Operation and Control of STATCOM

The Static Synchronous Compensator(STATCOM) as the shunt Voltage-Source Converter-Based FACTS (VSC-FACTS) device is introduced in this paper. In this paper the basic operation and control strategy of the STATCOM is presented. The control of VSC-FACTS is based on d-q transformation and decoupled control. Therefore the concept of direct and quadrature axes and Park Transformation is presented. The basic component of VSC-FACTS is a converter capable of generating a three phase, almost sinusoidal voltage. Shunt compensation is well-known concept in AC power systems to control the reactive power flow and hence regulate the bus voltage. When the real power demand of the load increases the amount of the required reactive power also increases and shunt compensation is required to provide this additional reactive power demand. The main objective of any AC transmission or distribution line compensation is to increase the steady state and short term power transfer capability of the existing transmission systems. This paper describes the general concept of AC transmission system compensation using tools such as shunt capacitive or reactive compensation and then the new concept of solid - state, converter-based Flexible AC Transmission Systems (FACTS) is introduced. The paper reviews the previous works on FACTS schemes.