【摘要】 为抑制由PWM逆变器输出的共模电压而导致电机轴承的损坏,提出了前馈有源滤波器。滤波器包括无源共模电压检测网络,推挽电路以及四绕组共模变压器。滤波器输出与共模电压幅值相同极性相反的补偿电压,将其叠加到逆变器输出上,从而达到消除共模电压进而消除轴电压和轴承电流的目的。文中还给出了部分滤波器参数的确定方法。仿真和实验结果验证了该滤波器可以显著地抑制电机端共模电压,从而减小了变频器输出的负面影响如轴电压,轴承电流等, 延长了轴承的寿命,提高了PWM驱动系统的可靠性。更多还原

【Abstract】 Feed-Forward-Type active filter is proposed in this paper, which consists of a passive common-mode voltage detection network, a push-pull circuit, and a four-winding transformer to eliminate the negative effects of shaft voltage and bearing current in a PWM inverter drives. This filter can impose a compensating voltage with the same amplitude but with the opposite polarity to the common-mode voltage generated by the PWM inverter. Some design considerations of the filter are also given in detail. Simulation analysis and experimental results confirm the validity of the proposed filter that the common-mode voltage at motor terminal is eliminated almost completely and shaft voltage and bearing current are unobvious. It can contribute to enhance bearing life and improve reliability of PWM drive systems.更多还原