LLC 30V/5A 请求诊疗(有图)

输入90-264V AC,输出30V/5A,有APFC.
磁芯:EE35;
Np:Ns=40T:6
Lp:480uH,Lk:100uH,Cr:33nF.
原边电流波形
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500) {this.resized=true; this.width=500; this.alt='这是一张缩略图，点击可放大。\n按住CTRL，滚动鼠标滚轮可自由缩放';this.style.cursor='hand'}" onclick="if(!this.resized) {return true;} else {window.open('http://u.dianyuan.com/bbs/u/76/1695931239172183.gif');}" onmousewheel="return imgzoom(this);">
漏极电压波形
500) {this.resized=true; this.width=500; this.alt='这是一张缩略图，点击可放大。\n按住CTRL，滚动鼠标滚轮可自由缩放';this.style.cursor='hand'}" onclick="if(!this.resized) {return true;} else {window.open('http://u.dianyuan.com/bbs/u/76/1695931239172198.gif');}" onmousewheel="return imgzoom(this);">
效率:220VAC--90.5%  110VAC--88.7%
有低频噪声,请高手诊断,谢谢!