考虑死区特性的全桥型MMC状态空间平均化建模方法  

State Space Averaging Modeling Method of Full-bridge Modular Multilevel Converter Considering Dead-time Characteristics

作　　者：潘可盈 井航 冯谟可 许建中 PAN Keying;JING Hang;FENG Moke;XU Jianzhong(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University),Beijing 102206,China;State Key Laboratory of Power Transmission Equipment Technology(Chongqing University),Chongqing 400044,China)

机构地区：[1]新能源电力系统全国重点实验室(华北电力大学),北京市102206 [2]输变电装备技术全国重点实验室(重庆大学),重庆市400044

出　　处：《电力系统自动化》2024年第15期141-150,共10页Automation of Electric Power Systems

基　　金：国家电网公司科技项目(5500-202255495A-3-0-ZZ)。

摘　　要：为避免同侧互补导通的功率管发生直通短路故障,模块化多电平换流器(MMC)中开关器件需要设置死区时间,死区的存在会产生死区效应且死区难以被彻底消除。随着电力电子器件开关频率的不断提高,死区占比增加,死区影响已不容忽视。针对死区效应越来越显著和MMC仿真耗时过长的问题,提出一种考虑死区特性的提速模型。首先,对级联子模块含死区时间的实际开关状态进行端口工况特征扫描,通过含死区的端口特性识别出各子模块实际工作模态,建立状态空间方程。其次,基于状态空间平均法,以占空比为纽带统一子模块不同的模态性质,建立子模块分立元件模型。进一步,根据平均值模型的解耦特性,建立桥臂集中模型,提高仿真建模效率。最后,在PSCAD/EMTDC仿真软件平台上分别搭建全桥型MMC的详细模型、子模块分立元件模型与桥臂集中模型。仿真结果表明,所提模型具有较高的精度和运行效率,可以更好地满足实际工程仿真需求。To avoid the flow-through short-circuit fault of the power transistor with complementary conduction on the same side,the switching devices in the modular multilevel converter(MMC)need to set the dead time.The existence of the dead time will generate dead-time effect and it is difficult to eliminate the dead time.With the continuous improvement of the switching frequency of power electronic devices,the proportion of dead time increases and the influence of dead time cannot be ignored.Aiming at the problem that the dead-time effect is becoming more and more significant and the MMC simulation takes too long,this paper proposes a speed-up model considering the dead-time characteristics.Firstly,the port condition characteristics of the actual switching state of the cascaded sub-modules with dead time are scanned,and the actual working modes of each sub-module are identified by the port characteristics with dead time.The state space equation is then established.Secondly,based on the state space average method,the duty cycle is used as a link to unify the different modal properties of the sub-modules,and the submodule discrete component model is established.Further,according to the decoupling characteristics of the mean value model,a bridge arm centralized model is established to improve the efficiency of simulation modeling.Finally,the detailed model,the submodule discrete component model,and the bridge arm centralized model for the full-bridge MMC are built on the PSCAD/EMTDC simulation software platform.The simulation results show that the proposed models have high accuracy and operation efficiency,which can better meet the demands of practical engineering simulation.

关 键 词：模块化多电平换流器 死区 状态空间平均法 平均值模型 高效电磁暂态建模 

分 类 号：TM46[电气工程—电器]