A small-scale wind turbine blade unified pitch system and pitch change method

Abstract

A small-scale wind turbine blade uniform pitch change system and pitch change method, the unified pitch change system includes a ball screw drive system, a blade uniform pitch change system, a pitch control system and a stepping motor, the pitch control system has a built-in The quasi-steady-state aerodynamic calculation method and the linear matrix inequality (LMI / IL) control method based on input quantity limitation, the present invention is based on the linkage structure system of ball screw drive and connecting rod movement. The pitch control system issues instructions to drive the stepper motor to drive the transmission gear, thereby driving the linkage structure system to realize the unified pitch motion of the blades. The LMI / IL algorithm is based on the judgment of the critical flutter state, deals with the quasi-steady-state aeroelastic system under the quasi-steady-state aerodynamic excitation, calculates the "theoretical pitch law" that meets the flutter suppression requirements, and tracks and optimizes the pitch process, avoiding the critical flutter area, so that the actual pitching law of the blade can meet the requirements of stall flutter suppression.

Description

technical field [0001] The invention belongs to the technical field of stall flutter suppression of small wind turbine blades, and in particular relates to a small wind turbine blade uniform pitch changing system and a pitch changing method. Background technique [0002] In recent years, new energy technologies for wind power generation have been greatly developed, especially wind energy capture machinery. Small wind turbine blades may break and fail under the nonlinear aerodynamic force of stall. Most of the conventional pitch control methods in the prior art are realized by conventional mechanical transmission and hydraulic transmission. Mechanical transmission has defects such as heavy mechanical equipment, complicated installation, and unstable driving. When hydraulic transmission is used, there are transmission lags and complicated hydraulic pipelines. and other defects, in addition, the prior art adopts direct suppression means to solve the blade stall flutter, based ...

AI Technical Summary

Problems solved by technology

Most of the conventional pitch control methods in the prior art are realized by conventional mechanical transmission and hydraulic transmission. Mechanical transmission has defects such as heavy mechanical equipment, complicated installation, and unstable driving. When hydraulic transmission is used, there are transmission lags and complicated hydraulic pipelines. and other defects, in addition, the prior art adopts direct suppression means to solve the blade stall flutter, based on this, the present invention proposes a small-scale wind turbine blade unified pitch system and pitch change method, the ball screw drive described in this design System, blade unified pitch system, quasi-steady-state aerodynamic calculation method and linear matrix inequality (LMI / IL) control method based on input limit, based on the critical quasi-steady-state aerodynamic excitation state, to achieve aeroelastic stability control (referred to as Aeroelastic control) can just make the blades adjust in a critical state in real time before entering the stall flutter state, avoid the flutter area, and realize flutter suppression

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