A fuzzy logic controller (FLC) with fast reference voltage generation to correct and regulate unbalance voltage in three-phase system is proposed. The compensation algorithm is not based on three-symmetrical component decomposition so the controller can yield a fast response that is essential in such a critical real time control work. The reference voltage is fed to the FLC , which is a robust closed loop controller. The proposed algorithm and control scheme of series active filter may correct and regulate unbalance voltage in three-system under different conditions of the utility supply.