Modular input‐parallel output‐series DC/DC converter control with fault detection and redundancy. Issue 6 (1st April 2016)

• Record Type: Journal Article
• Authors: Lian, Yiqing; Adam, Grain; Holliday, Derrick; Finney, Stephen
• Is Part Of: IET generation, transmission & distribution. Volume 10:Issue 6(2016)
• Page Start: 1361
• Page End: 1369
• Publication Date: 2016-04-01
• Subjects: DC‐DC power convertors -- fault diagnosis -- wind turbines -- voltage control -- distributed control -- wind power plants; modular input‐parallel output‐series DC/DC converter control -- fault detection -- fault redundancy -- offshore wind farms -- medium‐voltage AC collection networks -- wind‐turbine power electronics -- input‐parallel output‐series connection -- semiconductor voltage ratings -- fault‐tolerant operation -- small‐signal analysis -- controller design -- master‐slave control scheme -- distributed voltage sharing controllers -- active power sharing -- parameter mismatch; Electric power production -- Periodicals; Electric power transmission -- Periodicals; Electric power distribution -- Periodicals; 621.3105
• DOI: 10.1049/iet-gtd.2015.0789
• Languages: English
• ISSNs: 1751-8687

Abstract

Abstract : Large offshore wind farms require extensive sub‐sea cables within the collection network. Present solutions are based around medium‐voltage AC collection networks. Recent studies have highlighted the potential benefits of DC collection networks. However, achieving DC/DC conversion at the required voltage and power levels presents a significant challenge for wind‐turbine power electronics. This study proposes an alternative DC collection network based around a modular DC/DC converter with input‐parallel output‐series connection. This modular topology can overcome the limitations imposed by semiconductor voltage ratings and provides fault‐tolerant operation. Small‐signal analysis of the converter is presented to be used to facilitate controller design for the converter input and output stages. A new master–slave control scheme and distributed voltage sharing controllers are proposed that ensure power sharing under all operating conditions, including during failure of a master module. This control scheme achieves fault‐tolerant operation by allowing the status of master module to be reallocated to any healthy module. The proposed control scheme is validated using simulation and experimentation, considering active power sharing between modules with parameter mismatch.