Operational experience and performance evaluation of some of the system integrity and protection schemes

An Indian power system is characterized by a conglomeration of ultra-high voltage AC and DC, multi-terminal DC, and extra-high voltage AC transmission networks. It consists of a large distribution network across the country along with conventional generation having Ultra-Mega Power Plants (UMPP) and increasing penetration of Renewable Energy Sources (RES). The System Integrity and Protection Schemes (SIPS) play an important role in maintaining a secure and reliable grid and assists in effective grid management during severe power system contingencies. This paper presents the operational experience of some SIPS implemented in India along with their performance evaluations. The operational experience of three important SIPS, one in the Northern Regional (NR) grid and another two in the Western Regional (WR) grid of India are presented. The drawbacks in existing SIPS are pointed out and an algorithm is proposed to overcome these drawbacks. The performance and effectiveness of the proposed algorithm are evaluated by simulation studies on the 39-bus New England system embedded with an HVDC link in MATLAB/Simulink. Simulation results consummated confirm the authenticity of the scheme in preserving system integrity. Results are validated using Electrical Transient Analyzer Program (ETAP), which is a very powerful design and analysis tool and has an extremely user-friendly interface.