半波整形模块化多电平换流器动态建模及多目标控制策略  

Dynamic Model and Multi-Objective Control Strategy of Half-Wave Shaping Based Modular Multilevel Converter

作　　者：孙玉巍 陶聪 付超 张泽霖 王琛 王毅 Sun Yuwei;Tao Cong;Fu Chao;Zhang Zelin;Wang Chen;Wang Yi(Hebei Key Laboratory of Distributed Energy Storage and Microgrid North China Electric Power University,Baoding 071003 China)

机构地区：[1]河北省分布式储能与微网重点实验室(华北电力大学),保定071003

出　　处：《电工技术学报》2025年第6期1864-1877,共14页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(52077079);中央高校基本科研业务费专项资金(2022MS072)资助项目。

摘　　要：半波整形模块化多电平换流器(HWS-MMC)是一种新型融合两电平拓扑和模块化多电平拓扑优点的轻型化混合多电平换流器,其利用低频换向开关配合,将多电平单元调制生成的正弦半波翻转为完整正弦波形输出,实现交直流功率变换。该文在分析HWS-MMC基本原理和多电平单元能量平衡机理的基础上,建立反映模块电容电压和直流母线电容电压动态的数学模型,并基于多尺度开关周期平均化方法获得HWS-MMC不含高频和基频开关特性的全平均值动态模型,进而提出考虑并网电流控制、两级直流电压控制以及多电平单元电容相间和相内电压均衡控制的多目标控制策略。最后通过RT-Lab控制硬件在环实时仿真验证了动态模型和控制策略的有效性。The traditional modular multilevel converter(MMC)has drawbacks such as many submodules,large volume and weight,and high cost.The lightweight MMC topologies have become a research hotspot.Half-Wave Shaping MMC(HWS-MMC)is a new lightweight hybrid multilevel converter that integrates the merits of the two-level topology and the MMC topology.The HWS-MMC can reduce the module numbers and voltage stress since the multilevel arm only needs to modulate part of the sinusoidal waveform.In existing studies,phase-shift modulation and third-order harmonic injection methods for energy balance issues of the wide-range operation of HWS-MMC are based on the inverter operation with supply ideal DC voltages supply,and no detailed multi-objective control design has been conducted.Therefore,this paper studies the dynamic model and multi-objective control strategy of HWS-MMC.Firstly,the topology and working principle of HWS-MMC are introduced,and the energy balance mechanism and phase-shift wide-range modulation method are clarified by deriving the arm energy accumulation expression.The mathematical models of internal and external variables are established for HWS-MMC,including grid current dynamics,submodule capacitor voltages,and DC bus capacitor voltage.Then,a fully averaged dynamic model without switching characteristics is obtained and linearized using the multi-scale switching period averaging technique. An overall control strategy is systematically established with the objectives of grid current control, two-stage DC voltage control, and energy balancing control between phases and within an arm. The design method of the multi-loop controllers and commutation control logic are also given. An HWS-MMC system is built on the RT-Lab platform. Experiments are conducted under the grid voltage disturbance, load disturbance, and reactive power regulations. The waveforms, including the AC voltage and current, the DC bus and submodule capacitor voltages, the modulation coefficient and phase-shift angle, and the active and reactive power,

关 键 词：半波整形模块化多电平换流器 动态模型 能量平衡 电压均衡 多目标控制 

分 类 号：TM46[电气工程—电器]