在线等!!逆变电源电路输出波形不对,有图,请教,谢谢!

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按上图在输入端加入12V,在变压器的次级输出波形如下:

开关频率为55k:
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开关频率为143k
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开关频率不同,波形变化很大,都不正常.如下修改电路图,谢谢!