storage tank 310, and a heat source controller 270 controlling a rotational frequency of the electric pump 330 such that a heating temperature of the hot supply water flowing out from the water heat exchanger 220 becomes a target heating temperature. The heat source controller 270 has a correcting means 170 for correcting an indicator voltage in response to an actual rotational frequency by determining a target rotational frequency providing the target heating temperature based upon of an actual heating temperature, and a voltage output value providing the target rotational frequency, and outputting the voltage output value to the electric pump 330. By this, the controllability of the flow rate becomes favorable. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a hot water storage hot water supply apparatus including a hot water storage tank for storing a hot water supply fluid, and a heat pump unit that performs a boiling operation by exchanging heat between the hot water supply fluid and the refrigerant in the hot water storage tank. The present invention relates to control of an electric pump that is operated when a unit performs a boiling operation.

  Conventionally, as this type of hot water supply apparatus, for example, as shown in Patent Document 1, a hot water supply fluid is heated and heated using a supercritical heat pump cycle in which the refrigerant pressure on the high pressure side is increased to a critical pressure or higher. 2. Description of the Related Art A heat pump type hot water supply device that operates is known.

  In this hot water supply apparatus, a water heat exchanger that is a radiator for exchanging heat between the hot water supply fluid and the refrigerant is provided, and the hot water supply fluid heated by the water heat exchanger is stored in a hot water storage tank, This hot water supply system supplies hot water supply fluid to a user after taking out a hot water supply fluid from the hot water storage tank and adjusting the temperature.

And the hot water storage tank and the fluid flow path of a water heat exchanger are connected, and the circulating water path which interposed the electric pump in the middle of the connection is formed. The electric pump adjusts the flow rate by controlling the rotational speed so that the actual boiling temperature of the hot water supply fluid flowing out from the water heat exchanger becomes the target boiling temperature.
JP 2002-206805 A

  In Patent Document 1, a more specific control method for controlling the rotation speed of the electric pump is not described. However, in this type of variable electric pump, a voltage output value corresponding to the target rotation speed is obtained, and the voltage By outputting the output value to the electric pump, the flow rate is adjusted by changing the rotation speed of the electric pump.

  However, in this type of electric pump, there is a problem that the actual rotational speed varies with respect to the target rotational speed due to the variation of the motor itself by changing the rotational speed via the voltage output value. That is, there is a problem that a deviation occurs in the actual rotational speed even if the voltage output value provides the target rotational speed. As a result, the rise characteristic deteriorates even though the actual boiling temperature becomes the target boiling temperature.

  Further, for example, when the actual boiling temperature is lower than the target boiling temperature when the boiling operation is started, if the actual boiling temperature is lower than the target boiling temperature, the control is output to the electric pump to increase the actual boiling temperature. The value is output with the lowest voltage output value. However, even in this case, when the rotational speed fluctuates due to the variation of the single motor and the actual flow rate becomes a predetermined flow rate (for example, 0 L / min) or less, the heat pump unit is caused by boiling in the heat pump cycle, abnormal increase in high pressure, etc. Problems such as abnormal stoppage and deterioration of durability occur.

  In view of the above, an object of the present invention is to provide a hot water storage type hot water supply apparatus that can prevent abnormal stop of a heat pump unit and that has good flow rate controllability.

In order to achieve the above object, the technical means according to claims 1 to 5 are employed. That is, according to the first aspect of the present invention, the hot water storage tank (310) for storing the hot water supply fluid and the heat pump cycle exchange heat between the refrigerant discharged from the compressor (210) and the hot water supply fluid, and the refrigerant flow. Pump unit having a radiator (220) configured to oppose a hot water supply fluid flow and conducting a boiling operation by introducing the hot water supply fluid in the hot water storage tank (310) to the radiator (220) (200), a hot water supply fluid taken out from the lower part of the hot water storage tank (310) is passed through the radiator (220) and pumped to the upper part of the hot water storage tank (310), and a radiator ( 220) control means (270) for controlling the number of revolutions of the electric pump (330) so that the boiling temperature of the hot water supply fluid flowing out from the hot water supply fluid becomes the target boiling temperature,
Based on the boiling temperature, the control means (270) obtains the target rotational speed at which the target boiling temperature is obtained and the instruction voltage for obtaining the target rotational speed, and outputs the instruction voltage to the electric pump (330). It has a correction means (170) for correcting the command voltage according to the number of rotations.

  According to the present invention, the electric pump (330) that changes the rotation speed via the command voltage generally has a problem that the actual rotation speed varies with respect to the target rotation speed due to variations in the motor itself. Therefore, in the present invention, the correction means (170) for correcting the command voltage according to the actual rotational speed is provided, so that it is possible to converge to an accurate target rotational speed by absorbing the variation of the single motor. Thereby, the controllability of the flow rate of the electric pump (330) is improved.

  The invention according to claim 2 is characterized in that the correction means (170) compares the actual rotational speed with the target rotational speed to obtain a deviation, and corrects the command voltage based on the deviation. More specifically, according to the present invention, it is possible to reliably absorb variations in a single motor by correcting the command voltage based on the deviation.

  In the invention according to claim 3, the electric pump (330) is set with a lower limit flow rate of the hot water supply fluid flowing out of the radiator (220), and the control means (270) is configured such that the command voltage has the lower limit flow rate. It is characterized in that it is determined based on the number of revolutions that does not fall below. According to the present invention, when raising the boiling temperature, the lowest command voltage does not fall below the lower limit flow rate, so that the heat pump unit (200) is abnormally stopped due to boiling in the heat pump cycle, abnormal increase in high pressure, etc. Can be prevented.

  In the invention according to claim 4, the control means (270) controls the rotational speed of the electric pump (330) by fixing the command voltage when the command voltage is at a rotational speed that does not fall below the lower limit flow rate. It is characterized by that. According to the present invention, the present invention can be applied to the freeze prevention operation of the circulating water circuit of the electric pump (330) and the air vent operation of the circulating water circuit. In this case, power saving and noise reduction can be obtained by operating at the minimum rotational speed.

  The invention according to claim 5 is characterized in that the heat pump unit (200) includes a supercritical heat pump cycle in which the refrigerant pressure on the high temperature side is equal to or higher than the critical pressure of the refrigerant. According to the present invention, a hot water supply fluid having a high temperature (for example, about 85 ° C.) can be stored in the hot water storage tank (310).

  In addition, the code | symbol in the bracket | parenthesis of each said means shows a corresponding relationship with the specific means of embodiment mentioned later.

  Hereinafter, a hot water storage type hot water supply apparatus according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram showing the overall configuration of the hot water storage type hot water supply apparatus of the present embodiment, and FIG. 2 is an electric block diagram of a heat source control apparatus 270 that controls the electric pump 330.

  FIG. 3 is a flowchart showing a control process of the heat source control device 270. FIG. 4 is an explanatory diagram showing a specific example in which the voltage output value is corrected according to the deviation in the correction means 170. FIG. 5 is a characteristic diagram showing the relationship between the voltage output value of the electric pump 330 and the rotational speed, and FIG. 6 is a characteristic diagram showing the relationship between the flow rate of the electric pump 330 and the rotational speed.

  Incidentally, in FIG. 1, a heat pump unit 200 uses an electric expansion valve 230 as a pressure reducer, and heats hot water as a hot water supply fluid to generate hot water of high temperature (about 85 ° C. in this embodiment). Cycle.

  This supercritical heat pump cycle refers to a heat pump cycle in which the refrigerant pressure on the high pressure side is equal to or higher than the critical pressure of the refrigerant. For example, the heat pump cycle uses carbon dioxide, ethylene, ethane, nitrogen oxide, or the like as a refrigerant.

  As shown in FIG. 1, the hot water storage type hot water supply apparatus of the present embodiment includes a hot water storage tank 310 that stores hot water and a heat pump cycle, and guides the hot water in the hot water storage tank 310 to a water heat exchanger 220 that is a radiator. A heat pump unit 200 that performs a boiling operation, a circulating water circuit 320 for passing hot water in a hot water storage tank through the water heat exchanger 220, and a heat source control device 270 that is a control means are configured.

  As shown in FIG. 1, the heat pump unit 200 is a compressor 210 for sucking and compressing refrigerant (carbon dioxide in the present embodiment), and the compressor 210 is a compression mechanism (not shown) for sucking and compressing refrigerant. And an electric compressor (not shown) that drives the compression mechanism.

  Reference numeral 220 denotes a water heat exchanger that is a heat exchanger that exchanges heat between the refrigerant discharged from the compressor 210 and hot water. The water heat exchanger 220 is configured such that the refrigerant flow and the hot water flow are opposed to each other. The counterflow type heat exchanger.

  230 is an electric expansion valve that is a pressure reducer that depressurizes the refrigerant flowing out of the water heat exchanger 220, and 240 is an evaporator that evaporates the refrigerant flowing out of the electric expansion valve 230 (hereinafter referred to as the expansion valve 230). This is an evaporator that absorbs heat in the atmosphere into the refrigerant and flows out the refrigerant toward an accumulator 250 (a suction side of the compressor 210) described later.

  Reference numeral 250 denotes an accumulator that separates the refrigerant flowing out of the evaporator 240 into a gas-phase refrigerant and a liquid-phase refrigerant, flows the gas-phase refrigerant to the suction side of the compressor 210, and stores excess refrigerant in the heat pump cycle.

  Reference numeral 260 denotes a blower that can blow air (outside air) to the evaporator 240 and adjust the amount of blown air. The blower 260, the compressor 210, and the expansion valve 230 are pressure information detected by each sensor described later. The heat source control device 270 controls the temperature information.

  Reference numeral 271 denotes a refrigerant temperature sensor that detects the temperature of the refrigerant flowing out of the water heat exchanger 220, and reference numeral 272 denotes a first hot water temperature sensor (first hot water) that detects the temperature of hot water flowing into the water heat exchanger 220. Temperature detecting means). Reference numeral 273 denotes a refrigerant pressure sensor that detects the pressure of the refrigerant flowing out of the water heat exchanger 220 (high-pressure side refrigerant pressure).

  Reference numeral 274 denotes a second hot water temperature sensor (second hot water temperature detection means) that detects the temperature of hot water flowing out of the water heat exchanger 220. And the detection signal of each sensor 271-274 is input into the heat source control apparatus 270 which is a control means.

  Here, the refrigerant pressure on the high pressure side refers to the pressure of the refrigerant existing in the refrigerant passage from the discharge side of the compressor 210 to the inflow side of the expansion valve 230, and the pressure is the discharge pressure (hydraulic heat) of the compressor 210. The internal pressure of the exchanger 220 is substantially equal.

  On the other hand, the low-pressure side refrigerant pressure refers to the pressure of the refrigerant existing in the refrigerant passage from the outflow side of the expansion valve 230 to the suction side of the compressor 210, and the pressure is the suction pressure (evaporator 240) of the compressor 210. Is approximately equal to the internal pressure. Note that the temperature of the hot water detected by the second hot water temperature sensor 274 is referred to as the actual boiling temperature in this embodiment.

  Next, the hot water storage tank 310 is made of metal (for example, made of stainless steel) having excellent corrosion resistance, is formed in a vertically long shape, and a heat insulating material (not shown) is disposed on the outer peripheral portion so that hot hot water is supplied for a long time. Can be kept warm.

  In addition, an inlet 310a is provided on the bottom surface, and a water supply pipe 311 for introducing tap water into the hot water storage tank 310 is connected to the inlet 310a. In addition, upstream of the water supply pipe 311 is connected to tap water via a pressure reducing check valve and an opening / closing valve (not shown), and tap water having a predetermined pressure is introduced.

  On the other hand, a lead-out port 310b is provided at the uppermost part of the hot water storage tank 310, and a hot water supply pipe 312 for leading hot water in the hot water storage tank 310 is connected to the lead-out port 310b. Further, a discharge pipe provided with a relief valve (not shown) is connected in the course of the hot water supply pipe 312. When the pressure in the hot water storage tank 310 rises to a predetermined pressure or higher, the hot water in the hot water storage tank 310 is connected. Is discharged to the outside so that the hot water storage tank 310 or the like is not damaged.

  Further, a hot water tap 313 is provided at the end of the hot water supply pipe 312. In addition, hot water mixing means (not shown) is connected in the course of the hot water supply pipe 312 so that hot hot water in the hot water storage tank 310 and tap water are mixed to obtain hot water at a predetermined temperature. Yes.

  Note that the hot water mixing means (not shown) is a temperature control valve that adjusts the hot water temperature discharged to the hot water tap 313, and the other is connected to tap water, and hot water and tap water flowing through the hot water pipe 312. The hot water supply at the set temperature is discharged to the hot water tap 313 by adjusting the opening area ratio.

  In addition, a plurality of hot water thermistors (not shown) for detecting the amount of hot water or the temperature of hot water are arranged on the outer wall surface of the hot water tank 310 at substantially equal intervals in the vertical direction (the height direction of the hot water tank 310). The temperature information at each water level in the hot water storage tank 310 is output to the heat source control device 370.

  Thus, the boundary position between the hot water heated above the hot water storage tank 310 and the low temperature hot water before boiling below the hot water storage tank 310 can be detected, and the hot water temperature of the hot water at each water level. Can be detected.

  The circulating water circuit 320 is connected so as to pass hot water from the lowermost part of the hot water storage tank 310 to the inflow side of the water heat exchanger 220, and hot water heated by the water heat exchanger 220 is connected to the hot water storage tank 310. It is connected in an annular shape so as to discharge water at the top.

  More specifically, the suction port 310 c formed at the bottom of the hot water storage tank 310 and the inflow side of the water heat exchanger 220 are connected, and the discharge port 310 d formed at the top of the hot water storage tank 310 and the water heat exchange. The outflow side of the vessel 220 is connected. An electric pump 330 is disposed between the suction port 310 c and the inflow side of the water heat exchanger 220. Thereby, low-temperature hot water is passed through the inflow side of the water heat exchanger 220, and hot water heated by the water heat exchanger 220 is discharged to the top of the hot water storage tank 310.

  The electric pump 330 of the present embodiment is formed of, for example, a DC brushless motor, and flows out of the water heat exchanger 220 by changing the rotation speed based on a voltage output value that is an instruction voltage from the heat source control device 270. The flow rate of hot water is adjusted.

  That is, the electric pump so as to adjust the flow rate flowing out of the water heat exchanger 220 so that the actual boiling temperature detected by the second hot water temperature sensor 274 input to the heat source control device 270 becomes the target boiling temperature. The number of rotations of 330 is controlled.

  More specifically, as shown in FIG. 2, the heat source control device 270 and the electric pump 330 are configured to output the instruction voltage means 270 a output from the heat source control device 270 to the electric pump 330, and the actual rotational speed of the electric pump 330. The rotational speed detection means 270b that outputs to the control device 270, the instruction voltage correction means 270c that outputs from the heat source control device 270 to the electric pump 330, and the power supply means 270d that supplies power to the electric pump 330 are electrically connected.

  Here, the instruction voltage means 270a is a signal of a voltage output value that is an instruction voltage when a target rotation speed obtained so as to become the target boiling temperature based on the actual boiling temperature is obtained, and is the target rotation Calculated based on the number. The rotation speed detection means 270b is the actual rotation speed of the electric pump 330 when a voltage output value that is an instruction voltage is output.

  The command voltage correction unit 270c is a corrected command voltage signal obtained by correcting the voltage output value that is a command voltage when the actual rotation speed obtained by the rotation speed detection unit 270b has a deviation from the target rotation speed. (Specific control will be described later).

  The heat source control device 270 is mainly composed of a microcomputer, and a built-in ROM (not shown) is provided with a preset control program, and temperature information, pressure information from each sensor 271 to 274, Actuators such as the compressor 210, the expansion valve 230, the blower 260, and the electric pump 330 are controlled based on operation information from an operation panel (not shown).

  By the way, in the heat pump cycle, in order to operate the heat pump cycle in a region where the cycle efficiency (COP) is high, the low pressure hot water flowing into the water heat exchanger 220 and the high pressure flowing out from the water heat exchanger 220 by the heat source control device 270. A target temperature difference ΔTo (for example, 10 ° C.) that is a temperature difference from the refrigerant is set, and based on the target temperature difference ΔTo, the opening of the expansion valve 230 is changed to control the refrigerant pressure on the high pressure side.

  Next, the operation of the hot water supply system according to this embodiment will be described. First, in the case of supplying hot hot water stored in the hot water storage tank 310, when the hot water tap 313 provided at the end of the hot water supply pipe 312 is opened, tap water is stored in the hot water supply pipe 311 in conjunction with this. Water is supplied into the tank 310.

  Thereby, hot hot water stored in the hot water storage tank 310 is pushed out to the tap water, and the pushed hot water is supplied from the hot water tap 313. At this time, the hot water supplied from the hot water tap 313 is adjusted to a set temperature by hot water mixing means (not shown) for mixing hot water with tap water from the water supply pipe 311 and hot water pushed out from the hot water supply pipe 312. Yes.

  Accordingly, the hot water supply tap water used for adjusting the temperature by the hot water mixing means is supplied into the hot water storage tank 310 from below the hot water storage tank 310. That is, when hot water is supplied by opening the hot water tap 313, tap water is sequentially supplied from below the hot water storage tank 310, and the boundary position between the tap water and the hot water is moved upward.

  Then, when it is determined by a detection signal of a hot water storage thermistor (not shown) that the hot water temperature in the hot water storage tank 310 has become a predetermined temperature or lower, or it is determined that hot water having a predetermined temperature or lower has exceeded a predetermined amount. In such a case, a heating operation for boiling hot water in the hot water storage tank is required.

  Specifically, the heat source control device 270 operates actuators such as the compressor 210, the expansion valve 230, the blower 260, and the electric pump 330. More specifically, in one heat pump cycle, a target temperature difference ΔTo (for example, 10 ° C.) that is a temperature difference between the low-temperature hot water flowing into the water heat exchanger 220 and the high-pressure refrigerant flowing out of the water heat exchanger 220. And the refrigerant pressure on the high pressure side is controlled by changing the opening of the expansion valve 230 based on the target temperature difference ΔTo.

  On the other side of the circulating water circuit, the electric pump 330 is controlled so as to adjust the flow rate flowing out of the water heat exchanger 220 so that the actual boiling temperature detected by the second hot water temperature sensor 274 becomes the target boiling temperature. The number of revolutions is controlled. This will be described based on the flowchart shown in FIG.

  First, as shown in FIG. 3, in step 110, it is determined whether or not there is an operation command for boiling operation. Here, if there is an operation command, control of the electric pump 330 is started, and if there is no operation command, it waits until there is an operation command. In step 120, the actual boiling temperature detected by the second hot water temperature sensor 274 is read and stored.

  Next, in step 130, based on the actual boiling temperature, the target rotational speed that becomes the target boiling temperature is obtained by PID control or fuzzy theory, and the voltage output that is the instruction voltage that becomes the target rotational speed is obtained. Calculate the value.

  In step 140, a voltage output value is output to the instruction voltage means 270a. In step 150, the actual rotational speed obtained from the rotational speed detection means 270b is compared with the target rotational speed, and a deviation which is the difference between these is calculated.

  Next, in step 160, it is determined whether or not the obtained deviation is a predetermined value (for example, 100 rpm) or more. Here, if the deviation is equal to or greater than the predetermined value, the process proceeds to step 170.

  In step 170, the voltage output value is corrected and the corrected voltage output value is output to the instruction voltage correction means 270c. Here, the voltage output value to be corrected according to the deviation is more specifically, as shown in FIG. 4, for example, if the target rotational speed is +500 rpm than the actual rotational speed, +1 V is added as a correction voltage. To instruct. Here, means for correcting the voltage output value according to the deviation is referred to as correction means in the claims.

  Then, after outputting the corrected voltage output value, the process returns to step 150 to obtain the deviation between the actual rotational speed and the target rotational speed. If the deviation is less than the predetermined value in step 160, the process proceeds to step 120 because the actual rotational speed and the target rotational speed are approximated.

  By performing the control as described above, the actual rotational speed of the electric pump 330 can be accurately changed to the target rotational speed that is the target boiling temperature. By the way, in the electric pump 330 which consists of this kind of DC brushless motor, there exists a problem that an actual rotational speed varies with respect to a target rotational speed by changing the rotational speed via a voltage output value due to variations of the single motor.

  This will be described based on the characteristic diagram shown in FIG. 5. When the power output value V is output, the actual rotational speed varies in the range of N1 to N2 due to the variation of the single motor. In addition, as shown in FIG. 6, when this type of electric pump 330 is disposed in the circulating water circuit 320, a lower limit of the rotational speed at which the flow rate flowing out of the water heat exchanger 220 becomes a predetermined amount or more is required.

In other words, when the flow rate flowing out of the water heat exchanger 220 is 0 L / min, problems such as boiling in the heat pump cycle, abnormal stop of the heat pump unit due to abnormal increase in high pressure, and deterioration of durability occur. To do. Therefore, in order to prevent these problems, it is necessary to set a lower limit of the rotational speed (for example, the rotational speed N ₀ ).

More specifically, the electric pump 330 used in the circulating water circuit 320 must have a lower limit of the number of rotations of N ₀ or more as the minimum number of rotations at which the flow rate becomes a predetermined amount or more. When this is determined by the voltage output value, as shown in FIG. 5, in order for the lower limit of the rotation speed to be N ₀ or more, the voltage output value must be V ₀ or more.

As described above, for example, when the actual boiling temperature is lower than the target boiling temperature in the transient state where the boiling operation is started, the electric pump 330 is used to increase the actual boiling temperature. By causing the voltage output value to be output to the minimum voltage output value V ₀ or more, problems in the heat pump cycle can be prevented.

  According to the hot water storage type hot water supply apparatus according to the above-described embodiment, the heat source control device 270 calculates the target rotational speed that becomes the target boiling temperature based on the actual boiling temperature and the voltage output value that provides the target rotational speed. A correction means (step 170) is provided for outputting the voltage output value to the electric pump 330 and correcting the voltage output value in accordance with the actual rotational speed.

  According to this, the electric pump 330 that changes the rotation speed via the voltage output value generally has a problem that the actual rotation speed varies with respect to the target rotation speed due to variations of the single motor. Therefore, in the present invention, the correction means (step 170) for correcting the voltage output value according to the actual rotational speed is provided, so that it is possible to converge to an accurate target rotational speed by absorbing the variation of the single motor. . Thereby, the controllability of the flow rate of the electric pump 330 is improved.

  More specifically, the correcting means (step 170) compares the actual rotational speed with the target rotational speed to obtain a deviation, corrects the command voltage based on the deviation, and thereby outputs a voltage output value based on the deviation. By correcting this, it is possible to reliably absorb variations in the single motor.

  Further, the electric pump 330 is set with a lower limit flow rate of hot water flowing out of the water heat exchanger 220, and the heat source control device 270 is based on a target rotational speed at which the voltage output value does not fall below the lower limit flow rate. Therefore, when the actual boiling temperature is increased, the minimum voltage output value does not fall below the lower limit flow rate. Therefore, the heat pump unit 200 is heated due to boiling in the heat pump cycle, abnormal increase in high pressure, etc. Abnormal stop can be prevented.

  The heat pump unit 200 is characterized by being composed of a supercritical heat pump cycle in which the refrigerant pressure on the high temperature side is equal to or higher than the critical pressure of the refrigerant. Hot water (for example, about 85 ° C.) can be stored in the hot water storage tank 310.

(Other embodiments)
In the above embodiment, the heat source control device 270 is configured such that the voltage output value output to the electric pump 330 is obtained based on the lower limit rotational speed that does not fall below the lower limit flow rate. The heat source controller 270 is configured to control the rotational speed of the electric pump 330 by fixing the voltage output value when the voltage output value output to the electric pump 330 is a rotational speed that does not fall below the lower limit flow rate. May be.

  According to this, it can be applied during the freeze prevention operation of the circulating water circuit 320 of the electric pump 330 and the air venting operation of the circulating water circuit. In this case, power saving and noise reduction can be obtained by operating at the minimum rotational speed.

It is a schematic diagram which shows the whole structure of the hot water storage type hot water supply apparatus in one Embodiment of this invention. It is an electric block diagram of the heat source control apparatus 270 which controls the electric pump 330 in one Embodiment of this invention. It is a flowchart which shows the control processing of the heat-source control apparatus 270 in one Embodiment of this invention. It is explanatory drawing which shows the specific example which correct | amends a voltage output value according to the deviation in the correction | amendment means in one Embodiment of this invention. It is a characteristic view which shows the relationship between the voltage output value of the electric pump 330 in one Embodiment of this invention, and rotation speed. It is a characteristic view which shows the relationship between the flow volume and rotation speed of the electric pump 330 in one Embodiment of this invention.

Explanation of symbols

170 ... Correction means 200 ... Heat pump unit 210 ... Compressor 220 ... Water heat exchanger (radiator)
270 ... Heat source control device (control means)
310 ... Hot water storage tank 330 ... Electric pump

Claims (5)

A hot water storage tank (310) for storing hot water supply fluid;
A heat pump cycle, which heat-exchanges the refrigerant discharged from the compressor (210) and hot water supply fluid, and has a radiator (220) configured to oppose the refrigerant flow and the hot water supply fluid flow, A heat pump unit (200) that conducts a boiling operation by introducing a hot water supply fluid in the hot water storage tank (310) to the radiator (220);
An electric pump (330) for passing the hot water supply fluid taken out from the lower part of the hot water storage tank (310) through the radiator (220) and pumping it to the upper part of the hot water storage tank (310);
Control means (270) for controlling the rotational speed of the electric pump (330) so that the boiling temperature of the hot water supply fluid flowing out from the radiator (220) becomes a target boiling temperature;
The control means (270) obtains a target rotational speed at which the target boiling temperature is obtained based on the boiling temperature and an instruction voltage for obtaining the target rotational speed, and outputs the instruction voltage to the electric pump (330). A hot water storage type hot water supply apparatus comprising correction means (170) for correcting the indicated voltage in accordance with an actual rotational speed.   The hot water storage hot water supply according to claim 1, wherein the correction means (170c) obtains a deviation by comparing an actual rotational speed with a target rotational speed, and corrects the command voltage based on the deviation. apparatus. The electric pump (330) is set with a lower limit flow rate of the hot water supply fluid flowing out of the radiator (220),
The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein the control means (270) is obtained based on a rotation speed at which the command voltage does not fall below the lower limit flow rate.   The control means (270) controls the rotational speed of the electric pump (330) by fixing the command voltage when the command voltage is at a rotational speed that does not fall below the lower limit flow rate. The hot water storage type hot water supply apparatus according to any one of claims 1 to 3.   The said heat pump unit (200) is comprised from the supercritical heat pump cycle from which the refrigerant | coolant pressure of a high temperature side becomes more than the critical pressure of a refrigerant | coolant, The Claim 1 thru | or 4 characterized by the above-mentioned. Hot water storage water heater.

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