DC power collection system for PV station based on impedance‐source multi‐module DC–DC step‐up converter. Issue 13 (19th January 2018)

• Record Type: Journal Article
• Authors: Li, Xiuyi; Zhu, Miao; He, Guoqing; Cai, Xu
• Is Part Of: Journal of engineering. Volume 2017:Issue 13(2017)
• Page Start: 1734
• Page End: 1739
• Publication Date: 2018-01-19
• Subjects: photovoltaic power systems -- maximum power point trackers -- power grids -- power generation control; DC power collection system -- impedance‐source multimodule DC‐DC step‐up converter -- photovoltaic station -- impedance network concepts -- large‐scale PV station -- integrated function -- multimaximum power point tracking control -- high‐gain DC voltage step‐up conversion -- low‐voltage DC bus -- distributed MPPT devices -- internal fault isolation -- unitary dynamic control -- station level -- impedance network -- voltage gain -- bridge arms -- operational adaptability -- system architecture -- working principle -- modulation strategy -- balanced power inputs -- mismatched power inputs -- application value -- power collection grid; Engineering -- Periodicals; Engineering; Electronic journals; Periodicals; 620.005
• DOI: 10.1049/joe.2017.0629
• Languages: English
• ISSNs: 2051-3305

Abstract

Abstract : In this study, a novel structure of DC power collection system for photovoltaic (PV) station with consideration of impedance network concepts has been proposed to cope with technical challenges in large‐scale DC PV Station. An impedance‐source multi‐module cascaded DC–DC step‐up converter serves as a key device for the proposed collection grid, which has an integrated function of multi‐maximum power point tracking (MPPT) control and high‐gain DC voltage step‐up conversion. The low‐voltage DC bus and distributed MPPT devices can be omitted to make the system simple and reliable. The system structure is beneficial to realise internal fault isolation and unitary dynamic control at station level. The introduction of impedance network makes it possible to adjust the voltage gain flexibly as well as resist shoot‐through of bridge arms, which can improve the operational adaptability against input power mismatch and reliability of the DC power collection grid for PV station. A detailed introduction to system architecture, key DC step‐up converter, working principle and control/modulation strategy has been given in this study. All theoretical results have been validated by system simulation under balanced and mismatched power inputs. The proposed DC power collection grid for PV station has a potential application value in the future construction of large‐scale DC PV stations.