WO2007059709A1 - A heat pump system for air conditioning under a low temperature and a using method thereof - Google Patents

Abstract

A heat pump system for air conditioning under a low temperature (100) and a method for decreasing fluctuation of temperature conditioning using the same are disclosed. The heat pump system (100) for air conditioning under a low temperature comprises a compressor (11), a four-way valve (16), an outdoor heat exchanger (17), an outdoor electronic expansion valve (18), a liquid reservoir (12), an electronic expansion valve (13) and an indoor heat exchanger (22). The liquid reservoir (12) is connected to the gas supplementing port of the compressor (11) through a pipe provided with an electromagnetic valve (14) for supplementing saturated refrigerant gas under a middle pressure to the compressor (11). When the outdoor temperature is lower than zero degree, the electromagnetic valve (14) is opened, and the open degree of the electronic expansion valve (13) is controlled according to the temperature between the liquid reservoir (12) and the electronic expansion valve (13) and the temperature between the electromagnetic valve (14) and the compressor (11). Then saturated refrigerant gas under a suitable middle pressure is supplemented to the compressor (11).

Description

 Low-temperature air-conditioning heat pump system and method for reducing temperature regulation fluctuation using the same

 The invention relates to the field of air source heat pump air conditioners, in particular to a low temperature air conditioning heat pump system with good heating effect under outdoor low temperature working conditions and a method for reducing temperature regulation fluctuation.

 Background technique

 At present, the ordinary air source heat pump air conditioning unit sold in the market, under the outdoor low temperature conditions, the heat generation attenuation is very serious, and even can not start normally. It can only be used in the transitional season in the cold regions of northern China, and cannot be used in the cold winter. Meet basic heating needs. The traditional centralized supply methods in northern China are mainly coal-fired and gas-fired, and these methods of supply are unable to meet the requirements of social development in terms of energy conservation, environmental protection and safety. Therefore, it is necessary to develop an ultra-low temperature heat pump air conditioning unit to replace the traditional central heating method in northern China.

Summary of the invention

 SUMMARY OF THE INVENTION An object of the present invention is to provide a low temperature air conditioning heat pump system which has a good heating effect in the case of outdoor low temperature operation.

 Another object of the present invention is to provide a method of reducing temperature adjustment fluctuations using the above-described low temperature air conditioning heat pump system.

 In order to achieve the above object, the present invention adopts the following technical solutions: Providing a low temperature air conditioning heat pump system comprising a series connected four-way valve, an outdoor unit heat exchanger and an outdoor unit electronic expansion valve, the low temperature air conditioning heat pump system further comprising A compressor air supply system that supplements an intermediate pressure saturated refrigerant gas, and the compressor air supply system is connected to the four-way valve and the outdoor electronic expansion valve, respectively.

In the present invention, the compressor air supply system includes a liquid reservoir, a solenoid valve, an electronic expansion valve, and a confirmation book. And a compressor provided with a gas supply port; the liquid storage device is respectively connected to the electromagnetic valve and the electronic expansion valve, and the air supply port of the compressor is connected with the electromagnetic valve.

 In the present invention, the compressor air supply system further includes two temperature sensing packages, including a first temperature sensing package for measuring a temperature value between the electromagnetic valve and the compressor, and measuring the electronic expansion valve and the A second temperature sensing package for the temperature value between the reservoirs.

 In the present invention, the temperature sensing package is a thermistor.

 In the present invention, the accumulator and the electromagnetic valve and the electronic expansion valve are respectively connected by a metal tube, and the compressor and the electromagnetic valve are connected by a metal tube, and the first temperature sensing package is placed A surface of the metal tube connecting the compressor and the solenoid valve, the second temperature sensing package being placed on a surface of the metal tube connecting the liquid reservoir and the electronic expansion valve.

 In the present invention, the compressor is a jet-enhanced digital scroll compressor.

 The cryogenic air conditioning heat pump system of the present invention further includes a gas-liquid separator and a sub-cooling coil; the gas-liquid separator is connected between the four-way valve and the compressor; the sub-cooling coil is connected to the An outdoor electronic expansion valve is interposed between the reservoir.

 In order to achieve the above other object, the present invention adopts the following technical solution: Providing a method for reducing temperature regulation fluctuation of an air conditioning heat pump system includes the following steps:

 Step 1: Configure the compressor air supply system;

 Step 2: Replenish the intermediate pressure saturated refrigerant gas through the compressor air supply system.

In the first step: first preparing a compressor with a gas supply port, a solenoid valve, an electronic expansion valve, and a reservoir; then connecting one end of the solenoid valve to a gas supply port of the compressor through a copper tube, and connecting The other end of the solenoid valve is connected to the accumulator, and the compressor is connected to the outdoor unit heat exchanger through a four-way valve and a gas-liquid separator; then, one end of the electronic expansion valve is connected to the chamber through a copper tube The reservoir is connected to the other end of the electronic expansion valve to the indoor unit heat exchange system. In the first step, a first temperature sensing package is further disposed on a surface of the metal tube connected to the compressor and the electromagnetic valve, and a surface of the metal tube connected to the electronic expansion valve Placing a second temperature sensing package;

 In the second step: first setting a target superheat degree; then: subtracting the temperature values measured by the first temperature sensing packet and the second temperature sensing packet to obtain a first temperature difference; and then: using the above The subtraction of a temperature difference from the target superheat degree results in a second temperature difference, and the opening of the electronic expansion valve is controlled to achieve a saturated refrigerant gas supplementing the intermediate pressure.

 The temperature sensing package is a thermistor; the compressor is a jet-enhanced digital scroll compressor.

 Compared with the prior art, with the low temperature air conditioning heat pump system of the present invention, when the outdoor ambient temperature is lower than zero, the compressor air supply system of the unit functions, the electromagnetic valve is opened, and the opening of the electronic expansion valve is controlled to supplement the compressor. A suitable intermediate pressure saturated refrigerant gas achieves two-stage compression inside the compressor to improve the heat generation and energy efficiency ratio of the unit under outdoor low temperature conditions.

DRAWINGS

 1 is a schematic view showing the internal structure of a low temperature air conditioning heat pump system of the present invention;

Fig. 2 is a compression diagram of the heating operation of the low temperature air conditioning heat pump system of the present invention when the solenoid valve is opened.

detailed description

 Referring to Fig. 1, a low temperature air conditioning heat pump system 100 includes a series connected four-way valve 16, an outdoor unit heat exchanger 17 and an outdoor unit electronic expansion valve 18, and a compressor air supply system. The low temperature air conditioning heat pump system 100 is connected to the indoor unit heat exchanger 22 and the indoor electronic expansion valve 4 to form an entire air conditioning system. The compressor air supply system includes a solenoid valve 14, an electronic expansion pottery 13, and a compressor 11 and a reservoir 12 provided with a gas supply port 12, which is connected to the solenoid valve 14, the electronic expansion valve 13, the compressor 11 and The solenoid valve 14 is connected.

In this embodiment, the low-temperature air-conditioning heat pump system 100 further includes a gas-liquid separator 15 and a sub-cooling Coil 19. The gas-liquid separator 15 is connected between the four-way valve 16 and the compressor to function as a gas-liquid separation. The subcooling coil 19 is connected between the outdoor electronic expansion valve 18 and the accumulator 12.

 In order to better implement the present invention, the compressor air supply system may further include a first temperature sensing package 20 and a second temperature sensing package 21. In the present embodiment, the temperature sensing package is a thermistor, and the compressor is a jet-enhanced digital scroll compressor. The liquid reservoir 12 is connected to one end of the electromagnetic valve 14 and the electronic expansion valve 13 by a metal pipe, and the other end of the compressor 11 and the electromagnetic valve 14 is connected by a metal pipe, and the first temperature sensing bag 20 is placed on the compressor 11 and the electromagnetic valve. 14 The surface of the metal pipe for connection, the second temperature sensing bag 21 is placed on the surface of the metal pipe for connecting the liquid reservoir 12 and the electronic expansion valve 14. The other end of the electronic expansion valve 13 is connected to the electronic expansion valve 4 of the indoor unit. The compressor 11 is connected to the outdoor unit heat exchanger 17 via a four-way valve 16 and a gas-liquid separator 15. One of the four-way valves 16 is connected to the indoor unit heat exchanger 22. The outdoor unit heat exchanger 17 is connected to the accumulator 12 via an outdoor electronic expansion valve 18 and a sub-cooling coil 19.

Referring to FIG. 2, it is preferable that the components of the low-temperature air-conditioning heat pump system 100 are connected by copper pipes. When the low-temperature air-conditioning heat pump system is in the heating operation, the compressor 11 compresses the low-temperature low-pressure refrigerant gas (state point 1) evaporated from the outdoor unit heat exchanger to the intermediate pressure state point 2, at the compressor 11 The gas in the scroll is mixed with the intermediate pressure gas (state point 9) sucked from the compressor air inlet to the state point 10, and then continues to be compressed by the compressor into a high temperature and high pressure gas (state point 3), high temperature and high pressure refrigerant The gas is cooled and condensed into a high-temperature high-pressure refrigerant liquid (state point 4) in the indoor unit heat exchanger 22, and the high-pressure liquid is throttled to an intermediate pressure gas-liquid mixture by the indoor unit electronic expansion valve 4 and the electronic expansion valve 13 (state) After point 5), the accumulator 12 is entered. In the accumulator 12, a part of the refrigerant flashing to the intermediate pressure refrigerant gas (state point 9) is sucked by the compressor air inlet, and another part of the refrigerant in the accumulator 12 is The subcooled liquid (state point 7) that is too cold to the intermediate pressure is throttled to the state point 8 by the outdoor unit electronic expansion valve 18, and then enters the outdoor unit heat exchanger 17 to evaporate to the state point 1 and is sucked by the compressor suction port. Complete a heating cycle ring. A method for reducing temperature regulation fluctuation of an air conditioning heat pump system includes the first step: configuring a compressor air supply system; and second step: supplementing the intermediate pressure saturated refrigerant gas by a compressor air supply system. In the first step: first preparing a compressor with a gas supply port, a solenoid valve, an electronic expansion valve, and a reservoir; then connecting one end of the solenoid valve to the compressed air supply port through a copper tube to connect the electromagnetic The other end of the valve is connected to the accumulator, and the compressor is connected to the outdoor unit heat exchanger through a four-way valve and a gas-liquid separator; then, one end of the electronic expansion valve is connected to the liquid storage through a copper tube And connecting the other end of the electronic expansion valve to the indoor unit heat exchange system. Further, a first temperature sensing package is placed on the surface of the metal tube connected to the compressor and the electromagnetic valve, and a second temperature sensing package is placed on the surface of the metal tube connected to the electronic expansion valve.

 Then in the second step, first set a target superheat; then: subtract the temperature value measured by the first temperature sensing packet and the second temperature sensing packet to obtain a first temperature difference; then: using the above The subtraction of a temperature difference from the target superheat results in a second temperature difference, and controls the opening of the electronic expansion valve to 'achieve a saturated refrigerant gas that supplements the intermediate pressure.

 SUMMARY OF THE INVENTION The present invention is directed to the use of a compressor air entrainment system to reduce the amount of heat generation attenuation of an air conditioning heat pump system during low temperature operation, which is not to be considered as limiting the invention. If a person skilled in the art makes non-substantial, obvious changes or improvements in accordance with the present invention, it should fall within the scope of the claims of the present invention.

Claims

Rights request 1. A low temperature air conditioning heat pump system comprising a series connected four-way valve, an outdoor unit heat exchanger and an outdoor unit electronic expansion valve, characterized in that: the low temperature air conditioning heat pump system further comprises a saturated refrigerant for replenishing the intermediate pressure A compressor air supply system of the gas, the compressor air supply system being respectively connected to the four-way valve and the outdoor electronic expansion valve.  2. The low temperature air conditioning heat pump system according to claim 1, wherein: the compressor air supply system comprises a liquid reservoir, a solenoid valve, an electronic expansion valve, and a compressor provided with a gas supply port; The device is respectively connected with a solenoid valve and an electronic expansion valve, and the air inlet of the compressor is connected with the electromagnetic valve.  3. The low temperature air conditioning heat pump system according to claim 2, wherein: said compressor air supply system further comprises two temperature sensing packages, including first measuring a temperature value between said electromagnetic valve and said compressor a temperature sensing package (20), and a second temperature sensing package (21) for measuring a temperature value between the electronic expansion valve and the reservoir.  4. The low temperature air conditioning heat pump system according to claim 3, wherein: said temperature sensing package is a thermistor.  The low-temperature air-conditioning heat pump system according to claim 3, wherein: the liquid reservoir is connected to the electromagnetic valve and the electronic expansion valve by a metal pipe, and the compressor and the electromagnetic valve are utilized. a metal tube is connected, the first temperature sensing package is placed on a surface of the metal tube connecting the compressor and the electromagnetic valve, and the second temperature sensing package is placed to connect the liquid reservoir with the electronic expansion The metal tube surface of the valve. 6. The cryogenic air conditioning heat pump system according to claim 1, wherein: said compressor is a jet-enhanced digital scroll compressor. 7. The cryogenic air conditioning heat pump system according to claim 2, further comprising: a gas-liquid separator and a sub-cooling coil; wherein the gas-liquid separator is connected between the four-way valve and the compressor The secondary cooling coil is connected between the outdoor electronic expansion and the reservoir.  8. A method for reducing temperature regulation fluctuations of an air conditioning heat pump system, comprising: the following steps:  Step 1: Configure the compressor air supply system;  Step 2: Replenish the intermediate pressure saturated refrigerant gas through the compressor air supply system.  9. The method according to claim 8, wherein: in the first step: first preparing a compressor with a gas supply port, a solenoid valve, an electronic expansion valve, and a reservoir; and then connecting through a copper tube One end of the electromagnetic valve is connected to the air inlet of the compressor, and the other end of the electromagnetic valve is connected to the accumulator. The compressor is connected to the outdoor heat exchanger through a four-way valve and a gas-liquid separator. Then, one end of the electronic expansion valve is connected to the accumulator through a copper tube, and the other end of the electronic expansion valve is connected to the indoor unit heat exchange system.  10. The method according to claim 9, wherein: in the first step, a first temperature sensing package is further placed on the surface of the metal tube to which the compressor and the solenoid valve are connected, Depositing a second temperature sensing package on the surface of the metal tube connected to the electronic expansion valve;  In the second step: first setting a target superheat degree; then: subtracting the temperature values measured by the first temperature sensing packet and the second temperature sensing packet to obtain a first temperature difference; and then: using the above The subtraction of a temperature difference from the target superheat degree results in a second temperature difference, and the opening of the electronic expansion valve is controlled to achieve a saturated refrigerant gas supplementing the intermediate pressure.  11. The method of claim 10 wherein said temperature sensing package is a thermistor; said compressor being a jet enhanced digital scroll compressor.