不平衡电网模块化多电平矩阵换流器的控制策略  

Control Strategy of Modular Multilevel Matrix Converter Under Unbalanced Grid Conditions

作　　者：程启明 谢怡群 马信乔 叶培乐 周雅婷 傅文倩 CHENG Qiming;XIE Yiqun;MA Xinqiao;YE Peile;ZHOU Yating;FU Wenqian(College of Automation Engineering,Shanghai University of Electric Power,Shanghai Key Laboratory Power Station Automation Technology Laboratory,Shanghai 200090,China)

机构地区：[1]上海市电站自动化技术重点实验室(上海电力大学自动化工程学院),上海200090

出　　处：《高电压技术》2023年第5期1975-1984,共10页High Voltage Engineering

基　　金：国家自然科学基金(61905139);上海市电站自动化技术重点实验室资助项目(13DZ2273800)。

摘　　要：为了减少输电线路损耗,在海上风力发电等背景下,低频交流输电系统应运而生,它通过模块化多电平矩阵换流器(modular multilevel matrix converter,M^(3)C)直接实现从低频到工频的AC/AC变换。研究了基于M3C的AC/AC系统在发生不对称故障时的控制策略。首先分析了M^(3)C的电路结构和工作原理,然后针对系统故障不对称的情况,对电压电流进行正负序分离,再基于M^(3)C系统双αβ0变换的数学模型与输入侧、输出侧系统的无源性,推导出输入侧和输出侧的无源控制规律,且通过调节循环电流实现桥臂电容电压控制。最后在仿真实验平台上,在两种不同工况下对所提的不平衡电网下M^(3)C的两侧无源控制策略进行实验,仿真实验结果表明了所提的M3C无源控制策略的正确性和有效性。To reduce transmission line losses,low frequency AC transmission system emerges under the background of offshore wind power generation,and it directly realizes AC/AC conversion from low frequency to power frequency through modular multilevel matrix converter(M^(3)C).The control strategy of an AC/AC system based on M^(3)C is studied in this paper in case of asymmetric faults.The circuit structure and working principle of M 3 C are analyzed primarily.Then,the positive-and negative-sequence separation of the voltage and current is carried out in view of the asymmetry of system fault.Next,on the strength of the mathematical model of M^(3)C system after the doubleαβ0 transformation and the passivity of the input side and the output side system,the passivity-based control laws of input side and output side are deduced,and the bridge arm capacitor voltage is controlled by adjusting the circulating current.Ultimately,on an experimental platform,the proposed PBC control strategy of M 3 C both sides under an unbalanced power grid is tested under two different working conditions.The validity and availability of the proposed strategy are certified by the experimental results.

关 键 词：海上风力发电 模块化多电平矩阵换流器 不平衡电网 无源控制 PI控制 双αβ0变换 

分 类 号：TM46[电气工程—电器]