Fuzzy Logic-Based AVC Relay for Voltage Control of Distribution Network with and without Distributed/Embedded Generation

Voltage control is considered one of the basic operational requirements of electrical power systems both at distribution and transmission levels. The most popular voltage control equipment includes On-Load Tap Changer (OLTC) transformer controlled by Automatic Voltage Control (AVC) relay, which is mostly used in 11 kV networks. In recent years, a growing number of distributed/embedded generators are connected to distribution networks. Conventional AVC relay usually equipped with compounding whose setting are chosen to compensate for the voltage drop along the feeder(s) emanating from source substation. However, the integration of Distributed/Embedded generators (DGs/EGs) including wind farms into distribution systems causes voltage regulation problems due to the interference with the performance of AVC relay. Therefore, the development of a new voltage control scheme of supply system with DGs/EGs is required. This paper presents an attempt to design an AVC relay based on Fuzzy Logic. The structure of the proposed Fuzzy Logic based-AVC relay is presented and the results that show its performance with and without integrated distributed generation into distribution network are also presented and discussed.