Article
Engineering, Electrical & Electronic
Ewan M. Farr, Ralph Feldman, Jon C. Clare, Omar F. Jasim
Summary: This article introduces ac fault ride-through strategies for the extended-overlap operating mode of the alternate arm converter, which are experimentally validated. The AAC offers benefits such as requiring fewer submodules with smaller capacitance compared to the half-bridge modular multilevel converter, and providing dc fault ride-through capability.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Zain Hassan, Alan J. Watson, Francesco Tardelli, Jon Clare
Summary: The modular multilevel converter (MMC) has become the industry standard for high voltage direct current (HVDC) applications due to its scalability, modularity, high efficiency, and better output quality. A switched mid-point modular multilevel converter (SMPC) is introduced in this paper as an alternative topology to reduce energy storage while maintaining the benefits of the MMC. The SMPC achieves significant energy storage reduction (around 50%) compared to the MMC, and the DC-side does not require additional filtering for distortion. However, it requires more switches and slightly lower efficiency.
IEEE TRANSACTIONS ON POWER DELIVERY
(2023)
Article
Automation & Control Systems
Sandeep Kaler, Amirnaser Yazdani
Summary: This article introduces a dynamic model and current-mode control for a DC-DC modular multilevel converter, aiming to expand the converter to a three-leg configuration in order to reduce filtering requirements. The complete model of the converter and systematic approach for power throughput control are developed and verified through simulations and experiments. Expanding from a single-leg to three-leg configuration effectively alleviates the filtering requirements on both high-voltage and low-voltage sides.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2021)
Article
Computer Science, Information Systems
Mohamed Ashraf, Yousef Nazih, Fahad Alsokhiry, Khaled H. Ahmed, Ayman S. Abdel-Khalik, Yusuf Al-Turki
Summary: This paper introduces a new modular multilevel converter (MMC) based front-to-front DC-DC converter to interconnect two different types of HVDC networks, providing uninterrupted bi-directional power flow, DC fault blocking capability, and low number of semiconductors. The paper also proposes and compares two active power control methodologies, as well as providing losses analysis and comparison between the two control techniques. Control-Hardware-in-the-Loop (CHiL) test validation is employed to confirm the validity of the proposed system under various scenarios.
Article
Energy & Fuels
Harith R. Wickramasinghe, Pingyang Sun, Georgios Konstantinou
Summary: This study demonstrates the interoperability of an emerging alternate arm converter (AAC) with the state-of-the-art modular multilevel converter (MMC) in high-voltage direct current (HVDC) systems based on a hybrid VSC-HVDC system. Through detailed analysis of an 800 MVA hybrid voltage source converter (VSC)-HVDC system, the study showcases the interoperability performance of the AAC under different operating scenarios and verifies its associated control functions.
Article
Engineering, Electrical & Electronic
Dimitrios Vozikis, Grain P. Adam, Pierre Rault, Olivier Despouys, Derrick Holliday
Summary: This article discusses the operating principles, performance, and variant design of the enhanced modular multilevel converter (EMMC). Through comprehensive simulation studies, it has been confirmed that EMMC is reliable in normal operation, fault tolerance, and specific functionalities.
IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS
(2021)
Article
Automation & Control Systems
Abraham M. Alcaide, Pablo Poblete, Sergio Vazquez, Ricardo P. Aguilera, Jose I. Leon, Samir Kouro, Leopoldo G. Franquelo
Summary: This article proposes a feed-forward compensation technique to address the challenges of short sampling time and unbalanced operational conditions in the operation of multilevel cascaded H-bridge (CHB) converters. Experimental results demonstrate the superior performance of the proposed strategy.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Fujin Deng, Jifeng Zhao, Chengkai Liu, Zheng Wang, Xu Cai, Frede Blaabjerg
Summary: This article proposes a variable frequency control strategy for balancing the temperature distribution among three phases of an MMC in the presence of unbalanced grid voltages. The proposed control effectively improves the reliability of the MMC.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Sumeet Singh Thakur, Milijana Odavic, Ahmed Allu, Z. Q. Zhu, Kais Atallah
Summary: This article presents a new closed-form analytical solution for analyzing the operation of a full-bridge modular multilevel converter in boost mode. The effects of modulation index, number of submodules, and upper/lower arm carrier phase shift angle on the output voltage harmonics are investigated.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Automation & Control Systems
Christopher D. Townsend, Graham Clifford Goodwin, Georgios Konstantinou, Nikola Petranovic, Galina Mirzaeva, Ghias Farivar, Josep Pou
Summary: The optimization approach developed in this article identifies harmonics that simultaneously achieve capacitor energy optimization and reduced overrating of converter currents, eliminating the possibility of convergence to local minima. Experimental verification of this approach is performed on a low-voltage three-phase modular multilevel converter.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2021)
Article
Automation & Control Systems
Aleksandr Viatkin, Mattia Ricco, Riccardo Mandrioli, Tamas Kerekes, Remus Teodorescu, Gabriele Grandi
Summary: A new Modular Multilevel Converter with Interleaved half-bridge Sub-Modules (ISM-MMC) is proposed in this article, which exhibits higher modularity and scalability for ultrafast chargers. A hybrid modulation scheme is implemented to exploit the advantages of the interleaving scheme. Comparative study verifies the effectiveness of the proposed topology.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Zhengxuan Li, Qiang Song, Shukai Xu, Biao Zhao, Zhanqing Yu, Rong Zeng
Summary: An approximate analysis method is proposed for the energy storage requirement in MMC with variable dc voltages. The optimal circulating current and practical curve-fitting approach are utilized to achieve low-energy storage requirements. The simulation and experimental results validate the analysis.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Mustafa Kaya, Alessandro Costabeber, Alan Watson, Francesco Tardelli, Jon Clare
Summary: This article introduces a push-pull series connected (PPSC) ac-dc converter for high-voltage direct current applications. The proposed topology requires fewer submodules compared to a standard modular multilevel converter (MMC) for the same dc voltage. Each converter phase unit is connected via a center-tapped single-phase transformer, providing galvanic isolation. The required arm inductance can be merged into the transformer leakage inductance. The design, operation, and comparison with MMC are discussed in detail.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Automation & Control Systems
Abraham Marquez, Jose Leon, Ramon Portillo, Jiapeng Yin, Wensheng Luo, Sergio Vazquez, Samir Kouro, Leopoldo G. Franquelo
Summary: The article presents a variable-angle phase-shifted pulsewidth modulation (PS-PWM) technique for CHB converters, achieving superior harmonic performance under unbalanced conditions.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Heya Yang, Shiyuan Fan, Yufei Dong, Huan Yang, Wuhua Li, Xiangning He
Summary: This article introduces an arm phase-shift conducting modulation strategy to improve the efficiency and reduce the cost of alternate arm multilevel converters. By introducing a phase-shift angle and using the half-bridge structure as the submodule topology, the energy stored in submodule capacitors can be effectively balanced and circuit complexity reduced. Simulation and experimental results validate the effectiveness of this modulation strategy.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)