A CONTROL SYSTEM FOR AN ELECTRONIC EXPANSION VALVE IN A REFRIGERATION SYSTEM

摘要

A control system for an electronic expansion valve (10) in a refrigeration system (5) is discosed. The electronic expansion valve (10) incrementally controls refrigerant flow between a condenser (13) and an evaporator (11) of the refrigeration system (5). The electronic expansion valve (10) is operated by a digitally controllable electric motor (24) which incrementally adjusts the position of the electronic expansion valve (10) in response to electronic digital control signals supplied to the motor (24) from a microcomputer control system (23). The microcomputer control system (23) supplies the electronic digital control signals to the motor (24) in a preprogrammed manner in response to selected sensed operating conditions of the refrigeration system. Preferably, the electronic expansion valve (10) is controlled in response to superheat of refrigerant vapor flowing from the evaportor (11) to a compressor (12) of the refrigeration system (5).