基于载波移相大功率并联逆变器输出谐波分析

The Harmonic Analysis of a Large Capacity Parallel Inverter with Carrier Phase-shifted PWM

以超导托卡马克核聚变实验装置(EAST)中的快控电源为背景,研究分析了采用载波移相PWM技术实现逆变器并联输出的系统设计方案,并利用双重傅里叶变换对逆变器并联输出谐波进行分析,建立其数学模型。仿真和实验表明,采用载波移相PWM技术实现逆变器并联输出可以消除低次谐波,提高等效开关频率,对实现电源系统大电流输出与快速响应具有良好效果。

Based on the fast control power system of experimental advanced superconducting Tokamak （EAST） project, the paper studies the power system design scheme which adopts the multiple parallel connected structure of carrier phase-shifted PWM inverter,and the output harmonic characteristic of parallel inverter by means of dual Fourier transformation ,the mathematical model is set up.The simulation and experimental results confirm that the technique of carrier phase-shifted PWM used in the multiple parallel inverter has many merits ,such as decreasing low-order harmonics, raising equal switch-frequency of inverter, and making the system supply large current and having ability of fast response.