Indian Power System is growing with a rapid pace and another 100000 MW is planned to be added in next 5 year plan. With the result, the transmission & distribution is increasing many fold. The optimal use of existing infrastruclllre needs to be done in order to contain investment. It is therefore necessary to load the existing lines to optimal capacity rather than providing the additional corridor where ever it is not absolutely necessary. Some times it is necessary to provide additional corridor in order to maintain system's reliability and availability. Overloading of subsystem in a power system some times may pose stability issues, which may lead to unwanted tripping, equipment failures which will result long repair/replacement cycle and heavy revenue losses. Under these conditions, to ensure economical and reliable operation of the grid, power through the lines should be controlled within their capabilities. Control of power in AC network requires special technology to be implemented on case to case basis. Operating efficiency of electric transmission system can be improved by using appropriate FACTS devices. Phase shifting transformer is one of the FACTS family, which can be used for power control in a network. For demonstrating the ability of the phase shifting transformer in regulating the power flow in an alternate transmission network, various cases involving simulation of Maharashtra zone, Uttar Pradesh zone, a part ofAndhra Pradesh zone and inter regional power control of the Indian grid are considered. From power flow solution, various overloaded lines and the alternate underloaded lines are identified. Different cases are simulated to regulate the power using phase shifting transformer. By introducing phase shifting transformer in to the actual network of the Indian Grid, power flows in the area of interest are re validated and application of PST is justified.
Phase shifting transformer, power flow control, over loaded lines, PSSlE
