Research on error self‐correction complementary non‐zero vector pulse width modulation strategy

Abstract

The DC link single sensor phase current reconstruction method has brought several challenges, which consist of the unobservable area and current zero drift error, where the duration of the effective vector is too short to measure, and current zero drift error leads to reconstruction error. An error self-correction complementary non-zero vector pulse width modulation (ESC 2 N-PWM) method is proposed. Through the analysis of the DC link sampling principle, the minimum sample time is defined. Then applying complementary non-zero vectors to replace zero voltage vector, the current sampling window is extended, and the sector boundary unobservable area is eliminated. At the same time, through the dynamic double sampling of the complementary effective voltage vectors, the zero drift of current is self-detected and self-corrected. The experimental results show that the reconstruction error of the proposed method is lower than 2.84%, and the current THD is lower than 6.20%.