- Electronics and Electrical Engineering
Since 2012, I have held a Personal Chair in Electrical Generation Systems at the University of Edinburgh, having been appointed as a lecturer in 2004. In 2023 I was awarded a Royal Academy of Engineering Chair in Emerging Technologies to investigate new high power density high temperature superconducting machines for net-zero energy and transport applications. From 2014 to 2018, I led a group of 26 academics as Head of the Institute for Energy Systems, and I am now co-leading Energy@Edinburgh, a cross university community of 200+ academics and researchers focussing on energy systems. I have supported 25 PhD students to successful graduation as principal supervisor, and supervised 18 PDRAs. My PhDs and PDRAs continue to work in electrical power engineering in both academia and industry.
My research focusses on electrical generators for renewable energy converters, and the development of hybrid energy systems integrating renewables and energy storage for on and off-grid use. Since 1997 I have been awarded £13m in grant funding, 75% as PI, from various sources: Royal Academy of Engineering, EPSRC, Innovate UK, The Carbon Trust, Scottish Enterprise, Wave Energy Scotland, Scottish Government, EU FP6, FP7, H2020 and ERDF, as well as direct industrial funding. As well as being part of consortia in EU grants working with eg. TU Delft, NTNU, Cork University, RWTH Aachen, Tecnalia, Fraunhofer Wind, I have also led consortia – eg. EPSRC EDRIVE (£1m)– 2 universities and 4 industrial partners; Wave Energy Scotland Project Neptune (£2.5m) – 2 universities and 7 industrial partners. Between 2010 and 2016 I led a Scottish Knowledge Exchange network, RENEW-NET, with 5 academic partners securing £1m of funding from Scottish Enterprise, Scottish Gov and ERDF, providing technical support in electrical machines and power electronics to over 100 SMEs, with 30 receiving detailed support securing jobs, new contracts and further grant funding based on our support.
I work very closely with industry, and in some cases my team has designed and built C-GEN generators for use in pre-commercial devices: eg. Mocean Energy – 10kW generator installed in their Blue-X wave device tested at sea in 2021/22; Swift Energy – 16kW generator for vertical axis wind turbine; Ladco – 6 kW generator for wind turbine tested at Arbroath; Hydrokinetic Power Generation – 25 kW generator for a tidal device to be tested in Bordeaux in 2023
My research has been widely published in top ranked journals such as IEEE, IET, IMechE and IoP. To date I have 258 journal and conference publications, and my h-index is 38 with 6294 citations, 2887 since 2017 (Google Scholar). As well as papers I co-edited the book “Electrical Drives for Direct Drive Renewable Energy Systems” (Woodhead Publishing with Prof Henk Polinder at TU Delft, and have been awarded 3 patents. Most of my articles are in top ranked journals published by IEEE, IMechE, IET and IoP. In 2006 I was awarded the Donald Julius Groen Prize by the IMechE with my former PhD student Dr. Nick Baker, now a Reader at Newcastle University. My PhD student’s work was recognised with best conference paper prizes at the IEEE IEMDC Conference in 2010. In 2017 I was co-author on a paper awarded the Thomas L Fagan Jr RAMS award for the best paper at the Reliability & Maintainability Symposium held in Florida. I was part of team of 7 partners in an EU FP7 project led by NaREC (now the Offshore Renewable Energy Catapult) entitled SNAPPER involving the design and system modelling of a novel linear generator for wave energy won the Engineer Magazine Innovation Award Marine Category in 2012, and was a finalist in the IET Innovation Awards in 2012.
In 2009 I spun out NGenTec Ltd to commercialise the C-GEN technology for offshore wind, originally funded by Scottish Enterprise with £0.5m. NGenTec raised £7m from private and public sources leading to employment of 20 staff. In 2013 the university re-purchased the IP to enable me to develop C-GEN for a wider range of renewable energy applications. Since then we have sold pre-commercial demonstrators to Mocean Energy, Swift Energy, HydroKinetic Power Generation, and are undertaking design studies for other companies in, USA, Australia, Ireland, Sweden and Norway. More details on the C-GEN technology can be found at www.cgen.eng.ed.ac.uk.
- BSc(Eng) 1988 Imperial College, London
- PhD 1991 Electrical Engineering, University of Cambridge
Professional Qualifications and Memberships:
- CEng Chartered Engineer
- MIET Member of the Institute of Engineering & Technology
Design of Novel Electrical Machines
The design of novel generator topologies for direct drive wave energy, wind energy and tidal current energy converters is my main area of research.
There are both electrical and mechanical challenges to overcome. Low speed machines will be physically larger and heavier than conventional high speed generators. Novel machine topologies using permanent magnets (PM) have been developed, which exhibit high power density, such as the transverse flux machine and the vernier hybrid machine. I have done work with both of these machine topologies. However, these machines suffer very large magnetic attraction forces requiring a significant mechanical structure to maintain a physical airgap. Air-cored machines eliminate the unwanted magnetic attraction force leading, but exhibit a much lower force density. However, the elimination of the attraction force has the potential to lead to a lighter mechanical structure. An air-cored tubular permanent magnet machine has been designed and currently a novel air-cored machine which makes more effective use of the magnetic material in the machine compared to the tubular machine.
The influence of the electrical design on the mechanical design and vice versa forms the main thrust of my research into low speed electrical machines. In order to generate the optimum machine design such an integrated approach must be adopted.
Further details of current and completed research projects may be found at www.see.ed.ac.uk/~mmueller.
- Direct Drive Wave, Wind & Tidal Energy Systems
- Design and modelling of electrical machines
- High Temperature Superconducting Machines
- Electrical machines for renewable energy applications
- Low speed electrical generators for wave, wind and tidal energy converters
- Permanent magnet and switched reluctance machines
- Grant holder: Royal Academy of Engineering, Wave Energy Scotland, EPSRC, EU, NaREC, Industry, Scottish Enterprise, The Carbon Trust, The Energy Technology Partnership
- IET activities: Technical Adviser to Power Conversion and Applications Network, Committee member of the IET Conference on Power Electronics,Machines and Drives (PEMD)