Modular multilevel converter(M2C) works as the core of the working condition of high-voltage and highpower electric energy conversion,transmission and other topology,developing its continuous safe and stable operation ability is the primary goal of the M2C converter system.To realize online detection of M2C converter fault state,fast locate the fault sub-module,at the same time to improve M2C fault-tolerant operation ability,a fault diagnosis and fault tolerant operation based on adaptive observer M2C strategy is proposed.The mathematical model of the system is built,and state changes of faulty sub-modules system are analyzed.With internal circulation system and the output current as the observation object,suitable adaptive observer for M2C converter is designed to judge whether monitoring system is in fault state or not,and quickly judge fault point location.Refactoring system voltage modulation signals of the upper and lower bridge ann in each phase is to realize fault tolerant operation under fault condition and to improve safe reliable and continuous operation ability.Last,experimental results verify the feasibility and effectiveness of the proposed control method.%模块化多电平换流器(M2C)作为中高压大功率电能转换、传输等工况的核心拓扑,最大限度的提升其连续安全稳定运行能力是变流器系统设计的首要目标.为实现在线检测M2C故障状态,快速定位故障子模块位置,同时在该过程提升系统的容错运行能力,提出一种基于自适应观测器的M2C故障诊断与容错运行策略.建立系统数学模型,分析M2C子模块故障后系统状态变化;以系统内部环流与输出电流作为观测对象,设计适合M2C的自适应观测器,在线监测系统是否处于故障状态,并迅速判断故障点位置;重构系统各相上、下桥臂电压调制信号,实现故障状态下的容错运行,最大限度提升系统连续安全可靠运行能力;最后通过实验验证了所提控制方法的可行性和有效性.
展开▼
