Cooling system

Abstract

A cooling system includes: a compressor; a condenser; an expansion valve; an evaporator; an internal heat exchanger having a first conduit in heat exchanging contact with a second conduit, the first conduit being part of a high pressure fluid line between the condenser and the expansion valve, the second conduit being part of a low pressure fluid line between the evaporator and the compressor; a bypass line connecting the high pressure fluid line with the low pressure fluid line and for injecting small amounts of liquid fluid from the high pressure fluid line into the low pressure fluid line; a valve arranged in the bypass line for opening and closing the bypass line; and a control device for monitoring a load point of the compressor and controlling the valve to an open position when the load point exceeds a threshold.

1 . A cooling system, comprising:
 connected in a loop in succession, a compressor;   a condenser;   an expansion valve; and   an evaporator;   an internal heat exchanger having a first conduit in heat exchanging contact with a second conduit, the first conduit being part of a high pressure fluid line between the condenser and the expansion valve, the second conduit being part of a low pressure fluid line between the evaporator and the compressor;   a bypass line connecting the high pressure fluid line with the low pressure fluid line and being configured to inject small amounts of liquid fluid from the high pressure fluid line into the low pressure fluid line;   a valve arranged in the bypass line and configured to open and close the bypass line; and   a control device configured to monitor a load point of the compressor and to control the valve to an open position when the load point exceeds a threshold.   
     
     
         2 . The cooling system according to  claim 1 , wherein the bypass line is arranged in the internal heat exchanger between the first conduit and the second conduit. 
     
     
         3 . The cooling system according to  claim 1 , further comprising a temperature sensor and/or a pressure sensor connected to the control device and arranged in the low pressure fluid line. 
     
     
         4 . The cooling system according to  claim 1 , wherein the valve comprises a back pressure valve or a thermostat valve having the respective sensor in fluid connection with the low pressure fluid line. 
     
     
         5 . A method for controlling the cooling system according to  claim 1 , which method comprises:
 while having the bypass line closed, monitoring the load point of the compressor; and   when the monitored load point exceeds a threshold, shortly opening the bypass line by controlling the valve, to inject an amount of liquid from the high pressure fluid line into the low pressure fluid line.   
     
     
         6 . The method according to  claim 5 , wherein the load point of the compressor is monitored by a temperature of a fluid entering the compressor. 
     
     
         7 . The method according to  claim 5 , wherein the load point of the compressor is monitored by a pressure of a fluid entering the compressor. 
     
     
         8 . The cooling system according to  claim 3 , wherein the temperature sensor and/or pressure sensor is arranged in the low pressure fluid line near the compressor. 
     
     
         9 . The method according to  claim 6 , wherein the load point of the compressor is monitored by a pressure of the fluid entering the compressor.