Thermal-Conditioned Braking Torque Control for Modern Wind Turbines

Abstract:

A new soft-braking strategy for modern Wind Turbines (WTs) is proposed. The braking torque is directly controlled by regulating the caliper’s hydraulic pressure via a controllable pressure valve, subject to some thermal constraints about mechanic braking units. The proposed control strategy consists of a pressure controller, a braking controller and an optimization algorithm for generating a braking torque reference. The modeling issues and some of these design/developments based on a lab-sized setup are discussed. Comparing with the existing WT braking solutions, either through an on/off control, or through some soft-braking mechanism which mainly employs a kind of generator-shaft speed control, the proposed approach can control the brake-induced mechanic stress to the transmission system in a more effective manner, and meanwhile, the thermal stress to the braking units is also explicitly cooperated into this design.

• Periodical: Applied Mechanics and Materials (Volume 197)
• Pages: 391-395
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.197.391
• Online since: September 2012
• Authors: Zhen Yu Yang, Frank Jepsen, Anders Søborg
• Keywords: Brake System, Disturbance Rejection, Thermal Constraint, Torque Control, Wind Turbine (WT)

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DOI: 10.1109/energycon.2010.5771739

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