Frequency-domain analysis of the static synchronous series compensator

This paper presents an analytical formulation of the frequency-domain characteristics of the static synchronous series compensator (SSSC). This paper investigates the characteristics of using two different types of SSSC controllers-one with quadrature voltage regulation (V_q-controlled SSSC) and another with impedance regulation (X_q-controlled SSSC). The influence of the controller parameters on the characteristics is investigated and it is demonstrated that an SSSC-compensated transmission line displays an impedance minimum at a subsynchronous frequency similar to a capacitively compensated transmission line. The analytical results are validated with the results obtained by time-domain simulations.