单周期控制开关电容DC-DC变换器

One-Cycle Controlled Switched Capacitor Based DC-DC Converter

传统的开关电容DC-DC变换器通常采用PWM控制方法,以输出电压或者开关管的电流作为反馈信号来调节占空比,然而占空比信号的变化不能即时跟随输入电压或负载的变化,因而PWM控制方法的动态调节响应较慢。单周期控制方法是一种非线性控制技术,该技术利用开关变换器的非线性特点,对开关变量平均值实现即时的动态控制,只需在一个开关周期之内就能使开关变量平均值达到稳态,因而具有较快的响应速度。本文介绍了单周期控制方法的基本原理,并将该方法应用于一个恒定频率的升压(5V/12V)开关电容DC-DC变换器的控制。仿真结果表明该方法是可行的。

Conventional switched capacitor based converters usually use PWM control method, the feedback signal is the input voltage or the current of the switches. But the duty-cycle signal cannot vary with the input voltage or the load iostantaneously, so this method cannot obtain fast dynamic response. One-cycle control method is a kind of nonlinear control technique, this technique takes advantages of the nonlinear nature of switching converters, and achieves instantaneous dynamic control of the average value of the switched variable, more specially it takes only one switching cycle for the average value of the switched variable to reach a new steady state after a transience, so this technique can provide fast dynamic response. The operational principle of one-cycle control method is introduced in this paper, and this control method is applied to control a step-up (5 V/12 V) SC based DC-DC converter with a constant frequency, the simulation results manifested the feasibility of this control method.