Improving The Voltage Stability Of The Power Transmission System In Sierra Leone Using TCSC

The increase of the electric power demand in Sierra Leone has brought a concern for an economically improved power system and ways of its operation in the country.The maximum capability of the power system thus exploited by means of employing the operation of FACTS devices.In this Modern world of our days' development of power electronics devices/switches has made a tremendous reduction in the cost of FACTS devices and therefore,application of FACTS devices especially in transmission and distribution network is more economical.However,the economic consideration limits the installation of FACTS controllers in all of the buses or transmission lines in a system.Therefore,several methods for finding the optimal location of FACTS in the power system thus developed.This thesis focuses on voltage improvement of the power transmission system in Sierra Leone using the Thyristor Control Series Compensation(TCSC).An overview of this device is given in the below chapter.Power flow solution is developed in MATLAB Simulink program with the use of power system Analysis Toolbox(PS AT)that uses Newton Raphson iteration method to simulate an existing major 7-bus system;161KV transmission network of Sierra Leone.The device at first tested on the IEEE 5-bus system and the results achieved were observed and recorded.Voltage drops were noticed at some weak buses when TCSC is incorporated.With the inclusion of TCSC,the new voltage magnitude is obtained for each bus,and consequently a significant reduction in the system losses.After observing the operation of the device on the standard IEEE model,hence incorporated into the main case study.In this way,the efficiency of the system is enhanced while the prolonged and frequent voltage collapse in the transmission network is minimized.The raw data used in this research was obtained from the power system analysis unit in Sierra Leone known as EGTC(Electricity Generation and Transmission cooperation).