Active Circulating Current Reduction for Three-Phase Three-Level Modular Photovoltaic Grid-Connected System

Abstract:

According to the active circulating current existing in the three-phase three-level modular photovoltaic grid-connected system, an equivalent model of the active circulating current is built on the basis of the topology and control of the modular system, and the exciting source and the impedance are analyzed in detail. One kind of current-sharing loop is proposed. The error between the average reference current and the feedback current with PI controller is added to the output of the DC voltage loop. Thus the impedance of the active circulating current is enhanced within low frequency range and the active circulating current is reduced effectively. Lastly, A 10kW three-phase three-level modular photovoltaic grid-connected system is built, and experimental results demonstrate the correctness of the model analysis and reduction methods.

• Periodical: Applied Mechanics and Materials (Volume 339)
• Pages: 568-573
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.339.568
• Online since: July 2013
• Authors: Fu Sheng Wang, Xiao Fei Wang, Xing Zhang, Zhang Ping Shao, Ping Liu
• Keywords: Active Circulating Current, Grid Connected, Module Current-Sharing Loop, Three-Level

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