Operational Experience and Performance Evaluation of Prime System Integrity and Protection Schemes (SIPS) in India

Indian power system is characterized by cluster of Extra High Voltage Alternating Current (EHVAC), High Voltage Direct Current (HVDC), Ultra High Voltage Direct Current(UHVDC), Multi-Terminal HVDC (MTDC-HVDC) transmission network, large distribution network across the country along with conventional generation having Ultra Mega Power Plants (UMPP) and increasing penetration of Renewable Energy Sources (RES). In such a scenario, the System Integrity and Protection Schemes (SIPS) plays important role in maintaining a secure, reliable grid and assists in effective grid management in India during conditions severe than (N-1) contingencies, disturbances/occurrences. This paper discusses the operational experience of implementing SIPS schemes in India. The operational experience of two prime SIPS schemes, one in the Northern Regional (NR) part of India and another in the Western Regional (WR) part of India are presented in this paper. Utilization of synchrophasor/Wide Area Measurement Systems (WAMS) in understanding the behaviour of the grid during major contingencies in these regions and subsequent operation of SIPS to tackle them is also explained in brief. In order to assess quantitatively the reliability of SIPS, there has to be a set of performance indices. This paper proposes a procedure for evaluating the performance of SIPS. It highlights the method for calculating Dependability index (D), Security index (S) and Reliability index (R) for SIPS based on the actual operational field data of SIPS in the Indian context.