JPH0434366Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field> The present invention relates to a heat pump type heat collection and storage device that produces hot water using the principle of a heat pump.

<Prior Art> Conventionally, in a heat pump that is composed of a combination of a heat pump unit and a heat storage unit and uses late-night electricity, an auxiliary electric heater is provided below the heat storage tank. This is because the heating capacity of the heat pump changes depending on the outside air temperature, water temperature, etc. as shown in Figure 2, and heats the fluid in the heat storage tank to the set temperature within the midnight electricity supply time (generally 8 hours). This is because the capacity of heat pumps is low in winter when the outside temperature is low, so an auxiliary electric heater becomes necessary. That is, when the outside temperature is low, a heat pump and an auxiliary electric heater are used in combination, or only the auxiliary electric heater is used for heating. However, the heating efficiency of auxiliary electric heaters is about 1/2 to 1/2 that of heat pumps even at low outside temperatures.
The result was that the heat pump lacked energy saving performance.

<Purpose> In view of the above, the present invention aims to provide a heat pump type heat collection and storage device that can vary the rotation speed of the compressor and heat the fluid in the heat storage tank to a set temperature within a certain period of time. .

<Embodiment> Hereinafter, an embodiment of the present invention using late-night electricity will be described. This includes an evaporator 1 that absorbs outside air heat, a compressor 2 that discharges heat medium heated by the evaporator 1, In a heat pump type heat collection and storage device in which a heat pump cycle 5 is configured by sequentially connecting a heat exchanger 4 which radiates heat from the heat medium discharged from the compressor 2 to a fluid on the side of a heat storage tank 3 through heat medium pipes 5A and 5B. , the compressor 2 has a variable rotation speed, and is provided with a control device 6 that controls the rotation speed of the compressor 2. The control device 6 includes an outside temperature detector 7 that detects outside temperature, and a heat storage tank 3. The fluid in the heat storage tank 3 can be heated to a set temperature within a certain period of time by a fluid temperature detector 8 that detects the temperature of the fluid in the heat storage tank 3, and input signals from the outside temperature detector 7 and the fluid temperature detector 8. 2, and a control circuit 10 for controlling the rotation speed of the compressor 2.

The compressor 2, the evaporator 1, the blower 11, the expansion valve 12, and the frequency of the late-night power are converted and the compressor 2
A power frequency converter 13 for changing the rotation speed of the heat pump unit 1 is installed in the case 14a.
4 are configured. Further, the heat storage tank 3 and the heat exchanger 4 constitute a heat storage unit 15. The heat exchanger 4 includes a fluid circulation circuit 3A that takes out and circulates the fluid in the heat storage tank 3 to the outside.
It has a double pipe structure consisting of an inner pipe 16 and an outer pipe 17 through which the heat medium discharged from the compressor 2 flows, and is fixed to the upper part of the heat storage tank 3 in a spiral manner. In addition, in the figure, 18 is a fluid circulation pump provided in the fluid circulation circuit 3A, 19 is a hot water supply pipe on the upper part of the heat storage tank 3, and the hot water from the hot water supply pipe 19 is for shower A,
It is provided as B for bathing, C for washing, and D for cooking.
Reference numeral 20 indicates a fluid supply port at the bottom of the heat storage tank 3, and 21 indicates an auxiliary electric heater at the bottom of the heat storage tank 3.

Further, the outside temperature detector 7 is made up of a thermistor installed at an arbitrary location outdoors, and the fluid temperature detector 8 is made up of a thermistor installed inside the heat storage tank 3. Furthermore, the control circuit 10 is programmed internally by a general one-chip microcomputer.
It has ROM, data RAM, ALU, etc., and is driven by a reference clock oscillation circuit. That is, control circuit 1
0 is from a heating capacity storage means 30 that stores the heating capacity according to the rotation speed of the compressor 2 for a combination of the outside temperature and the fluid temperature, and the outside temperature detector 7 and the fluid temperature detector 8. The compressor control means 31 controls the compressor 2 with the heating capacity stored in the heating capacity storage means 30 based on the input signal. Output signals from the outside temperature detector 7, fluid temperature detector 8, power supply detection circuit 23, and operation panel 24 are input to the input port of the control circuit 10. The control circuit 10 is configured to count the set time based on the input signal of the power supply detection circuit 23. An output signal is output from the output port of the control circuit 10 to the power frequency converter 13 and the operation panel 24.

In the above configuration, the heat pump unit 13
Then, the heat medium compressed by the compressor 2 passes through the heat medium pipe 5A at high temperature and high pressure, and the heat exchanger 4 heats the fluid in the heat storage tank 3 sent by the pump 18, and liquefies the heat medium. . The liquefied heat medium passes through the heat medium pipe 5B, is depressurized by the expansion valve 12, takes heat from the outdoor air in the evaporator 1, vaporizes, and returns to the compressor 2. Here, the power source for the compressor 2 is supplied with late-night power via the power frequency converter 13, and the compressor 2
is a power supply frequency of about 30 to 120 Hz, the rotation speed of the compressor 2 changes from about 1500 to 6000 rpm accordingly, and the heating capacity of the heat pump becomes variable.

Figure 2a shows the general relationship between the heating capacity of a heat pump and the outside temperature.When the outside temperature is low, such as in winter, the amount of heat absorbed from the outside air is small, and the heating capacity of the heat pump is also small. During high outside temperatures such as in summer,
The amount of heat absorbed from the outside air also increases, increasing the heating capacity of the heat pump.

In addition, Figure 2b shows the general relationship between the heating capacity of the heat pump and the temperature (water temperature) of the fluid (water) in the heat storage tank 3. When the temperature of the fluid in the heat storage tank 3 is low, the heating capacity of the heat pump required to raise the temperature of the fluid to the set temperature increases; The heating capacity of the heat pump required to raise the temperature of the fluid to the set temperature is small.

As described above, the heating capacity of the heat pump depends on the outside air temperature and the temperature of the fluid, so when the outside air temperature is low or the water temperature is low, such as in winter, the compressor control means 31 stores the heating ability in the heating ability storage means 30. Based on the heating capacity obtained, the compressor 2 is rotated at high speed to increase the heating capacity of the heat pump.

On the other hand, when the outside temperature is high or the water temperature is high, such as in summer (including when there is residual hot water), the compressor 2 is controlled to rotate at a low speed to reduce the heating capacity of the heat pump. For example, if the performance of a heat pump is expressed as shown in Figure 3, in order to raise the water temperature inside the 370 tank to 75℃, it is necessary to
℃, and the water supply temperature is 5℃), the required heating capacity of the heat pump is 370 x (75-5)/8≒3240kcal/h, assuming a late-night power supply period of 8 hours.Therefore, if the power supply frequency is approximately 110Hz, good.

Also, in summer (when the outside temperature is 21.7℃ and the water supply temperature is 15℃, 370×(75−15)/8≒2780kcal/h. Therefore, it is possible to heat the power source even if the power frequency is 30Hz or less. In this case, the actual It runs at 30Hz and stops when the water temperature reaches 75℃.In this way, you can boil the water within 8 hours.

<Effects> As is clear from the above explanation, the present invention includes an evaporator that absorbs outside air heat, a compressor that discharges heat medium heated by the evaporator, and a heat storage system that stores heat from the heat medium discharged from the compressor. In a heat pump type heat collection and storage device in which a heat pump cycle is configured by sequentially connecting a heat exchanger that radiates heat to a fluid on the tank side through heat medium piping,
The compressor has a variable rotation speed, and is provided with a control device that controls the rotation speed of the compressor, and the control device includes an outside temperature detector that detects outside temperature and a temperature of the fluid in the heat storage tank. control for controlling the rotation speed of the compressor so that the fluid in the heat storage tank can be heated to a set temperature within a certain period of time based on input signals from the outside temperature detector and the fluid temperature detector; The control circuit includes a heating capacity storage means that stores a heating capacity according to the number of revolutions of the compressor for a combination of outside temperature and fluid temperature, and a heating capacity storage means that stores the heating capacity according to the rotation speed of the compressor, and Compressor control means is provided for controlling the compressor with the heating capacity stored in the heating capacity storage means based on the input signal from the temperature detector.

Therefore, according to the present invention, in winter when the outside temperature is low or when the fluid temperature is low, the compressor is rotated at high speed and the heating capacity of the heat pump is increased to bring the fluid in the heat storage tank to the set temperature within a certain period of time. It is possible to reduce the use of auxiliary electric heaters as much as possible, which is required in the past, and save on electricity costs. By reducing the rotation speed of the heat pump, it is possible to reduce the heat pump's capacity and save on electricity costs.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a heat pump type heat collection and storage device showing an embodiment of the present invention, Fig. 2a is a diagram showing a general relationship between outside air temperature and heating capacity of a heat pump,
Figure 2b is a diagram showing the general relationship between water temperature and heating capacity of a heat pump, Figure 3 is a diagram showing an example of controlling the heating capacity of a heat pump with respect to water temperature and outside air temperature, and Figure 4 is a control circuit. FIG. 1... Evaporator, 2... Compressor, 3... Heat storage tank,
4...Heat exchanger, 5...Heat pump cycle,
6...Control device, 7...Outside temperature detector, 8...Fluid temperature detector, 10...Control circuit, 30...Heating ability storage means, 31...Compressor control means.

Claims (1)

[Scope of claim for utility model registration] An evaporator that absorbs outside air heat, a compressor that discharges heat medium heated by the evaporator, and radiates heat from the heat medium discharged from the compressor to a fluid on the heat storage tank side. In a heat pump type heat collection and storage device in which a heat pump cycle is configured by sequentially connecting a heat exchanger with a heat medium piping, the compressor has a variable rotation speed, and a control device for controlling the rotation speed of the compressor is provided. , the control device includes: an outside temperature detector that detects the outside temperature; a fluid temperature detector that detects the temperature of the fluid in the heat storage tank; and a control circuit that controls the rotation speed of the compressor so that the fluid in the tank can be heated to a set temperature within a certain period of time, and the control circuit is configured to control the rotation speed of the compressor according to the combination of the outside temperature and the fluid temperature. heating capacity storage means for storing heating capacity according to the rotational speed of the heating capacity storage means; and heating capacity stored in the heating capacity storage means based on input signals from the outside temperature detector and the fluid temperature detector. 1. A heat pump type heat collection and storage device comprising a compressor control means for controlling a compressor.