©International society of academic and industrial research www.isair.org International Journal of Academic Research in Applied Science 2(7): 1-9, 2013 ijaras.isair.org IJARAS Tuning under Load Tap Changer Controller by using Artificial Bee Colony Algorithm for Voltage Control Mostafa Abdollahi 1 , Farzad Hosseinzadeh 2 , Saeid Ghasrdashti 3 , Hassan Saeidinezhad 4 1,2,3,4 Department of Electrical Engineering, Bandar Lengeh Branch, Islamic Azad University, Bandar Lengeh, Iran mostafa.bastaki@gmail.com, Fhosseinzadeh05@gmail.com, ss344200@yahoo.com, Saeidinezhade@gmail.com Abstract Tap-changer transformers can contribute to power systems voltage stabilities as well as voltage profile enhancement and control. In this regard, application of under load tap changer (ULTC) transformer for voltage control is addressed in this paper. The controllers of the proposed ULTC are tuned by using an optimization technique namely artificial bee colony (ABC). Optimal tuning of ULTC controller leads to fast and stable response following large disturbances such as line outage. Simulation results demonstrate the ability and effectiveness of ULTC in voltage control and stability improvement. Keywords Under load tap changer transformer; artificial bee colony; voltage control; large signal disturbances