I.J. Intelligent Systems and Applications, 2013, 10, 35-42 Published Online September 2013 in MECS (http://www.mecs-press.org/) DOI: 10.5815/ijisa.2013.10.05 Copyright © 2013 MECS I.J. Intelligent Systems and Applications, 2013, 10, 35-42 Design and Implementation of Three Phase Unbalanced Voltage Motor Controller M. A. A. Mashud Department of Applied Physics, Electronics and Communication Engineering, Islamic University, Kushtia -7003, Bangladesh E-mail: ms.mashud@yahoo.com S. C. Barman Department of Applied Physics, Electronics and Communication Engineering, Islamic University, Kushtia -7003, Bangladesh E-mail: scb_iuk@yahoo.com M. R. A. Bhuiyan Department of Applied Physics, Electronics and Communication Engineering, Islamic University, Kushtia -7003, Bangladesh E-mail: mrab@yahoo.com Md. Serajul Islam Department of Medical Physics and Biomedical Engineering, Gono Bishwabidyalay, Savar, Dhaka, Bangladesh E-mail: islammdserajul8@gmail.com. Abstract— A state-of-the-art-technology was used to design the unbalanced three phase motor controller. The fluctuation of line voltage has been questioned in recent times due to the use of heavy powered machine with three phases. This paper is focused on deriving a control scheme to drive a three phase motor that could be used in industry or households. The very simple circuitry has been employed in this design. To do this, extensive MATLAB analysis and PSpice software was conducted in order to optimize the control system and finally the results are practically verified. Index Terms— Industry, Line Voltage, Three Phase, Unbalance, Spark And Damage I. Introduction Fluctuations of line voltages are of special attention now-a-days. A need for reasonable power is required to smoothly operate electrical and electronic appliances. Quite often it happens that line voltages of some phases go down to a low level or high level. Therefore the line voltage becomes unbalanced. A large number of machines used in industries such as garments sectors, agricultural industry, cement factory, ceramic or glass factory, cold storage, dying sectors and so on are needed balanced voltage. For these erratic conditions of line voltages the valuable machines becomes damaged. Besides sometimes it makes sparking and makes serious problems in industry such as burning. Under such erratic conditions of line voltage, in our country re-wireable fuse or miniature circuit breaker are normally used to protect different households from under and over-voltage conditions is explained in S. Islam et.al, [1]. Considering this factor, a protective device like over-voltage and over-current with time delay unit has been developed for ensuring a dependable and an effective protection to small households in year 1992 that explained in S. Islam et.al, [2]. This system is relatively slow and designed in transistor based. For the better performance another device has been developed to protect households in year 1994 which explained in S. Islam et.al, [3]. The operation speed of this device is better but it was designed in transistor based. In year 2011, another attractive device has been developed for single-phase line to protect electronic appliances from over-load which explained the author M.A.A. Mashud et.al, [4]. In this design transistor module has been replaced by IC module and use Hall Effect principle. In year 2012, the author M.A.A. Mashud et. al, [5] explained single phase line voltage controller using microcontroller. In this design all electronic components and ICs has been replaced by using a microcontroller. But all the above designs are for single phase line voltage controller. Now, the author developed a three phase unbalanced line voltage controller. Easily available components and simple circuitry, the system should be beneficial in providing low-cost.