Meeting Power Challenges with TCSC and Next Generation TCSC: SPLIT TCSC

Abstract

The electricity demand is continuously increasing due to population growth and development. There is a lack of generation and transmission facilities, so the existing system is used to transfer more power to meet the rising power demand. This causes overexploitation of the present power system and gives rise to stability problems. The power transfer capacity of the existing transmission lines can be increased by using fixed capacitors by varying the impedance of the transmission lines, but they have associated SSR problems. In this situation FACTS devices TCSC are used to control power flow in the system. TCSC mitigate power oscillation, stability problems and various power quality problems like voltage sag and voltage swell created due to disturbances or faults. In the proposed work the TCSC is used to increase the power flow capacity of the system without the need for investment in new lines and systems. The active power transfer with different controllers is discussed. The two modules of TCSC with different ratings are taken and analysed. Then there are some problems in ordinary TCSC too. On tuning the ordinary TCSC in the critical region of the reactance characteristic curve there is observed a large gap of reactance at both the inductive and capacitive critical regions. Because of the large elapse/gap of reactance in this region small change of power demand is not possible in the power system which reduces the flexibility of the power system, and it becomes rigid. These challenges of ordinary TCSC are met here by the next generation device of TCSC: Split TCSC in the power system. Split TCSC tunes the critical region reactance with many firing points and hence elapse of reactance is very small which allows for fine tuning of power flow over the transmission line thus mitigating the problems of ordinary TCSC. Split TCSC includes all the other benefits of ordinary TCSC such as increased power flow, stability improvement, damping oscillations, and mitigating SSR as it belongs to the family of TCSC. Thus, in the proposed work the power challenges are met using TCSC and Split TCSC.