Abstract
An evaporator superheat control system with an electrically driven expansion valve (EEV) is investigated theoretically and experimentally. Considerations between characteristic values and affecting factors of a refrigeration cycle gives a transfer function model of a prototype evaporator based on experimental results. The sampled-data PI algorism for EEV openings is employed to control the evaporator superheat.
The control system stability is analyzed and influence of the control parameters are studied. Control experimental results show that the proposed simulation model is confirmed effective to find proper control parameters.
