STATCOM modeling impacts on performance evaluation of distance protection of transmission lines

摘要

In this paper, the impact of STATCOM on the apparent impedance seen by conventional distance relaynprotecting a transmission line is investigated. Analytical results are presented, and verified by detailednsimulations. It is shown that the implications of applying STATCOM on distance relay are highly dependentnon the sophisticated modeling of STATCOM especially its control system considering practical constraints.nAccurate modeling of the distance relay, particularly the analog input signals are also important in extractingnreliable results. Practical constraints of the STATCOM are modeled in full details. It is demonstrated thatnwhen the STATCOM’s limits are modeled in detail, i.e., the STATCOM is not considered an ideal reactivepowernsource the STATCOM’s impact on the performance of distance protection is less severe than in thencase where limits are ignored and thus ideal controllers are applied. This is a remarkable point for the utilitiesnas not to overestimate the severity of the impact of STATCOM on conventional distance protection ofntransmission lines. Six different phase-to-phase and phase-to-ground measuring units of the distance relaynare simulated to resemble the behavior of the relay. Different power system operating conditions, STATCOMncontrol system settings and fault scenarios are investigated. The STATCOM effects on distance relay trippingncharacteristics are also analyzed. Copyright # 2010 John Wiley & Sons, Ltd.