Statcom based on modular multilevel converter: Dynamic performance and transient response during ac network disturbances

This paper presents detailed assessment of the behaviour of STATCOM based on modular multilevel converter during steady-state and transient operation. The steady-state performance of the presented STATCOM is examined when it provides autonomous voltage regulation across number of switch loads. Its transient response is examined by subjecting the test system where STATCOM is connected to symmetrical and asymmetrical ac network faults. In this work, STATCOM power circuit is modelled using detailed switch model of modular converter with 16 cells per arm, including capacitor voltage balancing strategy, and control systems are represented detail (dc and ac voltage regulars, and current controller). Simulations conducted in Matlab-Simulink enlivenment are used to assess the STATCOM performance.