Research on the harmonic currents rates for the exchanged energy of unified distributed power flow controller

The energy exchange between series and shunt converters is the basis for powerful functioning of unified distributed power flow controller, which can be realized through 3rd harmonic current. In this paper, based on established equivalent network controller system, influence additional loss caused by current line transmission capacity analysed. mathematical relationship neutral point voltage transformer constructed, it simplified according to different currents. By analysing network, found that there a contradiction improving output efficiency single-phase converter reducing insulation transformer. constraint conditions are simulated advanced digital system simulator. Finally, method obtaining economical safe value range summarized, provides theoretical reference device parameter design.