Optimizing Power Quality and Efficiency of a Distribution Substation through Static Var Compensators: A Case Study of the 132 kV Qasimabad Grid Station, Pakistan

Abstract

The Qasimabad Grid Station has lost its efficiency due to increasing electricity demand and the aging of its infrastructure. This has resulted in frequent outages, overloading of transformers, degradation of the power factor, and bus voltages that are close to the minimum allowable values. To evaluate the performance of the grid, a power flow study was performed using the Electrical Transient and Analysis Program (ETAP) in accordance with the regulatory framework of the National Electric Power Regulatory Authority (NEPRA). The main goal of this study was to improve the performance of the grid system through the integration of Static Var Compensators (SVCs) in the modeled network. The first step in the research was to analyze system limitations to determine the reactive power needs of the system for proper SVC location and sizing in the network. This stage required data gathering and analysis during both high load and low load periods, paying particular attention to the number of transformer overloads experienced in June 2023, as well as underloads experienced in December 2023. The results further strengthened the findings of previous studies that SVCs are beneficial in improving grid reliability by maintaining nominal bus voltages, reducing transformer loading, and correcting the power factor.