In order to meet the reactive power demand of new energy power stations, an LC series filter converter is proposed in this paper. Taking the three-phase 380 V / 30 kW grid converter as an example, compared with the traditional L and LC filter structure, the proposed converter structure can reduce about 71% of the original converter system DC voltage and release 12% of the active capacity while maintaining the converter output reactive power capacity. And the efficiency is improved by 6% when compared with the original filter structure. In addition，based on the discrete state model of LC converter, a state control method based on LC series filter type converter is proposed, which effectively improves the system damping of LC series filter at the resonant frequency. Finally, a simulation model of LC converter is established in PSIM to verify the advantages of LC filter converter and the feasibility of the state feedback control strategy.