Principle of Refrigeration Lighting Circuit in Electrolux Refrigerator

When the power supply is turned on, the computer chip starts to work, the DC voltage of the main circuit of the frequency converter rises, and the electronic thermostat takes the temperature signal as the feedback signal of the frequency converter. Because the temperature in the refrigerator is high before operation, it is quite different from the set temperature. When the DC voltage of the inverter main circuit rises to the rated value, the computer chip sends a start signal to the inverter after time delay, and the inverter starts to run, and the output frequency gradually rises. At the same time, the compressor started to run, and the speed gradually increased.

At this time, the temperature of the refrigerator is quite different from the set temperature, the output frequency of the inverter rises to the maximum, the compressor runs at high speed, the refrigerator is in a forced cooling state, and the temperature in the refrigerator reaches the set value in a short time. Due to inertia, the temperature in the refrigerator continues to drop below the set value. When the frequency converter output frequency decreases, the compressor speed decreases, the refrigeration capacity decreases, and the temperature in the refrigerator increases. When the temperature in the refrigerator is equal to the set temperature, the output frequency of the inverter is stable at this value, the compressor runs at a constant speed, and the refrigeration capacity remains unchanged. At this time, the refrigerator is in a constant temperature state and the compressor is in a continuous low-speed operation state.

When the refrigerator door is opened to store articles or defrost, the temperature in the refrigerator rises, the output frequency of the frequency converter rises, the operating speed of the compressor rises, and the refrigeration capacity increases, so that the refrigerator temperature returns to the set temperature and the refrigerator is in a constant temperature operation state again.

When the ambient temperature of the refrigerator rises, the heat dissipation is serious, and the temperature also rises, so the frequency converter correspondingly increases the output frequency, the compressor speed increases, the refrigeration capacity increases, and the refrigerator temperature returns to the set value and is in a constant temperature state again. On the contrary, when the ambient temperature of the refrigerator drops, the refrigerator is also in a constant temperature state after frequency conversion adjustment.

Circuit diagram of multifunctional refrigerator controller

As shown in the figure, it is the control circuit of the multifunctional refrigerator. The controller consists of overvoltage and undervoltage sampling circuit, delay start circuit, acousto-optic alarm circuit and buck rectifier circuit. Buck rectifier circuit provides DC voltage for the whole controller.