摘要
提高MMC-HVDC换流器开关器件的电流利用率可扩大同一换流器的功率输送能力,间接降低MMC-HVDC换流器的造价。鉴于此,本文根据模块化多电平换流器(modular multilevel converter,MMC)的工作特点,提出了一种考虑采用二倍频谐波电流注入的新型环流控制策略,并通过数学推导给出了二倍频正弦谐波注入时谐波幅值和相位的计算方法,采用本方法可减小桥臂峰值电流达20%以上,提高了换流器的电流利用率,从而提升换流器有功功率输送能力达25%。最后在RTLAB中搭建MMC仿真模型,并对新型环流抑制策略进行了仿真验证,仿真结果验证了所提控制策略的理论正确性和实施有效性。
The power transmission ability of a same converter can be expanded by improving the current utilization ratio of switching devices of modular multilevel converter based HVDC(MMC-HVDC),and hence the cost of converter of MMC-HVDC can be reduced.Based on the characteristics of MMC,this paper presents a new type of circulating current control strategy considering double frequency harmonic current injected,and gives mathematical deduction of amplitude and phase of the double frequency sinusoidal harmonic current injected.This new strategy can reduce the peak value of the arm current up to20%,improve the current utilization rate of the converter,and enhance the power delivery capacity of the converter up to25%.At last,the simulation model of MMC is established in RTLAB,and the new circulating current suppression strategy is carried out.The simulation results verify the accuracy and effectiveness of the proposed control strategy.
作者
朱良合
盛超
卢启付
骆潘钿
朱弘琪
黄韬
刘正富
ZHU Lianghe;SHENG Chao;LU Qifu;LUO Pandian;ZHU Hongqi;HUANG Tao;LIU Zhengfu(Electric Power Research Institute, Guangdong Power Grid Co., Ltd., Guangzhou 510080, China)
出处
《南方电网技术》
北大核心
2018年第8期8-16,共9页
Southern Power System Technology
关键词
模块化多电平换流器
桥臂峰值电流
二倍频
环流抑制策略
电流利用率
modular multi-level converter
peak value of the arm current
double frequency
circulating current suppression strategy
current utilization rate
