Dr Jonathan Davidson
Department of Electronic and Electrical Engineering
Electrical Machines and Drives Research Group
I joined the department in 2006 and studied both my MEng and PhD here, graduating in 2010 and 2015 respectively.
After a brief time as a postdoctoral researcher, I was appointed as a lecturer in the Electrical Machines and Drives group in 2015. I was made Senior Lecturer in 2022.
In both my research and teaching, I address interdisciplinary problems and themes and work with other academics from departments across the faculty.
My main research focus is on power electronics and covers two distinct but overlapping topics: electrical power conversion, and impedance sensing and system modelling. My power conversion research covers primarily resonant converters using both traditional magnetic resonant tanks and piezoelectric transformers (Grant: FPeT £600k, 2017) and lately high frequency supplies for chemical species selective reactions (Grant: Targeted waveform plasma reactor £980k, 2019). Notable successes in the field include the development of a design criterion for efficient piezoelectric transformers and a thorough exploration of the geometry requirements for transformers.
I have applied impedance sensing and system modelling to several areas. In the converters scene, it has driven the evaluation of piezoelectric transformer design and it is an enabling technology for the chemical species selection. In addition, it is the primary enabler of work on sewage sensing (Grants: Hydro Intl £200k, 2019; NBIC £50k 2020) which focusses on early detection of sediment build-up, examining the chemistry during destructive testing of electrochemical cells and producing accurate dynamic thermal models of power electronics.
My teaching focus has been on electrical engineering for interdisciplinary engineers. I was originally appointed as the electrical engineering lead to design a new programme in general engineering; I continue to lecture students in their first and second years on electrical engineering and interdisciplinary design. In 2021, I was appointed Deputy Director of Aerospace Engineering where my focus is on the design and operation of the avionics curriculum.
My teaching uses a combination of traditional visualiser note-making, pre-prepared videos, role-play group work and laboratory projects to provide students with an experience of all that engineering has to offer. I also offer final year projects to general, aerospace and electrical engineering students.
- PhD (Electronic and Electrical Engineering), University of Sheffield, 2015
- MEng (Electronic Engineering), University of Sheffield 2010
- Research interests
- Power electronic converters and drives
- Piezoelectric transformer-based power supplies
- Electrical sensing of water systems
- Thermal modelling and temperature estimation
- Pseudorandom binary sequences for system identification
- Electrochemical battery modelling
- Fully-integrated Transformer with Asymmetric Primary and Secondary Leakage Inductances for a Bidirectional Resonant Converter. IEEE Transactions on Industry Applications, 1-11.
- Circuit Simulator Compatible Model for the Ring-Dot Piezoelectric Transformer. Journal of Microelectromechanical Systems, 32(1), 103-116.
- Inserted-Shunt Integrated Planar Transformer With Low Secondary Leakage Inductance for LLC Resonant Converters. IEEE Transactions on Industrial Electronics, 70(3), 2652-2661.
- Comparison of BSPT and PZT Piezoelectric Ceramic Transformers for High‐Temperature Power Supplies. Advanced Engineering Materials, 24(12), 2200513-2200513.
- A Monte Carlo simulator to investigate cell‐to‐cell deviation in a grid‐tied battery pack. IET Power Electronics, 15(13), 1264-1278.
- Fully-Integrated Solid Shunt Planar Transformer for LLC Resonant Converters. IEEE Open Journal of Power Electronics, 3, 26-35.
- Fully-Integrated Planar Transformer With a Segmental Shunt for LLC Resonant Converters. IEEE Transactions on Industrial Electronics, 69(9), 9145-9154.
- Evaluation of silicon MOSFETs and GaN HEMTs in soft‐switched and hard‐switched DC‐DC boost converters for domestic PV applications. IET Power Electronics, 14(5), 1032-1043.
- Single‐active switch high‐voltage gain DC–DC converter using a non‐coupled inductor. IET Power Electronics, 14(3), 492-502.
- Influence of Spurious Modes on the Efficiency of Piezoelectric Transformers: A Sensitivity Analysis. IEEE Transactions on Power Electronics, 36(1), 617-629.
- Advanced abuse modelling of Li-ion cells – A novel description of cell pressurisation and simmering reactions. Journal of Power Sources, 474, 228396-228396. View this article in WRRO
- Conductance-Based Interface Detection for Multi-Phase Pipe Flow. . Sensors (Basel, Switzerland), 20(20), E5854.
- Resonant Current Estimation and Phase-Locked Loop Feedback Design for Piezoelectric Transformer-Based Power Supplies. IEEE Transactions on Power Electronics, 35(10), 10466-10476.
- Equivalent circuit parameter extraction of low‐capacitance high‐damping PTs. Electronics Letters, 56(7), 347-350.
- PLL controller for achieving zero‐voltage switching (ZVS) in inductorless half‐bridge drive piezoelectric transformer resonant power supplies. The Journal of Engineering, 2019(17), 3639-3642.
- Quantitative power loss analysis and optimisation in N th‐order low‐voltage multilevel converters. IET Power Electronics, 12(7), 1652-1661.
- Pursuing safer batteries: Thermal abuse of LiFePO4 cells. Journal of Power Sources, 414, 557-568.
- Automated design tools for piezoelectric transformer-based power supplies. The Journal of Engineering, 2019(17), 4163-4166. View this article in WRRO
- Real-time temperature estimation in a multiple device power electronics system subject to dynamic cooling. IEEE Transactions on Power Electronics, 31(4), 2709-2719. View this article in WRRO
- Critical Design Criterion for Achieving Zero Voltage Switching in Inductorless Half-Bridge-Driven Piezoelectric-Transformer-Based Power Supplies. IEEE TRANSACTIONS ON POWER ELECTRONICS, 31(7), 5057-5066.
- Measurement and Characterization Technique for Real-Time Die Temperature Prediction of MOSFET-Based Power Electronics. IEEE Transactions on Power Electronics, 31(6), 4378-4388. View this article in WRRO
- Real-Time Prediction of Power Electronic Device Temperatures Using PRBS-Generated Frequency-Domain Thermal Cross Coupling Characteristics. IEEE Transactions on Power Electronics, 30(6), 2950-2961. View this article in WRRO
- Improved Bandwidth and Noise Resilience in Thermal Impedance Spectroscopy by Mixing PRBS Signals. IEEE Transactions on Power Electronics, 29(9), 4817-4828.
- Required Cauer network order for modelling of thermal transfer impedance. Electronics Letters, 50(4), 260-262.
- Evaluation of UltraBattery™ performance in comparison with a battery-supercapacitor parallel network. Journal of Power Sources, 226, 191-201.
- Arbitrary waveform power controller for thermal measurements of semiconductor devices. Electronics Letters, 48, 400-402.
Conference proceedings papers
- Resonant current estimation and phase-locked loop control system for inductorless step-up single piezo element-based (SUPRC) DC-DC converter. IECON 2022 – 48th Annual Conference of the IEEE Industrial Electronics Society, 17 October 2022 - 20 October 2022. View this article in WRRO
- Critical design criterion for inductorless H-bridge driven piezoelectric-transformer-based power supplies. IECON 2022 – 48th Annual Conference of the IEEE Industrial Electronics Society, 17 October 2022 - 20 October 2022. View this article in WRRO
- Analysis of Test Methods for Measurement of Leakage and Magnetising Inductances in Integrated Transformers. 24th European Conference on Power Electronics and Applications, EPE 2022 ECCE Europe
- Parameterisation Methods For Piezoelecric Transformer Equivalent Circuit Models. Power Electronics, Machines and Drives (PEMD) 2022
- Resonant current estimation and voltage regulation for piezoelectric transformer-based power supply. 11th International Conference on Power Electronics, Machines and Drives (PEMD 2022) (pp 357-361)
- Performance Of Pzt-based Piezoelectric Transformers For Use In High-temperature Converters. Power Electronics, Machines and Drives (PEMD) 2022
- Cyclic-mode Modelling Of Class EF/2 inverters Featuring a Piezoelectric Resonator As The Auxiliary Network. Power Electronics, Machines and Drives (PEMD) 2022
- Fully-integrated Transformer With Asymmetric Leakage Inductances for a Bidirectional Resonant Converter. Power Electronics, Machines and Drives (PEMD) 2022
- RadPTDesigner: A program for designing radial mode piezoelectric transformers for inductorless inverters. 2021 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE Europe), 6 September 2021 - 10 September 2021.
- Design and Analysis of a Fully-integrated Planar Transformer for LCLC Resonant Converters. 2021 23rd European Conference on Power Electronics and Applications (EPE'21 ECCE Europe), 6 September 2021 - 10 September 2021.
- Comparative evaluation of Si mosfet-based soft-switched DC-DC converters and gan HEMT-based hard-switched DC-DC converters. IET Conference Publications, Vol. 2020(CP766) (pp 670-675)
- Output voltage regulation for piezoelectric transformer-based resonant power supplies using phase-locked loop. IET Conference Publications, Vol. 2020(CP766) (pp 455-460)
- A large-scale battery energy storage system simulation tool for studying cell variation. IET Conference Publications, Vol. 2020(CP766) (pp 261-265)
- Analysis, Design and Modelling of Two Fully- Integrated Transformers with Segmental Magnetic Shunt for LLC Resonant Converters. IECON 2020 The 46th Annual Conference of the IEEE Industrial Electronics Society, 18 October 2020 - 21 October 2020.
- Computational modelling of thermal runaway propagation potential in lithium iron phosphate battery packs. Energy Reports, Vol. 6 (pp 189-197)
- Online electrolytic capacitor prognosis system for PWM drives. 2019 21st European Conference on Power Electronics and Applications (EPE '19 ECCE Europe), 3 September 2019 - 5 September 2019. View this article in WRRO
- Equivalent Circuit Parameter Extraction Methods for Piezoelectric Transformers. 2019 21st European Conference on Power Electronics and Applications (EPE '19 ECCE Europe), 3 September 2019 - 5 September 2019. View this article in WRRO
- Assessment of thermal runaway in commercial lithium iron phosphate cells due to overheating in an oven test. Energy Procedia, Vol. 151 (pp 74-78)
- View this article in WRRO Observations on Changes to Electrolytic Capacitor Electrical Properties Caused by Gamma Irradiation. IWIS 2016, 26 September 2016 - 28 September 2016.
- Thermal Analysis Using 2-Dimensional Impedance Spectroscopy and Pseudorandom Binary Sequences. IWIS 2016
- View this article in WRRO Measurement of Electrical Parameters of Electrolytic Capacitors Using Real-World Drive Waveforms for State-of-Health Determination. IWIS 2016, 26 September 2016 - 28 September 2016.
- View this article in WRRO Electrolytic capacitor age estimation using PRBS-based Techniques. PCIM Europe 2016; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management (pp 1095-1102)
- Minimum charge-recovery time control with parallel connected buck converters. 8th IET International Conference on Power Electronics, Machines and Drives (PEMD 2016) View this article in WRRO
- Observation of electrolytic capacitor ageing behaviour for the purpose of prognostics. IECON 2016 - 42nd Annual Conference of the IEEE Industrial Electronics Society, 23 October 2016 - 26 October 2016. View this article in WRRO
- Real-time temperature monitoring and control for power electronic systems under variable active cooling by characterisation of device thermal transfer impedance. 7th IET International Conference on Power Electronics, Machines and Drives (PEMD 2014)
- Prediction of device temperatures in an electric vehicle battery charger system by analysis of device thermal cross-coupling. 2013 15th European Conference on Power Electronics and Applications (EPE), 2 September 2013 - 6 September 2013.
- Mixed PRBS technique for thermal impedance spectroscopy of power electronic systems. PCIM Europe Conference Proceedings (pp 1047-1054)
- Erratum for ‘Arbitrary waveform power controller for thermal measurements of semiconductor devices’. Electronics Letters, Vol. 48(11) (pp 665)
- Effect of spurious resonant modes on the operation of radial mode piezoelectric transformers. PCIM Europe 2018; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management (pp 1740-1747). Nuremberg, Germany, 5 June 2018 - 7 June 2018.
- Professional activities and memberships
- Deputy Director, Aerospace Engineering
- Electrical engineering theme liaison, General Engineering