边界控制方法在DVR样机研制中的应用  

Boundary Control of Dynamic Voltage Restorers

作　　者：王智勇[1] 吴正国[1] 周卫平[1] 

机构地区：[1]海军工程大学电气与信息工程学院,武汉430033

出　　处：《舰船电子工程》2009年第4期184-188,共5页Ship Electronic Engineering

摘　　要：动态电压恢复器(DVR)可在供电电压发生电压下陷时维持负载电压稳定,以保护敏感负载。由于在正常电力系统中,电压下陷故障出现的频率相对不高,使得DVR的利用率较低。将一种基于二阶开关平面理论的边界控制器应用于DVR系统,使其既可用于电压下陷补偿又能用于稳态下电压电能质量控制,大大提高了设备利用率。通过预测DVR逆变器的某次开关动作后,其系统状态矢量的运动轨迹可得到上述二阶开关平面。将该平面作为状态轨迹沿理想开关平面运动的上界,可约束轨迹使其趋向理想工作点。为考察其动态特性,应用上述控制器的DVR样机针对源端谐波畸变和伴有畸变的下陷电压波形进行了补偿试验。结果证实上述边界控制方案可获得优于其它一些控制策略的谐波补偿效果。Dynamic voltage restorer （DVR） is used to provide load voltage support and protect sensitive toad during voltage sags situation. However, voltage sags do not appear frequently and hence the utilization of the DVR is low. In order to increase the utilization of the DVR, the DVR should operate to compensate any load voltage instability especially the load voltage harmonics and source voltage variations in steady-state operation. A boundary controller using a second-order switching surface is proposed for DVR application for both voltage sags and power quality control under steady-state condition. The switching surface is derived to estimate the state trajectory movement of the DVR after a hypothesized switching action. It results in a high state trajectory velocity along the switching surface. This phenomenon accelerates the trajectory moving towards the target operating point. The dynamic performance of the DVR is verified experimentally with distorted supply voltages and distorted voltage sag situation. Experimental results confirm that the proposed boundary control scheme can achieve better harmonic compensation performance than some other control methods.

关 键 词：电压下陷 动态电压恢复器(DVR) 边界控制 二阶开关平面 谐波补偿 

分 类 号：TM34[电气工程—电机]