多类型子模块MMC电磁暂态通用建模和实现方法

Generalized Electromagnetic Transient Equivalent Modeling and Implementation of MMC With Arbitrary Multi-type Submodule Structures

模块化多电平换流器(modular multilevel converter,MMC)电磁暂态高效建模的难点,在于对桥臂中大量结构相同的级联子模块(sub-module,SM)进行等效的同时保证消去的节点信息都可以被精确反解。提出一种针对多类型MMC的电磁暂态通用建模和实现方法,它对传统的单端口MMC和新近出现的双端口MMC都适用。同时提出一种MMC拓扑自动识别方法,可以大幅降低模型用户在对特定拓扑建模时候的工作量,同时绝大部分模型代码都可以继承。最后,在PSCAD/EMTDC中分别以单端口和双端口MMC为例,对所介绍的等效建模算法进行了验证,结果表明所提出的算法具有很强的通用性。

The key issue of electromagnetic transient (EMT) modelling of modular multilevel converters (MMC) is calculation of equivalent circuit of entire MMC arm containing a large number of cascaded sub-modules (SM) with identical structure. During this process, all internal information should be preserved. This paper proposes a general EMT modelling approach for arbitrary multi-port MMC topologies, also suitable for traditional single-port MMC and emerging two-port MMC. A submodule topology identification method is proposed to minimize the efforts of the model users when they have specific MMC topologies at hand. In addition, the model codes can be inherited to a large extent. Finally, the approaches are validated in PSCAD/EMTDC with results of very good applicability of the general algorithm and unified implementation method .