Two-Step Deadbeat Predictive Current Control of PMSM Drives with Reduced Time Delay

A high-performance permanent magnet synchronous motor control system necessitates a fast-responding current inner loop to ensure the system's high dynamic capability. Traditional PI control with limited bandwidth constrains the dynamic response speed, while deadbeat predictive current control (DPCC) exhibits superior dynamic response. However, the presence of a one-step delay in digital control systems degrades control performance and stability. Traditional deadbeat current prediction control entails a two-step trailing effect. To further enhance the dynamic performance of the current loop, a two-step prediction current control algorithm with an improved timing scheme in the stationary coordinate system has been developed and illustrated in this paper. The proposed method samples current at the midpoint of one carrier wave, updates modulation waveforms at the start of the next carrier wave, and eliminates current tracking error value at the midpoint of the next sampling. With such timing configuration, it necessitates the separate computation of voltage vectors for the first half and the second half of the carrier wave period, which requires two-step predictions. This two-step current prediction control algorithm reduces the current control delay from two control cycles to one control cycle. Simulation and experimental results demonstrate that compared to conventional deadbeat prediction current control, the improved timing two-step prediction control algorithm effectively enhances the dynamic performance of the current loop.