A THD Optimization Control for High frequency Full-SiC PWM Rectifier based on Multi-resolution Algorithm

Abstract

A multi-resolution control algorithm is adopted to minimize the negative effect caused by digital control delay to lower the total harmonic distortion (THD) of high frequency PWM rectifiers for aviation applications. The influence of digital control delay is analyzed first. The algorithm makes the best use of the limited digital signal processor (DSP) resources to increase the control frequency of the tasks that mainly affect the rectifier’s performance by executing the left tasks at a relatively low frequency. A 5kW prototype with full SiC devices is built to verify the effectiveness and advantages of the proposed algorithm and good experimental results have been obtained.