Vibration Reduction in Rolling Piston-Type Compressors through Motor Torque Control. Basic Study on Theoretical Analysis and Computer Simulation.

Abstract

A control system to reduce vibation in rolling piston-type compressors in room air conditioners is proposed. To suppress compressor vibration due to torque excitation, a torque control system is applied. This method uses a microcomputer, which makes the motor output torque nearly equal to the load torque variation which is caused by gas compression at any angular position. Theoretical analysis and computer simulation show that the control system, in which the rotational variaion (fluctuation of angular speed or angular acceleration) is caused by the torque difference, is detected during one revolution and is reflected to the motor output torque at the next revolution, due to the cyclic characteristic of the load torque. This shows that repetitive control, can be adopted. Thus, reduction of compressor vibration is possible.