Simplified Carrier-based PWM for Three-Level Transformer-Less Grid-connected Photovoltaic Inverters
Received: 13 July 2024 | Revised: 5 August 2024 | Accepted: 11 August 2024 | Online: 15 August 2024
Corresponding author: Arsalan Ansari
Abstract
This article proposes a simple and efficient carrier-based Pulse Width Modulation (PWM) technique for three-level transformer-less grid-connected Photovoltaic (PV) inverters. The three-level inverter is prone to an inherent issue of unbalanced DC-link voltages, which, when used in conjunction with transformer-less grid-connected PV systems, gives rise to leakage currents. A simplified carrier-based PWM is proposed to carry out the DC-link voltage balancing and suppress the leakage current -Common Mode CM current CM- in transformer-less grid-connected inverters. The implementation of the proposed strategy is straightforward and does not require complex calculations, in contrast to space vector-based PWM techniques or multi-carrier modulation techniques. The operation of the PWM strategy is demonstrated through simulations and validated through experimental results.
Keywords:
carrier-based PWM, grid-connected inverters, photovoltaicDownloads
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Copyright (c) 2024 Arsalan Ansari, Muhammad Dawood Idrees, Atif Jamil, Abdul Sami, Ramesh Kumar
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