About the Project
This project is one of a number in competition for a studentship from the Faculty of Engineering and Design at the University of Bath. If successful, this studentship is expected to commence 04 October 2027.
An alternative start date may be possible if agreed with your intended supervisors and the Doctoral College.
Project Background:
The transition towards low-carbon energy requires wind-energy technologies with increased efficiency, reliability and operational lifespan. Magnetic levitation offers potential for wind-energy systems by providing contactless rotor support, reducing friction, mechanical wear and maintenance requirements [1–4]. These characteristics make magnetic bearing technologies particularly relevant to the development of efficient and reliable wind-energy systems.
However, magnetic levitation introduces additional challenges associated with rotor dynamics. The low mechanical damping associated with contactless support can increase susceptibility to vibration, instability and external disturbances. In active magnetic bearing systems, controllers are employed to regulate the rotor position and maintain contact-free operation [1, 3, 4]. Variations in rotational speed and aerodynamic loading introduce further dynamic uncertainties, requiring control strategies capable of maintaining satisfactory performance over a range of operating conditions [3–6].
This project will investigate advanced control strategies for magnetically levitated wind turbines, with particular emphasis on robust control. Mathematical models describing the dynamic behaviour of the magnetic levitation system will be developed and used to design control strategies for rotor stabilisation, vibration attenuation and disturbance rejection under uncertain and variable operating conditions.
Particular attention will be given to the nonlinear electromagnetic forces associated with magnetic bearings. Suitable nonlinear system representations will be considered to account explicitly for these effects within the control design. Robust control methods for nonlinear systems, including Lur’e system formulations and LMI-based stability and control conditions, provide a framework for addressing nonlinearities and model uncertainty [7, 8].
The project provides an opportunity to combine renewable-energy applications with dynamic modelling and advanced control design. The outcomes will contribute to ongoing research on magnetically levitated wind turbines and provide a basis for the future implementation and experimental validation of advanced control strategies on prototype systems.
Candidate requirements:
Applicants from Mechanical Engineering, Electrical and Electronic Engineering, Mechatronics, Control Engineering or other relevant engineering disciplines are encouraged to apply. An interest in dynamic systems, control, magnetic levitation systems and renewable-energy applications is desirable. Experience with mathematical modelling, system simulation, MATLAB/Simulink, Python or related computational tools would be advantageous.
Applicants must have, or be about to obtain, a UK Honours degree 1st or 2.1, or international equivalent. A master’s level qualification would also be advantageous.
Non-UK applicants, who are not currently studying in the UK, must meet the programme’s English language requirement before the application deadline – no exceptions will be considered.
Enquiries and Applications
Informal enquiries are encouraged. Direct these to Dr Ariadne Justi Bertolin - adljb20@bath.ac.uk
Please follow the below instructions carefully.
You must make a formal application via the University of Bath’s online application form for a PhD in Mechanical Engineering
Please note that you can apply for a maximum of two PhD projects on this programme.
In the ‘Funding Your Studies’ section, you must select ‘University of Bath URSA’ from one of the drop-down menus.
In the ‘Your PhD project’ section, you must quote the project title in the PhD project title field, and you must quote the lead supervisor’s name in the field ‘Name of intended supervisor at University of Bath.’
If you are applying for two projects, you must quote the project title for your second choice project in the field ‘Project 2 Title’ and the lead supervisor’s name in ‘Name of intended supervisor for 2nd choice project at University of Bath.
You must ensure that you follow the above steps correctly. Failure to complete these steps will cause errors in the automated processing of your application and may mean that you are not considered for a particular project.
Equality, Diversity and Inclusion
We value a diverse research environment and strive to be an inclusive university, where difference is celebrated and respected. We encourage applications from under-represented groups.
If you have circumstances that you feel we should be aware of that have affected your educational attainment, then please feel free to tell us about it in your application form. The best way to do this is a short paragraph at the end of your personal statement.
The Disability Service ensures that individuals with disabilities are provided the support that they need. If you state if your application that you have a disability, the Disability Service will contact you as part of this process to discuss your needs.
Keywords
Robust control; magnetic bearings; wind turbines; magnetic levitation; nonlinear control; stability control; dynamic systems; renewable energy.
Funding Notes
Applicants will be considered for a studentship. The Faculty of Engineering and Design at the University of Bath has studentships available for Home and Overseas students. However, in line with UKRI policy, the number of studentships available to Overseas students are capped. Studentships cover tuition fees, provide a £1k per annum training support fee, and a maintenance stipend (£21,805 2026/27 rate). International students will be required to cover the cost of a Student visa and Immigration Health Surcharge from personal funds.
References
[1] Schweitzer, G. and Maslen, E. H. (2009). Magnetic Bearings: Theory, Design, and Application to Rotating Machinery. Berlin, Heidelberg: Springer. doi: 10.1007/978-3-642-00497-1.
[2] Kumbernuss, J., Jian, C., Wang, J., Yang, H. X. and Fu, W. N. (2012). A novel magnetic levitated bearing system for Vertical Axis Wind Turbines (VAWT). Applied Energy, 90(1), pp. 148–153. doi: 10.1016/j.apenergy.2011.04.008.
[3] Fekry, M., Mohamed, A. M., Fanni, M. and Yoshida, S. (2019). A comprehensive performance assessment of the integration of magnetic bearings with horizontal axis wind turbine. Mathematics and Computers in Simulation, 156, pp. 1–39. doi: 10.1016/j.matcom.2018.06.011.
[4] Wu, H., Xiao, L., Wang, B., Li, G. and Li, P. (2010). Digital platform design for magnetically suspended bearings equipped for wind turbine based on DSP28335+FPGA. Proceedings of the 2010 IEEE/ASME International Conference on Mechatronic and Embedded Systems and Applications, Qingdao, China, pp. 283–287. doi: 10.1109/MESA.2010.5552053.
[5] Wang, M., Cole, M. O. T. and Keogh, P. S. (2017). New LMI based gain-scheduling control for recovering contact-free operation of a magnetically levitated rotor. Mechanical Systems and Signal Processing, 96, pp. 104–124. doi: 10.1016/j.ymssp.2017.04.008.
[6] Lusty, C. and Keogh, P. S. (2018). Active vibration control of a flexible rotor by flexibly mounted internal-stator magnetic actuators. IEEE/ASME Transactions on Mechatronics, 23(6), pp. 2870–2880. doi: 10.1109/TMECH.2018.2869023.
[7] Bertolin, A. L. J., Oliveira, R. C. L. F., Valmorbida, G. and Peres, P. L. D. (2022). An LMI Approach for Stability Analysis and Output-Feedback Stabilization of Discrete-Time Lur’e Systems Using Zames-Falb Multipliers. IEEE Control Systems Letters, 6, pp. 710–715. doi: 10.1109/LCSYS.2021.3086427.
[8] Bertolin, A. L. J., Oliveira, R. C. L. F., Valmorbida, G. and Peres, P. L. D. (2022). Control design of uncertain discrete-time Lur’e systems with sector and slope bounded nonlinearities. International Journal of Robust and Nonlinear Control, 32(12), pp. 7001–7015. doi: 10.1002/rnc.6181.