Date of Award


Degree Name

Master of Science in Engineering


Electrical and Computer Engineering

First Advisor

Dr. Ikhlas Abdel-Qader

Second Advisor

Dr. Johnson Asumadu

Third Advisor

Dr. Azim Houshyar


Digital Distance Relay, FACTS controllers, protection system, Static S¡mchronous Series Compensator (SSSC), Static Synchronous Compensator (STATCOM)

Access Setting

Masters Thesis-Open Access


Flexible Alternating Current Transmission Systems (FACTS) are increasingly being used to enhance the efficiency and reliability of power system networks. FACTS devices can influence the performance of existing protective system components (specifically distance relays) due to the fact that FACTS change power system quantities such as line impedances, voltages, and currents. Distance relay may mal-operate when FACTS devices are connected since they cause some of the tripping characteristics to change. This thesis investigates the impact on distance relay performance due to compensations using two types of FACTS controllers: Static Synchronous Compensator (STATCOM) and Static Synchronous Series Compensator (SSSC). Analytical study on the effects of STATCOM and SSSC on distance relay performance is conducted. A detailed modeling and simulation of digital distance relay with three zones mho characteristics are also presented along with a verification of the proposed models under a variety of fault types and fault locations. Results from the analytical comparative study are confirmed by the simulation results and both corroborate the fact that we need to address distance relay performance under the different modes of operation of STATCOM and SSSC and that a redesign is essential to better face problems such as in over/under reaching.