Article
Engineering, Electrical & Electronic
Chengkai Liu, Fujin Deng, Jianzhong Zhang, Xu Cai, Zhe Chen, Frede Blaabjerg
Summary: A controllable submodule (SM) based on a normally-on silicon carbide (SiC) junction field-effect transistor is proposed to reduce the power loss on bleeding resistor and improve the efficiency of modular multilevel converters (MMCs).
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Lianqiang Wang, Li Zhang, Yongsheng Xiong, Rui Ma
Summary: MMC systems have been a focus of research in medium-voltage motor drive applications, but the excessive SM capacitor voltage ripple at low speeds or start-up presents a major technological challenge. This paper proposes a new control strategy based on MPC, which successfully suppresses the SM capacitor voltage ripple by establishing system mathematical models and a cost function, and designing a control system. Compared to existing strategies, the MPC approach avoids modulation processes, PI regulation processes, and high frequency injection control.
JOURNAL OF POWER ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Huijie Jiang, Fujin Deng, Zheng Wang, Zhixiang Zou, Binbin Li, Frede Blaabjerg
Summary: This article proposes a harmonic optimization strategy to improve the harmonic performance of modular multilevel converters under submodule capacitor voltage reduction control. By adjusting the phase-shift angle and capacitor voltage to their optimal values, the converter's harmonics can be improved.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Ziyu Xia, Kishalay Datta, Jason T. Stauth
Summary: This article presents a state-space analysis of hybrid topologies to predict and control system dynamics, addressing the voltage imbalance issue in hybrid and resonant switched-capacitor converters.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Chengkai Liu, Fujin Deng, Qingsong Wang, Yanbo Wang, Frede Blaabjerg, Zheng Wang
Summary: A double half-bridge submodule-based MMC design is proposed in this letter, requiring only half the number of sensors to estimate capacitor voltages compared to traditional half-bridge submodule-based MMC designs, which proves to be more cost-effective. Simulation and experimental results confirm the effectiveness of the proposed method.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Automation & Control Systems
Hao Tian, Mingzhe Wu, Yun Wei Li
Summary: In this article, a precharging method for floating capacitors in seven-level hybrid clamped converters is proposed. By using specific switching states and selection schemes, the inrush current and voltage stress can be controlled without relying on dedicated power supplies, achieving safe precharging.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2022)
Article
Computer Science, Information Systems
Zhiting Mei, Jingyang Fang, Stefan Goetz
Summary: This article discusses two problems faced by lattice converters and proposes corresponding solutions. Firstly, it optimizes the efficiency of a given lattice converter by controlling the on/off states of H-bridge submodules. Secondly, it introduces a method to determine the voltage at each node of the converter to meet output voltage and current requirements. The article provides control methods for different sizes of lattice converters using graph theory and validates them with simulation results. The methodologies and algorithms described in the article are important for further design and improvement of efficient and easy-to-control lattice converters.
Article
Engineering, Electrical & Electronic
Jiapeng Yin, Jose Leon, Marcelo A. Perez, Leopoldo G. Franquelo, Abraham Marquez, Sergio Vazquez
Summary: The article proposes a low-cost MPC technique for MMCs to address the issue of high calculation involved in FCS-MPC. The arm voltage references for each phase are determined analytically, simplifying the optimization problem-solving process. Experimental tests show that this method has a clear advantage in terms of calculation cost while achieving similar performance.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Automation & Control Systems
Chengkai Liu, Fujin Deng, Qiang Yu, Yanbo Wang, Frede Blaabjerg, Xu Cai
Summary: This article proposes a submodule (SM) capacitance monitoring strategy for the MMC, where the fundamental frequency components of the SM capacitor voltage and current are extracted to estimate the SM capacitance based on reference, simplifying implementation and calculation, avoiding control limitations and heavy communication burden, and increasing accuracy. Simulation and experimental studies confirm the effectiveness of the proposed strategy.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2021)
Article
Energy & Fuels
Gustavo Gontijo, Songda Wang, Tamas Kerekes, Remus Teodorescu
Summary: The modular multilevel converter is a standard solution for high-power high-voltage applications operating at fixed frequency, but faces issues with high submodule-capacitor voltage ripple in machine-drive applications. On the other hand, the modular multilevel series converter offers better performance at low frequencies with smaller capacitors.
Article
Computer Science, Information Systems
Salvador Alepuz, Sergio Busquets-Monge, Joan Nicolas-Apruzzese, Alber Filba-Martinez, Josep Bordonau, Xibo Yuan, Samir Kouro
Summary: This paper provides a summary of neutral-point-clamped multilevel converters, focusing on the issue of capacitor voltage balance. Various methods for managing the capacitor voltage balance are presented and discussed, including operation in different regions, with different numbers of phases and levels. The techniques for capacitor voltage balance in DC-DC conversion are also discussed. The paper concludes with application examples demonstrating the benefits of the presented techniques.
Article
Energy & Fuels
Pablo Poblete, Sebastian Neira, Ricardo P. Aguilera, Javier Pereda, Josep Pou
Summary: The proposed sequential phase-shifted model predictive control (PS-MPC) effectively tackles the issues of high computational complexity and variable switching frequency in controlling MMCs. By utilizing phase-shifted pulsewidth modulation technique, this control strategy achieves independent optimal modulating signals for each carrier, allowing for multiple objective control.
IEEE TRANSACTIONS ON ENERGY CONVERSION
(2021)
Article
Automation & Control Systems
Xiaonan Gao, Wei Tian, Yuebin Pang, Ralph Kennel
Summary: In this article, a model-predictive control method for modular multilevel converters (MMCs) operating in a wide frequency range is proposed. A novel cost function is designed to achieve output current control and voltage balancing control for both low- and high-frequency operations. Compared with traditional methods, this proposed method can easily achieve a tradeoff between modulation range and amplitude of injected common-mode voltage under different operating conditions, and the control structure is more straightforward. Experimental results verify the effectiveness and superiority of the proposed method.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Shiyuan Fan, Xin Xiang, Jing Sheng, Yunjie Gu, Huan Yang, Wuhua Gae Li, Xiangning He, Tim C. Green
Summary: This article extends the inherent balance concept previously shown for square-wave modulation to a multilevel version for MMDCs. By introducing a switching duty matrix, the inherent voltage balance is ensured. The study develops a generalized coprime criterion based on circulant matrix theory and verifies the effectiveness of the proposed circulant modulation through simulations and experiments in achieving SM voltage balance in an MMDC.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Tiago de Sa Ferreira, Guilherme Monteiro de Rezende, Lenin Martins Ferreira Morais, Victor Flores Mendes, Didier Flumian, Jeremi Regnier, Thierry A. Meynard
Summary: The series and parallel multicell converters offer advantages in efficiency, power density, and dynamic response. Interleaving control patterns and utilizing a multi-rate modulation strategy can improve the dynamic response speed.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Energy & Fuels
Mario Lopez, Hendrik Fehr, Marcelo A. Perez, Albrecht Gensior
Summary: In this study, the stationary operation of a modular multilevel converter is optimized by calculating the Pareto frontier of arm energy ripple and conduction losses for different operating conditions. The best trade-off between energy ripple and power losses can be chosen from a set of optimal solutions, allowing for the optimization of efficiency and reduction of capacitor voltage ripple and circulating current, which leads to a decrease in size and cost. The theoretical analysis and results are experimentally validated on a prototype test-bench.
Review
Energy & Fuels
Alvaro Carreno, Marcelo Perez, Carlos Baier, Alex Huang, Sanjay Rajendran, Mariusz Malinowski
Summary: Distribution systems face constant stress from variable operating conditions, impacting distribution transformers and lines and degrading end-user service quality. Hybrid transformers, composed of a conventional transformer and a power converter, offer an interesting alternative to address multiple power quality issues.
Article
Energy & Fuels
Felipe A. Villarroel, Jose R. Espinoza, Marcelo A. Perez, Roberto O. Ramirez, Carlos R. Baier, Daniel Sbarbaro, Jose J. Silva, Mauricio A. Reyes
Summary: Finite Control Set Model Predictive Control (FCS-MPC) is an alternative to conventional linear controllers in power converters, offering attractive features. However, using a short prediction horizon FCS-MPC in certain topologies may lead to control issues, which can be addressed by nonlinear control theory.
IEEE TRANSACTIONS ON ENERGY CONVERSION
(2021)
Article
Engineering, Electrical & Electronic
Jiapeng Yin, Jose Leon, Marcelo A. Perez, Leopoldo G. Franquelo, Abraham Marquez, Sergio Vazquez
Summary: The article proposes a low-cost MPC technique for MMCs to address the issue of high calculation involved in FCS-MPC. The arm voltage references for each phase are determined analytically, simplifying the optimization problem-solving process. Experimental tests show that this method has a clear advantage in terms of calculation cost while achieving similar performance.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Energy & Fuels
Henry M. Zapata, Marcelo A. Perez
Summary: This paper presents a modular multilevel converter for a linear generator in a wave energy converter. The individual control of the coils in this generator enhances energy harvesting performance. The converter is designed with two stages, the first one for controlling the harvested current and the second one for controlling the DC-link voltage and output current. Additionally, the multilevel modular converter allows the generation of a moderate DC voltage, reducing energy losses in transmission lines.
Article
Chemistry, Analytical
Jaime Rohten, Felipe Villarroel, Esteban Pulido, Javier Munoz, Jose Silva, Marcelo Perez
Summary: This paper analyzes the voltage deviations in distributed power generation, micro-grids, and networks working in islanding mode. While amplitude deviations have been widely studied, deviations in AC mains frequency have received less attention. The paper presents a comprehensive analysis of control system stability under a wide variable grid frequency, specifically focusing on a back-to-back static converter topology. The findings highlight the importance of using a dynamic decoupler to extend the operating window of power converters.
Article
Energy & Fuels
Henry M. Zapata, Marcelo A. Perez, Abraham Marquez Alcaide
Summary: This paper proposes a control scheme for wave energy conversion system, where a linear generator and a cascaded multilevel converter are used. The mechanical conversion system consists of a buoy connected directly to a linear generator. The generator windings are controlled individually by a cascaded multilevel power converter using maximum power point tracking. The cascaded converter output is controlled to balance the DC capacitors and generate a multilevel voltage at the output terminals, reducing losses in the underwater transmission line. Experimental results show that the proposed control scheme maximizes power generation by imposing a current with the same waveform as the induced voltage and balancing the DC capacitors.
Article
Computer Science, Information Systems
Carlos R. Baier, Felipe A. Villarroel, Miguel A. Torres, Marcelo A. Perez, Jesus C. Hernandez, Eduardo E. Espinosa
Summary: Small grid-connected inverters do not support the electrical grid during contingency events due to their low power capacity. It is beneficial for microgrids and weak grids if all grid-connected converters could provide support against frequency disturbances. Among small grid-connected converters, single-phase quasi-Z-source inverters (QZSI) are attractive due to their reliability and efficiency for small to medium power applications. However, a major challenge is managing both DC and AC variables with the same group of switches. This paper proposes a finite control set model predictive control (FCS-MPC) strategy for a single-phase grid-supporting QZSI, which demonstrates the feasibility of providing grid frequency support.
Article
Engineering, Multidisciplinary
Javier Samanes, Leyre Rosado, Eugenio Gubia, Jesus Lopez, Marcelo A. Perez
Summary: In this paper, we propose a deadbeat control strategy of the capacitor voltage for high power converters with LCL filter, which includes an active damping strategy based on a modification of the deadbeat control law to damp the LCL resonant poles. A notch filter is applied to the electrical variables to emulate different damping resistances for the fundamental component and the harmonics. Experimental results validate the proposed strategy.
IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS
(2023)
Article
Engineering, Multidisciplinary
Zisui Zhang, Sumedh Dhale, Babak Nahid-Mobarakeh, Ali Emadi
Summary: An adaptive voltage controller scheme is proposed in this paper for flux-weakening control in Permanent Magnet Synchronous Machine (PMSM) drives under the six-step operation. The presented technique utilizes voltage feedback control to fully utilize the DC link voltage, thus extending the maximum torque range in the flux-weakening region. The behavior of the voltage controller is analyzed under the modulation delay and nonlinear gain characteristics of six-step operation, and compensatory control action is generated with varying voltage feedback gains based on the magnitude difference between voltage vectors to achieve a greater torque range and higher efficiency in the flux-weakening zone. The effectiveness of the proposed technique is verified through simulation and experimental results on a PMSM drive platform.
IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Marco Liserre, Marcelo A. Perez, Marius Langwasser, Christian A. Rojas, Ziqi Zhou
Summary: This article discusses the transformation of power systems driven by the integration of renewable energy sources and variable loads, and the role of power electronics in enabling flexible power processing. The article explores the potential of system-level power electronics solutions, such as smart transformers and high-voltage direct current transmission, in increasing the capacity of existing grid assets, reducing upgrade costs, and enhancing the capability of electric grid infrastructures through smart grid tools.
PROCEEDINGS OF THE IEEE
(2023)
Article
Computer Science, Information Systems
Diego S. D'Antonio, Oswaldo Lopez-Santos, Alex Navas-Fonseca, Freddy Flores-Bahamonde, Marcelo A. Perez
Summary: In this paper, a multi-mode master-slave control approach is proposed to enhance the flexibility of DC-coupled hybrid microgrids. The control scheme allows optimal coordination among power units and buses, ensuring reliable operation. Furthermore, it considers the expansion of microgrid capacity, providing more degrees of freedom for optimization and control.
Proceedings Paper
Engineering, Electrical & Electronic
Albert Cirera, Ioannis Vourkas, Antonio Rubio, Marcelo Perez
Summary: Advances in ReRAM technology show promise for future computing systems. This study explores the use of noise and stochastic resonance to mitigate the impact of behavioral variability, and finds that adding appropriate amplitude of noise can improve the Bit Error Rate (BER) metric in ReRAM memory applications.
2022 IEEE 22ND INTERNATIONAL CONFERENCE ON NANOTECHNOLOGY (NANO)
(2022)
Article
Computer Science, Information Systems
Felipe A. Villarroel, Jose R. Espinoza, Marcelo A. Perez, Carlos R. Baier, Jaime A. Rohten, Roberto O. Ramirez, Esteban S. Pulido, Jose J. Silva
Summary: This paper proposes a new concept for a predictive horizon one voltage controller for grid-connected three-phase active front end rectifiers, addressing the stability issues that may arise when directly inverting the non-minimum phase voltage dynamic. By utilizing the minimum and non-minimum phase plant factorization concept and the use of different sampling periods, the proposed method ensures the fastest response of the system for a given sampling time.
Article
Engineering, Electrical & Electronic
Marcelo A. Perez, Salvador Ceballos, Georgios Konstantinou, Josep Pou, Ricardo P. Aguilera
Summary: The modular multilevel converter (MMC) is a power converter topology that has attracted global research and development, offering high quality voltages and currents, modularity, and high voltage rating. However, its unique features like a large number of submodules, floating capacitor voltages, and circulating currents present challenges that require a dedicated control system with high dynamical performance.
IEEE OPEN JOURNAL OF THE INDUSTRIAL ELECTRONICS SOCIETY
(2021)
