Detecting Low Frequency Oscillations through PMU-based measurements for Indian National Grid

Indian National Grid formed with the connection of Southern Grid to the rest of India in the last phase on December 31, 2013 ushered in having improved frequency regime of operation as well as large inter-regional power transfer for optimal operation. But problems of Low Frequency Oscillations continued to be observed in several parts. Wide-Area Monitoring System with large-scale deployment of Phasor Measurement Units, made it possible to detect such oscillations at specific locations and evolve remedial measures to be undertaken. Under long-term strategy investment-oriented strengthening of transmission system is the choice. But to deal with such problems for day-to-day operation, tuning or retuning of Power System Stabilizers, controllers associated with Flexible AC Transmission Systems and HVDC Systems, etc. are considered as the best option. Commensurate Regulatory Framework too is expected to be made for handling such issues from the point of view of Plant-Grid Interaction.