Wind power converter control method, power equipment control device and converter

Abstract

The invention discloses a wind power converter control method, and provides a wind power converter. The wind power converter comprises a grid-side converter, a machine-side converter, a grid-side controller and a machine-side controller, wherein the grid-side controller controls the grid-side converter to adopt three-level unipolar wave generation, and the machine-side controller controls the machine-side converter to adopt three-level unipolar wave generation. According to the wind power converter control method, three-level topology direct current bus voltage ripples can be reduced, the advantages that three-level topology network side current harmonics are small, the machine side voltage du / dt and the voltage peak are small are kept, and the cost and the size of the converter are not increased. Meanwhile, the invention further discloses a power equipment control device and the converter.

Description

technical field [0001] The invention relates to the field of wind power generation, in particular to a control method for a wind power converter. Background technique [0002] The increase of single unit capacity is one of the current development trends of wind turbines. With the increase of the capacity of wind turbines, the input and output currents are getting larger and larger, which leads to the increase of cable costs and problems such as "twisted cables". In order to reduce the current, It is necessary to increase the voltage level of the motor, converter and transformer of the unit, such as increasing from the commonly used 690V to 1140V and 3300V. For the voltage level of 1140V and 3300V, the wind power converter generally adopts a three-level topology, and the three-level topology can be used Power semiconductor devices such as IGBTs with lower voltage levels can also reduce input and output current harmonics, reduce voltage du / dt and voltage spikes applied to the ...

AI Technical Summary

Problems solved by technology

[0003] At present, the three-level topology generally adopts space vector modulation or carrier layer stacking. It will generate a large current three times its operating frequency at the midpoint of the busbar, and the positive and negative busbar voltage ripples will also be relatively large, especially when the motor operating frequency is low and the power factor is low, the busbar voltage ripple will be large. This will reduce the life of the bus capacitor, and the triple-frequency bus ripple caused by the machine-side converter will cause inter-harmonics on the grid side to pollute the grid and affect the stability of the grid-side converter

[0004] In the prior art, the bus voltage ripple is generally reduced by increasing the bus capacitor capacity or adding a balancing circuit, but these measures will increase the cost of the converter and increase the size of the converter

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