Design of a Novel Islanding Scheme: Experiences With Lalitpur Power System, India
- Resource Type
- Conference
- Authors
- Bhui, Pratyasa; Basumallik, Sagnik; Singh, Manohar
- Source
- 2024 IEEE Texas Power and Energy Conference (TPEC) IEEE Texas Power and Energy Conference (TPEC), 2024. :1-6 Feb, 2024
- Subject
- Power, Energy and Industry Applications
Measurement
Time-frequency analysis
Islanding
Load shedding
Power system stability
Generators
Frequency control
blackout
islanding
under frequency load shedding
special protection scheme
stability
- Language
Creating a power island with generating plants and nearby critical loads during impending blackouts helps keep the generating plants online and supply critical loads. This paper presents experiences with designing a methodology to stabilize the frequency in a small island after disconnection from the main grid. First, the islanding region is selected based on historical data of local load and generation. Then, the threshold frequency is selected to island the region considering the control actions in the bulk transmission grid. Post-islanding under frequency load shedding is proposed in large blocks to restrict the frequency fall. Over-frequency load reconnection is done in smaller steps which helps in restricting frequency rise after load shedding and minimizing the difference between local load and generation. Over-frequency tripping of a few generators is done to avoid tripping of all generators. A novel metric is proposed to trigger generator tripping which is based on the expected time to reach a threshold frequency and requires less number of set parameters as compared to only frequency-based generator tripping. Finally, the method was tested with extensive simulations for Agra-Lalitpur region in the Indian Grid in PSS/E simulation environment and submitted to a competent authority for practical implementation.