Equivalent simulation method based on clamping double sub-module MMC (modular multilevel converter) and considering various locking modes

Abstract

The invention discloses an equivalent simulation method based on a clamping double sub-module MMC (modular multilevel converter) and considering various locking modes. The method comprises: obtaining a bridge arm current of a corresponding bridge arm and a switch signal of an IGBT of each clamping double sub-module of the bridge arm; according to operational parameters, constructing an equivalent circuit of the bridge; and according to the equivalent circuit of the bridge arm, establishing a corresponding simulation system and performing simulation. According to the equivalent simulation method for the MMC, the sub-modules are equivalent to Thevenin equivalent branches by utilizing internal mechanisms of numerical calculation and electromagnetic simulation, so that frequent switch-on or switch-off of a large amount of power electronic devices is avoided and the simulation calculation time is greatly shortened; and at the same time, real diode devices are introduced, so that the locking states of the clamping double sub-modules can be accurately simulated on the premise of ensuring the simulation speed.

Description

technical field [0001] The invention belongs to the technical field of power system simulation, and in particular relates to an equivalent simulation method based on clamping twin sub-modules MMC considering multiple blocking modes. Background technique [0002] In 2001, German scholar R. Marquardt first proposed the modular multilevel converter (MMC) topology. The bridge arms of this topology adopt the form of cascading basic operating units to avoid direct series connection of a large number of switching devices. There is no Issues such as consistent triggering have received extensive attention from academia and industry in recent years, and have been rapidly applied to engineering practice. [0003] like figure 1 As shown, the bridge arm of the MMC topology is composed of multiple sub-modules connected in series. The structure of the sub-modules can be divided into different types according to the needs of the application. At present, half-bridge sub-modules, full-bridge...

AI Technical Summary

Problems solved by technology

This algorithm greatly reduces the dimension of the MMC admittance matrix and speeds up the simulation, but it cannot accurately process the interpolation of the diode, resulting in a large deviation between the system simulation characteristics and the real characteristics when the sub-module is blocked.

In addition, the existing research generally only focuses on the half-bridge sub-module, and there are few studies on the clamped twin sub-module

Images