CONTROL METHOD AND DEVICE FOR ELECTRONIC EXPANSION VALVE AND REFRIGERATING UNIT Russian patent published in 2021 - IPC F25B41/06 F25B49/02 

FIELD: electrical engineering.

SUBSTANCE: invention discloses a control method and a device for an electronic expansion valve and a refrigerating unit. Step 1 involves obtaining temperature difference Tp at the end of the evaporator. Step 2 includes comparing the temperature difference Tp with the control setting Ts for the temperature difference at the end of the evaporator to obtain a difference ΔTp between temperature difference Tp and control setting Ts. At that, Ts = Pinch_SP + Pdt, where Pinch_SP is the preset value of the setting for the temperature difference at the evaporator end, and Pdt is the value of dynamic correction. Stage 3 includes determination of required degree of opening of electronic expansion valve in accordance with relationship between difference ΔTr and specified deviation value. Stage 4 includes control of opening degree of electronic expansion valve for its adjustment to required degree of opening. If difference ΔTp between these two values is more than the allowable deviation, then the valve opening degree will be increased, and if the difference is less than the allowable deviation, then the valve opening degree will be reduced. Changes in the degree of opening of the electronic expansion valve can be controlled, which enables to supply the most suitable amount of liquid into the evaporator and minimizes the temperature difference Tp between the heat exchange ends of the evaporator.

EFFECT: technical result is complete use of heat exchange characteristics of evaporator.

15 cl, 5 dwg