Lu, Q., Bowyer, R. and Jones, B.L. (2015) Analysis and design of Coleman transform-based individual pitch controllers for wind-turbine load reduction. Wind Energy, 18 (8). 1451 - 1468. ISSN 1095-4244
Abstract
As the size of wind turbines increases, the effects of dynamic loading on the turbine structures become increasingly significant. There is therefore a growing demand for turbine control systems to alleviate these unsteady structural loads in addition to maintaining basic requirements such as power and speed regulation. This has motivated the development of blade individual pitch control (IPC) methodologies, many of which employ the Coleman transformation to simplify the controller design process. However, and as is shown in this paper, the Coleman transformation significantly alters the rotational system dynamics when these are referred to the non-rotating frame of reference, introducing tilt-yaw coupling in the process. Unless this transformation is explicitly included in the model employed for IPC design, then the resulting controllers can yield poor performance. Therefore, in this paper, we show how to model the Coleman transformation in a form that is amenable to IPC analysis and synthesis. This enables us to explain why traditional design parameters of gain and phase margin are poor indicators of robust stability and hence motivate the need for a multivariable design approach. The robust multivariable IPC approach advocated in this paper is based upon H∞ loop shaping and has numerous desirable properties, including reliable stability margins, improved tilt-yaw decoupling and simultaneous rejection of disturbance loads over a range of frequencies. The design of a robust multivariable IPC is discussed, and simulation results are presented that demonstrate the efficacy of this controller, in terms of load reduction on both rotating and non-rotating turbine parts.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2014 John Wiley & Sons, Ltd. This is an author produced version of a paper subsequently published in Wind Energy. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
|
Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Automatic Control and Systems Engineering (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 05 Oct 2015 14:55 |
Last Modified: | 21 Mar 2018 14:05 |
Published Version: | http://dx.doi.org/10.1002/we.1769 |
Status: | Published |
Publisher: | Wiley |
Refereed: | Yes |
Identification Number: | 10.1002/we.1769 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:90499 |