A load reduction control method for wind turbines under gusts

Abstract

The invention provides a wind turbine generator set load reduction control method under the condition of a gust. The wind turbine generator set load reduction control method under the condition of the gust comprises the following steps that firstly, the wind turbine generator set is made to be in a direct torque control mode; secondly, the values of the rotating speed change rates d omega of the impeller of the wind turbine generator set are compared with set values; thirdly, torque raising control is conducted, and the electromagnetic torque of the wind turbine generator is controlled according to (T electromagnetic+ delta T1); fourthly, torque reducing control is conducted, and the electromagnetic torque of the wind turbine generator is controlled according to (T electromagnetic+ delta T1). According to the wind turbine generator set load reduction control method under the condition of the gust, because the rotating speed change rates d omega of the impeller of the wind turbine generator set are compared with the set values in real time, when the rotating speed change rates d omega of the impeller exceed the set values and namely, the gust comes, torque raising or reducing control operation is conducted on the electromagnetic torque of the wind turbine generator set according to set conditions, the wind turbine generator set is made to deviate from an original power curve for a short time, the main body power curve of the wind turbine generator set is not influenced, and the load reduction effect is achieved; and because the electromagnetic torque of the wind turbine generator set is adjusted in time, sudden reducing and sudden raising of the rotation speed of the impeller are restrained, and the stability of a control system is improved.

Description

technical field [0001] The invention relates to the field of wind power generators, in particular to a method for controlling load reduction of wind power generators under gusts of wind. Background technique [0002] At present, the power control method of wind turbines is generally direct torque control, that is, the wind turbines are based on the relationship T 机械 -T 电磁 =0, for impeller speed ω is controlled, where T 机械 is the mechanical torque absorbed by the impeller, T 电磁 is the electromagnetic torque output by the wind turbine. In theory if T 机械 -T 电磁 =0, the impeller speed ω constant; if T 机械 -T 电磁 >0, impeller speed ω rise; if T 机械 -T 电磁 <0, the impeller speed ω decline. When the wind speed is below the rated wind speed, through the maximum wind energy capture control and T 电磁 control, constantly approaching the relation T 机械 -T 电磁 =0 to meet the requirements of the reference power curve; when the rated wind speed is above, T 电磁 Constant outpu...

AI Technical Summary

Problems solved by technology

However, for the working conditions with rapid changes in wind speed and large turbulence, the impeller speed controlled by this control method ω Affected by the wind speed, there will be large fluctuations, which will increase the mechanical fatigue of the wind turbine, especially the transmission parts such as bearings, and reduce the service life of the wind turbine

In particular, when the wind speed is high and there is a greater gust of wind, the wind turbine is prone to overspeed and other phenomena, which affects the safety of the wind turbine.

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