Modelling, design and comparison of PI and PID controllers for Static Synchronous Compensator (STATCOM)

Abstract

The Static Synchronous Compensator (STATCOM) is one of the most widely used Flexible AC Transmission System (FACTS) device which is based on a voltage source converter with a dc link capacitor. This paper presents the mathematical modelling of STATCOM in dq domain, with the Q-Vdc controller to control the reactive power flow in the system and to maintain the dc voltage at a constant value. The control of the voltage source converter(VSC) is achieved by controlling the duty cycle of the inverter devices in Park's domain (dd and dq). Design, analysis and comparison of Proportional-Integral (PI) and Proportional-Integral-Derivative (PID) controllers for this scheme is presented.