直流电机驱动电路-MOS管发烫厉害,怎样解决(附原理图,波形图)?有回必答

原理图如下:电机带正常负载时,IRFP460发热比较厉害.
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MOS管栅极(驱动波形)图如下:方波基本正常,但方波中谐波比较厉害.
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直流电机两端的波形基本是比较正常,谐波量很少.