Practical Fuzzy Repetitive Control for Accurate Amplitude and Phase Tracking in Linear Compressor

Linear compressor is a kind of novel gas pumping equipment used in refrigeration applications. Compared with conventional rotary compressor, it has the benefits of high efficiency, low noise, and less discharge pollution, which coincides with green energy strategy worldwide. As the core component in linear compressor, linear actuator provides the energy for gas pumping. Thus, its output amplitude and frequency affect system performance significantly. However, influenced by complex load of linear compressor, such as friction, gas pressure, spring elastic load, etc., the control performance of linear actuator suffers from severe amplitude decline and phase lag in high frequency tracking mode. In order to deal with this problem, a practical fuzzy repetitive controller is proposed for high frequency amplitude and phase tracking in linear compressor. Actuator modeling and controller analysis are conducted in details, and then simulation is carried out for validation. The results show that the proposed fuzzy repetitive controller works well with system and enhances working performance obviously.