Apparatus for implementing low voltage cross-over of wind generator set

Abstract

A device for realizing the low voltage crossing of the wind generating set includes an energy storage device reactance transformer, an energy conversion device AC and DC convertor and protective devices thereof, and a bypass switch controlled by the fan main control system, wherein the primary edge of the reactance transformer is respectively electrically connected with a filter and a net side transformer, and the assistant edge is connected with the bypass switch, the AC and DC convertor and the protective devices in parallel. The voltage output end of the AC and DC convertor is connected with the DC voltage input end of the uninterruptable power supply. When the mains voltage falls, the bypass switch is broken, the energy stored in the reactance transformer is provided to the uninterruptable power supply through the AC transformer, to ensure that the uninterruptable power supply has ample electric energy to supply to key parts of all the subsystems, and realize the low voltage crossing, meanwhile, since the assistant edge of the reactance transformer provides power to the AC and DC convertor, the equivalent impedance is greatly advanced and the current is effectively restrained.

Description

technical field [0001] The invention relates to a device for realizing low-voltage ride-through of a wind power generating set. Background technique [0002] With the increase of wind turbine unit capacity, wind energy is becoming one of the energy sources widely used in power systems. In order to reliably supply power to the grid, wind turbines must strictly meet the grid access requirements. In particular, low-voltage ride-through (LVRT for short, the same below) usually requires that when the grid voltage drops within a predetermined range, the wind turbines cannot be disconnected from the grid, and the wind turbines must be able to provide reactive power during this process to support the recovery of the grid voltage. [0003] According to LVRT requirements, such as figure 1 It shows the relationship curve between voltage fluctuation and time. When the grid voltage drops to a certain level, whether the wind turbine can trip and how long to maintain the connection with ...

AI Technical Summary

Problems solved by technology

However, when the voltage drops, if the uninterruptible power supply is only used for power supply without the supplementary support of the follow-up power supply, due to the constraints of the UPS's own power supply capacity, it may not be possible to ensure that sufficient power is provided to all key components, and it is impossible to ensure Control the safe operation of the unit during the entire voltage drop

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