Energy Shaping Repetitive Control Technology for Shunt Active Power Filter

Active Power Filter (APF) is usually used to compensate the harmonic currents which are generated by the nonlinear load, and its compensation performance mainly depends on the estimation of APF mathematic model, instruction signal of harmonic currents and design of controller. Traditional control APF uses the average mathematic model, and PI controller and its instruction signal of harmonic currents is obtained by load harmonic currents. This paper adopts the energy shaping repetitive control technology to correct the output current waveform of three-phase three-wire shunt active power filter, Energy Shaping Control can guarantee APF system dynamic stability. Hamiltonian model of APF is built. Instruction signal of harmonic currents is obtained by PI controller of the voltage harmonic where APF is located, in this way, load harmonic currents are not necessary in the control process. The controller design procedure is analyzed in detail. Theoretical analysis and experimental results demonstrate the validity of the proposed method, the filtering performance is improved obviously.