Control method and device capable of restraining overspeed of wind generating set

Abstract

The invention discloses a control method and device capable of restraining overspeed of a wind generating set. The method includes the steps that output parameters generated when the generating set runs are detected in real time, and pitch control over the generating set is carried out according to difference values between real time detection values of the output parameters and target controlling values; and when pitch control is carried out, the running state of the generating set is judged in real time, when it is judged that the generating set is in the overspeed state, an overspeed restraining control part is started, current pitch-control control parameters are adjusted, pitch control is carried out according to the adjusted control parameters, response speed of pitch control is adjusted to rapidly decrease the running speed of the generating set, or current pitch control is carried out. The device comprises a pitch control unit and an overspeed judgment and restraining unit. By means of the control method and device, overspeed of the wind generating set can be restrained, the running reliability of the wind generating set under the working conditions including the extreme gustiness is improved, and the beneficial effects of being easy to control, low in needed control cost, high in control accuracy and flexible in control are achieved.

Description

technical field [0001] The invention relates to the technical field of wind power generation, in particular to a control method and device capable of suppressing overspeed of a wind power generating set. Background technique [0002] Variable-speed constant-frequency wind turbines are commonly used in wind discharge units. This type of unit realizes the following process through the control of the converter and the pitch system: 1) In the variable speed range below the rated power, the wind turbines Operate with maximum energy capture; 2) When the rated power is reached, the wind turbine is controlled by pitch control to realize the constant power and constant speed operation of the wind turbine. At present, pitch control in wind turbines usually sends a pitch angle command to the pitch system through the main control system, and the pitch system drives the pitch motor to execute a given pitch angle after receiving the pitch angle command. According to the characteristics o...

AI Technical Summary

Problems solved by technology

[0003] The above-mentioned inherent hysteresis characteristics of the pitch system make it unfavorable for the timely control of the speed by the pitch control. When the wind turbine is facing extreme gusts, especially the large inertia wind turbine, it is very easy to cause wind speed to change too fast and the speed to rise rapidly At the same time, the response of the pitch control system is too slow, resulting in overspeed protection shutdown, which increases the ultimate load of the fan

When the above pitch control method is under extreme gust conditions, due to the hysteresis characteristics of the pitch system, the limit load will increase due to overspeed shutdown, and frequent overspeed shutdown will also reduce the reliability of wind turbine operation, which is not conducive to Stable operation of the fan

[0004] In order to solve the overspeed problem of wind turbines under extreme gusts and other working conditions, at present, it is usually at the design stage of wind turbines to increase the ultimate load by strengthening the structural design to ensure the structural strength of the wind turbines, but this type of method requires high costs. At the same time, it will increase the weight of the wind turbine, which is not conducive to the lightweight design of the wind turbine

[0005] Wind turbines are developing in the direction of high power levels and large wind rotor diameters, their weight and inertia are increasing, and large wind turbines are more prone to overspeed protection shutdowns under extreme gusts of wind and cause increased limit loads, so there is an urgent need Provide a control method capable of suppressing the overspeed of wind turbines, so as to improve the operational reliability of wind turbines under conditions such as extreme gusts

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