G. Escobar, Pánfilo R. Martínez-Rodríguez, Carl Ngai Man Ho, José M. Sosa,
This paper presents the design of a current reference used in an inverter-side current controller for a grid-connected single-phase transformerless inverter with an Inductive-Capacitive-Inductive of LCL filter. The idea is to indirectly control the inverter-side current, by directly acting on the grid-side current. Furthermore, it can be shown that the simple proportional term guarantees damping injection. However, the design of the current reference for such a controller is a more involved process, ...
Tópico(s): Islanding Detection in Power Systems
2017 - Wiley | International Transactions on Electrical Energy Systems
G. Escobar, Pánfilo R. Martínez-Rodríguez, Samuel Iturriaga‐Medina, Jonathan C. Mayo‐Maldonado, Jorge Lopez-Sarabia, O. Micheloud,
This article studies the benefits of the virtual-ground (VG) connection for single-phase transformerless grid-tied inverters, which is used to mitigate the leakage-ground currents (LGCs) issue. This article also proposes common-mode and differential-mode models of single-phase inverters connected to the grid through an $LCL$ output filter, which are used as a theoretical support. It is shown that LGCs are simply common-mode currents (CMCs) circulating through the ground path, which represents a contribution ...
Tópico(s): Advanced DC-DC Converters
2019 - Institute of Electrical and Electronics Engineers | IEEE Journal of Emerging and Selected Topics in Power Electronics
A. Fernández, G. Escobar, Pánfilo R. Martínez-Rodríguez, José M. Sosa, Daniel U. Campos‐Delgado, Manuel J. López-Sánchez,
... for more papers by this authorGerardo Escobar, Gerardo Escobar School of Engineering, UADY, Merida, Yucatan, 97310 MexicoSearch for more papers by this authorPanfilo R. Martinez-Rodriguez, Panfilo R. Martinez-Rodriguez School of Sciences, UASLP, SLP ... for more papers by this authorGerardo Escobar, Gerardo Escobar School of Engineering, UADY, Merida, Yucatan, 97310 MexicoSearch for more papers by this authorPanfilo R. Martinez-Rodriguez, Panfilo R. Martinez-Rodriguez School of Sciences, UASLP, SLP ...
Tópico(s): Multilevel Inverters and Converters
2017 - Institution of Engineering and Technology | IET Power Electronics
A. Fernández, Pánfilo R. Martínez-Rodríguez, G. Escobar, Cesar A. Limones-Pozos, José M. Sosa,
This paper presents the modeling and control processes of the single-phase cascade H-bridge multilevel converter used as a shunt active filter. Based on the obtained model, a controller is proposed to compensate for harmonic distortion and reactive power caused by a nonlinear load. These issues are solved by guaranteeing tracking of the line current toward an appropriately defined current reference. In the proposed approach, the current reference has been selected to be a signal proportional to ...
Tópico(s): Microgrid Control and Optimization
2012 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Industrial Electronics
Pánfilo R. Martínez-Rodríguez, G. Escobar, A. Fernández, M. Hernández-Gómez, José M. Sosa,
This paper presents a model-based controller for the direct control of real and reactive powers in a three-phase three-wire rectifier. As the unbalanced operation is considered, it is convenient to express the grid voltage in terms of both positive and negative sequences, in order to obtain a more complete description of the system. In particular, the positive sequence of the grid voltage is used as the transformation basis to reconstruct the average, i.e., a particular subset, of the conventional ...
Tópico(s): Advanced DC-DC Converters
2013 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Industrial Electronics
Gerardo Vázquez, Pánfilo R. Martínez-Rodríguez, G. Escobar, José M. Sosa, Rigoberto Martínez-Méndez,
A single-phase cascade multilevel inverter is able to synthesize AC output voltages with considerably reduced harmonic distortion, which results in reduced size output filters. In addition, the amplitude of the output voltage in the cascade multilevel inverter topology is usually higher than in a single H-Bridge inverter, which makes possible the power injection into the grid without a voltage boost stage. These benefits make cascade multilevel inverter a suitable topology for PV applications. However, ...
Tópico(s): Silicon Carbide Semiconductor Technologies
2016 - Wiley | International Transactions on Electrical Energy Systems
Pánfilo R. Martínez-Rodríguez, G. Escobar, José M. Sosa, Gerardo Vázquez-Guzmán, Jose de Jesus Mendoza-Mendoza,
In this paper, a controller for a shunt active power filter based on a 3-level neutral point clamped inverter is presented. The proposed controller guarantees compensation of harmonic and reactive powers caused by nonlinear loads connected at the point of common coupling. The controller comprises three control loops, namely, a current tracking loop, a voltage regulation loop, and a voltage balance loop. The current tracking loop is aimed to inject the appropriate current by means of the power inverter ...
Tópico(s): Microgrid Control and Optimization
2017 - Wiley | International Transactions on Electrical Energy Systems
Juan F. Martinez‐Garcia, Pánfilo R. Martínez-Rodríguez, G. Escobar, Gerardo Vázquez-Guzmán, José M. Sosa, A. Fernández,
In this paper, a comparative study of modulation techniques used in a transformerless H-bridge neutral point clamped (HB-NPC) multilevel inverters is presented. Transformerless inverters, usually found in photovoltaic (PV) applications, are more efficient and economically affordable than isolated systems. Nevertheless, they may cause leakage ground currents. The latter are produced by the stray capacitances formed between the PV panel frame and the ground path. There are different ways to overcome ...
Tópico(s): Microgrid Control and Optimization
2019 - Institution of Engineering and Technology | IET Renewable Power Generation
José M. Sosa, Pánfilo R. Martínez-Rodríguez, G. Escobar, Gerardo Vázquez, A. Fernández, Juan F. Martinez‐Garcia,
Transformerless grid-connected inverters offer greater efficiencies when transferring power from renewable energy sources to the electrical grid. If the grid-inverter connection is done with an LCL filter, high attenuation of switching harmonics is achieved while preserving a small-size output filter. However, damping must be included in the controller to assure closed-loop stability. This paper proposes a reference computation methodology for the inverter-side current feedback in a photovoltaic ( ...
Tópico(s): Smart Grid Energy Management
2020 - Springer Nature | Journal of Modern Power Systems and Clean Energy
José M. Sosa, Pánfilo R. Martínez-Rodríguez, G. Escobar, Gerardo Vázquez, A. Fernández,
This paper presents the design, implementation, and evaluation of a model-based controller for a general scheme of transformerless power converters connected to the grid through an L filter. The proposed controller is aimed at active power injection, and consists of a damping term over the current error in addition to a filter parameter estimation scheme. The latter provides estimates of the filter internal resistance and inductance values. It involves the fundamental and quadrature components of ...
Tópico(s): Advanced DC-DC Converters
2017 - Taylor & Francis | Electric Power Components and Systems
G. Escobar, Pánfilo R. Martínez-Rodríguez, Samuel Iturriaga‐Medina, Gerardo Vázquez-Guzmán, José M. Sosa, Diego Langarica-Córdoba,
This work presents the design of a control law based on the average model of a shunt active power filter considering an H-bridge neutral point clamped topology and its experimental validation. Therefore, the proposed controller is formed by three control loops, namely current (inner), regulation (outer), and balance control loops. The current loop aims to compensate both the displacement power factor and the harmonic distortion produced by nonlinear loads connected to the point of common coupling. ...
Tópico(s): Advanced DC-DC Converters
2020 - Multidisciplinary Digital Publishing Institute | Energies
Julio C. Rosas‐Caro, G. Escobar, Pánfilo R. Martínez-Rodríguez, Samuel Iturriaga‐Medina, Jonathan C. Mayo‐Maldonado, Jesús E. Valdez-Reséndiz,
This paper studies the double-dual DC-DC buck converter composed by two buck power stages in a double dual connection. This connection has been previously studied with the boost power stage in the well-known double dual boost converter. In contrast to the double dual boost, which can only be used as a dc-dc converter, the double dual buck can be used as an inverter. Furthermore, it has a non-pulsating voltage from the input terminals to the output terminals. This property is exploited to reduce ...
Tópico(s): Microgrid Control and Optimization
2021 - Elsevier BV | International Journal of Electrical Power & Energy Systems
G. Escobar, A. Fernández, J. Leyva-Ramos, Pánfilo R. Martínez-Rodríguez,
An adaptive controller for the compensation of output voltage ripple due to harmonic distortion in the input voltage is proposed for a pulse width modulated (PWM) boost converter. Following the Lyapunov approach, we designed an adaptive law to cope with uncertainties in the disturbance signals and parameters. Complexity of the proposed controller is reduced by rotations which transform the adaptive terms into a sum of resonant filters tuned at the frequencies of the harmonics under compensation, ...
Tópico(s): Vibration and Dynamic Analysis
2004 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Control Systems Technology
G. Escobar, Paolo Mattavelli, M. Hernández-Gómez, Pánfilo R. Martínez-Rodríguez,
This paper proposes some modifications aimed for the practical implementation of repetitive-based schemes used in harmonic distortion compensation schemes. Practical implementation of repetitive schemes requires both to limit the gain originally infinite and to restrict the bandwidth of the controller originally of infinite dimension. Roughly speaking, each delay line in the repetitive scheme must include an associated limiting gain and a low-pass filter (LPF). However, it has been observed that ...
Tópico(s): Piezoelectric Actuators and Control
2013 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Industrial Electronics
Juan F. Martinez‐Garcia, Gerardo Vázquez-Guzmán, Pánfilo R. Martínez-Rodríguez, G. Escobar, A. Fernández, José M. Sosa,
Single-phase transformerless inverters are widely installed in grid connected photovoltaic systems due to their outstanding advantages, namely, high efficiency, low cost and high power density. The lack of galvanic isolation leads to common-mode voltage (or current) issues, which are solved by means of modifications to topologies, control schemes and modulation strategies. This study proposes a novel multilevel inverter for single-phase transformerless photovoltaic systems. The topology is based ...
Tópico(s): Silicon Carbide Semiconductor Technologies
2020 - Institution of Engineering and Technology | IET Power Electronics
Samuel Iturriaga‐Medina, Pánfilo R. Martínez-Rodríguez, G. Escobar, Gerardo Vázquez-Guzmán, Diego Langarica-Córdoba, Julio C. Rosas‐Caro, José M. Sosa, Jonathan C. Mayo‐Maldonado,
In this article, a solution to mitigate the leakage-ground currents (LGCs) in a grid-tied H-bridge neutral-point-clamped inverter is presented. This solution consists in splitting the $LC$ filter capacitor and connecting each capacitor to a dc-link terminal. The proposal is referred to as the dc-link-tied $LC$ output filter. Out of this hardware modification, it is not necessary to increase the number of switches nor design a new modulation scheme. Furthermore, a formal analysis is provided based on ...
Tópico(s): Advanced DC-DC Converters
2021 - Institute of Electrical and Electronics Engineers | IEEE Journal of Emerging and Selected Topics in Power Electronics
Jorge L. Lopez-Sarabia, G. Escobar, Pánfilo R. Martínez-Rodríguez, Samuel Iturriaga‐Medina, Jonathan C. Mayo‐Maldonado, Dunstano del Puerto-Flores,
This article presents a control method to balance, in average, the dc-link capacitor voltages while injecting power to the grid using an h-bridge neutral-point clamped five-level inverter grid tied through an inductor–capacitor–inductor (LCL) filter. The method exploits the structure of a particular model representation of the system comprising a differential-mode (DM) part and a common-mode (CM) part, which turn out to be decoupled from one another. These decoupled representations enormously facilitate ...
Tópico(s): Advanced DC-DC Converters
2021 - Institute of Electrical and Electronics Engineers | IEEE Journal of Emerging and Selected Topics in Power Electronics
G. Escobar, Gerardo Vázquez-Guzmán, Erick I. Pool-Mazun, Pánfilo R. Martínez-Rodríguez, Manuel J. López-Sánchez, José M. Sosa,
This paper presents a transformerless single-phase inverter topology based on a modified H-bridge-based multilevel converter. The topology comprises two legs, namely, a usual two-level leg and a T-type leg. The latter is based on a usual two-level leg, which has been modified to gain access to the midpoint of the split dc-link by means of a bidirectional switch. The topology is referred as an asymmetrical T-type five-level (5L-T-AHB) inverter. An ad hoc modulation strategy based on sinusoidal pulsewidth ...
Tópico(s): Silicon Carbide Semiconductor Technologies
2017 - Institute of Electrical and Electronics Engineers | IEEE Journal of Emerging and Selected Topics in Power Electronics
A. Fernández, G. Escobar, Daniel U. Campos‐Delgado, Kassim O. Mtepele, Pánfilo R. Martínez-Rodríguez,
This work introduces a generalized methodology for mathematical modelling and controller design of a single-phase cascaded H-bridge multilevel-converter comprising the connection of N H-bridges, which results in 2N+1 voltage levels. Towards this end, the average model of the converter is first transformed into a decoupled mathematical structure based on a new definition of state variables. Out of this, the control objectives, current tracking and voltage regulation, are decoupled from the voltage ...
Tópico(s): HVDC Systems and Fault Protection
2020 - Elsevier BV | International Journal of Electrical Power & Energy Systems
Gerardo Vázquez-Guzmán, Pánfilo R. Martínez-Rodríguez, J. A. Verdin, G. Escobar, Alejandro Rolán, Diego Langarica-Córdoba, Samuel Iturriaga‐Medina, Jorge L. Lopez-Sarabia,
The transformerless inverters for photovoltaic systems are widely used as it features low cost, volume, and weight. Thus, in recent years, its study has been of great interest to the research community. In this paper a transformerless cascade multilevel inverter for photovoltaic applications with leakage ground current compensation capability is presented. The proposed solution involves a second-order LC output filter with a particular connection, which is referred to as the DC-link-tied LC output ...
Tópico(s): Advanced DC-DC Converters
2022 - Institute of Electrical and Electronics Engineers | IEEE Access
Pánfilo R. Martínez-Rodríguez, José M. Sosa, Samuel Iturriaga‐Medina, G. Escobar, Gerardo Vázquez-Guzmán, A. Fernández,
This paper addresses the control design and the experimental validation of a current mode control for a three phase voltage source rectifier. The proposed control law is able to fulfill the voltage regulation and the current tracking control objectives despite of unbalanced and distorted grid voltages. The proposed control law consists of two loops, which are referred as inner tracking loop and the outer voltage regulation loop. The inner loop is designed to provide damping to the system, which ...
Tópico(s): Advanced DC-DC Converters
2018 - Springer Nature | Journal of Modern Power Systems and Clean Energy
Samuel Iturriaga‐Medina, Pánfilo R. Martínez-Rodríguez, G. Escobar, C. A. Soriano-Rangel, Diego Langarica-Córdoba, Gerardo Vázquez-Guzmán, Jorge L. Lopez-Sarabia,
A control design for an HB-NPC transformerless inverter is presented in this paper, the proposal includes a modified LCL passive output filter which is aimed to attenuate leakage-ground currents in a transformerless photovoltaic generation system. This modification consists of a simple connection of the filter capacitors to the positive and negative nodes of the DC-link. A theoretical analysis of the differential-mode and common-mode models is performed. Thus, the proposed control law is designed ...
Tópico(s): Advanced DC-DC Converters
2022 - Elsevier BV | International Journal of Electrical Power & Energy Systems
Samuel Iturriaga‐Medina, Pánfilo R. Martínez-Rodríguez, G. Escobar, C. A. Soriano-Rangel, D. Langarica-Cordova, Gerardo Vázquez-Guzmán, Jorge L. Lopez-Sarabia,
A control design for an HB-NPC transformerless inverter is presented in this paper, the proposal includes a modified LCL passive output filter which is aimed to attenuate leakage--ground currents in transformerless photovoltaic generation system. This modification consists of a simple connection of the filter capacitors to the positive and negative nodes of the dc--link. A theoretical analysis on the differential--mode and common--mode models is performed. Thus the proposed control law is designed ...
Tópico(s): Advanced DC-DC Converters
2022 - RELX Group (Netherlands) | SSRN Electronic Journal
G. Escobar, Luis Ibarra, M. Hernández-Gómez, Pánfilo R. Martínez-Rodríguez, Jesús E. Valdez-Reséndiz, Daniel Guillén,
This work presents a model-based frequency-locked loop (FLL) for three-phase systems subject to unbalance and harmonic distortion conditions. It is based on a pretty general model of a three-phase AC reference signal comprising a set of harmonic oscillators. Likewise, the proposed synchronization scheme comprises a set of adaptive harmonic oscillators to estimate the corresponding harmonic components. The proposed scheme considers three different types of harmonic oscillators that distinguish among ...
Tópico(s): Power Quality and Harmonics
2021 - Institute of Electrical and Electronics Engineers | IEEE Access