※ 引述《noko (爆肝吧...男孩)》之铭言： : 想请教一下,在一般的dcdc里面 : 大部分都会用PWM Control : 而PWM普遍看到的都是Voltage mode跟Current mode control : 小弟不才有个问题想了很久 : 在电流模式里面,DCDC外部可以看作单极点系统 : 电压模式DCDC外部是双极点系统 : 而在电流模式里面,因为电感可以等效为一个电阻效应 : 那为何可以等效成电阻效应呢? : 请板上的大大能帮忙解惑,谢谢 http://www.powermanagementdesignline.com/howto/202802181 节录一段出来.... Current-mode control is desirable because the CMC loop in effect forces the peak current to be the same for each switch cycle as long as Vc is constant. Thus, the inductor in combination with the CMC loop can be thought of as a current source. Unlike voltage-mode control, the inductor L and output filter capacitor, Co, do not contribute a complex pole pair to the overall system loop. The removal of a power pole due to L in the CMC system loop removes the need for a corresponding zero in the overall system compensation network. A single RC network is adequate for optimal CMC system compensation, a significant reduction in complexity for tuning system performance. 如果这样还是觉得不明所以 最基本的方式 可以去推导电流模式的电流控制回路的转移函数 跟电压模式的转移函数做比较 两者的control-to-output transfer function 前者少一个pole --

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