Synchronous interconnection between two different capacity regions — A case study

400 kV Rourkela-Raipur double circuit 412 km long inter-regional link between Eastern and Western Regions has been established for operation of both the regions in synchronism for the first time in India. This paper briefly discusses the results of the various studies carried out to establish the feasibility of synchronous interconnection between these two regions having different capacity. Major benefits of synchronous interconnection are also deliberated. Further, to enhance the power transfer capacity of this long inter-regional link with reliability and security, 40% Fixed series compensation along with 5-15% variable compensation (Thyristor Controlled Series Capacitor) was provided to maintain system integrity under different operating conditions. Results of dynamic studies carried out to determine the optimal degree of compensation, both fixed and variable types, are also presented.