1. Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang 621900, China;2. School of Automation, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
A space vector pulse width modulation(SVPWM)strategy and power distribution method of a three-phase three-port AC-DC converter are investigated, which can serve as an interface converter for stand-alone renewable power supply systems. The inherit power fluctuation from the new energy devices can be minimized by cooperation of the batteries and new energy devices. The topology of the converter is similar to that of a traditional T-type three-level AC-DC converter, with a partial-voltage capacitor on the DC side acting as the battery port. Single stage power conversion is established between the AC port and the DC output port, as well as between the AC port and the battery port. A modified SVPWM strategy for asymmetric three-level operating condition is obtained based on the traditional SVPWM strategy. By analyzing the power flow directions corresponding to different switching vectors, it is verified that power distribution between the two DC ports can be reached by adjusting working time of switching vectors. A closed-loop power distribution method is thereby established. The power range, current ripple and power density of the converter are discussed in detail. The simulation results support the theoretical conclusions and prove the high efficiency of the converter.
LIU Tingting, LIU Shizhao, HU Ronghua,et al.Power Distribution Method of Rectifier with Two DC Ports Based on Modified SVPWM Strategy[J].Automation of Electric Power Systems,2019,43(17):160-167.DOI:10.7500/AEPS20181218008Copy