David Hewitt

Dr. David Hewitt is a Research Fellow in Power Electronics at the University of Sheffield’s School of Electrical and Electronic Engineering, affiliated with the Electrical Machines and Drives Research Group. His work focuses on advancing power electronics, electric machines, and predictive maintenance through thermal and fault diagnostic methodologies.

His research spans:

• High-frequency phenomena in electric machines and power converters
• Insulation health monitoring under extreme conditions (e.g., high dv/dt, thermal aging)
• Thermal management strategies for power electronics
• Early fault detection (e.g., turn-to-turn faults, partial discharges)
• Predictive maintenance using accelerated life testing and finite element analysis

Notable contributions include:

• Developing thermal observers for power module temperature estimation
• Experimental evaluation of SiC converter effects on machine insulation
• Electrolytic capacitor aging analysis for prognostics
• Thermally conductive encapsulant materials for improved thermal performance

He has authored over 20 peer-reviewed articles and conference papers, with ongoing work in aerospace power systems and high-power converter integration.