In this paper, a new electromechanical active harmonic filter is proposed. The proposed electromechanical harmonic filter is essentially a rotating asymmetric air gap concentrated winding synchronous machine (AACWSM) with AC and DC excitation field. It is shown that the AACWSM with its unique design can be used to cancel the most dominant current harmonics of the adjacent nonlinear load. The filter is connected in a shunt manner between a nonlinear load and utility. This new AACWSM with its nonlinear current waveform can generate the nonlinear load required harmonics current. By proper control of the field excitation, the proposed electromechanical harmonic filter can compensate for the 5/sup th/ and 7/sup th/ harmonic currents in the electric power distribution system. In addition, 11/sup th/ and 13/sup th/ harmonics magnitudes are also significantly reduced. Analysis and simulation are presented to demonstrate the effectiveness of the proposed harmonic compensation method.