Control of Circulating Current for Direct-Parallel Connected PWM Inverters

Abstract:

It can not only make the system more flexibly, but also can make the maximum power higher by using the direct-parallel connected inverters. However, when grid-connected inverters operate in direct-parallel structure, it may lead to potential circulating current. So its important to inhibit circulating current. Its found that the circulating current can be suppressed by controlling the operation time of zero vectors during every PWM cycle of space vector pulse width modulation (SVPWM). Meanwhile, we can add a current-average loop to the system so as to make the circulating current smaller. Simulation results in MATLAB are presented to prove the effectiveness of this method in this paper.

• Periodical: Advanced Materials Research (Volumes 756-759)
• Pages: 612-617
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.756-759.612
• Online since: September 2013
• Authors: Chun Xue Wen, Kun Kun Fang
• Keywords: Circulating Current, Direct-Parallel Connected Inverter, Operation Time of Zero Vectors

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