三相电压型PWM整流器改进双闭环控制方法

An Improved Double Closed Loops Control of the Three-phase Voltage-sourced PWM Rectifier

三相电压型脉宽调制(PWM)整流器由于具有高功率因数和能量可双向传输等优点而被广泛应用。为提高PWM整流器控制性能,通常采用电压外环、电流内环的双闭环控制策略。然而,传统控制方式中,由于电压外环的非线性特征未完全体现和电流内环的解耦不彻底,致使直流电压不够稳定及交流电流波形品质因数不高。针对上述问题,分别对电压型PWM整流器的外环和内环加以改进,提出了一种新颖的双闭环控制策略。通过理论说明、仿真分析和实验验证,证明了所提控制策略的正确性和有效性。改进的双闭环控制方法能更好地稳定PWM整流器的直流电压,提高其功率因数,更利于实际应用。

The three-phase voltage-sourced pulse width modulation（PWM） rectifier is widely used because of its high po- wer factor and hi-directional power flow characteristics.To improve the control performance of PWM rectifier,the volt- age outter loop and current inner loop control strategy are commonly used.However,the traditional control method has some shortcomings.Under the traditional control method, the nonlinear characteristics of DC voltage is not fully reflect- ed, and the decoupling of the current inner loop is not completely decoupled which results in DC voltage is not stable enough and the AC current waveform quality is not high.In order to improve the static and dynamic performances of the rectifier, an novel double closed loop control strategy is proposed which enhances the DC voltage stability and AC current waveform quality.The correctness and effectiveness of the proposed control strategy are proved by theoretical proof,simulation analysis and experimental verification.