三相BUCK型SVPWM整流器LC振荡阻尼混合控制

为了抑制电流型PWM整流器输入侧LC滤波器谐振引起网侧电流畸变和系统振荡,提出了一种采用有源阻尼控制和改进SVPWM技术结合的控制策略。采用虚拟谐波阻尼器的有源控制策略,在控制过程中增加虚拟的等效阻尼电阻,能够在不改变基波功率流动的前提下抑制LC谐振引起的畸变和振荡。分析BUCK型PWM整流器的数学模型,比较无源阻尼和有源阻尼控制优缺点,在采用改进SVPWM的BUCK型整流器中引入有源阻尼补偿器。仿真和实验结果表明,所提出的控制方法能够有效地减小线电流畸变,改善系统稳定性,具有一定的工程实用价值。

Damping of LC oscillation using a hybrid combination approach for three-phase BUCK-type SVPWM rectifier

An effective method combining the active damping control with an improved SVPWM technology is proposed to reduce grid-side current distortion and system oscillation caused by current source PWM rectifier LC filter resonance. The virtual harmonic active damper control strategy, which adds an equivalent damping resistor, can suppress the current distortion and oscillation caused by LC resonance without affecting the fundamental power flow. Mathematical model of BUCK-type PWM rectifier is analyzed, advantages and disadvantages of the passive damping and active damping control are compared, and active damping compensator is introduced in the improved SVPWM rectifier. The performance of the proposed method is verified by simulation and experimental results. The distortion of the line current is effectively reduced and the stability of the system is improved. It has a certain engineering value.