731 / 2019-04-26 09:28:35

The Influence of the Grid Overvoltage on Fully Rated Converter Wind Turbine and an HVRT Control Strategy Based on Reactive Current

Fully Rated Converter (FRC),High Voltage Ride Through (HVRT),Permanent magnet synchronous generator (PMSG),, DC Link Overvoltage

Permanent magnet synchronous generator (PMSG) with fully rated converter (FRC) has been a rising solution to variable speed wind generation. The grid connected FRC wind turbine may be under the impact from grid overvoltage, which can lead to a compulsive and constant DC link overvoltage, threatening the safety of the DC link capacitor and the electronic switches. This paper studies the influence of the grid overvoltage on FRC wind turbine and its mechanism, and based on which, designs a control strategy of the reactive current of grid side converter to reduce the level of the DC overvoltage to realize high voltage ride through (HVRT). The active current fluctuation is introduced into reactive current reference to enhance the dynamic performance of the DC link voltage. The control strategy is simulated using DIgSILENT PowerFactory software and the results prove to be effective.