开关电源动态响应怪现象(有图)

本人测试一个开关电源系统,CH1为Vout,CH4为Iout(电子负载CC模式),手动切换满载到空载,空载到满载两种情况.发现Vout的变化规律是反的.
理论上说,满载到空载,Vout是向上突变然后经过setting time稳定.空载到满载,Vout是向下突变然后经过setting time稳定.
而这个系统的波形正好反了.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/55/892151185350426.png?x-oss-process=image/watermark,g_center,image_YXJ0aWNsZS9wdWJsaWMvd2F0ZXJtYXJrLnBuZz94LW9zcy1wcm9jZXNzPWltYWdlL3Jlc2l6ZSxQXzQwCg,t_20');}" onmousewheel="return imgzoom(this);">