Shutdown full feathering method for blade clamping failures appearing in large wind turbine generator

Abstract

The invention discloses a shutdown full feathering method for blade clamping failures appearing in a large wind turbine generator. The method comprises the following steps that pitch angles are monitored to judge whether blades are clamped, a current transformer provides brake torque, an impeller rotating speed is measured, whether full feathering is achieved or not is judged, the pitch angles aremonitored to judge whether the blades are clamped or not, the pitch angles of the three blades are monitored in real time, whether the maximum value of the difference value of the pitch angles of thethree blades exceeds three degrees is set for judging whether the blade clamping failure appears in a certain blade of a wind turbine generator impeller, when the blade clamping failure exists, a number of the failure blade and the pitch angle alpha of the clamped blade are recorded, the preset variable pitch rate is used for enabling the two non-clamped blades to the designated pitch angle betain a full feathering manner, and continuous full feathering is stopped; and due to the shutdown full feathering method for the blade clamping failures, borne loads of a hub, a spindle, a main bearing,a bearing pedestal and other key parts in the shutdown process can be effectively reduced, and the unit design cost is further reduced.

Description

technical field [0001] The invention relates to the technical field of wind power generation, in particular to a method for feathering a large-scale wind turbine when a blade is stuck at shutdown. Background technique [0002] Blade stuck is a fault condition that needs to be considered in the design load calculation of wind turbines. For a traditional wind turbine with three blades, when a certain blade is stuck (occurs in the propeller state) and cannot complete the normal pitch change action, the unit needs to complete the feathering through other normal blades to reduce the impeller speed and complete the shutdown. . If it continues to operate with faults, the harmful load caused by the aerodynamic imbalance of the three blades will have a huge impact on the operating life of the unit. [0003] Large impeller diameter (extra long blades) is the development trend of modern wind turbines. The traditional strategy of feathering the blades to complete shutdown by changing...

AI Technical Summary

Problems solved by technology

This method has a certain effect on small wind turbines, but for modern large wind turbines (especially offshore wind turbines) with super long and overweight blades, the simple direct continuous feathering method is effective no matter what pitch rate is used. May cause excessive loads on critical components

Because as long as there is a feathering action, the aerodynamic imbalance between the blades will change, and the goal of reducing the shutdown load can not be fully achieved by only changing the pitch rate to complete the feathering shutdown

There is another flaw in the method provided in the patent: the key data that determines the pitch rate - the yaw bearing load, is calculated

Images