Method by utilizing doubly-fed generator to realize high-voltage ride through of wind power generating set and system thereof

Abstract

The invention relates to a method by utilizing a doubly-fed generator to realize the high-voltage ride through of a wind power generating set and a system thereof. The method comprises the following steps that: terminal voltage, reactive power and active power of the wind power generating set are instantly monitored; when the terminal voltage exceeds 1.1 times of rated voltage, a reactive power order QOUT is calculated; and the doubly-fed generator is controlled to output correspondent inductive reactive power according to the QOUT. The system comprises an electric energy quality module, a set main controller program logic controller (PLC), a wind power converter and the doubly-fed generator. The method is a coordinated control method of inductive reactive power by adopting the terminal voltage of the wind power generating set as a control target, so the terminal voltage of the wind power generating set can satisfy the work requirement of electrical devices inside the generating set, the normal continuous running of the wind power generating set can be guaranteed when the voltage of the electric network is increased to be more than 1.3 times of the rated voltage, and the high-voltage ride through of the doubly-fed wind power generating set is realized by utilizing the decoupling characteristics of the active power and the reactive power of the doubly-fed generator.

Description

technical field [0001] The invention relates to the technical field of wind power generation, in particular to a method and system for realizing high-voltage ride-through of a wind turbine by using a doubly-fed generator. Background technique [0002] Wind energy is random and uncontrollable, so the output power and voltage of wind turbines also fluctuate randomly. With the expansion of the capacity of a single wind turbine in my country and the increase in the proportion of the total installed capacity in the national grid, the scope of influence of wind turbines on the grid when they are connected to the grid is gradually expanding from the local area, and the degree of influence is also deepening. [0003] In view of this background, the State Grid Corporation of China puts forward the requirement of high-voltage ride-through for the operation capability of wind turbines, that is, when the voltage of the grid-connected point of the wind farm is within the range of 0.9-1.3...

AI Technical Summary

Problems solved by technology

[0005] The first one: increasing the operating voltage drop of electrical equipment greatly increases the cost of electrical equipment, thereby increasing the operating cost of the unit itself

On the other hand, if the internal electrical equipment of the wind turbine is replaced with electrical equipment that can withstand 1.3 times the rated voltage, it will consume a lot of manpower and financial resources

[0006] The second method: the traditional grid-connected point voltage control method of wind farms is to adjust the grid-connected point voltage by deploying reactive power adjustment equipment such as SVC and SVG, but such equipment is expensive and difficult to achieve dynamic deployment, which is not conducive to Dynamic coordinated control of grid-connected point voltage for wind farms

On the other hand, the wind farm is closely connected with the power grid. Due to the influence of the operation of the large power grid, it is difficult to effectively change the voltage of the grid-connected point of the wind farm.

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