一种处理AC斩波器短路问题的新方法

提出了一种基于电流极性检测的开关控制策略,解决了基于电压极性检测的开关控制策略在输入电压过零点检测错误时会导致短路的问题.该方法是根据所检测出的电流极性对存在延时的2个PWM信号进行适时选取对应不同开关,不仅减少了功率损耗,降低了电磁干扰,而且可靠性更高、谐波更少、效率更高.用Matlab对2种方法分别进行了仿真并比较...

Solution to short circuit of AC chopper

A switching strategy based on current direction detection is proposed to avoid the short-through problem of conventional voltage direction detection strategy in case of faulty zero-crossing detection,which selects different switches in-time for two delayed PWM signals according to detected current direction,resulting in reduced power loss,improved EMI characteristics,higher reliability,less harmonics and better efficiency.Both strategies are simulated and compared with Matlab to verify the superiority of the proposed strategy.The prototype experiment of MCU DSPIC33FJ64MC506 combined with IGBT module is carried out and the experimental results are in accordance with simulative results.