Water and Energy International

To keep pace with increased generation, UHV transmission system is being strengthened by POWERGRID to meet the power transfer requirements from generating station to load centers. Out of the planned generation capacity, a major chunk of about 34600 MW in Central/Eastern part and Northern/North Eastern part of India is expected to be installed in 12th plan owing to concentration of coal and hydel energy resources in these pocketed locations. As the loads are concentrated in the Northern and Western/Southern part of the country, a strong, reliable and long transmission network is required to transfer the generated power from one end to the distant load centers located at the other end. To transmit such bulk power over long distances, India may need to migrate to 1200 kV AC. To be future ready POWERGRID took a step forward in unique public private partnership (PPP) model to build a 1200 kV National Test Station (NTS) indigenously at BINA Madhya Pradesh, India in association with Indian Manufacturers. Experimental studies are being carried out at 1200 kV NTS to validate/finalize the parameters of 1200 kV Transmission network. In this regard, the knowledge gained from various system studies related to 1200 kV shall be helpful in fine tuning the technical parameters for future commercial projects.

Transient Recovery Voltage (TRV) of Circuit Breaker is a decisive parameter that limits the interrupting capability of the Circuit Breaker. As the TRV parameters for 1200 kV circuit breaker cannot be extrapolated from the lower voltage system, transient studies are to be carried out. In this paper, results of the TRV studies for typical 1200 kV Indian system are discussed. The simulation has been carried out using EMTP-RV software for determining the TRV parameters associated with Terminal Fault test Duties, Transformer Limited Fault (TLF), Short Line Fault (SLF), Out-of-Phase, Capacitive Current Switching, Reactor Terminal Fault cases etc.