Reactive power control method in wind farm

Abstract

The invention discloses an in-farm reactive power control method for a wind farm. The method includes the steps of evaluating reactive output capacity of a wind farm reactive source; according to the results of evaluation, judging whether or not the wind farm is under emergency running; if not, preferring reactive output of doubly-fed wind turbine units; if yes, preferring adjustment of reactive power of a reactive compensator; distributing reactive powers of the doubly-fed wind turbine units according to the judgment above. The method has the advantages that in-farm reactive voltage control for the wind farm is achieved, operational safety and stability of a power system during connection of large-scale wind power is guaranteed, grid safety is guaranteed, and on-grid energy of new energy resources is increased.

Description

technical field [0001] The invention relates to the technical field of reactive voltage control in the process of new energy power generation, and in particular to a reactive power control method in a wind farm. Background technique [0002] Most of the large-scale new energy bases generated after my country's wind power enters the stage of large-scale development are located in the "three north regions" (Northwest, Northeast, and North China). Large-scale new energy bases are generally far away from the load center, and their power needs to be transmitted to load center for consumption. Taking Gansu Power Grid as an example, as of April 2014, the installed capacity of grid-connected wind power in Gansu Power Grid has reached 7.07 million kilowatts, accounting for about 20.2% of the total installed capacity of Gansu Power Grid (35 million kilowatts), becoming the second largest after thermal power. The main power source; the installed capacity of photovoltaic power generation...

AI Technical Summary

Problems solved by technology

At present, the low-voltage tolerance of the wind turbine itself is very limited. At this time, the wind turbine often adopts the method of automatic cut-off for its own protection, which causes the active power imbalance of the system and affects the stability of the system; at the same time, the asynchronous generator does not have the ability to maintain and adjust The ability of the machine terminal voltage level, also absorbs reactive power from the system during operation, so the problem of voltage stability is more prominent

Due to the mutual influence between the voltage and frequency of the entire power grid in the AC network system, the large changes in wind power output in Jiuquan area will inevitably cause voltage and frequency fluctuations in the entire system, resulting in further expansion of the accident

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