动态电压恢复器的时间优化补偿策略研究  

Analysis of time optimal compensation strategy for dynamic voltage restorer

作　　者：党存禄[1,2] 严鋆[1] 张晓英[1,2] 

机构地区：[1]兰州理工大学电气工程与信息工程学院,甘肃兰州730050 [2]甘肃省工业过程先进控制重点实验室,甘肃兰州730050

出　　处：《电力系统保护与控制》2011年第5期11-16,共6页Power System Protection and Control

基　　金：甘肃省自然科学基金资助项目(0809RJZA004);兰州理工大学优秀青年教师培养资助项目(Q200814)~~

摘　　要：动态电压恢复器(DVR)是缓解电压跌落问题最经济、有效的用户电力装置,它的补偿能力指标是持续补偿时间。以补偿电压跌落时DVR装置的最大持续补偿时间为控制目标,通过调整负荷电压超前跌落电网电压的相位角β,提出一种新的时间优化补偿策略。为减轻DVR运行时对负荷的扰动,使补偿开始和结束的暂态过程更平稳,新策略采取了β按恒定步长Δβ缓慢变化的控制方法,并根据DVR装置的T-β曲线,通过判断特定量符号决定β角的补偿方向。此种β角控制方法避免直接求解β的最优解,计算量小。仿真结果证明,新策略能获得比最小能量补偿策略更长的DVR持续补偿时间,有效利用了DVR的直流母线储能。Dynamic voltage restorer（DVR）has been considered to be a cost-effective custom power device,which alleviates voltage sags.The compensation capability index for DVR is compensation duration.To maximize compensation duration of DVR device when compensated voltage sags,a novel time optimal compensation strategy is proposed,and the novel strategy is implemented by controlling the phase angleβbetween load voltage phasor and supply voltage phasor.In order to reduce disturbances to loads and smoothen transient processes at the beginning and end of compensation,the proposed strategy adopts a control method thatβ changes progressively by constant stepΔβand determines the compensating direction by identifying signs of specific variables,according to T-βcurve.This control method forβavoids directly computing optimalβand has less calculation.The simulation results illustrate that the proposed strategy can obtain longer compensation duration and utilize more DC-link energy for DVR,compared with minimum energy compensation strategy.

关 键 词：电能质量 电压跌落 动态电压恢复器(DVR) 补偿策略 时间优化补偿 

分 类 号：TM761.1[电气工程—电力系统及自动化]