JPH10176873A - Heat pump device and control method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the load factor of a turbo heat pump by a method wherein, during heating operation, hot water, the temperature of which is increased by the turbo heat pump, is caused to pass through an absorption cold and hot water unit to increase temperature, and the turbo heat pump and the absorption type cold and hot water unit are controlled so that a hot water outlet temperature is adjusted to a specified temperature. SOLUTION: During heating operation, valves 10 and 11 are opened and heat source water is inputted to a vaporizer 1 of a turbo heat pump THP through a flow passage 7 by a pump 9. Further, a three-way valve 21 is switched and hot water at a cold and hot water return head 12A is caused to flow to a condenser 2 of a THP through pipings 19 and 26 by a pump 30. Hot water flowing out from the condenser 2 is caused to flow to the condenser of an absorption cold and hot water unit AHU and further flows through a valve 18, and hot water the temperature of which is increased is guided to a cold and hot water header 12B. In this case, the outlet hot water temperature of the condenser 2 is detected by a temperature sensor 27, and by controlling the THP and the AHU so that the outlet hot water temperature is adjusted to a specified temperature, the load factor of the THP is increased and energy efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a heat pump device and a control method thereof.

[0002]

2. Description of the Related Art In a conventional heat pump device, a turbo heat pump and an absorption type cold / hot water unit are arranged in parallel, and control is performed so that the hot water outlet temperature of each unit becomes constant.

[0003] Japanese Patent Application Laid-Open No. Sho 62-190364 is a related example of this type.

[0004]

In the above heat pump device, both the turbo heat pump and the absorption type chilled / hot water unit are operated in a reduced amount at the time of partial load, and the energy efficiency is poor.

[0005] In addition, when the turbo heat pump is used for cooling and when it is used for heating, the head difference of the compressor of the turbo heat pump becomes large, so that the efficiency of the compressor of the turbo heat pump during cooling decreases, and However, there is a problem in that the energy efficiency of the turbo heat pump is significantly lower than that of a turbo refrigerator exclusively used for cooling.

Furthermore, it is generally known that if the head difference between the design points of the turbo heat pump during heating and during cooling is reduced, efficient operation for both cooling and heating can be performed. No effective means has been known for reducing the head difference between the head required for heating and the head required for heating.

[0007] Further, it is effective means to improve the efficiency by increasing the load factor of the efficient turbo heat pump and reducing the load factor of the absorption type chilled and heated water unit at the time of partial load during heating, but preferentially. No effective means for increasing the load factor of a turbo heat pump has been known.

The present invention reduces the difference between the head required for cooling of the turbo heat pump and the head required for heating, and reduces the load factor of the turbo heat pump at the partial load during heating. An object of the present invention is to provide a heat pump device that increases the load factor and a control method thereof.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat pump apparatus for cooling and heating by combining a turbo heat pump and an absorption type cold and hot water unit, wherein hot water heated by the turbo heat pump is heated during heating. This is achieved by controlling the turbo heat pump and the absorption type cold / hot water unit such that the hot water is further heated by passing the water through the unit, and the hot water outlet temperature of the turbo heat pump becomes a constant temperature.

Another object of the present invention is to provide a heat pump apparatus for cooling and heating by combining a turbo heat pump and an absorption type cooling / heating water unit. In heating, hot water heated by the turbo heat pump is passed through the absorption type cooling / heating water unit. Further, the temperature of the hot water is further increased, and cooling is achieved by operating the turbo heat pump and the absorption type cooling / heating water unit in parallel to reduce the difference in design points between the time of cooling and the time of heating of the turbo heat pump. .

Further, the object of the present invention is to provide a control method of a heat pump apparatus for performing cooling and heating by combining a turbo heat pump and an absorption type cooling and heating water unit. During the heating, a signal of the lower limit of the capacity control of the absorption-type cold / hot water unit is transmitted to the turbo heat pump so that the hot water is further heated so that the hot water outlet temperature of the turbo heat pump becomes a constant temperature. Until the reduction of the operation of the turbo heat pump is stopped, this is achieved.

Further, the object of the present invention is to provide a control method of a heat pump device for performing cooling and heating by combining a turbo heat pump and an absorption type cooling and heating water unit. The hot water is further heated to raise the temperature of the hot water, and the capacity control of the absorption-type cold / hot water unit is controlled so that the hot water temperature at the inlet of the turbo heat pump becomes constant. This is achieved by controlling the outlet hot water temperature of the boat pump to a constant temperature.

The heat pump device having the above-described structure operates as follows. During heating, the hot water heated by the turbo heat pump is passed through the absorption type chilled / hot water unit to further raise the temperature.At the time of cooling, the turbo heat pump and the absorption type chilled / hot water unit are used in parallel. In a state where a high temperature of hot water is required during heating, the temperature of the hot water of the turbo heat pump is raised again by the absorption type cold / hot water unit in order to raise the temperature of the hot water of the turbo heat pump. .

Therefore, the required head of the turbo heat pump at the time of heating can be kept low, the head difference between the design points of the turbo heat pump at the time of cooling and at the time of heating can be reduced, and both cooling and heating are efficient. Driving becomes possible. Further, during heating in the heat pump, the turbo heat pump and the absorption-type cold / hot water unit are controlled such that the hot water outlet temperature of the turbo heat pump becomes constant.

As shown in FIG. 2, if the heating load and the heating capacity of the heat pump match in the reduction range of the absorption type chilled / hot water unit, the temperature of the hot water returning from the load side to the turbo heat pump becomes almost constant. If the outlet temperature of the heat pump is controlled to be constant, the turbo heat pump can be controlled to always operate at a constant (maximum load), and the load factor of the turbo heat pump can be increased.

[0016]

FIG. 1 is a system diagram of a heat pump apparatus according to one embodiment of the present invention. In FIG. 1, 1 is an evaporator of a turbo heat pump THP, 2 is a condenser of a turbo heat pump THP, and 3 is a turbo heat pump THP.
Is a capacity control device for controlling the capacity of the power supply. Reference numeral 4 denotes an evaporator of the absorption-type cold / hot water unit AHU, and reference numeral 5 denotes a condenser / absorber of the absorption-type cold / hot water unit AHU. Reference numeral 6 denotes a capacity control device for controlling the capacity of the absorption-type hot / cold water unit AHU. The evaporator 1 is connected to a pipe 8A for taking in heat source water from a pipe 7 through which heat source water flows, and a pipe 8B for returning heat source water to the pipe 7 again using heat of the heat source water. A pump 9 and an on-off valve 10 are attached to the pipe 8A, and an on-off valve 11 is attached to the pipe 8B.

The evaporator 4 of the absorption-type cold / hot water unit AHU has a cold / hot water return header 1 in which cold / hot water returned from the load is stored.
A pipe 13 for entering cold and hot water from 2A and a pipe 14 for returning cold and hot water to a cold and hot water header 12B where cold and hot water returning to the load is stored.
Is connected. A pump 15 and an on-off valve 1
The pipe 14 is provided with a temperature sensor 17 for detecting the temperature of cold and hot water and an on-off valve 18.

The evaporator 1 of the turbo heat pump THP is connected to a pipe 19 for receiving cold and hot water from the cold and hot water return header 12A and a pipe 20 for returning cold and hot water to the cold and hot water header 12B. . A three-way valve 21, a pump 22, and an on-off valve 22B are attached to the pipe 19, and a temperature sensor -23 for detecting the temperature of cold or hot water is attached to the pipe 20,
On-off valve 23B is attached.

A cooling tower 24 is connected to the condenser 2 of the turbo heat pump THP by pipes 25 and 26.
The pipe 25 is provided with a temperature sensor 27 for detecting the temperature of the cooling water, and a three-way valve 28B for switching the flow of the cooling water between the pipe 25 and the pipe 13. Piping 2
6 is provided with an on-off valve 29, a pump 30, and a temperature sensor 31 for detecting the temperature of the cooling water.

The condenser / absorber 5 of the absorption type hot / cold water unit AHU and the cooling tower 24 are connected by a pipe 32, and a pump 33 and an on-off valve 35 are attached to the pipe 32.

The capacity control device 3 of the turbo heat pump THP is connected so as to input the signals of the temperature sensors 23 and 27, and the capacity control device 6 of the absorption type cold water unit AHU has the temperature sensors 17 and 31 connected thereto. It is connected so that a signal may be input. In addition, turbo heat pump THP
Are connected so that a control signal is mutually inputted between the capacity control device 3 and the capacity control device of the absorption-type hot / cold water unit AHU.

Next, the operation of the heat pump device having the above configuration will be described. First, in the case of heating, the valves 10 and 11 are opened, and the heat source water is taken in from the flow path 7 to the evaporator 1 of the turbo heat pump THP by the pump 9. The three-way valve 21 is switched, and the pump 30
From 9 and 26, the hot water of the cold / hot water return header 12A is passed to the condenser 2 of the turbo heat pump THP.

The operation of the pump 30 allows hot water to flow. Switching the three-way valve 28B, the turbo heat pump T
The hot water flowing out of the HP condenser 2 is an absorption type cold / hot water unit A
The hot water that has passed through the condenser of the HU and has been heated by opening the valve 18 is led to the cold / hot water header 12B. The outlet temperature of the hot water discharged from the condenser 2 of the turbo heat pump THP is detected by the temperature sensor 27, and the turbo heat pump THP and the absorption-type cold / hot water unit AHU are controlled so that the relationship shown in FIG. Increase the load factor of the heat pump THP.

At the time of heating, the temperature sensor 31 detects the hot water inlet temperature of the turbo heat pump THP in order to realize the relationship shown in FIG. The capacity control device 6 of the absorption-type cold / hot water unit AHP controls the absorption-type cold / hot water unit AHP so that the detection value of the temperature sensor 31 becomes constant. When the capacity control becomes the lower limit, the capacity control device 6 of the absorption-type cold / hot water unit AHP sends a signal to the capacity control device 3 of the turbo heat pump THP. With that signal,
The capacity control device 3 of the turbo heat pump THP starts the reduction operation. When the load is reduced beyond the reduction control range, the turbo heat pump THP detects an increase in the hot water outlet temperature with the temperature sensor 23 and stops the operation. Turbo heat pump THP with predetermined differential
When the hot water outlet temperature decreases, the operation is restarted. The absorption-type cold / hot water unit AHP stops the operation when the hot water inlet temperature of the turbo heat pump THP becomes equal to or higher than a predetermined temperature, and restarts the operation when the hot water inlet temperature decreases with a predetermined differential. .

Next, the cooling operation will be described. The on-off valves 16, 22B and 23B are opened, and the on-off valves 10, 11
Is closed, and the cold water pumps 15 and 22 are operated to supply cold water to the turbo heat pump THP and the absorption type cold / hot water unit AHU. Here, the temperature is measured by the temperature sensors 17 and 23, and the turbo heat pump THP and the absorption-type cold and hot water unit AHU are controlled by the respective capacity controllers 3 and 6 so that the cold water outlet temperature becomes constant. The cooling water is opened by the on-off valves 29 and 35 and the cooling water cooled by the cooling tower 24 is pumped by the pumps 30 and 33 to the turbo heat pump TH.
Water is passed through the condenser 2 of P, the condenser 5 of the absorption-type cold / hot water unit AHU, and the absorber 4.

[0026]

As described above, in a heat pump device for cooling and heating by combining a turbo heat pump and an absorption type cooling / heating water unit, energy efficiency can be improved by increasing the load factor of the turbo heat pump during heating. Further, during cooling, the head required for cooling and heating of the turbo heat pump can be reduced, so that energy-efficient operation can be performed, and energy can be saved both during cooling and during heating.

[Brief description of the drawings]

FIG. 1 is a system diagram of a heat pump device according to one embodiment of the present invention.

FIG. 2 is an explanatory diagram of control during heating in the embodiment of FIG. 1;

[Explanation of symbols]

THP: Turbo heat pump, AHP: Absorption type cold / hot water unit, 1: Turbo heat pump evaporator, 2: Turbo heat pump condenser, 3: Capacity control device, 4: Absorption type cold / hot water unit evaporator, 5: Absorption type Condenser / absorber of cold / hot water unit, 6: capacity control device, 7, pipe for flowing heat source water, 9, 15, 22, 30, 33 ... pump 10, 11, 16, 18, 22B, 23B, 29, 35
... On-off valve, 12A ... Cold and hot water return header, 12B ... Cool and hot water header, 17, 23, 27, 31 ... Temperature sensor, 21, 28B ... Three-way valve, 24 ... Cooling tower.

Claims (4)

[Claims] In a heat pump apparatus for cooling and heating by combining a turbo heat pump and an absorption type cold / hot water unit, during heating, hot water heated by the turbo heat pump is passed through the absorption type cold / hot water unit to further supply hot water. The temperature of the turbo heat pump is controlled so that the hot water outlet temperature of the turbo heat pump becomes constant. 2. A heat pump apparatus for cooling and heating by combining a turbo heat pump and an absorption type cold / hot water unit, wherein, during heating, hot water heated by the turbo heat pump is passed through the absorption type cold / hot water unit to further supply hot water. A heat pump device characterized in that the turbo heat pump and the absorption-type cooling / heating water unit are operated in parallel during cooling to reduce the difference in design between the cooling and heating of the turbo heat pump. 3. A method of controlling a heat pump apparatus for performing cooling and heating by combining a turbo heat pump and an absorption type cold / hot water unit, wherein hot water heated by the turbo heat pump is passed through the absorption type cold / hot water unit during heating. Further warming the hot water, so that the hot water outlet temperature of the turbo heat pump to a constant temperature, during heating, until the signal of the capacity control lower limit of the absorption type cold and hot water unit is transmitted to the turbo heat pump, A method for controlling a heat pump device, comprising: stopping a reduction operation of a turbo heat pump. 4. A method of controlling a heat pump apparatus for performing cooling and heating by combining a turbo heat pump and an absorption type cooling and heating water unit, wherein hot water heated by the turbo heat pump is passed through the absorption type cooling and heating water unit during heating. The temperature of the hot water is further increased by heating, and the capacity control of the absorption type cold / hot water unit is controlled so that the temperature of the hot water at the inlet of the turbo heat pump becomes constant, and the turbo heat pump is the turbo heat pump. A method for controlling a heat pump device, wherein the outlet hot water temperature is controlled to be constant.