Design of Transformers for 60 kVA Automatic Voltage Stabilizer

This paper is a study of development of servo-controlled automatic voltage stabilizer (AVS) for application in industrial zones. These are most suitable for 24 hours continuous process plants where breakdowns due to fluctuation results in heavy financial losses occur. A stabilizer in this paper is unbalanced system because most of the industries used unbalanced load. A stabilizer in this paper has five main parts. They are variable autotransformer, buck-boost transformer, contactor, servo-motor and electronic control circuit. The main implementation of this paper is the design of variable autotransformer and buck-boost transformer. Three identical 20 kVA automatic voltage stabilizers are needed to get 60 kVA automatic voltage stabilizer. So, 20 kVA rating is designed. This stabilizer will operate within the fluctuation range from 130 V to 250 V.