Voltage control of Tenaga Nasional Berhad 132 kV transmission system using shunt capacitors

Abstract

Power System, over many years, has undergone dramatic revolution both in technological as well as structural aspects. With the ongoing growth of the electric utility industry, including deregulation in many countries; numerous changes are continuously being introduced to a once predictable system. In an attempt to maximally use the transmission system capacities for economic transfers, transmission systems are being pushed closer to their stability and thermal limits, with voltage instability becoming a major limiting factor. Insufficient reactive power support affects the reliable operation of electric power systems leading to voltage collapses as observed by the 2003 National blackout. As a quick corrective action, Tenaga Nasional Berhad (TNB) has aggressively installing Capacitor Banks at its selected 132 kV substations with the intention to improve the voltage profile and the reactive power across the transmission system. The Capacitor Banks are installed in receiving substations, switching substations and substations near an inductive load. This research is basically to analyze the overall performance of the affected system with the installation of the Capacitor Banks specifically at 132 kV Substations. The performance analysis was made based on the comparison of initial performance prior to the Capacitor Banks installation and the performance of the system after the installation of the Capacitor Banks using PowerWorld Simulator. The research also covers on the issue of possible optimal location of the Shunt Capacitor Banks and the improvement of the affected system. The simulation was successful and the simulation results obtained reflected the functions of capacitor banks in voltage control of TNB transmission networks. Other possible locations for the capacitor banks installation managed to be identified through the simulations conducted.