Gas-replenishing and enthalpy-increasing control method, device and apparatus for two-stage compressor

Patent metadata

Field	Value
Publication number	US-2018356136-A1
Application number	US-201615775476-A
Country	US
Kind code	A1
Filing date	May 5, 2016
Priority date	Dec 11, 2015
Publication date	Dec 13, 2018
Grant date	—

Abstract

Provided are a gas-replenishing and enthalpy-increasing control method, device and apparatus for a two-stage compressor. The method includes: when a gas-replenishing electronic expansion valve needs to be opened, gradually increasing, by a controller, an opening degree of the gas-replenishing electronic expansion valve in a time sequence; after the gas-replenishing electronic expansion valve is opened, acquiring a detected gas-replenishing superheat degree of a two-stage compressor; and adjusting, based on the gas-replenishing superheat degree of the two-stage compressor, the opening degree of the gas-replenishing electronic expansion valve, wherein the gas-replenishing electronic expansion valve is disposed between a medium-pressure liquid storage tank and the two-stage compressor, and when the opening degree of the gas-replenishing electronic expansion valve is not zero, a gaseous refrigerant in the medium-pressure liquid storage tank replenishes gas and increases enthalpy for the two-stage compressor,.

First claim

1 . A gas-replenishing and enthalpy-increasing control method for a two-stage compressor, comprising:
when a gas-replenishing electronic expansion valve needs to be opened, gradually increasing, by a controller, an opening degree of the gas-replenishing electronic expansion valve in a time sequence; after the gas-replenishing electronic expansion valve is opened, acquiring a detected gas-replenishing superheat degree of a two-stage compressor; and adjusting, based on the gas-replenishing superheat degree of the two-stage compressor, the opening degree of the gas-replenishing electronic expansion valve, wherein the gas-replenishing electronic expansion valve is disposed between a medium-pressure liquid storage tank and the two-stage compressor, and when the opening degree of the gas-replenishing electronic expansion valve is not zero, a gaseous refrigerant in the medium-pressure liquid storage tank replenishes gas and increases enthalpy for the two-stage compressor.

2 . The method as claimed in claim 1 , wherein gradually increasing, by a controller, an opening degree of the gas-replenishing electronic expansion valve in a time sequence when a gas-replenishing electronic expansion valve needs to be opened comprises:
after the two-stage compressor is opened and operates for a first preset time period, controlling, by the controller, the opening degree of the gas-replenishing electronic expansion valve to be a first preset opening degree; when the opening degree of the gas-replenishing electronic expansion valve is the first preset opening degree, after the gas-replenishing expansion valve operates for a second preset time period, increasing the opening degree of the gas-replenishing electronic expansion valve to a second preset opening degree; and when the opening degree of the gas-replenishing electronic expansion valve is a second preset opening degree, after the gas-replenishing expansion valve operates for a third preset time period, fully opening the gas-replenishing electronic expansion valve.

3 . The method as claimed in claim 1 , wherein acquiring a detected gas-replenishing superheat degree of a two-stage compressor comprises:
collecting a gas-replenishing temperature and a gas-replenishing pressure of the two-stage compressor; acquiring a saturation temperature corresponding to the gas-replenishing pressure; and taking a difference between the gas-replenishing temperature and the saturation temperature as the gas-replenishing superheat degree of the two-stage compressor.

4 . The method as claimed in claim 3 , wherein adjusting, based on the gas-replenishing superheat degree of the two-stage compressor, the opening degree of the gas-replenishing electronic expansion valve comprises:
judging whether the gas-replenishing superheat degree of the two-stage compressor is greater than a preset superheat degree at predetermined intervals; when the gas-replenishing superheat degree of the two-stage compressor is greater than the preset superheat degree, determining that the replenished gas of the two-stage compressor entrains liquid; when the gas-replenishing superheat degree of the two-stage compressor is not greater than the preset superheat degree, determining that the replenished gas of the two-stage compressor does not entrain liquid; and adjusting the opening degree of the gas-replenishing electronic expansion valve according to the situation that the replenished gas of the two-stage compressor entrains liquid.

5 . The as claimed in claim 4 , wherein adjusting the opening degree of the gas-replenishing electronic expansion valve according to the situation that the replenished gas of the two-stage compressor entrains liquid comprises:
when the replenished gas of the two-stage compressor entrains liquid, reducing the current opening degree of the gas-replenishing electronic expansion valve to a preset opening degree, wherein the preset opening degree is an opening degree preset based on a full opening degree of the gas-replenishing electronic expansion valve, and the full opening degree is an opening degree when the gas-replenishing electronic expansion valve is fully opened; and when the replenished gas of the two-stage compressor does not entrain liquid, keeping the current opening degree of the gas-replenishing electronic expansion valve unchanged or increasing the current opening degree.

6 . The method as claimed in claim 5 , wherein keeping the current opening degree of the gas-replenishing electronic expansion valve unchanged or increasing the current opening degree comprises:
when it is determined that the replenished gas of the two-stage compressor does not entrain liquid, if the operations of reducing the current opening degree of the gas-replenishing electronic expansion valve and keeping the current opening degree of the gas-replenishing electronic expansion valve are executed respectively after it was judged previously twice whether the gas-replenishing superheat degree is greater than the preset opening degrees, executing the operation of increasing the current opening degree of the gas-replenishing electronic expansion valve, and otherwise, executing the operation of keeping the current opening degree of the gas-replenishing electronic expansion valve.

7 . A gas-replenishing and enthalpy-increasing control device for a two-stage compressor, comprising:
a gas-replenishing electronic expansion valve, disposed between a medium-pressure liquid storage tank and a two-stage compressor; and a controller, connected to the gas-replenishing electronic expansion valve, and configured to gradually increase an opening degree of the gas-replenishing electronic expansion valve in a time sequence when the gas-replenishing electronic expansion valve needs to be opened, acquire a gas-replenishing superheat degree of the two-stage compressor after the gas-replenishing electronic expansion valve is opened, and adjust the opening degree of the gas-replenishing electronic expansion valve based on the gas-replenishing superheat degree of the two-stage compressor.

8 . The device as claimed in claim 7 , further comprising:
a detection apparatus, connected to the controller, and configured to collect a gas-replenishing temperature and a gas-replenishing pressure of the two-stage compressor, wherein the controller comprises: a reading apparatus, connected to the detection apparatus, and configured to read a saturation temperature corresponding to the gas-replenishing pressure; and a calculator, connected to the detection apparatus and the reading apparatus, and configured to calculate a difference between the gas-replenishing temperature and the saturation temperature, so as to obtain the gas-replenishing superheat degree.

9 . The device as claimed in claim 8 , wherein the detection apparatus further comprises:
a pressure sensor, disposed at a gas-replenishing port of the two-stage compressor, and configured to collect the gas-replenishing pressure; and a temperature-sensing package, disposed at the gas-replenishing port of the two-stage compressor, and configured to collect the gas-replenishing temperature.

10 . The device as claimed in claim 7 , further comprising:
a four-way valve, a first end being connected to the two-stage compressor; a gas-liquid separator, a first end being connected to a second end of the four-way valve, and a second end being connected to the two-stage compressor; an outdoor heat exchanger, a first end being connected to a third end of the four-way valve; and an indoor heat exchanger, a first end being connected to a fourth end of the four-way valve, and a second end being connected to the medium-pressure liquid storage tank.

11 . The de

Assignees

• Gree Electric Appliances Inc Zhuhai

Inventors

• Zhao Huan
• Shen Jun
• Tan Feng
• Liang Youxuan
• Li Pengfei

Classifications

• F25B2600/2513

  Expansion valves · CPC title

• F25B2700/1933

  Suction pressures · CPC title

• F25B2600/01

  Timing · CPC title

• F25B2700/21151

  at the suction side of the compressor · CPC title

• F25B2700/21152

  at the discharge side of the compressor · CPC title