用于改善直流链电流纹波的电流源型整流器扇区优化调制策略

Optimized Sector Modulation Strategy of Current Source Rectifier for DC-Link Current Ripple Reduction

电流源型整流器采用十二扇区空间矢量脉宽调制(SVPWM)可缩短器件换流过程并减小开关损耗,但整流器在运行时直流链电流纹波较大,而采用增大电感值的方法抑制电流纹波会增大电感的损耗和体积,影响系统整体运行性能。为此,该文首先提出一种适用于宽范围运行情况下直流链电流纹波的优化调制策略。其次,基于十二扇区实现机理和电感电流纹波产生原理,通过所提出的电流纹波分析模型推导分析电流纹波表达式,并深入对比分析两种调制策略的直流链电流纹波峰值分布规律。最后,通过仿真和实验样机验证了理论分析的正确性和调制策略的有效性。

Twelve sector space vector pulse width modulation(SVPWM)can shorten the commutation process and reduce the switching loss of current source rectifier.However,the DC link current ripple is large when the rectifier is in operation.The DC link current ripple can be reduced by increasing the inductance,but the inductance loss and size will increase accordingly,affecting the overall operation performance of the system.Therefore,this paper proposes an optimized modulation strategy for DC link current ripple in wide range operation.Secondly,based on the twelve-sector implementation mechanism and inductor current ripple generation principle,the current ripple expression is deduced and analyzed through the proposed current ripple analysis model,and the peak distribution of DC link current ripple of the two modulation strategies is compared and analyzed.Finally,the theoretical analysis and the effectiveness of the proposed method are verified through simulation and experimental prototype.