Abstract: This paper summarizes the research on heating power of defrosting heater in air-cooled refrigerators by Chinese scholars, and puts forward a theory that the input voltage of defrosting heater is stabilized to a certain constant value by setting a voltage stabilized power supply on the control board and chopping off the voltage waveform, thus realizing the constant power output of defrosting heater. Two prototypes were fabricated and the power voltage gradient was tested. The results show that the power fluctuation rate of the defrosting heater is stable in the range of ±5% of the target power, and the constant power output of the defrosting heater is realized.

Key words: Defrosting heater, Control board, Constant power