A damped harmonic composite control algorithm on transformerless shunt hybrid active power filter

Whereas transformerless shunt hybrid active power filter (TLS-PHAPF) is a novel topology of APF and a novel control strategy, it was provided to improve the quality of power system. Firstly, a control algorithm of dampen harmonic on APF based on voltage harmonic detection was proposed. Secondly, for the purpose of compensating both the load current harmonic and damping the grid voltage harmonic, this control algorithm was added to the current compensation APF to form a composite control strategy, where the load current and the grid voltage were feedback signals. Thirdly, all the proposed methods were validated by simulations and experiments. Moreover, the simulation and experiment results show that the proposed method can eliminate the series resonance produced by the interaction between the passive filter and the power grid, and meanwhile prove the feasibility of the control algorithm and the stability of the system.