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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Current-Source Modular Medium-Voltage Grid-Connected System with High-Frequency Isolation for Photovoltaic Applications
AU - Darwish, Ahmed
AU - Elgenedy, Mohamed
N1 - ©2018 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
PY - 2019/3/1
Y1 - 2019/3/1
N2 - Large-scale grid-connected photovoltaic energy generation systems are progressing remarkably benefiting from the latest developments in solid-state semiconductors technology. In such systems, the photovoltaic arrays can be connected directly to the medium-voltage grid without employing a bulky line-frequency transformer to step up the voltage. Nano-crystalline cores with a small size and a high permeability operating at medium or high frequency can be installed in the power conversion stage. Hence, the necessary isolation as well as voltage boosting features can be provided. However, only a few power converters allow this type of isolation. This paper proposes a new modular converter structure suitable for medium-voltage grid connected systems with high-frequency isolation. The output voltages of the series-connected modules are added in order to provide the necessary voltage boosting. Four different power converter topologies with small input capacitors can be used as submodules for the presented medium-voltage configuration having different advantages and drawbacks. These different topologies are analysed in terms of power losses, footprint and functionality. To validate the mathematical analysis and the computer simulations, a scaled-down 5 kVA three-phase, 1 kV prototype is built and tested with four modules for each phase.
AB - Large-scale grid-connected photovoltaic energy generation systems are progressing remarkably benefiting from the latest developments in solid-state semiconductors technology. In such systems, the photovoltaic arrays can be connected directly to the medium-voltage grid without employing a bulky line-frequency transformer to step up the voltage. Nano-crystalline cores with a small size and a high permeability operating at medium or high frequency can be installed in the power conversion stage. Hence, the necessary isolation as well as voltage boosting features can be provided. However, only a few power converters allow this type of isolation. This paper proposes a new modular converter structure suitable for medium-voltage grid connected systems with high-frequency isolation. The output voltages of the series-connected modules are added in order to provide the necessary voltage boosting. Four different power converter topologies with small input capacitors can be used as submodules for the presented medium-voltage configuration having different advantages and drawbacks. These different topologies are analysed in terms of power losses, footprint and functionality. To validate the mathematical analysis and the computer simulations, a scaled-down 5 kVA three-phase, 1 kV prototype is built and tested with four modules for each phase.
U2 - 10.1109/TEC.2018.2876969
DO - 10.1109/TEC.2018.2876969
M3 - Journal article
VL - 34
SP - 255
EP - 266
JO - IEEE Transactions on Energy Conversion
JF - IEEE Transactions on Energy Conversion
SN - 0885-8969
IS - 1
ER -