Dynamic modulation of voltage excitation angle to optimize energy consumption of refrigerator

This study presents a dynamic modulation of voltage excitation angle technology applied to a refrigerator so that the refrigerator operates at optimum energy consumption. This technique utilizes a semiconductor element, Tri-electrode AC switch (TRIAC), as a regulatory element for modulating the voltage excitation angle and the sensing current is taken as the feedback signal to determine the voltage modulation range. Thus, a novel energy saving controller (NESC) was successfully developed. We validated the feasibility of the proposed NESC; tests were performed where the door is closed for one hour and a dynamic simulation of normal use where the door is opened and closed periodically in one hour. The energy-saving rates obtained were 20.48% and 12.88%, respectively. In addition, a long period of one day tests on refrigerator was also conducted with and without NESC, and the best power consumption was measured at 6.597 kWh 24 h−1. An energy-saving rate of 22.41% was achieved.