A voltage measurement based control of a SSSC

Flexible AC Transmission Systems (FACTS) offer the possibility of controlling line transmission parameters in order to optimize and enhance the system characteristics. Static Synchronous Series Compensator (SSSC) is a FACTS that can be used to modify the power flow through a transmission line. Classical SSSC control approach is based on injecting voltage in quadrature with the line current, so that only reactive power is exchanged with the transmission line in order to modify the active power flow. In this paper, a new control approach based on the grid voltage instead of the line current is proposed. Both strategies are compared theoretically. PSCAD/EMTDC simulations have been performed to validate this theory. The results demonstrate that the new control strategy exhibits better results under non-sinusoidal conditions.