Fabio Andrés Pavas Martínez | Universidad Nacional de Colombia (original) (raw)
Issue 192 by Fabio Andrés Pavas Martínez
This paper proposes a methodology to model and analyze the security scheme required by a microgri... more This paper proposes a methodology to model and analyze the security scheme required by a microgrid that considers the participation of renewable energy sources. This security scheme is represented by an up and down spinning reserve, which allows to drive the system frequency to a steady state after the occurrence of events associated not only to forecast errors in the electricity demand (as traditional schemes do), but also to forecast errors in the power availability of the intermittent energy sources. The proposed methodology was implemented on a real microgrid that considers the interconnection of a photovoltaic generator. From this, it was concluded that the security scheme designed for the microgrid efficiently ensured the relation between generation and demand, at each study hour.
This paper presents a methodology to estimate the effects of heating and lifetime in Low Voltage ... more This paper presents a methodology to estimate the effects of heating and lifetime in Low Voltage conductors (LV) due to the presence of stationary power quality disturbances. Conductor overheating and cable insulation accelerated aging can be caused by temporary increases in the RMS values of the voltages and currents due to stationary disturbances. Waveform distortion, unbalance and phase displacements can be considered among the stationary disturbances. For disturbances with short duration, there are no significant reductions in the insulation lifetime, but disturbances acting for long time periods will cause cumulative and detrimental effects. Currently valid models for insulation aging are employed; the expected power quality disturbance levels are extracted from power quality databases. A discussion about the effects on insulation lifetime is presented.
A methodology that is based on epidemiological analysis to assess risk factors and harmonic disto... more A methodology that is based on epidemiological analysis to assess risk factors and harmonic distortion incidence rate in a distribution network is proposed in this paper. The methodology analyzes the current harmonics emission risk at the PCC due to the connection of disturbing loads. These loads are modeled, and multiple loads connection scenarios are simulated using Monte Carlo Algorithms. From the simulation results, potential risk factors for critical harmonics indicators are identified, leading to a classification of the scenarios into groups of exposed or unexposed to risk factors. Finally, the incidence rate of harmonics is calculated for each load connection scenario and the risk of critical harmonics scenarios due to the exposure to risk factors is estimated.
Papers by Fabio Andrés Pavas Martínez
2009 IEEE Bucharest PowerTech, 2009
Currently several methodologies exist to assess the Responsibilities Assignment Problem in Power ... more Currently several methodologies exist to assess the Responsibilities Assignment Problem in Power Quality. In this paper an experimental setup with two known disturbing electrically and mechanically coupled loads has been used to provide a reference disturbance setup for comparing these methodologies. The results and discussion extracted from this experiment is reported in this paper. The setup offered the possibility of adjusting the active power direction under several operative conditions and under two different feeding network configurations. Quantities defined in the standards IEEE 1459 and DIN 40110 are also employed to broaden the analysis and diagnostic possibilities.
Ingeniería e Investigación, 2015
Power transformer failures have a signiicant impact on electrical systems reliability, as they co... more Power transformer failures have a signiicant impact on electrical systems reliability, as they compromise the electricity delivery. Failures impact the operational cost of electric utilities as they endanger the accomplishment of power commitments. Power transformer failure rate can be modeled from its health condition, which is determined from different condition parameters. This paper is aimed to compare different maintenance schemes that allow the asset to be available the longest possible time. The power transformer operation is represented considering actual electric load proiles and temperature. Electrical and thermal transformer parameters are taken from manufacturer tests and technical standards. An electrical-thermal model is employed to estimate the life span reduction and temperature changes. From life span and loading, the health condition is determined, so as the effects of different maintenance schemes. The failure rates are calculated for unmaintained conditions and different maintained schemes, allowing to determine their effects on transformer reliability. Optimal maintenance schemes are determined and the expected beneits in failure rate reduction, asset reliability and life span extension are presented. As a result, it was found that certain time-based maintenance schemes provide better transformer reliability performance in comparison to condition based schemes, allowing to reduce the interruptions and extending the life of the transformer.
2015 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA), 2015
This paper shows the results obtained from the simulated study case about the impact of harmonics... more This paper shows the results obtained from the simulated study case about the impact of harmonics on a distribution transformer useful life. These results depend on the supplied energy level (power variation along the time) under three different demand profiles with the same harmonics level. It will be presented that the transformer overload affects the transformer useful life subjected to the presence of peaks and valleys in the weekly demand profile, providing period times to the transformer for the temperature increase (peaks) or decrease (valleys). These temperature variations will affect directly the transformer loss of life and will show that not only the harmonic presence on the transformer operation will accelerate its aging, but also other conditions allow a slow aging and even a useful life beyond the rated expectation. The possible effects of more complex disturbing scenarios, like unbalanced currents and high reactive power feeding, are presented as discussion.
The research groups ranking is a periodic activity aimed at assessing the performance of research... more The research groups ranking is a periodic activity aimed
at assessing the performance of researchers and research
groups, so as to promote the continuous improvement,
academic exchange and visibility of the national scientific
production. In previous editorial notes of Ingeniería e
Investigación (Narváez, 2014; Pavas, 2015), a revision of
the research groups ranking in the Universidad Nacional
de Colombia – UN was presented for the last two years.
Upon the implementation of a new model for classifying national journals, different indicators fo... more Upon the implementation of a new model for classifying
national journals, different indicators for measuring
journal impact are still a topic of discussion. In the
most recent editorial note of Ingeniería e Investigación
(Pavas, 2015), the classification of colombian journals
was presented with respect to the most recognized
international indexes.
Nowadays electricity systems are moving rapidly towards smart grids for improving electric power ... more Nowadays electricity systems are moving rapidly towards smart grids for improving electric power efficiency, voltage
regulation, reliability and quality. Latin America’s electricity systems are not indifferent to such tendency; many ef-
forts have been made during the last years, but many difficulties still remain unsolved. Electric power quality issues
are directly related to all expected smart grid improvements; the necessary technical developments, the research and
experimental experience orientated towards resolving existing problems are thus highly pertinent.
—Currently the impact of high efficient lighting devices such as compact fluorescent lamps (CFL) ... more —Currently the impact of high efficient lighting devices such as compact fluorescent lamps (CFL) and light emitting diodes (LED) is an important concern for the electrotechnical community. This paper makes a contribution towards determining the impact of these devices on electric grid power quality and efficiency, proposed by means of applying FBD-power theory to the currents absorbed by CFLs and LEDs. An analysis of the waveform distortion regarding IEEE standard 519 and efficiency detriment quantification are presented. Resumen— Actualmente el impacto de los dispositivos de iluminación eficiente tales como Lámparas Compactas Fluorescentes-CFL y Diodos Emisores de Luz-LED representa un interés importante para la comunidad electrotécnica. En este artículo se propone una contribución a la determinación del impacto de tales dispositivos a la calidad de potencia y la eficiencia de una red eléctrica, por medio de la aplicación de la Teoría de Potencia FBD a las corrientes absorbidas por CFL y LED. Se presentan un análisis de la distorsión de la forma de onda con respecto a la norma IEEE 519 y una cuantificación de los detrimentos en la eficiencia. Palabras clave— Teoría de potencia FBD, CFL, LED, descomposición ortogonal, eficiencia, calidad de potencia.
Current and voltage harmonic levels in LV grids depend not only on the harmonic emission of non-l... more Current and voltage harmonic levels in LV grids depend not only on the harmonic emission of non-linear loads, but also on the characteristics of the grid and the voltage distortion of the upstream grid. Based on several measurements, it was found that Colombia and Germany have considerable differences in the current harmonic emission of electronic devices and voltage distortion in the LV-grids. These differences are the result of different regulation methodologies and the characteristics of the grid. Detail measurement campaigns are needed in both countries in order to verify the voltage and current harmonic levels, and to analyze the network efficiency and hosting capacity in terms of harmonics. RESUMEN Los niveles de distorsión armónica en las redes de baja tensión no dependen únicamente de las cargas no lineales conectadas al sistema, sino también de las características de la red y la distorsión de tensión proveniente de la red de media tensión. Considerables diferencias en la emisión de armónicos de equipos electrónicos y los niveles de distorsión de tensión en las redes de baja tensión en Colombia y Alemania fueron identificados a partir de varias mediciones. Estas diferencias se deben principalmente a la normatividad y las características de las redes en cada país. Se recomienda realizar campañas de medición en ambos países para verificar los niveles de distorsión y analizar la eficiencia y la capacidad de la red en términos de armónicos. Palabras clave: Emisión de armónicos, distorsión armónica, efecto de cancelación, calidad de potencia.
In previous editorial notes from Ingeniería e Investigación, some of the impacts that the new mea... more In previous editorial notes from Ingeniería e Investigación,
some of the impacts that the new measurement model of
Research Groups at the Universidad Nacional de Colom-
bia has had were reviewed (Narvaez, 2014), (Pavas, 2015).
This paper proposes k-means clustering algorithm to identify voltage sags patterns and group faul... more This paper proposes k-means clustering algorithm to identify voltage sags patterns and group fault zones with similar impact in high and medium voltage electric. The proposed methodology comprises three stages. First, network modeling and faults simulation were performed in order to get information about voltage sags caused by faults in the transmission system. Voltage sags patterns were identified at the second stage by means of a k-means clustering algorithm, allowing the determination of fault zones. Using the power quality measurements data base of the major electricity utility of Bogotá, voltage sags were classified according to the previously determined voltage sags patterns. At the third stage of the methodology a comparison between simulated and measured sags is performed, allowing the identification of sags caused by faults. Resumen-En este artículo se propone el uso del algoritmo K-means para identificar patrones de hundimientos en tensión y agrupar zonas de falla con impacto similar en redes de alta y media tensión. La metodología propuesta comprende tres etapas. Primero, se realiza un modelo de la red de transmisión y distribución y se simula un barrido de todo tipo de fallas, obteniendo información sobre los hundimientos en tensión. En segundo lugar, se identifican patrones de hundimientos en tensión usando el algoritmo k-means y se determinan diferentes zonas de falla para cada uno de los patrones. Finalmente, se usan los patrones encontrados para clasificar información real de hundimientos en tensión registrados en Bogotá y se establecen las zonas de falla para grupos de hundimientos en tensión. Palabras Clave: Clasificación de hundimientos en tensión, patrones de hundimientos en tensión, algoritmo k-means.
The International Symposium on Power Quality was held for the irst time in October 2001 and took ... more The International Symposium on Power Quality was held
for the irst time in October 2001 and took place in Bogotá.
It was planned in order to provide and academic and
professional space to discuss and exchange the experience
on topics related to the quality of electricity service. SICEL
has evolved from the main causes of faults and electric
system outages, to the most recent developments for
improving systems reliability and possibilities to develop
new businesses and markets based on power quality.
Power transformer failures have a signiicant impact on electrical systems reliability, as they co... more Power transformer failures have a signiicant impact on electrical systems reliability, as they compromise the electricity delivery. Failures impact the operational cost of electric utilities as they endanger the accomplishment of power commitments. Power transformer failure rate can be modeled from its health condition, which is determined from different condition parameters. This paper is aimed to compare different maintenance schemes that allow the asset to be available the longest possible time. The power transformer operation is represented considering actual electric load proiles and temperature. Electrical and thermal transformer parameters are taken from manufacturer tests and technical standards. An electrical-thermal model is employed to estimate the life span reduction and temperature changes. From life span and loading, the health condition is determined, so as the effects of different maintenance schemes. The failure rates are calculated for unmaintained conditions and different maintained schemes, allowing to determine their effects on transformer reliability. Optimal maintenance schemes are determined and the expected beneits in failure rate reduction, asset reliability and life span extension are presented. As a result, it was found that certain time-based maintenance schemes provide better transformer reliability performance in comparison to condition based schemes, allowing to reduce the interruptions and extending the life of the transformer. RESUMEN Las fallas en los transformadores de potencia tienen un impacto signiicativo sobre la coniabilidad de los sistemas eléctricos, debido a que comprometen la prestación del servicio de energía. Las fallas impactan los costos operacionales de la energía debido a que ponen en riesgo el cumplimiento de los contratos de energía. La tasa de falla en los transformadores de potencia puede modelarse a partir de su condición de salud, la cual es determinada a partir de diferentes parámetros de condición. Este artículo apunta a comparar diferentes esquemas de mantenimiento que permitan tener el activo disponible el mayor tiempo posible. La operación del transformador de potencia es representada considerando periles reales de temperatura y carga eléctrica. Los parámetros eléctricos y térmicos del transformador son tomados de pruebas de fabricantes y estándares técnicos. Un modelo eléctrico-térmico es empleado para estimar la reducción de vida útil y los cambios de temperatura. A partir de la vida útil y la carga se determina la condición de salud, así como el efecto de diferentes esquemas de mantenimiento. Se calculan las tasas de falla para condiciones sin mantenimiento y para diferentes esquemas de mantenimiento, permitiendo determinar los efectos en la coniabilidad del transformador. De los esquemas de mantenimiento se presentan los beneicios esperados en la reducción de la tasa de fallas, coniabilidad del activo y extensión de la vida útil. Como resultado, se encontró que ciertos esquemas de mantenimiento basados en el tiempo proveen un mejor desempeño de la coniabilidad del transformador que permitiendo reducir las interrupciones y extendiendo la vida útil del transformador. Palabras clave: Transformador de potencia, tasa de fallas, mantenimiento, índices de salud, mejoramiento de la coniabilidad, gestión de activos.
Visibility and impact are the current measures for any scientific publication. Journals are not e... more Visibility and impact are the current measures for any scientific
publication. Journals are not exceptions. Colombia has positioned
several publications within the international standards. In this editorial
note I would like to present a short view about the Colombian
engineering journals.
This paper proposes a methodology to model and analyze the security scheme required by a microgri... more This paper proposes a methodology to model and analyze the security scheme required by a microgrid that considers the participation of renewable energy sources. This security scheme is represented by an up and down spinning reserve, which allows to drive the system frequency to a steady state after the occurrence of events associated not only to forecast errors in the electricity demand (as traditional schemes do), but also to forecast errors in the power availability of the intermittent energy sources. The proposed methodology was implemented on a real microgrid that considers the interconnection of a photovoltaic generator. From this, it was concluded that the security scheme designed for the microgrid efficiently ensured the relation between generation and demand, at each study hour.
This paper presents a methodology to estimate the effects of heating and lifetime in Low Voltage ... more This paper presents a methodology to estimate the effects of heating and lifetime in Low Voltage conductors (LV) due to the presence of stationary power quality disturbances. Conductor overheating and cable insulation accelerated aging can be caused by temporary increases in the RMS values of the voltages and currents due to stationary disturbances. Waveform distortion, unbalance and phase displacements can be considered among the stationary disturbances. For disturbances with short duration, there are no significant reductions in the insulation lifetime, but disturbances acting for long time periods will cause cumulative and detrimental effects. Currently valid models for insulation aging are employed; the expected power quality disturbance levels are extracted from power quality databases. A discussion about the effects on insulation lifetime is presented.
A methodology that is based on epidemiological analysis to assess risk factors and harmonic disto... more A methodology that is based on epidemiological analysis to assess risk factors and harmonic distortion incidence rate in a distribution network is proposed in this paper. The methodology analyzes the current harmonics emission risk at the PCC due to the connection of disturbing loads. These loads are modeled, and multiple loads connection scenarios are simulated using Monte Carlo Algorithms. From the simulation results, potential risk factors for critical harmonics indicators are identified, leading to a classification of the scenarios into groups of exposed or unexposed to risk factors. Finally, the incidence rate of harmonics is calculated for each load connection scenario and the risk of critical harmonics scenarios due to the exposure to risk factors is estimated.
2009 IEEE Bucharest PowerTech, 2009
Currently several methodologies exist to assess the Responsibilities Assignment Problem in Power ... more Currently several methodologies exist to assess the Responsibilities Assignment Problem in Power Quality. In this paper an experimental setup with two known disturbing electrically and mechanically coupled loads has been used to provide a reference disturbance setup for comparing these methodologies. The results and discussion extracted from this experiment is reported in this paper. The setup offered the possibility of adjusting the active power direction under several operative conditions and under two different feeding network configurations. Quantities defined in the standards IEEE 1459 and DIN 40110 are also employed to broaden the analysis and diagnostic possibilities.
Ingeniería e Investigación, 2015
Power transformer failures have a signiicant impact on electrical systems reliability, as they co... more Power transformer failures have a signiicant impact on electrical systems reliability, as they compromise the electricity delivery. Failures impact the operational cost of electric utilities as they endanger the accomplishment of power commitments. Power transformer failure rate can be modeled from its health condition, which is determined from different condition parameters. This paper is aimed to compare different maintenance schemes that allow the asset to be available the longest possible time. The power transformer operation is represented considering actual electric load proiles and temperature. Electrical and thermal transformer parameters are taken from manufacturer tests and technical standards. An electrical-thermal model is employed to estimate the life span reduction and temperature changes. From life span and loading, the health condition is determined, so as the effects of different maintenance schemes. The failure rates are calculated for unmaintained conditions and different maintained schemes, allowing to determine their effects on transformer reliability. Optimal maintenance schemes are determined and the expected beneits in failure rate reduction, asset reliability and life span extension are presented. As a result, it was found that certain time-based maintenance schemes provide better transformer reliability performance in comparison to condition based schemes, allowing to reduce the interruptions and extending the life of the transformer.
2015 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA), 2015
This paper shows the results obtained from the simulated study case about the impact of harmonics... more This paper shows the results obtained from the simulated study case about the impact of harmonics on a distribution transformer useful life. These results depend on the supplied energy level (power variation along the time) under three different demand profiles with the same harmonics level. It will be presented that the transformer overload affects the transformer useful life subjected to the presence of peaks and valleys in the weekly demand profile, providing period times to the transformer for the temperature increase (peaks) or decrease (valleys). These temperature variations will affect directly the transformer loss of life and will show that not only the harmonic presence on the transformer operation will accelerate its aging, but also other conditions allow a slow aging and even a useful life beyond the rated expectation. The possible effects of more complex disturbing scenarios, like unbalanced currents and high reactive power feeding, are presented as discussion.
The research groups ranking is a periodic activity aimed at assessing the performance of research... more The research groups ranking is a periodic activity aimed
at assessing the performance of researchers and research
groups, so as to promote the continuous improvement,
academic exchange and visibility of the national scientific
production. In previous editorial notes of Ingeniería e
Investigación (Narváez, 2014; Pavas, 2015), a revision of
the research groups ranking in the Universidad Nacional
de Colombia – UN was presented for the last two years.
Upon the implementation of a new model for classifying national journals, different indicators fo... more Upon the implementation of a new model for classifying
national journals, different indicators for measuring
journal impact are still a topic of discussion. In the
most recent editorial note of Ingeniería e Investigación
(Pavas, 2015), the classification of colombian journals
was presented with respect to the most recognized
international indexes.
Nowadays electricity systems are moving rapidly towards smart grids for improving electric power ... more Nowadays electricity systems are moving rapidly towards smart grids for improving electric power efficiency, voltage
regulation, reliability and quality. Latin America’s electricity systems are not indifferent to such tendency; many ef-
forts have been made during the last years, but many difficulties still remain unsolved. Electric power quality issues
are directly related to all expected smart grid improvements; the necessary technical developments, the research and
experimental experience orientated towards resolving existing problems are thus highly pertinent.
—Currently the impact of high efficient lighting devices such as compact fluorescent lamps (CFL) ... more —Currently the impact of high efficient lighting devices such as compact fluorescent lamps (CFL) and light emitting diodes (LED) is an important concern for the electrotechnical community. This paper makes a contribution towards determining the impact of these devices on electric grid power quality and efficiency, proposed by means of applying FBD-power theory to the currents absorbed by CFLs and LEDs. An analysis of the waveform distortion regarding IEEE standard 519 and efficiency detriment quantification are presented. Resumen— Actualmente el impacto de los dispositivos de iluminación eficiente tales como Lámparas Compactas Fluorescentes-CFL y Diodos Emisores de Luz-LED representa un interés importante para la comunidad electrotécnica. En este artículo se propone una contribución a la determinación del impacto de tales dispositivos a la calidad de potencia y la eficiencia de una red eléctrica, por medio de la aplicación de la Teoría de Potencia FBD a las corrientes absorbidas por CFL y LED. Se presentan un análisis de la distorsión de la forma de onda con respecto a la norma IEEE 519 y una cuantificación de los detrimentos en la eficiencia. Palabras clave— Teoría de potencia FBD, CFL, LED, descomposición ortogonal, eficiencia, calidad de potencia.
Current and voltage harmonic levels in LV grids depend not only on the harmonic emission of non-l... more Current and voltage harmonic levels in LV grids depend not only on the harmonic emission of non-linear loads, but also on the characteristics of the grid and the voltage distortion of the upstream grid. Based on several measurements, it was found that Colombia and Germany have considerable differences in the current harmonic emission of electronic devices and voltage distortion in the LV-grids. These differences are the result of different regulation methodologies and the characteristics of the grid. Detail measurement campaigns are needed in both countries in order to verify the voltage and current harmonic levels, and to analyze the network efficiency and hosting capacity in terms of harmonics. RESUMEN Los niveles de distorsión armónica en las redes de baja tensión no dependen únicamente de las cargas no lineales conectadas al sistema, sino también de las características de la red y la distorsión de tensión proveniente de la red de media tensión. Considerables diferencias en la emisión de armónicos de equipos electrónicos y los niveles de distorsión de tensión en las redes de baja tensión en Colombia y Alemania fueron identificados a partir de varias mediciones. Estas diferencias se deben principalmente a la normatividad y las características de las redes en cada país. Se recomienda realizar campañas de medición en ambos países para verificar los niveles de distorsión y analizar la eficiencia y la capacidad de la red en términos de armónicos. Palabras clave: Emisión de armónicos, distorsión armónica, efecto de cancelación, calidad de potencia.
In previous editorial notes from Ingeniería e Investigación, some of the impacts that the new mea... more In previous editorial notes from Ingeniería e Investigación,
some of the impacts that the new measurement model of
Research Groups at the Universidad Nacional de Colom-
bia has had were reviewed (Narvaez, 2014), (Pavas, 2015).
This paper proposes k-means clustering algorithm to identify voltage sags patterns and group faul... more This paper proposes k-means clustering algorithm to identify voltage sags patterns and group fault zones with similar impact in high and medium voltage electric. The proposed methodology comprises three stages. First, network modeling and faults simulation were performed in order to get information about voltage sags caused by faults in the transmission system. Voltage sags patterns were identified at the second stage by means of a k-means clustering algorithm, allowing the determination of fault zones. Using the power quality measurements data base of the major electricity utility of Bogotá, voltage sags were classified according to the previously determined voltage sags patterns. At the third stage of the methodology a comparison between simulated and measured sags is performed, allowing the identification of sags caused by faults. Resumen-En este artículo se propone el uso del algoritmo K-means para identificar patrones de hundimientos en tensión y agrupar zonas de falla con impacto similar en redes de alta y media tensión. La metodología propuesta comprende tres etapas. Primero, se realiza un modelo de la red de transmisión y distribución y se simula un barrido de todo tipo de fallas, obteniendo información sobre los hundimientos en tensión. En segundo lugar, se identifican patrones de hundimientos en tensión usando el algoritmo k-means y se determinan diferentes zonas de falla para cada uno de los patrones. Finalmente, se usan los patrones encontrados para clasificar información real de hundimientos en tensión registrados en Bogotá y se establecen las zonas de falla para grupos de hundimientos en tensión. Palabras Clave: Clasificación de hundimientos en tensión, patrones de hundimientos en tensión, algoritmo k-means.
The International Symposium on Power Quality was held for the irst time in October 2001 and took ... more The International Symposium on Power Quality was held
for the irst time in October 2001 and took place in Bogotá.
It was planned in order to provide and academic and
professional space to discuss and exchange the experience
on topics related to the quality of electricity service. SICEL
has evolved from the main causes of faults and electric
system outages, to the most recent developments for
improving systems reliability and possibilities to develop
new businesses and markets based on power quality.
Power transformer failures have a signiicant impact on electrical systems reliability, as they co... more Power transformer failures have a signiicant impact on electrical systems reliability, as they compromise the electricity delivery. Failures impact the operational cost of electric utilities as they endanger the accomplishment of power commitments. Power transformer failure rate can be modeled from its health condition, which is determined from different condition parameters. This paper is aimed to compare different maintenance schemes that allow the asset to be available the longest possible time. The power transformer operation is represented considering actual electric load proiles and temperature. Electrical and thermal transformer parameters are taken from manufacturer tests and technical standards. An electrical-thermal model is employed to estimate the life span reduction and temperature changes. From life span and loading, the health condition is determined, so as the effects of different maintenance schemes. The failure rates are calculated for unmaintained conditions and different maintained schemes, allowing to determine their effects on transformer reliability. Optimal maintenance schemes are determined and the expected beneits in failure rate reduction, asset reliability and life span extension are presented. As a result, it was found that certain time-based maintenance schemes provide better transformer reliability performance in comparison to condition based schemes, allowing to reduce the interruptions and extending the life of the transformer. RESUMEN Las fallas en los transformadores de potencia tienen un impacto signiicativo sobre la coniabilidad de los sistemas eléctricos, debido a que comprometen la prestación del servicio de energía. Las fallas impactan los costos operacionales de la energía debido a que ponen en riesgo el cumplimiento de los contratos de energía. La tasa de falla en los transformadores de potencia puede modelarse a partir de su condición de salud, la cual es determinada a partir de diferentes parámetros de condición. Este artículo apunta a comparar diferentes esquemas de mantenimiento que permitan tener el activo disponible el mayor tiempo posible. La operación del transformador de potencia es representada considerando periles reales de temperatura y carga eléctrica. Los parámetros eléctricos y térmicos del transformador son tomados de pruebas de fabricantes y estándares técnicos. Un modelo eléctrico-térmico es empleado para estimar la reducción de vida útil y los cambios de temperatura. A partir de la vida útil y la carga se determina la condición de salud, así como el efecto de diferentes esquemas de mantenimiento. Se calculan las tasas de falla para condiciones sin mantenimiento y para diferentes esquemas de mantenimiento, permitiendo determinar los efectos en la coniabilidad del transformador. De los esquemas de mantenimiento se presentan los beneicios esperados en la reducción de la tasa de fallas, coniabilidad del activo y extensión de la vida útil. Como resultado, se encontró que ciertos esquemas de mantenimiento basados en el tiempo proveen un mejor desempeño de la coniabilidad del transformador que permitiendo reducir las interrupciones y extendiendo la vida útil del transformador. Palabras clave: Transformador de potencia, tasa de fallas, mantenimiento, índices de salud, mejoramiento de la coniabilidad, gestión de activos.
Visibility and impact are the current measures for any scientific publication. Journals are not e... more Visibility and impact are the current measures for any scientific
publication. Journals are not exceptions. Colombia has positioned
several publications within the international standards. In this editorial
note I would like to present a short view about the Colombian
engineering journals.