基于高频隔离AC/AC变换器的动态电压恢复器

Dynamic Voltage Restorer Based on High-frequency Isolated AC/AC Converter

针对电网电压跌落、突升所带来的电能质量问题,提出了一种基于高频隔离AC/AC变换器的动态电压恢复器(DVR)。该恢复器拓扑结构由高频隔离AC/DC变换器和全桥Dual-Buck构成,具有体积小、与电网隔离和无开关管直通问题等特点。详细描述了恢复器的拓扑构成、工作原理、脉宽调制(PWM)策略和双闭环控制策略。搭建了DVR的仿真系统和实验样机,模拟了电压跌落、电压突升等工况。仿真及实验结果表明,所提DVR能够快速且有效地补偿电网电压波动。

Aiming at the power quality problems caused by grid voltage drop and sudden rise,dynamic voltage restorer(DVR)based on high-frequency isolated AC/AC converter is proposed.The restorer topology consists of a high-frequency isolated AC/DC converter and a full-bridge Dual-Buck,which has the characteristics of small size,isolation from the power grid and no switch-through problem.The topology,working principle,pulse width modulation(PWM)strategy and double closed-loop control strategy of the restorer are described in detail.The simulation system and experimental prototype of the DVR are built,which simulates voltage sag and swell conditions.Simulation and experimental results show that the DVR can effectively compensate for grid voltage fluctuations.