【摘要】 为了减少PWM整流器开关频率附近高次谐波的含量,文中采用了三次LCL型滤波器。为了提高系统的稳定性,抑制滤波器的谐振,在双闭环控制的基础上提出了一种基于虚拟电阻思想的控制策略。通过对滤波电容电流的积分处理,改变了系统传递函数的极点,确保了系统的稳定运行。此外,文中对LCL滤波的三相PWM整流器数学模型进行了详细的分析,并从理论和仿真两方面证明了LCL滤波器的优越性能。最后的仿真结果证明了该控制策略是可行的。更多还原

【Abstract】 To reduce the current harmonics around switching frequency of the three-phase pulse width modulation (PWM) rectifiers,an LCL filter has been adopted.To suppress reso- nance of LCL filter and improve stability of system,it is pre- sent that a voltage and current double loops control strategy based on virtual resistor concept.Unstable pole of transfer function of system is changed though filter capacitor current is integral.Moreover mathematical model of three-phase PWM rectifier with LCL filter has been analyzed in detail.LCL filter is more effective to attenuate switching harmonics and to reduce harmonic distortion at lower switching frequency are also proved by theory and result of simulation.更多还原