An effective optimized strategy on speed fluctuation suppression for air conditioner compressor

Aiming at the problem of existing larger speed fluctuation when the variable frequency air conditioning compressor running at low frequency, the reason of speed fluctuation in the low speed range for compressor is analyzed thoroughly in this paper, a speed fluctuation suppression strategy for the air conditioning compressor is proposed. Firstly, the periodic speed pulsation of compressor is reduced by P-type iterative learning control (PILC), and a forgetting factor is introduced into the PILC algorithm for weakening the error accumulation of non-periodic disturbance, then, the modified ILC algorithm is optimized for reducing the speed fluctuation suppression effect further. Afterwards, a feed-forward is performed by the q-axis current compensation of PILC, which is to realize the torque compensation of compressor torque. Thereby, the purpose of suppressing speed fluctuation is achieved. Finally, simulations are implemented on Matlab/Simulink platform, and experimental researches are implemented on the H&T variable frequency air conditioner compressor control system. The research results indicate that the proposed strategy can effectively suppress the speed fluctuation of compressor at low frequency.