Wind power plant low voltage ride through control method

Abstract

The invention discloses a wind power plant low voltage ride through control method, and particularly relates to a control method of a system and a device having a wind power plant low voltage ride through function. A basic principle of the wind power plant low voltage ride through control method is as follows: a three-phase current and voltage of an end, which accesses to a grid, of the wind power plant are measured, and equivalent impedance of the grid is calculated, so that a modularization impedance array which can be adjusted quickly is constructed; and the impedance array is connected with a high-speed circuit breaker in parallel and then is in series connection between a wind power plant converging wire and a boosting transformer incoming circuit breaker, judgment of generation of low voltage is completed within 2-4 milliseconds, the time point of a voltage sine wave zero crossing point is calculated, the high-speed circuit breaker completes a disconnection motion at the zero crossing point, the time of the low voltage judgment and the circuit breaker motion is not more than 12 milliseconds, access in series with a impedance array with the equivalent impedance of the grid is realized, and wire concentration voltage of the wind power plant is maintained to be unchanged.

Description

technical field [0001] The invention relates to a low-voltage ride-through control method of a wind farm, in particular to a control method of a system and a device with a low-voltage ride-through function of a wind farm. Background technique [0002] With the rapid development of wind power generation in recent years, the proportion of wind power in power supply has also increased rapidly. The resulting problems have also attracted widespread attention. Especially after the power grid fails and the voltage drops, if the wind turbines are disconnected one after another, the system will be temporarily unstable and may cause partial or even complete system failure. Therefore, Power grid companies have put forward certain requirements for wind turbines to be connected to the grid. The low voltage ride-through (LVRT) capability is a mandatory standard or specification that wind turbines or wind farms must be able to meet. [0003] The biggest difference between grid-connected w...

AI Technical Summary

Problems solved by technology

Therefore, the program is still at the stage of theoretical research and cannot be practically applied to wind farms or wind turbines