According to the different working principle, air conditioning compressors can be divided into fixed displacement compressor and variable displacement compressor.
Displacement compressor displacement as the engine speed increases in proportion to the increase, it can not be based on cooling demand to automatically change the power output, but also on the engine fuel consumption greater impact. Its control is generally collected by the evaporator outlet temperature signal, when the temperature reaches the set temperature, the compressor electromagnetic clutch is released, the compressor stops working. When the temperature rises, the electromagnetic clutch is engaged and the compressor starts to work. Constant displacement compressor is also subject to the pressure control of air conditioning system, when the pressure inside the pipeline is too high, the compressor stops working.
Variable displacement compressor can automatically adjust the power output according to the set temperature. Air conditioning control system does not collect the evaporator outlet temperature signal, but according to air conditioning pipe pressure changes in the signal control of the compressor compression ratio to automatically adjust the outlet temperature. In the whole process of refrigeration, the compressor is always working, and the adjustment of refrigeration intensity depends entirely on the pressure regulating valve installed inside the compressor. When the air conditioning piping pressure is high at the high end, the pressure regulating valve to shorten the piston stroke in the compressor to reduce the compression ratio, thus reducing the cooling intensity. When the high-pressure end pressure drops to a certain extent, low-pressure end pressure rises to a certain extent, the pressure control valve is to increase the piston stroke to improve the cooling intensity.
Variable displacement compressor can automatically adjust the power output according to the set temperature. Air conditioning control system does not collect the evaporator outlet temperature signal, but according to air conditioning pipe pressure changes in the signal control of the compressor compression ratio to automatically adjust the outlet temperature. In the whole process of refrigeration, the compressor is always working, and the adjustment of refrigeration intensity depends entirely on the pressure regulating valve installed inside the compressor. When the air conditioning piping pressure is high at the high end, the pressure regulating valve to shorten the piston stroke in the compressor to reduce the compression ratio, thus reducing the cooling intensity. When the high-pressure end pressure drops to a certain extent, low-pressure end pressure rises to a certain extent, the pressure control valve is to increase the piston stroke to improve the cooling intensity.