Effect of STATCOM – ES on Distance Relay Operation in a Series Compensated System

Flexible AC transmission systems or FACTS help in a big way to realize a smart grid, which can be used by utilities to reconfigure power flows in real time, maximizing throughput and minimizing losses. It will also facilitate incorporating wind, solar, and other intrinsically intermittent sources of energy into the grid. A static synchronous compensator equipped with energy storage (STATCOM - ES) can provide two degrees of freedom to inject both real and reactive current into the bus. This paper aims at developing the DQ model of a series compensated system which also incorporates a static synchronous compensator with energy storage and analyzing its effect on the operation of distance relay. The emulated conductance and susceptance by STATCOM - ES under various operating conditions is determined and its’ effect on impedance at the generator terminals is investigated. Effect of real and reactive power exchange by STATCOM – ES on the measured impedance and operation of distance relay is analyzed.