基于PWM开关变压器的动态电压恢复器研究

Research on Dynamic Voltage Restorer Utilizing a PWM-switched Autotransformer

提出了一种基于PWM开关变压器的单相在线式动态电压恢复器(DVR),PWM开关变压器由交流斩波器及串联变压器组成,该DVR可补偿电压凸起和凹陷,无需直流储能环节和锁相环,且具有相位自动跟踪能力。采用新的控制策略及电压检测方法,使系统能够快速识别电压凸起和凹陷并做出相应补偿。系统可工作在降压状态,可应用于节能场合,并设有旁路开关,提高了供电可靠性。设计了10 kW实验样机,实验结果表明此处所提出的DVR具有较好的动态响应、补偿及运行性能。

This paper proposes, a single-phase on-line dynamic voltage restorer （DVR） based on a PWM-switched au- totransformer composed of AC-chopper and series transformer that can compensate voltage sag or swell avoiding DC storage energy devices, and the DVR has the ability of phase automatic tracking without phase-locked loop.This pa- per presents new control topology, as well as the voltage detection method, which is able to quickly recognize the volt- age sag or swell condition and correct the voltage by either boosting the input voltage during voltage sag events or re- ducing the voltage during swell events.The DVR also can apply to energy conservation when working on step-down condition, and it has bypass switch improving reliability of power supply.Designed a 10 kW prototype, and experimen- tal results repeal that the proposed scheme has a fast time response, compensation and operation performance.