DEELT - Departamento de Engenharia Elétrica

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/5266

Navegar

Resultados da Pesquisa

Agora exibindo 1 - 7 de 7
  • Imagem de Miniatura
    Item
    Power-sharing for dc microgrid with composite storage devices and voltage restoration without communication.
    (2022) Bastos, Renan Fernandes; Aguiar, Cassius Rossi de; Balogh, Attila; Sütő, Zoltán; Machado, Ricardo Quadros
    In this paper, we propose a new decentralized control and power-sharing strategy to manage the power flow among energy sources (ESs), energy storage systems (ESSs) and the common dc-link. In the proposed technique, we eliminate all communication among the ESSs, to reduce the complexity and increase reliability, maintaining dc-link voltage restoration. In this context, batteries and ultracapacitors (UCs) are the ESSs, while ESs can be any power source such as photovoltaic, wind, fuel-cell and etc. This technique shares the microgrid power imbalance between batteries, proportionally to their state-of-charge (SoC) and energy capacity, achieving SoC equalization. The technique also promotes voltage restoration for the UCs, keeping their average voltage constant after supplying the power peaks during power transients. For all ESSs only local variables are measured, such as local current and dc-link voltage, with no shared data between ESSs. Small signal and stability analysis are performed, along with experimental results in a lab bench show the feasibility and performance of the technique.
  • Imagem de Miniatura
    Item
    Low-cost hardware-in-the-loop for real-time simulation of electric machines and electric drive.
    (2020) Bastos, Renan Fernandes; Silva, Fernando Bento; Aguiar, Cassius Rossi de; Fuzato, Guilherme Henrique Favaro; Machado, Ricardo Quadros
    This study aims to present the discrete models and the methodology to implement real-time simulations of electric machines using a low-cost digital signal processor (DSP). The DC machine and the three-phase induction machine are modelled in real-time using a Texas Instruments DSP TMS28379D, where the discrete models are implemented using C language. A minimum time-step of 1 μs can be achieved for the DC machine and 1.5 μs for the inductions machine in the experimental hardware. To validate the described models and show their precision, they are compared with commercial computational models from PSIM®. In addition, closed-loop speed control strategies are applied to the real-time DSP experimental models, showing perfect concordance with the machine theory. For the DC machine, a speed control strategy with an inner current control loop is applied and for the induction machine, a field-oriented control for the speed control. The proposed real-time simulation hardware has a great potential for low-budget research and educational purposes since it can replace a real machine setup for a very low price, with great accuracy, variable parameters and free from risks, such as accidents or equipment damage. Furthermore, it uses cheap hardware with free software and a high-level programing language.
  • Imagem de Miniatura
    Item
    Cascaded interleaved DC–DC converter designed for grid-to-vehicle and vehicle-to-grid technologies.
    (2021) Leal, Wagner Coelho; Bastos, Renan Fernandes; Aguiar, Cassius Rossi de; Godinho, Marcelo Oliveira; Fuzato, Guilherme Henrique Favaro; Piardi, Artur Bohnen; Braggio, Almir Augusto; Sonoda, Dabit G.; Otto, Rodrigo Bueno; Nadal, Zeno L. I.; Machado, Ricardo Quadros
    This paper presents a study of a cascaded bidirectional interleaved DC–DC converter applied to an electric charging station, which uses grid-to-vehicle (G2V) and vehicle-to-grid (V2G) technologies. In this context, the interleaved technique is used to reduce the current ripple through the battery of the electric vehicle (EV), which can also absorb or deliver power to the microgrid. Additionally, the small-signal technique is also employed to calculate the gains of the PI controllers for charging and discharging the EV battery. Finally, this paper presents a set of simulations using the software PSIM® and experimental results using a low-cost hardware-in-the-loop (HIL) to support the theoretical study and to demonstrate the effectiveness of the proposed approach.
  • Imagem de Miniatura
    Item
    Low-cost hardware-in-the-loop for real-time simulation of electric machines and electric drive.
    (2020) Bastos, Renan Fernandes; Silva, Fernando B.; Aguiar, Cassius Rossi de; Fuzato, Guilherme Henrique Favaro; Machado, Ricardo Quadros
    This study aims to present the discrete models and the methodology to implement real-time simulations of electric machines using a low-cost digital signal processor (DSP). The DC machine and the three-phase induction machine are modelled in real-time using a Texas Instruments DSP TMS28379D, where the discrete models are implemented using C language. A minimum time-step of 1 µs can be achieved for the DC machine and 1.5 µs for the inductions machine in the experimental hardware. To validate the described models and show their precision, they are compared with commercial computational models from PSIM®. In addition, closed-loop speed control strategies are applied to the real-time DSP experimental models, showing perfect concordance with the machine theory. For the DC machine, a speed control strategy with an inner current control loop is applied and for the induction machine, a field-oriented control for the speed control. The proposed real-time simulation hardware has a great potential for low-budget research and educational purposes since it can replace a real machine setup for a very low price, with great accuracy, variable parameters and free from risks, such as accidents or equipment damage. Furthermore, it uses cheap hardware with free software and a high-level programing language.
  • Imagem de Miniatura
    Item
    Model, design and implementation of LCC converter for power generation and distributed generation.
    (2019) Bastos, Renan Fernandes; Dias, André Lage Almeida; Machado, Ricardo Quadros
    This paper proposes to model, design and implement a LCC (Line Commuted Converter) for power generation purpose, using alternative sources such as photovoltaic panel (PV), fuel cell and permanent magnet synchronous machine as the main power source. The converter is built with a full bridge twelve-pulse thyristor topology and connected to the alternative source through a line reactor. In order to extract maximum power from the sources, a classical maximum power point tracking algorithm (MPPT P&O) is applied. To validate the theoretical and simulated analysis, a 600 W experimental setup was built and controlled in closed loop. For the experimental results, the alternative source was represented by a variable DC power source in series with a resistor, making it possible to create controlled power steps and power events. During the operation, the grid current is analyzed in terms of power quality and an islanding event was created to analyze the converter’s behavior under critical conditions. All the experimental results show perfect conformity with the theory and simulation, proving the effectiveness of this converter topology for this purpose.
  • Imagem de Miniatura
    Item
    Model, design and implementation of a lowcost HIL for power converter and microgrid emulation using DSP.
    (2019) Bastos, Renan Fernandes; Fuzato, Guilherme Henrique Favaro; Aguiar, Cassius Rossi de; Neves, Rodolpho Vilela Alves; Machado, Ricardo Quadros
    In this study, the authors propose a method to implement a low-cost hardware-in-the-loop (HIL) system for power converters and microgrids design, test and analysis. This approach uses a digital signal processor (DSP) Texas Instruments as the HIL core. All the differential equations of the power converters are solved in real-time by the DSP and displayed in the digital-to-analogue outputs. Three different converters are modelled in this study: boost converter, single-phase inverter connected to the grid and three-phase inverter connected to the grid. Experimental results are obtained and compared to the HIL response. These results were made triggering the real converter and the HIL with the same open-loop pulse width modulation signal, showing high fidelity between the digital models over the real systems. In a second moment, a microgrid is modelled in the proposed HIL and tested with a closed-loop controller. The experiments show that the proposed hardware supports time steps as low as 1 μs or 1 MHz update rate, depending on the model. The proposed technique has the potential to reduce testing time and cost, once commercial HIL devices such as Typhoon, dSPACE and RTDS have a significant cost, not affordable or available to all the research community
  • Imagem de Miniatura
    Item
    Voltage gain analysis of the interleaved boost with voltage multiplier converter used as electronic interface for fuel cells systems.
    (2016) Fuzato, Guilherme Henrique Favaro; Aguiar, Cassius Rossi de; Ottoboni, Klebber de Araujo; Bastos, Renan Fernandes; Machado, Ricardo Quadros
    The connection of low power renewable energy sources, such as fuel cells, to the distribution generation system requires power electronics structures with high voltage gain, high capability to power processing and consequently, high levels of current flowing through the dc/dc converter. In this context, this study analyses how the parasitic resistances of the passive components and the load power demand affect the dc/dc converter voltage gain. Taking into account the mathematical model, the boundaries of operation of the Interleaved Boost with Voltage Multiplier converter is determined through a set of equations and by means of a graphical analysis. The theoretical analysis, simulations and experimental results are used to validate the proposed approach presented in this study.