Volltext-Downloads (blau) und Frontdoor-Views (grau)

Design of a Medium Voltage Generator with DC-Cascade for High Power Wind Energy Conversion Systems

  • This paper shows a new concept to generate medium voltage (MV) in wind power application to avoid an additional transformer. Therefore, the generator must be redesigned with additional constraints and a new topology for the power rectifier system by using multiple low voltage (LV) power rectifiers connected in series and parallel to increase the DC output voltage. The combination of parallel and series connection of rectifiers is further introduced as DC-cascade. With the resulting DC-cascade, medium output voltage is achieved with low voltage rectifiers and without a bulky transformer. This approach to form a DC-cascade reduces the effort required to achieve medium DC voltage with a simple rectifier system. In this context, a suitable DC-cascade control was presented and verified with a laboratory test setup. A gearless synchronous generator, which is highly segmented so that each segment can be connected to its own power rectifier, is investigated. Due to the mixed AC and DC voltage given by the DC-cascade structure, it becomes more demanding to the design of the generator insulation, which influences the copper fill factor and the design of the cooling system. A design strategy for the overall generator design is carried out considering the new boundary conditions.

Download full text files

Export metadata

Additional Services

Search Google Scholar Check availability


Show usage statistics
Document Type:Article
Author:Jonas Steffen, Sebastian Lengsfeld, Marco Jung, Bernd Ponick, Mercedes Herranz Gracia, Aristide Spagnolo, Markus Klöpzig, Klaus Schleicher, Klaus Schäfer
Parent Title (English):energies
Article Number:3106
Place of publication:Basel
Publishing Institution:Hochschule Bonn-Rhein-Sieg
Date of first publication:2021/05/26
Copyright:© 2021 by the authors. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license.
Funding Information:The authors would like to thank the German Federal Ministry for Economic Affairs and Energy as well as the Project Coordinator Jülich for funding the research project Magnetring III (support code 0324276A) leading to this article.
Keyword:DC-cascade; medium voltage insulation; permanent magnet synchronous generator (PMSG); power rectifier; wind energy conversion systems (WECS)
Departments, institutes and facilities:Fachbereich Ingenieurwissenschaften und Kommunikation
Institut für Technik, Ressourcenschonung und Energieeffizienz (TREE)
Dewey Decimal Classification (DDC):6 Technik, Medizin, angewandte Wissenschaften / 62 Ingenieurwissenschaften / 621.3 Elektrotechnik, Elektronik
Entry in this database:2021/06/12
Licence (German):License LogoCreative Commons - CC BY - Namensnennung 4.0 International