Juan M Ramirez | Centro de Investigacion y Estudios Avanzados del IPN (original) (raw)

Papers by Juan M Ramirez

Electronics

This paper presents a versatile, low-cost real-time control platform with embedded isolated input... more This paper presents a versatile, low-cost real-time control platform with embedded isolated inputs and outputs for direct usage in electrical applications. The inputs correspond to voltage and current measurements, while the outputs are digital signals with isolated power supply. The validation for the platform considers the implementation of the power electronics topologies where the control algorithms are implemented in Simulink. The topologies are the interleaved three-phase buck converter, push–pull converter, H-bridge, and thyristor-based AC load controller. The control for them involves voltage feedback, current feedback, linear control algorithms, and the implementation of a discrete PLL algorithm for the last topology. Hence, the platform demonstrates the effectiveness of performing real-time control for some power electronics topologies.

Mathematical Problems in Engineering, 2020

Selective harmonics elimination (SHE) is a widely applied control strategy in multilvel inverters... more Selective harmonics elimination (SHE) is a widely applied control strategy in multilvel inverters for harmonics reduction. SHE is designed for the elimination of low-order harmonics while keeping the fundamental component equal to any previously specified amplitude. This paper proposes a novel bio-inspired metaheuristic optimization algorithm called Black Widow Optimization Algorithm (BWOA) for solving the SHE set of equations. BWOA mimics the spiders’ different movement strategies for courtship-mating, guaranteeing the exploration and exploitation of the search space. The optimization results show the reliability of BWOA compared to the state-of-the-art metaheuristic algorithms and show competitive results as a microalgorithm, opening its future application for an on-line optimization calculation in low requirement hardware.

Applications of MATLAB in Science and Engineering, 2011

Energies, 2022

A small prototype of a 5-level single-phase full H-bridge inverter for ocean current applications... more A small prototype of a 5-level single-phase full H-bridge inverter for ocean current applications is presented. The inverter was designed applying level-shift control in pulse-width modulation (LS-PWM), and experimental tests were conducted using a variety of modulation subschemes, including in-phase disposition (IPD), alternate-phase opposition–disposition (APOD), and phase opposition–disposition (POD). The test results were examined for harmonic content and voltage total harmonic distortion (THDV). The results suggest that the inverter presents a viable solution with significant potential for the development of a larger three-phase inverter model that can be used to connect ocean current power sources to the electrical grid.

Mathematics, 2021

This manuscript presents the numerical optimization (through a mathematical model and an evolutio... more This manuscript presents the numerical optimization (through a mathematical model and an evolutionary algorithm) of the voltage-doubler boost converter, also called the series-capacitor boost converter. The circuit is driven by two transistors, each of them activated according to a switching signal. In the former operation, switching signals have an algebraic dependence from each other. This article proposes a new method to operate the converter. The proposed process reduces the input current ripple without changing any converter model parameter, only the driving signals. In the proposed operation, switching signals of transistors are independent of each other, providing an extra degree of freedom, but on the other hand, this produces an infinite number of possible combinations of duty cycles (the main parameter of switching signals) to achieve the desired voltage gain. In other words, this leads to a problem with infinite possible solutions. The proposed method utilizes an evolutio...

Heliyon, 2019

The design and implementation of a solar tracker based on panoramic images captured by a fisheye ... more The design and implementation of a solar tracker based on panoramic images captured by a fisheye camera are proposed. Such images receive a digital treatment to estimate the sun azimuth and the elevation angles. These angles are fed to a microcontroller, handling an accelerometer with a gyroscope, that positions the solar tracker to the angle of solar elevation and a compass to set the azimuth angle concerning the north, either magnetic or geographic. The proposed system works satisfactorily to guide the solar tracker regardless of whether it is a sunny or cloudy day.

Renewable and Sustainable Energy Reviews, 2016

The electric generation systems on islands are based generally on fossil fuel. This fact and its ... more The electric generation systems on islands are based generally on fossil fuel. This fact and its supply make the electricity cost higher than in systems used in the continent. In this article, we present a review of the renewable energy generation systems on islands. To do it we analysed 77 islands from 45 different countries. This work will allow us to know how the implementation of renewable energy sources could help these islands in developing a renewable and sustainable energy sector, including a reduction of electricity generation cost. This paper shows the results from a study case of the application of renewable energy technology in Cozumel Island, Mexico. This Island is located in front of the Riviera Maya area. The analysis was made through long-term statistical models. A deterministic methodology was used to perform time-series simulations. The simulations shows that for the year 2050 a feasible integration of a system based on wind/PV can be achieved on the Island, reducing the electricity price from 0.37 US$/kWh to 0.24 US$/kWh (2050 scenario). With this scenario, the government will achieve its targets in renewable energy and in the reduction of the emissions of CO2. This will allow reaching a sustainable electricity sector.

Dyna, Aug 1, 2011

In this paper the power system voltage stability problem is analyzed with active power-voltage (P... more In this paper the power system voltage stability problem is analyzed with active power-voltage (PV) curves, as a voltage compensator is introduced. The PV curves' shape has been a subject of great concern, especially when voltage compensators are incorporated. Nevertheless, when such devices are taken into account, ordinarily the power electronic devices' commutation it is not considered in detail. This paper proposes a shunt connected voltage compensator model that gives careful consideration to commutation dynamics. Through load variations, simulations are carried out for building the PV curves. Additionally, the field over-current protection in generators is taken into account in order to evaluate its impact on the aforementioned curves. A single-phase equivalent shunt compensator, and the proposed model, is simulated in a small power system. Results are exhibited, which show particularities that arise due to the proposed model.

International Journal of Electrical Power & Energy Systems, 2016

This paper is aimed to propose a reliable method for estimating the voltage collapse proximity th... more This paper is aimed to propose a reliable method for estimating the voltage collapse proximity through a model obtained using statistical techniques. In the model building process a database is required, therefore the Voltage Collapse Proximity Index (VCPI) is used to obtain previous readings for different contingencies and loading conditions. This analytical proposal could be combined with existing equipment in the power system control centers for future on-line applications. The proposed method is applied to the IEEE 14-bus test system and the 190-bus Mexican equivalent. Results indicate that the proposed strategy is a reliable choice.

Smart Grid and Renewable Energy, 2011

Modeling of photovoltaic (PV) and wind farms (WF) stations to take into account these renewable e... more Modeling of photovoltaic (PV) and wind farms (WF) stations to take into account these renewable energies into the power flow formulation are summarized. A strategy based on multi objective optimization in order to allocate PV and WF power into electrical power system is proposed. It is assumed that there are a reduced number of choices to allocate the stations. The algorithm is applied to the 39-bus test power system. The results show that the proposed algorithm is capable of optimal placement of renewable units.

Información tecnológica, 2014

Este artículo propone una metodología para la coordinación y operación de grandes sistemas de pot... more Este artículo propone una metodología para la coordinación y operación de grandes sistemas de potencia de forma descentralizada, simplificando la optimización y reduciendo los tiempos de cómputo. La búsqueda óptima del voltaje de los generadores, cambiador de tomas, y compensación, se logra utilizando una técnica evolutiva, planteándola como un problema de optimización multiobjetivo. Se considera la descomposición tanto de la red como el problema de optimización y se valida con dos casos de prueba (39 y 190 nodos). Los resultados muestran una operación óptima global preservando la estabilidad de voltaje y la gestión de intercambios entre áreas, con mínima información operativa, simplicidad en los equivalentes y reducción en tiempos de cómputo. Los resultados son similares a los obtenidos mediante una estrategia de optimización centralizada.

DYNA, 2014

This paper presents a multi-objective teaching learning algorithm based on decomposition for solv... more This paper presents a multi-objective teaching learning algorithm based on decomposition for solving the optimal reactive power dispatch problem (ORPD). The effectiveness and performance of the proposed algorithm are compared with respect to a multi-objective evolutionary algorithm based on decomposition (MOEA/D) and the NSGA-II. A benchmark power system model is used to test the algorithms' performance. The results of the power losses reduction as well as the performance metrics indicate that the proposed algorithm is a reliable choice for solving the problem.

The 2013 International Joint Conference on Neural Networks (IJCNN), 2013

This paper presents an adaptive control strategy for wind energy conversion systems. The control ... more This paper presents an adaptive control strategy for wind energy conversion systems. The control scheme uses a B-spline artificial neural network for tuning controllers when the system is subjected to disturbances. Voltage-source converter is controlled in a synchronous orthogonal d-q frame by an adaptive PI controller. The B-spline neural network must be able to enhance the system performance through online updating parameters. Thus, the paper proposes the use of adaptive PI controllers to regulate the current, frequency, and DC link voltage. MatLab is employed for simulation studies to verify the performance of the proposed strategy.

Lecture Notes in Computer Science, 2009

This paper presents the Static Synchronous Compensator's (Stat-Com) voltage regulation by a B-Spl... more This paper presents the Static Synchronous Compensator's (Stat-Com) voltage regulation by a B-Spline neural network. The fact that the electric grid is a non-stationary system, with varying parameters and configurations, adaptive control schemes may be advisable. Thereby the control technique must guarantee its performance on the actual operating environment where the Stat-Com is embedded. An artificial neural network (ANN) is trained to foresee the device's behavior and to tune the corresponding controllers. Proportional-Integral (PI) and B-Spline controllers are assembled for the StatCom's control, where the tuning of parameters is based on the neural network model. Results of the lab prototype are exhibited under different conditions.

Electric Power Systems Research, 2015

This paper is concerned with voltage instability detection in power systems. The Impedance Matchi... more This paper is concerned with voltage instability detection in power systems. The Impedance Matching (IM) equations are formulated as sensitivities-based equations and practical issues about impedance matching are addressed. This research presents a direct relationship between IM and power injection sensitivities, and proposes the use of a Sensitivity Impedance Matching-(SIM) for detection of instability conditions. SIM may detect the Maximum Transfer Point (MTP) and the Saddle-Node Bifurcation (SNB-the maximum loadability point). Prediction capabilities of SIM based on anticipation parameters and reactive generation limitation in advance are presented. Approximated active, reactive, and also apparent margin indices are proposed. The paper introduces novel theoretical results for designing reliable Voltage Instability Detection (VID) schemes.

2006 38th North American Power Symposium, 2006

In this paper applications are presented employing the neural-based predictive control (NPC) for ... more In this paper applications are presented employing the neural-based predictive control (NPC) for controlling Flexible AC Transmission Systems (FACTS) devices with the purpose of regulating: bus voltage magnitudes through the use of a Static Compensator (STATCOM) and the active power flow on a transmission line where a Static Synchronous Series Compensator (SSSC) is embedded. Contrary to a Proportional-Integral (PI) conventional control with its trial-and error tuning, once trained a neural net able to predict the firing angle, simple calculations are required to achieve the wanted regulation. Thus, the NPC is a convenient tool to execute the power system adaptive control, with the possibility of carrying out such tasks considering non-linearities. The controller's design simplicity and its performance compared with the conventional PI controller are shown, especially those related with overshoots and control signals quality, impacting directly into the controlled variable response and having softer behavior than that of the PI control. The applicability of the proposition is studied by digital simulation.

Journal of Electromagnetic Analysis and Applications, 2010

The aim of this paper is to contribute to the dynamic modeling of multi-pulse voltage sourced con... more The aim of this paper is to contribute to the dynamic modeling of multi-pulse voltage sourced converter based static synchronous series compensator and static synchronous compensator. Details about the internal functioning and topology connections are given in order to understand the multi-pulse converter. Using the 24 and 48-pulse topologies switching functions models are presented. The models correctly represent commutations of semiconductor devices in multi-pulse converters, which consequently allows a precise representation of harmonic components. Additionally, time domain models that represent harmonic components are derived based on the switching functions models. Switching functions, as well as time domain models are carried out in the original abc power system coordinates. Effectiveness and precision of the models are validated against simulations performed in Matlab/Simulink ®. Additionally, in order to accomplish a more realistic comparison, a laboratory prototype set up is used to assess simulated waveforms.

IET Generation, Transmission & Distribution, 2007

Here the analysis on the inclusion of a pulse width modulated (PWM) ac link unified power flow co... more Here the analysis on the inclusion of a pulse width modulated (PWM) ac link unified power flow controller into a power flow program is discussed. Similarly, a PWM series compensator is connected to the power system to regulate the active power flow on the corresponding transmission line. Details of the Newton-Raphson's power flow algorithm are exhibited. Results of simulation are presented on a 39-buses power system.

IEEE Transactions on Power Delivery, 2010

Complete stability analyses, including voltage, small perturbation and transient stability studie... more Complete stability analyses, including voltage, small perturbation and transient stability studies, and the associated models and controls of a Series Vectorial Compensator (SVeC) are presented in this paper. A full comparative evaluation of this controller with respect to controllers used mainly for oscillation control in transmission corridors, namely, Thyristor-Controlled Series Capacitors (TCSC) and Series Static Synchronous Compensators (SSSC), is presented for the first time. The IEEE 14bus benchmark system and a 190-bus, 46-machine model of the Mexican grid are used for illustrative and comparison purposes. The results obtained show that the SVeC has better oscillation damping characteristics than the TCSC and SSSC, hence making these types of controllers a competitive alternative against existing series Flexible AC Transmission System (FACTS) controllers for dynamic series compensation of transmission lines, especially where space and cost are an issue.

Dyna, 2010

Disponible en: http://redalyc.uaemex.mx/src/inicio/ArtPdfRed.jsp?iCve=49615099021 ... Redalyc Sis... more Disponible en: http://redalyc.uaemex.mx/src/inicio/ArtPdfRed.jsp?iCve=49615099021 ... Redalyc Sistema de Información Científica Red de Revistas Científicas de América Latina, el Caribe, España y Portugal ... TAPIA, RUBEN; RIVAS, IVAN; RAMIREZ, JUAN M.; CORREA.G, ...