Anti-slugging control method and control apparatus for air-conditioning system, and air-conditioning system

Abstract

An anti-slugging control method and control apparatus for an air-conditioning system. The control method includes obtaining a discharge superheat DSH of a compressor in real time, and monitoring the DSH during operation of the air-conditioning system (S 10 ); controlling a timer to start timing if the DSH is less than a first preset value M1 continuously for a first preset time t1, and controlling an outdoor unit of the air-conditioning system to stop to prevent slugging from occurring in the compressor when a measured time t of the timer reaches a second preset time t2. The DSH in the air-conditioning system is monitored in real time, such that a refrigerant drawn back to an air return port of the compressor can be ensured to be in a completely gaseous state, thereby preventing a liquid refrigerant from entering the compressor and preventing slugging. In addition, because a value of the discharge superheat is relatively large, it is convenient to inspect and control data, thereby improving the precision of anti-slugging control, and operating safety and reliability of the air-conditioning system.

What is claimed is: 
     
         1 . A control method for preventing an air conditioning system from liquid-slugging, comprising:
 acquiring an drain superheat degree of a compressor in real time, and monitoring the drain superheat degree during an operating process of the air conditioning system;   when the drain superheat degree is less than a first preset value for a first preset time period, controlling a timer to start timing; and   when a counted time period of the timer reaches a second preset time period, controlling an outdoor unit of the air conditioning system to shut down for preventing the compressor from the liquid-slugging.   
     
     
         2 . The control method according to  claim 1 , wherein during a timing process of the timer, when the drain superheat degree is greater than or equal to the first preset value for a third preset time period, resetting the timer and continuing to determine whether the drain superheat degree satisfies a condition that the timer starts timing. 
     
     
         3 . The control method according to  claim 1 , after controlling the outdoor unit to shut down, further comprising: determining whether a number of anti-liquid-slugging protection activated by the air conditioning system during a fourth preset time period exceeds a preset number, wherein,
 while the number of the anti-liquid-slugging protection activated by the air conditioning system during the fourth preset time period exceeds the preset number, controlling the outdoor unit to be unrecoverable without being powered off; and   while the number of the anti-liquid-slugging protection activated by the air conditioning system during the fourth preset time period does not exceed the preset number, resetting the timer, and controlling the outdoor unit to restart after a fifth preset time period.   
     
     
         4 . The control method according to  claim 1 , wherein the air conditioning system comprises the compressor, a condenser and an evaporator, and acquiring the drain superheat degree of the compressor in real time comprises:
 detecting temperature of an air outlet of the compressor, and detecting temperature of a middle part of the condenser and temperature of a middle part of the evaporator;   when the air conditioning system is in a refrigerating mode, calculating the drain superheat degree of the compressor according to the temperature of the air outlet and the temperature of the middle part of the condenser; and   when the air conditioning system is in a heating mode, calculating the drain superheat degree of the compressor according to the temperature of the air outlet and the temperature of the middle part of the evaporator.   
     
     
         5 . The control method according to  claim 1 , wherein acquiring the drain superheat degree of the compressor in real time comprises:
 detecting a pressure of an air outlet of the compressor and detecting temperature of the air outlet of the compressor; and   calculating the drain superheat degree of the compressor according to the pressure of the air outlet and the temperature of the air outlet.   
     
     
         6 . The control method according to  claim 3 , wherein the first preset time period is 20 minutes, the second preset time period is 30 minutes, the third preset time period is 5 minutes, the fourth preset time period is 120 minutes, and the fifth preset time period is 6 minutes. 
     
     
         7 . A non-transitory computer readable storage medium, having computer programs stored thereon, wherein when the computer programs are executed by a processor, a control method for preventing an air conditioning system from liquid-slugging according to  claim 1  is implemented. 
     
     
         8 . A control device for preventing an air conditioning system from liquid-slugging, comprising:
 an acquiring device, configured to acquire a drain superheat degree of a compressor in real time;   a monitoring device, configured to monitor the drain superheat degree during an operating process of the air conditioning system;   a control device, configured to, when the drain superheat degree is less than a first preset value for a first preset time period, control a timer to start timing; and when a counted time period of the timer reaches a second preset time period, control an outdoor unit of the air conditioning system to shut down for preventing the compressor from the liquid-slugging.   
     
     
         9 . The control device according to  claim 8 , wherein during a timing process of the timer, when the drain superheat degree is greater than or equal to the first preset value for a third preset time period, the control device is configured to reset the timer and continue to determine whether the drain superheat degree satisfies a condition that the timer starts timing. 
     
     
         10 . The control method according to  claim 8 , wherein after the outdoor unit is controlled to shut down, the control device is further configured to determine whether a number of anti-liquid-slugging protection activated by the air conditioning system during a fourth preset time period exceeds a preset number, wherein,
 while the number of the anti-liquid-slugging protection activated by the air conditioning system during the fourth preset time period exceeds the preset number, the control device is configured to control the outdoor unit to be unrecoverable without being powered off; and   while the number of the anti-liquid-slugging protection activated by the air conditioning system during the fourth preset time period does not exceed the preset number, the control device is configured to reset the timer, and control the outdoor unit to restart after a fifth preset time period.   
     
     
         11 . The control device according to  claim 8 , wherein the air conditioning system comprises the compressor, a condenser and an evaporator, and the control device further comprises:
 a first temperature sensor arranged at an air outlet of the compressor and configured to detect temperature of the air outlet of the compressor;   a second temperature sensor arranged at a middle part of the condenser and configured to detect temperature of the middle part of the condenser; and   a third temperature sensor arranged at a middle part of the evaporator and configured to detect temperature of the middle part of the evaporator;   wherein the acquiring device is further configured to calculate the drain superheat degree of the compressor according to the temperature of the air outlet and the temperature of the middle part of the condenser when the air conditioning system is in a refrigerating mode; and to calculate the drain superheat degree of the compressor according to the temperature of the air outlet and the temperature of the middle part of the evaporator when the air conditioning system is in a heating mode.   
     
     
         12 . The control device according to  claim 8 , further comprising a fourth temperature sensor and a pressure sensor arranged at an air outlet of the compressor, wherein the fourth temperature sensor is configured to detect temperature of the air outlet of the compressor and the pressure sensor is configured to detect pressure of the air outlet of the compressor, and the acquiring device is configured to calculate the drain superheat degree of the compressor according to the temperature of the air outlet and the pressure of the air outlet. 
     
     
         13 . The control device according to  claim 10 , wherein the first preset time period is 20 minutes, the second preset time period is 30 minutes, the third preset time period is 5 minutes, the fourth preset time period is 120 minutes, and the fifth preset time period is 6 minutes. 
     
     
         14 . An air conditioning system, comprising:
 a control device for preventing an air conditioning system from liquid-slugging, comprising:   an acquiring device, configured to acquire a drain superheat degree of a compressor in real time;   a monitoring device, configured to monitor the drain superheat degree during an operating process of the air conditioning system;   a control device, configured to, when the drain superheat degree is less than a first preset value for a first preset time period, control a timer to start timing; and when a counted time period of the timer reaches a second preset time period, control an outdoor unit of the air conditioning system to shut down for preventing the compressor from the liquid-slugging.