Multi-pulse switching functions modeling of flexible AC transmission systems devices

Abstract

This article develops a novel switching function model for the static synchronous compensator, the static synchronous series compensator, and the unified power flow controller flexible AC transmission system devices based in a multi-pulse voltage-sourced converter topology for 6-, 12-, 24-, and 48-pulse configurations. This novel model correctly represents commutations of semiconductor devices in a voltage-sourced converter, which consequently allows a precise representation of harmonic components present in signals of actual flexible AC transmission system devices. The models are carried out in the original abc power system coordinates. As an introduction to the more complex arrangements, the derivation of the simplest six-pulse voltage-sourced converter-based switching function model is explained. The effectiveness and precision of the proposed models are validated against simulations carried out in the professional computer program PSCAD/EMTDC.