A Cost-Effective Decentralized Control for AC-Stacked Photovoltaic Inverters

For an AC-stacked photovoltaic (PV) inverter system with N cascaded inverters, existing control methods require at least N communication links to acquire the grid synchronization signal. In this paper, a novel decentralized control is proposed. For N inverters, only one inverter nearest the point of...

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Bibliographic Details
Main Authors: Hua Han, Chao Luo, Xiaochao Hou, Mei Su, Wenbin Yuan, Zhangjie Liu, Josep M. Guerrero
Format: Article
Language:English
Published: MDPI AG 2018-08-01
Series:Energies
Subjects:
Online Access:http://www.mdpi.com/1996-1073/11/9/2262
Description
Summary:For an AC-stacked photovoltaic (PV) inverter system with N cascaded inverters, existing control methods require at least N communication links to acquire the grid synchronization signal. In this paper, a novel decentralized control is proposed. For N inverters, only one inverter nearest the point of common coupling (PCC) needs a communication link to acquire the grid voltage phase and all other N − 1 inverters use only local measured information to achieved fully decentralized local control. Specifically, one inverter with a communication link utilizes the grid voltage phase and adopts current control mode to achieve a required power factor (PF). All other inverters need only local information without communication links and adopt voltage control mode to achieve maximum power point tracking (MPPT) and self-synchronization with grid voltage. Compared with existing methods, the communication link and complexity is greatly reduced, thus improved reliability and reduced communication costs are achieved. The effectiveness of the proposed control is verified by simulation tests.
ISSN:1996-1073