Digital control of VRF multisplit systems

摘要

On the basis of the load depending driving power of a hermetic compressor it is obvious to achieve a partial load control either by the change of the motor speed or the motor torque. In both cases one achieves a load depending change of the driving power, that means the implementation of the VRF principle. On this basis world-wide two technologies became generally accepted: widespread speed control by means of frequency converter and the torque control for rolling piston compressors.