This paper presents a method and design of the harmonic filters for adjustable speed drives. Power consumption of harmonic drawing load is an increasing concern for cost conscious facility managers and engineers. The proposed system has the function of voltage stability, and harmonic suppression. This work presents a method capable of designing filters to reduce harmonic distortion and correct the power factor. The optimization process considers the discrete nature of the size of the element of the filter .The simulation results of the system have been carried out with MATLAB 10.