An electromechanical active harmonic filter

In this paper, a new electromechanical active harmonic filter is proposed. The proposed electromechanical harmonic filter is essentially a rotating synchronous machine with suitable modification to its field excitation circuit. It is shown that by injecting: 2/sup nd/, 4/sup th/ and 6/sup th/ harmonics currents into the field winding, 5/sup th/ and 7/sup th/ harmonic currents are generated in the stator winding. 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. Simulation and experimental results are presented to demonstrate the effectiveness of the proposed harmonic compensation method. This method is cost effective since it can be applied to existing standby generators in commercial and industrial plants with minimal modification to the excitation circuit.