Method for controlling evaporation temperature in a multi-evaporator refrigeration system

Abstract

A method for controlling a temperature-related refrigeration parameter of parallel evaporators of an evaporation stage of a refrigeration system within an operational range of the refrigeration parameter for the evaporators, with a control valve positioned between the evaporators and a compression stage in the refrigeration system to vary a suction effect of the compression stage on the evaporation stage and a sensors associated with each of the evaporators. The method comprises the steps of monitoring the temperature-related refrigeration parameter for each evaporator individually with their respective sensors; and modulating the control valve to vary the suction effect of the compression stage on the evaporators of the evaporator stage, as a response to a signal from any sensor detecting a refrigeration parameter value out of the operational range for any one of the evaporators, so as to return the refrigeration parameter value to the operational range.

1 . A method for controlling a temperature-related refrigeration parameter of at least two parallel evaporators of an evaporation stage of a refrigeration system within an operational range of the refrigeration parameter for the evaporators, with a control valve positioned between the at least two evaporators and a compression stage in the refrigeration system to vary a suction effect of the compression stage on the evaporation stage and a sensors associated with each of the evaporators, comprising the steps of: 
 monitoring the temperature-related refrigeration parameter for each one of the evaporators individually with respective ones of the sensors; and    modulating the control valve to vary the suction effect of the compression stage on the evaporators of the evaporator stage, as a response to a signal from any one of the sensors detecting a refrigeration parameter value out of said operational range for any one of the evaporators, so as to return said refrigeration parameter value to said operational range.    
     
     
         2 . The method according to  claim 1 , wherein the temperature-related refrigeration parameter is a temperature in refrigerators cooled by the evaporators of the evaporation stage.  
     
     
         3 . The method according to  claim 1 , wherein the temperature-related refrigeration parameter is a refrigerant pressure in the evaporators.  
     
     
         4 . A system for controlling a temperature-related refrigeration parameter of a first group of at least two parallel evaporators of an evaporation stage of a refrigeration system, comprising: 
 a first control valve positioned between the evaporation stage and a compression stage of the refrigeration system, the at least one control valve being modulable to vary a suction effect of the compression stage on the evaporation stage;    sensors associated with each one of the evaporators of the first group of evaporators; and    a controller having a first operational range of the refrigeration parameter for the first group of evaporators and being connected to the first control valve and to each one of the sensors, so as to monitor the refrigeration parameter of each one of the evaporators individually through respective ones of the sensors, and to modulate the first control valve as a response to a refrigeration parameter value of any one of the evaporators of the first group of evaporators being out of said first operational range so as to return said refrigeration parameter value to said first operational range.    
     
     
         5 . The system according to  claim 4 , further comprising at least a second group of evaporators and a second control valve for the second group of evaporators, with each of the evaporators of the second group of evaporators being associated with a sensor, said controller having a second operational range of the refrigeration parameter for the second group so as to modulate the second control valve as a response to a refrigeration parameter value of any one of the evaporators of the second group of evaporators being out of said second operational range so as to return said refrigeration parameter value to said second operational range, independently of a control of the first group of actuators.  
     
     
         6 . The system according to  claim 4 , wherein the temperature-related refrigeration parameter is a temperature in refrigerators cooled by the evaporators of the evaporation stage.  
     
     
         7 . The system according to  claim 4 , wherein the temperature-related refrigeration parameter is a refrigerant pressure in the evaporators.