Hybrid HVDC transmission swegrids-logo

SweGRIDS research area SMARTPOWER
SweGRIDS project code SP8
Project type PhD
Status completed
Researcher Panagiotis Bakas   (webpage)
University KTH (EPE)
Project period 2014-05-01 to 2019-11-20   
Project supervisor Lennart Harnefors   (webpage)
Industrial sponsors ABB


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Project abstract

HVDC transmission is an important technology that enables the bulk transfer of energy, renewable integration, as well as the interconnection of asynchronous grids. Thus far, HVDC applications have been dominated by the line-commutated converter (LCC) that is a reliable, efficient, and dc-fault tolerant technology. However, the LCC requires large amounts of reactive power and is sensitive to ac faults. These shortcomings are solved by the emerging voltage-source converter (VSC) that is a highly controllable and ac-fault tolerant technology. Nevertheless, the VSC cannot handle as much power as the LCC and is sensitive to dc faults. Therefore, this project aims to create new hybrid topologies that combine the advantages of the LCC and the VSC and are fault-tolerant.


Summary of work

2014-2015. Basic PSCAD models of the LCC have been developed and brief literature review on hybrid topologies was performed. Four interesting hybrid topologies have been identified and have been evaluated in detail. Part of this evaluation has been published in ECCE Asia 2016 and the comprehensive results have been submitted to IEEE Transactions of Power Electronics.

2014-2015. A more comprehensive literature review is currently performed and the most recent hybrid topologies are being evaluated. Based on the findings in the literature reviews, new hybrid topologies should be proposed and compared with the existing ones. Finally, the most promising hybrid topology for HVDC transmission will be identified and studied via simulations and a small-scale laboratory prototype.

2016. First evaluation of potential hybrid converters has been finalized. Parts of the evaluation results were published in a conference paper and the complete results were published in a journal paper. The journal paper was accepted in IEEE Transactions on Power Electronics and is available for early access.

2016. The planning of a flexible laboratory prototype that will be used among several PhD students has been established and the lab work is on-going.

2017. Research activities lead to the proposal of two hybrid converters that feature increased power-transfer capability compared to the state-of-the-art voltage-source converters.

2017. The first version of the flexible laboratory prototype is running and being tested.

2018. The simulation model of the selected hybrid converter model has been implemented and a single-phase prototype has been designed. The prototype is currently under construction.

2019. The single-phase prototype of the selected hybrid converter has been finalized and experimental results of interest have been obtained. The remaining papers (journal+conference) and the PhD thesis have been written and submitted. The PhD thesis was successfully defended on Wednesday the 20th of November 2019.


Event log

2016. Attended the 2016 8th International Power Electronics and Motion Control Conference - ECCE Asia (IPEMC 2016-ECCE Asia), 22-25 May 2016, Hefei, China.

2017. Attended the 19th European Conference on Power Electronics and Applications, EPE’17 ECCE Europe, 11-14 September 2017, Warsaw, Poland.

2018. Attended the 20th European Conference on Power Electronics and Applications EPE’18 ECCE Europe, 17-21 September 2018, Riga, Latvia.

2019. Attended the 21st European Conference on Power Electronics and Applications EPE’19 ECCE Europe, 2-6 September 2019, Genova, Italy.


Project reference-group

Staffan Norrga,  KTH
Hans-Peter Nee,  KTH
Alireza Nami,  ABB Corporate Research
Kalle Ilves,  ABB Corporate Research
Frans Dijkhuizen,  ABB Corporate Research


Publications by this researcher

See alternatively the researcher's full DiVA list of publications, with options for sorting.
Publications in journals and conferences usually will not show until a while after they are published.

Hybrid alternate-common-arm converter with high power capability : Potential and limitations
Panagiotis Bakas,   Kalle Ilves,   Yuhei Okazaki,   Lennart Harnefors,   Staffan Norrga,   Hans-Peter Nee.
2020,   IEEE transactions on power electronics, vol. 35(12)

Implications of Capacitor Voltage Imbalance on the Operation of the Semi-Full-Bridge Submodule
Stefanie Heinig,   Keijo Jacobs,   Kalle Ilves,   Luca Bessegato,   Panagiotis Bakas,   Staffan Norrga,   Hans-Peter Nee.
2019,   IEEE transactions on power electronics, vol. 34(10)

Hybrid Converters for HVDC Transmission
Panagiotis Bakas.
2019,   Thesis (PhD), KTH Royal Institute of Technology, TRITA-EECS-AVL 2019:62

Design considerations and comparison of hybrid line-commutated and cascaded full-bridge converters with reactive-power compensation and active filtering capabilities
Panagiotis Bakas,   Yuhei Okazaki,   Kalle Ilves,   Staffan Norrga,   Lennart Harnefors,   Hans-Peter Nee.
2019,   2019 21st European Conference on Power Electronics and Applications (EPE'19 ECCE Europe), 3-5 September 2019, Genova, Italy

Hybrid alternate-common-arm converter with director thyristors : Impact of commutation time on the active-power capability
Panagiotis Bakas,   Kalle Ilves,   Staffan Norrga,   Lennart Harnefors,   Hans-Peter Nee.
2019,   2019 21st European Conference on Power Electronics and Applications (EPE'19 ECCE Europe), Genova, Italy, Sep. 2-6, 2019

Hybrid Converter With Alternate Common Arm and Director Thyristors for High-Power Capability
Panagiotis Bakas,   K. Ilves,   Lennart Harnefors,   Staffan Norrga,   Hans-Peter Nee.
2018,   2018 20th European Conference on Power Electronics and Applications (EPE’18 ECCE Europe)

Design of a Modular Multilevel Converter Prototype for Research Purposes
Luca Bessegato,   Anant Narula,   Panagiotis Bakas,   Staffan Norrga.
2018,   EPE'18 ECCE Europe

A Review of Hybrid Topologies Combining Line-Commutated and Cascaded Full-Bridge Converters
Panagiotis Bakas,   Lennart Harnefors,   Staffan Norrga,   Alireza Nami,   Kalle Ilves,   Frans Dijkhuizen,   Hans-Peter Nee.
2017,   IEEE transactions on power electronics, vol. 32(10)

Hybrid Topologies for Series and Shunt Compensation of the Line-Commutated Converter
Panagiotis Bakas,   Lennart Harnefors,   Staffan Norrga,   A. Nami,   K. Ilves,   F. Dijkhuizen,   Hans-Peter Nee.
2016,   8th IEEE International Power Electronics and Motion Control Conference, IPEMC-ECCE Asia 2016, Hefei, China, 22 May 2016 through 26 May 2016

Publication list last updated from DiVA on 2024-08-22 22:59.


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