Document Type : Original Article
Department of Electricity, Mahmudabad Branch, Technical and Vocational University, Mahmudabad, Iran
Department of Electricity, Mulla-Sadra Ramsar Branch, Technical and Vocational University, Ramsar, Iran
Nuclear Science and Technology Research Institute, Tehran, Iran
Instability of voltage is a problem that has been occurring in recent years due to excessive exploitation from equipment and an increase in demand for load across the distribution system. Shortage of the reactive power in the power networks, especially distribution networks, pushes the system toward voltage instability and leads to voltage drop as well as voltage fluctuations in the feeder. One of the potential solutions for compensation is to install thyristor switched capacitor (TSC). Although TSC can reduce the total costs of compensation, the static error will reduce compensation. For this purpose, an active power filter (APF) can be applied to resolve errors resulting from TSC due to features of continuous compensation and quick dynamic response. In this research, the combined method was presented, including TSC and APF of a controllable active power injection and with appropriate switching based on the study of voltage drop in the radial distribution networks and improvement of power quality. The suggested model was executed by MATLAB software, whereby results of improvement and provision of the stability conditions (dynamic and static) of voltage and current were observed.