Reactive Power Control and Transmission Loss Reduction in Sudan National Grid Using SVC and TCSC

Abstract

Power systems operation becomes more important as the load demand increases all over the world. This rapid increase in load demand forces power systems to operate under heavily stressed conditions, near critical limits due to economic and environmental constraints. Flexible Alternating Current Transmission System (FACTS) devices are found to be encouraging in improving voltage stability limit of power systems. In this Dissertation steady-state model of Static VAR Compensator (SVC) and Thyristor Controlled Series Compensator (TCSC) for power flow studies has been represented and discussed in details. The SVC is used to control the voltage at which it is connected. In same manner model of TCSC is used to control active power flow of the line to which TCSC is installed. Sudanese national grid is undergoing changes as a result of constant power demand increase, thus stretching it beyond their voltage and thermal limit. This drastically affects the power quality delivered. Transmission systems should be flexible to respond to generation and load patterns, then incorporate this device in Sudanese grid to enhancement the performance. In addition optimal location and sizing of TCSC and SVC are considered for reducing line losses and improving voltage limit. The optimal locations of SVC and TCSC are chosen using line indices, Fast Voltage Stability Index, Novel Voltage Stability Index, Line Fast Stability Index and line index (FVSI, NVSI and LQP). Simulations are carried out using NEPLAN software. The results obtained showed the effectness of SVC and TCSC on voltage profile, power losses and power transfer through the line in the Sudanese national grid.