Deadbeat Predictive Current Control Based on Accurate Discrete Luenberger Observer for PMSM under Low Frequency Ratio

Abstract

Aiming at the problems of discrete truncation error and parameter sensitivity of traditional deadbeat predictive current control under low frequency ratio, a deadbeat predictive current control based on accurate discrete Luenberger observer for permanent magnet synchronous motor is proposed. In order to eliminate the angle delay caused by coordinate transformation, an accurate discrete model of permanent magnet synchronous motor is established in the $\alpha\beta$-axes. On this basis, an accurate model deadbeat predictive current control is designed. At the same time, in order to suppress the steady-state error of deadbeat predictive current control caused by parameter mismatch, an accurate discrete Luenberger observer is embedded in the deadbeat predictive current control, which directly designs the parameters of the Luenberger observer in the discrete domain, and analyzes the stability of the accurate discrete Luenberger observer. Finally, the effectiveness of the proposed method is verified on a 2.1 kW permanent magnet synchronous motor experimental platform.