Classification of working principle of automotive air conditioning compressor
According to different working principles, air-conditioning compressors can be divided into fixed displacement compressors and variable displacement compressors.
Fixed displacement compressor
The displacement of the fixed displacement compressor is proportional to the increase of the engine speed. It can not automatically change the power output according to the cooling demand, and has a greater impact on the engine fuel consumption. Its control generally collects the temperature signal of the evaporator outlet. When the temperature reaches the set temperature, the compressor electromagnetic clutch is released and the compressor stops working. When the temperature rises, the electromagnetic clutch is combined and the compressor starts to work. The fixed displacement compressor is also controlled by the pressure of the air conditioning system. When the pressure in the pipeline is too high, the compressor stops working.
Variable displacement air conditioner compressor
The variable displacement compressor automatically adjusts the power output based on the set temperature. The air conditioning control system does not collect the temperature signal of the evaporator outlet, but automatically adjusts the outlet temperature according to the pressure change signal in the air conditioning pipeline to automatically adjust the outlet temperature. In the whole process of refrigeration, the compressor is always working, and the adjustment of the cooling intensity is completely controlled by the pressure regulating valve installed inside the compressor. When the pressure at the high pressure end of the air conditioning line is too high, the pressure regulating valve shortens the piston stroke in the compressor to reduce the compression ratio, which reduces the cooling strength. When the pressure at the high pressure end drops to a certain extent and the pressure at the low pressure end rises to a certain extent, the pressure regulating valve increases the stroke of the piston to increase the cooling strength.