Improved Braking Torque Capacity

Finite Elements in Analysis and Design 59 (2012) 66–75

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Improved braking torque generation capacity of an eddy current brake with time varying magnetic fields: A numerical study
Kerem Karakoc a,n, Edward J. Park a,b, Afzal Suleman a a b

Department of Mechanical Engineering, University of Victoria, PO Box 3055, Victoria, BC, Canada V8W 2Y2 Mechatronic Systems Engineering, School of Engineering Science, Simon Fraser University, 250-13450 102nd Avenue, Surrey, BC, Canada V3T 0A3

a r t i c l e i n f o
Article history: Received 23 September 2011 Received in revised form 7 May 2012 Accepted 12 May 2012 Available online 13 June 2012 Keywords: Brake-by-wire Eddy current brakes Time-varying magnetic field Finite element analysis Automotive applications

a b s t r a c t
Eddy current brakes (ECB) are electrically controlled and non-contact actuators used as assistive brakes in vehicles. ECBs exhibit insufficient generated braking torque at low speeds. In order to overcome this, the use of AC magnetic fields with fixed and variable frequencies in different waveforms is investigated at both low and high speeds. Finite element analysis validated by an existing analytical model is performed for DC and AC magnetic fields. In addition, the frequency of the applied field is optimized using genetic algorithms on a generic ECB configuration. Crown Copyright & 2012 Published by Elsevier B.V. All rights reserved.

1. Introduction In brake-by-wire, some of the pure mechanical components of the conventional hydraulic brakes (CHBs) are replaced by electromechanical components. Having such an electromechanical system will result in a number of advantages, e.g., faster braking response time, easy implementation of various control systems, reduced number of components and wiring, less maintenance due to elimination of friction, elimination of hazardous brake

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