摘要
为解决传统牵引供电系统中存在的电能质量和过分相问题,介绍了一种基于模块化多电平换流器的多端柔性直流输电系统(MMC-MTDC)的新型牵引供电系统。分析了新型牵引供电系统中出现的直流电压、电流二倍频波动问题,主要有两方面原因:一是受端单相H桥型模块化多电平换流器(SPH-MMC)正常工作时内部环流将流入直流侧引起直流电压、电流二倍频波动;二是送端三相MMC因电网电压不平衡时桥臂中存在的零序电压分量造成直流电压、电流二倍频波动。为此,对于SPHMMC基于准比例谐振控制器和二阶广义积分器设计环流抑制控制器;对于三相MMC设计无需锁相环和无需电流正、负序分解的电网不对称故障控制器,利用电压补偿技术设计直流侧二倍频波动抑制器。最后,以三端单相-三相MMC-MTDC仿真模型为例验证该文的分析结果和所提出的控制策略。
To solve the problems of power quality and split section that exist in the traditional traction power supply system（ TPSS）,a novel TPSS that based on the modular multilevel converter multi terminal high voltage direct current（ MMC-MTDC） was introduced. The issue of double frequency ripples in the DC voltage/current which appears in the novel TPSS was analyzedand it was caused by two reasons; One reason is the circulating current of single-phase H bridge MMC（ SPH-MMC） flow into the DC network. Another is a zero sequence voltage component existing in the bridge voltage of three-phase MMC in unbalanced grid condition. To suppress the double frequency fluctuation,a circulating current suppressing controller based on the quasi proportional resonant（ quasi-PR） regulator and the second order generalized integrator（ SOGI） filter was design for SPHMMC; And a controller without PLL and separate positive and negative sequence components of current was proposed for three-phase MMC,besides a DC voltage ripple suppressing control strategy based on the voltage compensation was proposed. Finally,a three terminal single-phase to three-phase MMC-MTDC simulation model was built to support the theoretical analysis and proposed control schemes.
作者
宋平岗
吴继珍
董辉
Song Pinggang Wu Jizhen Dong Hui(School of Electrical and Automation Engineering East China Jiaotong University Nanchang 330013 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2017年第9期80-91,共12页
Transactions of China Electrotechnical Society
基金
国家自然科学基金项目资助(51367008)
关键词
多端直流输电
牵引供电系统
模块化多电平换流器
二倍频波动
Multi-terminal direct current（MTDC）
traction power supply system
modular multilevel converter（MMC）
double frequency fluctuations
