基于换相面积理论的混合多馈入直流输电系统连续换相失败抑制策略  

Continuous Commutation Failure Suppression Strategy for Hybrid Multi-infeed HVDC Systems Based on Commutation Area Theory

作　　者：张香松 王长江[1] ZHANG Xiangsong;WANG Changjiang(School of Electrical Engineering,Northeast Electric Power University,Jilin 132012)

机构地区：[1]东北电力大学电气工程学院,吉林132012

出　　处：《电气工程学报》2025年第1期259-270,共12页Journal of Electrical Engineering

基　　金：国家电网公司科技资助项目(5100-202099271A-0-0-00)。

摘　　要：为解决混合多馈入直流输电系统中传统直流连续换相失败导致的电压跌落和功率中断问题,提出一种适用于混合多馈入系统的连续换相失败抑制策略。首先,基于换相面积理论分析了传统直流的换相失败机理;然后,采用变斜率函数设计了一种动态非线性低压限流控制器(Voltage dependent current order limiter,VDCOL),灵活调控VDCOL曲线斜率来限制直流电流的增长速率,减小换相需求面积;同时,根据直流电流与模块化多电平换流器(Modular multilevel converter,MMC)无功输出量之间映射关系,设计了一种考虑无功容量约束的MMC快速无功控制器,实时调整MMC逆变器发出的无功来提升换相电压,增大换相供给面积,进而构建出一种基于换相面积理论的混合多馈入系统连续换相失败抑制策略;最后,在PSCAD/EMTDC中搭建了仿真系统模型进行对比分析,结果表明所提控制策略可有效提升传统直流抵御连续换相失败的能力。In order to solve the voltage drop and power interruption caused by the continuous commutation failure of line commutated converters based high voltage direct current(LCC-HVDC)in hybrid multi-infeed DC transmission(HMIDC),a continuous commutation failure suppression strategy suitable for HMIDC is proposed.Firstly,the commutation failure mechanism of LCC-HVDC is analyzed based on the commutation area theory.Then,a dynamic non-linear VDCOL controller is designed by using variable slope function,which limits the growth rate of DC current and reduces the area of commutation demand by changing the slope of VDCOL curve.Meanwhile,the mapping relationship between DC current and MMC output reactive power is established,and a MMC fast reactive power controller with capacity constraints is designed to increase the commutation voltage and commutation supply area by adjusting the reactive power emitted by the MMC inverter.Furthermore,a continuous commutation failure suppression strategy based on commutation area theory is constructed for HMIDC.Finally,the system model is built in PSCAD/EMTDC for comparative analysis,the results show that the proposed control strategy can effectively improve the ability of LCC-HVDC to resist continuous commutation failure.

关 键 词：混合多馈入直流输电系统 连续换相失败 换相面积 直流电流 换相电压 

分 类 号：TM721[电气工程—电力系统及自动化]