Method for controlling level of liquid within an evaporator and a system thereof

A method of controlling a level of liquid within an evaporator of a flooded-type chiller without level sensors, the flooded-type chiller including at least one compressor, a condenser, expansion valve and an evaporator being arranged in series, the method comprising:

• measuring a plurality of first group of parameters using a plurality of sensors positioned in the flooded-type chiller;
• calculating a plurality of second group of parameters using the measured value of the first group of parameters by a controller having at least one processor, wherein the processor is in communication with said plurality of sensors;
• determining a virtual refrigerant level as a control signal based on the second group of parameter values by the controller;
• and
• controlling a desired refrigerant level in the evaporator by controlling operation of said expansion valve based on said determined virtual refrigerant level with respect to a dead zone for maintaining a pre-defined target refrigerant level;
• wherein when a suction pressure reduces and reaches a pre-defined low suction pressure setpoint, said controller invokes said control signal to open said expansion valve, till said suction pressure is more than said pre-defined low suction pressure setpoint.

A method of controlling a level of liquid within an evaporator of a flooded-type chiller without level sensors, the flooded-type chiller including at least one compressor, a condenser, expansion valve and an evaporator being arranged in series, the method comprising:

• measuring a plurality of first group of parameters using a plurality of sensors positioned in the flooded-type chiller;
• calculating a plurality of second group of parameters using the measured value of the first group of parameters by a controller having at least one processor, wherein the processor is in communication with said plurality of sensors;
• determining a virtual refrigerant level as a control signal based on the second group of parameter values by the controller;
• and
• controlling a desired refrigerant level in the evaporator by controlling operation of said expansion valve based on said determined virtual refrigerant level with respect to a dead zone for maintaining a pre-defined target refrigerant level;
• wherein said first group of parameters include suction pressure, discharge pressure, leaving water temperature, discharge temperature and electric current.