Ultracapacitor storage enabled global MPPT for photovoltaic central inverters

Muller, Nicolas; Renaudineau, Hugues; Kouro, Samir; Wheeler, Patrick

Abstract

In most large-scale grid-tied photovoltaic (PV) plants, central inverter configurations are used, mainly due to higher converter efficiency and lower cost per kW. However, compared to other configurations, its Maximum Power Point Tracking (MPPT) efficiency is the lowest since it is the less distributed configuration. Under non-uniform conditions, as mismatch caused by aging and/or partial shading, several local maxima may arise in the PV curve, hence requiring additional actions to maximize the output power of the PV plant. Moreover, tighter grid codes have appeared, requiring for PV systems to limit power fluctuations. This paper presents an alternative to perform Global MPPT (GMPPT) while complying with stiffer grid code limitations. The proposed alternative adds an Energy Storage System (ESS) at inverter level, consisting of an ultracapacitor (UC) bank connected to the DC-link of a PV central inverter through interleaved DC-DC power converters. The proposed configuration is preliminary validated through simulations and tested under extreme conditions. The performance of the system is analyzed and compared to other existing solutions.

• Conference Name: IEEE 26th International Symposium on Industrial Electronics
• Conference Location: Edinburgh, UK
• Start Date: Jun 19, 2017
• End Date: Jun 21, 2017
• Acceptance Date: Mar 13, 2017
• Online Publication Date: Aug 7, 2017
• Publication Date: 2017
• Deposit Date: May 11, 2017
• Publicly Available Date: Aug 7, 2017
• Electronic ISSN: 2163-5145
• Peer Reviewed: Peer Reviewed
• Pages: 1046-1051
• Series ISSN: 2163-5145
• Book Title: 2017 IEEE 26th International Symposium on Industrial Electronics (ISIE)
• ISBN: 978-1-5090-1413-2
• DOI: https://doi.org/10.1109/ISIE.2017.8001390
• Public URL: https://nottingham-repository.worktribe.com/output/876780
• Publisher URL: http://ieeexplore.ieee.org/document/8001390/
• Related Public URLs: http://isie2017.org/; http://isie2017.org/index.php?page=1.home
• Additional Information: ISSN 2163-5145 © 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.