Special tri-level full-power converter set for large power wind-driven generator

Abstract

The invention discloses a special tri-level full-power converter set for a large power wind-driven generator, which comprises four groups of tri-level rectifiers, and is characterized in that an electric grid-side converter is of two groups of tri-level inverters, the four groups of tri-level rectifiers are respectively connected with four groups of separated three-phase windings of a generator, two groups of tri-level rectifiers which are connected with two groups of three-phase windings with the phase difference of 180 degrees of the generator are connected with each other in parallel, the rectifier groups after being connected with each other in parallel are connected with each other in serial and are connected with two groups of tri-level inverters in parallel connection, and finally the rectifier groups are connected with the electric grid. Four groups of Vienna rectifiers are used for sharing the power, since the Vienna rectifier is of a tri-level converter, the harmonic wave and loss performance thereof are better than that of two-level converter; in addition, each group of Vienna rectifiers only requires three IGBT modules, and the traditional two-level converter requires six IGBT converters, so the reliability of the Vienna rectifier is high. Two groups of tri-level inverters are adopted at the side of the electric grid to be connected with each other in parallel, so the pulse of neutral point potential is neutralized by two groups of converters in parallel connection through the phase reversal design of the transformer.

Description

technical field [0001] The invention relates to the field of wind power, in particular to a special hybrid three-level full-power converter set for high-power wind power generators, which is mainly used in megawatt-level variable-speed wind power generators. Background technique [0002] Wind power is currently the clean energy with the most potential for commercial development, and it is also one of the renewable energy sources that my country focuses on. The current mainstream technical solution for wind power generation is the variable-speed fan technology, and in order to realize the variable-speed operation of the fan and the grid connection of the wind turbine, the power electronic converter is an indispensable core controller. Among the implementation schemes of various variable speed wind turbines, the full power wind power converter installed on the stator side of the generator is one of the important schemes to realize the variable speed and constant frequency cont...

AI Technical Summary

Problems solved by technology

Since the stator-side converter solution must handle all generator power, this causes many difficulties and high costs in the design and manufacture of the stator-side wind power converter

In particular, the current international stand-alone power of wind turbines has reached 5MW, and the power level above 5MW is being further developed. Therefore, higher requirements are put forward for the design and manufacture of wind power converters, while the existing single generator and single The technical solution of the converter can no longer meet this technical requirement

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