Comprehensive protection system and method for wind power plant current collection line and box-type substation

Abstract

The invention relates to a comprehensive protection system and method for a wind power plant collector line and a box transformer substation, and the method comprises the steps: setting a grid-connected protection device to be installed at a grid-connected point of the collector line, and collecting the three-phase current and three-phase voltage of the grid-connected point; setting a transformerside protection device to collect the high-voltage side three-phase current and the low-voltage side three-phase current of the transformer, and judging whether the corresponding transformer has a fault or not; sending the three-phase current of the high-voltage side of the transformer to a communication host; and enabling the grid-connected protection device to calculate the difference between the sum of the three-phase currents of the high-voltage side of each transformer and the three-phase current of the grid-connected point and judge whether a fault exists or not. According to the invention, the problem of difficulty in setting the protection constant values of the current collection circuit and the box-type transformer is solved, the problem of override trip is effectively avoided, and the selectivity, the quickness and the sensitivity of relay protection are considered. Fault points can be safely and quickly removed, accident expansion is avoided, it is guaranteed that power generation facilities of normal lines can continue to generate power, and benefits of power generation enterprises are increased.

Description

technical field [0001] The invention relates to the technical field of power protection, in particular to a comprehensive protection system and method for a power collection circuit and a box transformer of a wind power plant. Background technique [0002] With the continuous expansion of wind power generation capacity, the fault characteristics of transmission network are very different from conventional transmission lines. Its special fault characteristics make the relay protection device unable to calculate according to the traditional fixed value setting method, and also cannot meet the requirements of relay protection. of selectivity, quickness and sensitivity. In the process of power generation, the electric energy of the wind turbine is converted into 50Hz voltage with the same frequency as the power grid through the inverter of the tower, and then boosted to 10kV or 35kV through the box-type substation (hereinafter referred to as the box-type transformer), and then c...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the problems existing in the prior art, the present invention provides a comprehensive protection system and method for wind power plant collector lines and box-type transformers, which solves the problem of difficult setting of protection settings for collector lines and box-type transformers, and effectively avoids skipping trips problems, and take into account the selectivity, quick action and sensitivity of relay protection

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