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Isavella Koukoula: Enhancing the power electronic converters' capabilities through optimal modulation

Tampereen yliopisto
SijaintiKorkeakoulunkatu 1, Tampere
Hervannan kampus, Tietotalo, sali TB109 ja etäyhteys
Ajankohta31.10.2025 12.00–16.00
Kielienglanti
PääsymaksuMaksuton tapahtuma
Isavella Koukoula.
Kuva: Rajesh Singapati
The global goals of sustainability and energy efficiency lead to a surge in demand for the electrification of industrial applications. Power electronic converters are used to control the speed of high-power electric motors in energy-intensive industries, such as oil and gas. The utilisation of power electronics for driving electrical machines can result in increased energy savings, but at the same time poses challenges regarding the power quality produced. In her doctoral dissertation, M.Sc. Isavella Koukoula has developed optimal modulation strategies to enhance the performance of industrial drives and extend the equipment lifespan.

Conventional modulation methods aim to produce low harmonic distortions for load-friendly operation, but the converter is usually neglected. At the same time, achieving converter-friendly operation typically has an adverse effect on the load machine. Thus, advanced modulation methods are needed to achieve a better trade-off between converter- and load-friendly operation.

To improve the trade-off, M.Sc. Isavella Koukoula utilised optimised pulse patterns (OPPs) as they can achieve output currents of the highest quality possible, even at very low switching frequencies. 

Since OPPs are computed by solving an optimization problem, additional requirements can be added as secondary objectives. 

“This way, OPPs were developed to include additional features that extend the lifetime of electrical machines, increase the converter’s maximum output power and efficiency, and improve overall system reliability,” Koukoula explains.

These advancements holistically enhance the performance of the drive system, contributing to more sustainable and energy-efficient operation and supporting global decarbonization and electrification efforts.

Public defence on Friday 31 October

The doctoral dissertation of M.Sc. Isavella Koukoula in the field of electrical engineering titled Advanced Optimized Pulse Patterns for Medium-Voltage Drives will be publicly examined at the Faculty of Information Technology and Communication Sciences at Tampere University at 12:00 on Friday 31.10.2025 at Hervanta campus, Tietotalo, at the auditorium TB109 (Korkeakoulunkatu 1, Tampere). The Opponent will be Associate Professor Drazen Dujic from École Polytechnique Fédérale de Lausanne (EPFL), Switzerland. The Custos will be Associate Professor Petros Karamanakos from The Faculty of Information Technology and Communication Sciences, Tampere University. 


The doctoral dissertation is available online.
The public defence can be followed via remote connection.