基于双极性直接式AC/AC变换的单相动态电压恢复器

动态电压恢复器(DVR)是串接于电源与负荷之间用以实现快速补偿系统电压波动的电力电子装置。针对传统基于电压源型逆变器的DVR存在的储能设备所带来的问题以及基于脉宽调制(PWM)型直接式AC/AC变换的DVR所存在的换流、飞跨电容电压平衡等问题,文中提出了一种基于双极性直接式AC/AC变换的单相DVR。该DVR所使用的PWM型AC/AC变换拓扑具有输入、输出共地特点,同时,该DVR能够在较为简单的控制策略下实现系统电压的双极性调控且其在运行过程中有效解决了换流问题。为了验证所提出的DVR的工程价值,在理论分析的基础上,搭建了1 kW的实验平台对其合理性与有效性进行了验证。

Single-phase Dynamic Voltage Restorer Based on Bipolar Direct AC/AC Conversion

Dynamic voltage restorer (DVR) is a power electronic device connected in series with source and load, which is used to rapidly compensate voltage fluctuation in the power system. However, due to the energy storage equipment, the conventional DVR based on voltage source inverters (VSIs) has some shortcomings. And the DVR based on direct AC/AC conversion with pulse width modulation (PWM) has the shortages of commutation problem and voltage balance of flying capacitor. Therefore, this paper proposes a single-phase DVR based on bipolar direct AC/AC conversion. The AC/AC converter topology with PWM used in the proposed DVR has the characteristics of common grounding between the input and output ports. In addition, the proposed DVR can achieve bipolar voltage regulation with a simple control strategy and effectively solve the commutation problem during operation. In order to verify the engineering value of the proposed DVR, a 1 kW experimental platform has been built to verify its rationality and effectiveness on the basis of theoretical analysis.