PhD defence by Jinkui He
12.01.2022 kl. 07.00 - 10.00
Jinkui He, AAU Energy, will defend the thesis "Reliability Enhancement of 1500-V DC-link Photovoltaic Power Converters"
Reliability Enhancement of 1500-V DC-link Photovoltaic Power Converters
Professor Francesco Iannuzzo
Assistant Professor Ariya Sangwongwanich
Associate Professor Yongheng Yang
Professor Huai Wang
Associate Professor Szymon Bęczkowski, Aalborg University, Denmark (Chairman)
Professor Martin Ordonez, University of British Columbia, Vancouver, Canada
Professor Marta Molinas, NTNU Trondheim, Norge
Photovoltaic (PV) systems are becoming one of the essential renewable energy sources and play a growing role in today's power grid. More PV systems are expected to be installed in the near future and will share a major part of the power production. In this transition, the cost of PV energy should be further reduced. One standard solution is to increase the maximum DC-link voltage of the PV system from the traditional 1000 V to 1500 V. The benefit of doing so is a considerable decrease in the installation cost, power losses (e.g., due to cabling), and thereby the cost of PV energy. However, the increased DC-link voltage also imposes a challenge to PV inverters, which are the key components to achieve efficient and reliable power conversions. The increased voltage stress at the DC-link has pushed the inverter design from the conventional two-level topology toward multilevel topology. Although a few commercial products are already available on the market, the converter reliability assessment for this particular application is of high interest to be investigated. Moreover, the control strategy should also be improved in order to maintain high reliability under the 1500-V operation. Therefore, the main motivation of this project is to investigate how the increased DC-link voltage affects the reliability performance of the PV power converters, and thus to develop viable design and control solutions to ensure an reliable energy conversion while fulfill the grid requirements.
THE DEFENCE will be IN ENGLISH - all are welcome.