并联脉宽调制整流器非线性L_2增益环流抑制控制

Circulating-current nonlinear L_2-gain attenuation control of parallel pulse width modulation rectifiers

针对由于模型参数分散和外部干扰引起的并联脉宽调制(pulse width modulation,PWM)整流器环流问题,提出了最优L_2增益电流内环控制与非线性L_2增益零序环流外环控制相结合的控制方法.最优L_2增益电流内环控制不仅可以实现干扰对输出的增益最小,还可以灵活实现并联PWM整流器之间的功率平移.非线性L_2增益零序环流外环控制可以有效抑制由于模型参数不确定和外部干扰引起的环流问题.并联PWM整流器双环L_2增益控制仿真结果表明:相对于传统的比例积分控制方法,该方法可以明显降低并联PWM整流器之间的环流,并可提高并联PWM整流器的供电品质,对于增强系统的稳定性具有重要意义.

For the circulating-current restrain in parallel pulse width modulation(PWM)rectifiers caused by the uncertain model parameters and external disturbances,the new control method,composed by the optimal L2-gain current inner loop control and the zero sequence current outer loop control,is proposed.The optimal L2-gain current inner loop control not only can realize the minimum gain of the disturbance to the output,but also can achieve the power transfer between the parallel PWM rectifiers.The zero sequence current outer loop control can retrain the circulating-current caused by the uncertain parameters and the disturbances.The simulation results of the parallel PWM rectifiers shows that comparing with the traditional proportional-integral control method,the new two loop L2-gain control method can significantly reduce circulating-current between the parallel PWM rectifiers and improve the power supply quality,which is important to improve the stability of the power system.