Two-level 24-pulse voltage source converter based static synchronous compensator with constant DC bus voltage

Abstract

In this article, a 2-level 24-pulse voltage source converter based static synchronous compensator consisting of two sets of 2-level 24-pulse voltage source converters gated at the fundamental frequency is proposed for regulating the voltage in a transmission line. The static synchronous compensator is operated at a constant DC-link voltage, which is different from the common operation strategy with variable DC-link voltage. The phase angle difference between the two sets of 2-level 24-pulse voltage source converters is varied for controlling the reactive power, which in turn, regulates the desired voltage at the terminals. The static synchronous compensator is connected to a 132-kV/60-Hz system, and the performance is evaluated by varying the reference reactive power, controlling the terminal voltage under constant loads, and regulating the terminal voltage under switching on the inductive and capacitive loads. The proposed model of the static synchronous compensator is developed using MATLAB/Simulink SimPowerSystems toolboxes (The MathWorks, Natick, Massachusetts, USA), and simulation results are presented for demonstrating its steady-state and dynamic performance.