Mario Manana - Academia.edu (original) (raw)

Papers by Mario Manana

Research paper thumbnail of Advanced Maintenance of Distribution Assets Through the Application of Predictive Techniques Using GE'S APM System: Real Case in a Spanish DSO

Lecture notes in mechanical engineering, 2023

Research paper thumbnail of Increase of capacity in electric arc-furnace steel mill factories by means of a demand-side management strategy and ampacity techniques

International Journal of Electrical Power & Energy Systems, 2021

An electric arc-furnace is a complex industry which demands high levels of electrical energy in o... more An electric arc-furnace is a complex industry which demands high levels of electrical energy in order to heat iron materials and other additives needed for the production of cast iron and/or steelmaking. The cost of the electrical energy demanded by the factory during the production can be greater than 20% of the overall cost. This kind of arc-furnace allows the production of steel with levels of scrap metal feedstock up to 100%. From an electrical point of view, the factory size in terms of its maximum apparent power demanded from the grid is designed to make use of the static capacity of the transmission line that supplies the energy. In that case, it is not possible to increase the power of the factory above the static rating by adding new facilites without installing new transmission infrastructures. This paper presents a methodology that allows an increase in net power of an arc-furnace factory without installing new transmission lines. The solution is based on a mix strategy that combines Demand-Side Management (DSM) methodologies and the use of ampacity techniques according IEEE 738 and CIGRE TB601. The application of DSM methodologies provides an improvement in the sustainability of not only the industrial customer but also in the overall grid. As a

Research paper thumbnail of Power Quality – Monitoring, Analysis and Enhancement

Research paper thumbnail of Criterios Para Una Facturación De La Energía Eléctrica Más Equitativa

Research paper thumbnail of BIodIVersIty Indexes APPlIed to the AnAlysIs oF suPPly securIty In Power systems

Interciencia, 2011

In the last decade the growth in electricity demand in Spain was~ 4.5% annually; capacity and ene... more In the last decade the growth in electricity demand in Spain was~ 4.5% annually; capacity and energy demand forecasts estimate that this growth will continue, but at a lower rate (MITC, 2006). Table I shows the power generation mix that has almost entirely covered the ...

Research paper thumbnail of Electrotecnia Para Ingenieros De Telecomunicación

Acceso de usuarios registrados. Acceso de usuarios registrados Usuario Contraseña. ...

Research paper thumbnail of Utilización De Las Pruebas Objetivas Para El Aprendizaje/Evaluación. Aplicación a La Ingeniería Eléctrica

… Educativa en las …, 2007

Acceso de usuarios registrados. Acceso de usuarios registrados Usuario Contraseña. ...

Research paper thumbnail of Techniques to Locate the Origin of Power Quality Disturbances in a Power System: A Review

Sustainability

The complexity in the power system topology, together with the new paradigm in generation and dem... more The complexity in the power system topology, together with the new paradigm in generation and demand, make achieving an adequate level of supply quality a complicated goal for distribution companies. The electrical system power quality is subject to different regulations. On one hand, EN-50160 establishes the characteristics of the voltage supplied by public electricity networks, therefore affecting distribution companies. On the other hand, the EN-61000 series of standards regulates the electromagnetic compatibility of devices connected to the network, therefore affecting the loads. Power companies and device manufacturers are both responsible and affected in the issue of quality of supply. Despite the regulations, there are certain aspects of the supply quality that are not solved. One of the most important is the location of the disturbance’s origin. This paper presents a review of the main techniques to locate the disturbance’s origin in the electric network through two approach...

Research paper thumbnail of Ferroresonance Detection in Voltage Transformers Through Vibration Monitoring

Applied Condition Monitoring, 2019

Ferroresonance is a very studied phenomenon by the distribution electrical companies since it can... more Ferroresonance is a very studied phenomenon by the distribution electrical companies since it can cause damage to transformers and other line elements. This problem is generated by the association in series or in parallel of capacities (overhead and underground power lines) and saturable inductances (voltage transformers). During the ferroresonance, the Voltage Transformer (VT) becomes saturated and the magnetic field varies in a high way; all this produces that the ferromagnetic material dimensions of the transformer change due to the phenomenon of magnetostriction. Thus, magnetostriction generates a vibration on the transformer. The main effects produced by ferroresonance are as follow: core saturation, voltage and current distortion, overvoltages and overcurrents, temperature increase, vibration and noise. The aim of this paper is to detect the ferroresonance by analyzing the vibration on the VT.

Research paper thumbnail of Ferroresonance Mitigation Device in Voltage Transformers with a Flyback based Resistor Emulator

2018 IEEE 19th Workshop on Control and Modeling for Power Electronics (COMPEL), 2018

A widely configurable and scalable resistor emulator actively mitigates the ferroresonance phenom... more A widely configurable and scalable resistor emulator actively mitigates the ferroresonance phenomenon. This paper proposes a new variety of mitigation equipment based on power electronic converters operated as resistor emulators. The presence of a ferroresonance activates a flyback converter operating in the critical conduction mode (CrCM) with no specific output voltage control. The severity of the resonance configures the emulated resistance value. Results show a fast and effective response of the proposed device in comparison with the state-of-the-art solutions

Research paper thumbnail of Determination of Transformer Oil Contamination from the OLTC Gases in the Power Transformers of a Distribution System Operator

Applied Sciences, 2020

Power transformers are considered to be the most important assets in power substations. Thus, the... more Power transformers are considered to be the most important assets in power substations. Thus, their maintenance is important to ensure the reliability of the power transmission and distribution system. One of the most commonly used methods for managing the maintenance and establishing the health status of power transformers is dissolved gas analysis (DGA). The presence of acetylene in the DGA results may indicate arcing or high-temperature thermal faults in the transformer. In old transformers with an on-load tap-changer (OLTC), oil or gases can be filtered from the OLTC compartment to the transformer’s main tank. This paper presents a method for determining the transformer oil contamination from the OLTC gases in a group of power transformers for a distribution system operator (DSO) based on the application of the guides and the knowledge of experts. As a result, twenty-six out of the 175 transformers studied are defined as contaminated from the OLTC gases. In addition, this paper ...

Research paper thumbnail of BIodIVers Ity I ndexes APP lIed to the A nAlys Is o F su PPly secur Ity I n Power systems

SUMMARY The evolution of the vulnerability of the Spanish power generation system with respect to... more SUMMARY The evolution of the vulnerability of the Spanish power generation system with respect to the primary energy resources has been assessed by three new indexes developed from biodiversity analysis. The first of these indexes measures, in percentage, the uniformity of the primary energy resources in the system. The second one quantifies the diversity by means of the equivalent number of primary energy resources that are present in similar proportions in the system. The third one allows the calculation of the diversity reduction in the system with the non-evenness of these primary energy resources. They have been applied to the energy results of a stochastic linear model, developed with the software GAMS, in order to demonstrate their usefulness. In this model several generation technologies have been considered (nuclear, clean coal technologies, etc), and also several scenarios of fossil fuel costs. The number of primary energy resources that have to be used depends on the degr...

Research paper thumbnail of Systems with Large-Scale Wind Energy Generation

This paper is devoted to the development of a methodology suitable to be used to determine the im... more This paper is devoted to the development of a methodology suitable to be used to determine the impact of of wind farms in distribution networks that are also supplied with other classical generation facilities based on thermal and hydraulic energy. The methodology is based on an automated nalysis varies the level of the electric generation f r both the and thermal generators by using PSS, Phyton user can define multiple scenarios considering wind, thermal and hydraulic generators o the line capacity can be computed and compared in order to know where the system located and which situations occur. All the results computed can be analysed in a single or compared way by using tables and plots and con sidering the static rate of the distribution lines. The developed system can also be applied to the computation of the sensitivity of the power flow to the variation of the parameters that define the power system.

Research paper thumbnail of A Methodology for the Calculation of Typical Gas Concentration Values and Sampling Intervals in the Power Transformers of a Distribution System Operator

Energies, 2020

Predictive maintenance strategies in power transformers aim to assess the risk through the calcul... more Predictive maintenance strategies in power transformers aim to assess the risk through the calculation and monitoring of the health index of the power transformers. The parameter most used in predictive maintenance and to calculate the health index of power transformers is the dissolved gas analysis (DGA). The current tendency is the use of online DGA monitoring equipment while continuing to perform analyses in the laboratory. Although the DGA is well known, there is a lack of published experimental data beyond that in the guides. This study used the nearest-rank method for obtaining the typical gas concentration values and the typical rates of gas increase from a transformer population to establish the optimal sampling interval and alarm thresholds of the continuous monitoring devices for each power transformer. The percentiles calculated by the nearest-rank method were within the ranges of the percentiles obtained using the R software, so this simple method was validated for this ...

Research paper thumbnail of Toward Energy Savings in Campus Buildings under a Life Cycle Thinking Approach

Applied Sciences, 2020

Recent studies have identified that buildings all over the world are great contributors to energy... more Recent studies have identified that buildings all over the world are great contributors to energy consumption and greenhouse gas emissions. The relationship between the building industry and environmental pollution is continuously discussed. The building industry includes many phases: extraction of raw materials, manufacturing, construction, use, and demolition. Each phase consumes a large amount of energy, and subsequent emissions are released. The life cycle energy assessment (LCEA) is a simplified version of the life cycle assessment (LCA) that focuses only on the evaluation of energy inputs for different phases of the life cycle. Operational energy is the energy required for day-to-day operation processes of buildings, such as heating, cooling and ventilation systems, lighting, as well as appliances. This use phase accounts for the largest portion of energy consumption of the life cycle of conventional buildings. In addition, energy performance certification of buildings is an o...

Research paper thumbnail of Soluciones Anti-Isla en Baja y Media Tensión

DYNA INGENIERIA E INDUSTRIA, 2020

Research paper thumbnail of Stream Data Cleaning for Dynamic Line Rating Application

Energies, 2018

The maximum current that an overhead transmission line can continuously carry depends on external... more The maximum current that an overhead transmission line can continuously carry depends on external weather conditions, most commonly obtained from real-time streaming weather sensors. The accuracy of the sensor data is very important in order to avoid problems such as overheating. Furthermore, faulty sensor readings may cause operators to limit or even stop the energy production from renewable sources in radial networks. This paper presents a method for detecting and replacing sequences of consecutive faulty data originating from streaming weather sensors. The method is based on a combination of (a) a set of constraints obtained from derivatives in consecutive data, and (b) association rules that are automatically generated from historical data. In smart grids, a large amount of historical data from different weather stations are available but rarely used. In this work, we show that mining and analyzing this historical data provides valuable information that can be used for detecting...

Research paper thumbnail of Robust Optimization of Energy Hubs Operation Based on Extended Affine Arithmetic

Energies, 2019

Traditional energy systems were planned and operated independently, but the diffusion of distribu... more Traditional energy systems were planned and operated independently, but the diffusion of distributed and renewable energy systems led to the development of new modeling concepts, such as the energy hub. The energy hub is an integrated paradigm, based on the challenging idea of multi-carrier energy systems, in which multiple inputs are conditioned, converted and stored in order to satisfy different types of energy demand. To solve the energy hub optimal scheduling problem, uncertainty sources, such as renewable energy production, price volatility and load demand, must be properly considered. This paper proposes a novel methodology, based on extended Affine Arithmetic, which enables the solving of the optimal scheduling problem in the presence of multiple and heterogeneous uncertainty sources. Realistic case studies are presented and discussed in order to show the effectiveness of the proposed methodology.

Research paper thumbnail of Problems Derived from the Simultaneous Utilisation of Different Flickermeters in Large Electric Networks

Renewable Energy and Power Quality Journal, 2003

Power Quality assessment in distribution networks requires distributed measurements in order to v... more Power Quality assessment in distribution networks requires distributed measurements in order to verify the PQ state of the art. This process cannot simply be considered as an extension of a measurement at a given point because several variables need to be considered: number of PQM; election of optimal measurement location; synchronisation of instrumentation and management of captured data. This work focuses on the problems related with the simultaneous utilisation of different flickermeters in large electric networks. From a classical instrumentation point of view, several flickermeters from different customers are tested in the laboratory in order to determine the differences in the accuracy of the results. Both Pst and Plt are statistical parameters calculated using a large number of samples of the instantaneous flicker level I FL. The number of captured samples can vary from one instrument to another, so different flickermeters provide different values.

Research paper thumbnail of Influence on Power Quality Measurement of the Simultaneous Presence of Different Disturbances

Renewable Energy and Power Quality Journal, 2003

Power Quality measurements involve not only problems related with the real use of recorders but a... more Power Quality measurements involve not only problems related with the real use of recorders but also theoretical questions connected with functional and design aspects of the instrumentation. In addition, there are a rising number of standards covering topics from design to data analysis, so final users usually assume that they do not have to pay special attention to PQ instrumentation functionality when the device is designed according to approved standards. However, it is not unusual to find different disturbances at the same point and in the same time and standards do not say anything about their mutual influence on PQ index. The main aim of this research work is to show the influence that having different disturbances (flicker and sags) simultaneously has on the final results provided by the instrumentation for each individual disturbance. The paper proposes a test system and a methodology. The results of various tests using commercial and research instrumentation are presented and some possible solutions to these problems are considered.

Research paper thumbnail of Advanced Maintenance of Distribution Assets Through the Application of Predictive Techniques Using GE'S APM System: Real Case in a Spanish DSO

Lecture notes in mechanical engineering, 2023

Research paper thumbnail of Increase of capacity in electric arc-furnace steel mill factories by means of a demand-side management strategy and ampacity techniques

International Journal of Electrical Power & Energy Systems, 2021

An electric arc-furnace is a complex industry which demands high levels of electrical energy in o... more An electric arc-furnace is a complex industry which demands high levels of electrical energy in order to heat iron materials and other additives needed for the production of cast iron and/or steelmaking. The cost of the electrical energy demanded by the factory during the production can be greater than 20% of the overall cost. This kind of arc-furnace allows the production of steel with levels of scrap metal feedstock up to 100%. From an electrical point of view, the factory size in terms of its maximum apparent power demanded from the grid is designed to make use of the static capacity of the transmission line that supplies the energy. In that case, it is not possible to increase the power of the factory above the static rating by adding new facilites without installing new transmission infrastructures. This paper presents a methodology that allows an increase in net power of an arc-furnace factory without installing new transmission lines. The solution is based on a mix strategy that combines Demand-Side Management (DSM) methodologies and the use of ampacity techniques according IEEE 738 and CIGRE TB601. The application of DSM methodologies provides an improvement in the sustainability of not only the industrial customer but also in the overall grid. As a

Research paper thumbnail of Power Quality – Monitoring, Analysis and Enhancement

Research paper thumbnail of Criterios Para Una Facturación De La Energía Eléctrica Más Equitativa

Research paper thumbnail of BIodIVersIty Indexes APPlIed to the AnAlysIs oF suPPly securIty In Power systems

Interciencia, 2011

In the last decade the growth in electricity demand in Spain was~ 4.5% annually; capacity and ene... more In the last decade the growth in electricity demand in Spain was~ 4.5% annually; capacity and energy demand forecasts estimate that this growth will continue, but at a lower rate (MITC, 2006). Table I shows the power generation mix that has almost entirely covered the ...

Research paper thumbnail of Electrotecnia Para Ingenieros De Telecomunicación

Acceso de usuarios registrados. Acceso de usuarios registrados Usuario Contraseña. ...

Research paper thumbnail of Utilización De Las Pruebas Objetivas Para El Aprendizaje/Evaluación. Aplicación a La Ingeniería Eléctrica

… Educativa en las …, 2007

Acceso de usuarios registrados. Acceso de usuarios registrados Usuario Contraseña. ...

Research paper thumbnail of Techniques to Locate the Origin of Power Quality Disturbances in a Power System: A Review

Sustainability

The complexity in the power system topology, together with the new paradigm in generation and dem... more The complexity in the power system topology, together with the new paradigm in generation and demand, make achieving an adequate level of supply quality a complicated goal for distribution companies. The electrical system power quality is subject to different regulations. On one hand, EN-50160 establishes the characteristics of the voltage supplied by public electricity networks, therefore affecting distribution companies. On the other hand, the EN-61000 series of standards regulates the electromagnetic compatibility of devices connected to the network, therefore affecting the loads. Power companies and device manufacturers are both responsible and affected in the issue of quality of supply. Despite the regulations, there are certain aspects of the supply quality that are not solved. One of the most important is the location of the disturbance’s origin. This paper presents a review of the main techniques to locate the disturbance’s origin in the electric network through two approach...

Research paper thumbnail of Ferroresonance Detection in Voltage Transformers Through Vibration Monitoring

Applied Condition Monitoring, 2019

Ferroresonance is a very studied phenomenon by the distribution electrical companies since it can... more Ferroresonance is a very studied phenomenon by the distribution electrical companies since it can cause damage to transformers and other line elements. This problem is generated by the association in series or in parallel of capacities (overhead and underground power lines) and saturable inductances (voltage transformers). During the ferroresonance, the Voltage Transformer (VT) becomes saturated and the magnetic field varies in a high way; all this produces that the ferromagnetic material dimensions of the transformer change due to the phenomenon of magnetostriction. Thus, magnetostriction generates a vibration on the transformer. The main effects produced by ferroresonance are as follow: core saturation, voltage and current distortion, overvoltages and overcurrents, temperature increase, vibration and noise. The aim of this paper is to detect the ferroresonance by analyzing the vibration on the VT.

Research paper thumbnail of Ferroresonance Mitigation Device in Voltage Transformers with a Flyback based Resistor Emulator

2018 IEEE 19th Workshop on Control and Modeling for Power Electronics (COMPEL), 2018

A widely configurable and scalable resistor emulator actively mitigates the ferroresonance phenom... more A widely configurable and scalable resistor emulator actively mitigates the ferroresonance phenomenon. This paper proposes a new variety of mitigation equipment based on power electronic converters operated as resistor emulators. The presence of a ferroresonance activates a flyback converter operating in the critical conduction mode (CrCM) with no specific output voltage control. The severity of the resonance configures the emulated resistance value. Results show a fast and effective response of the proposed device in comparison with the state-of-the-art solutions

Research paper thumbnail of Determination of Transformer Oil Contamination from the OLTC Gases in the Power Transformers of a Distribution System Operator

Applied Sciences, 2020

Power transformers are considered to be the most important assets in power substations. Thus, the... more Power transformers are considered to be the most important assets in power substations. Thus, their maintenance is important to ensure the reliability of the power transmission and distribution system. One of the most commonly used methods for managing the maintenance and establishing the health status of power transformers is dissolved gas analysis (DGA). The presence of acetylene in the DGA results may indicate arcing or high-temperature thermal faults in the transformer. In old transformers with an on-load tap-changer (OLTC), oil or gases can be filtered from the OLTC compartment to the transformer’s main tank. This paper presents a method for determining the transformer oil contamination from the OLTC gases in a group of power transformers for a distribution system operator (DSO) based on the application of the guides and the knowledge of experts. As a result, twenty-six out of the 175 transformers studied are defined as contaminated from the OLTC gases. In addition, this paper ...

Research paper thumbnail of BIodIVers Ity I ndexes APP lIed to the A nAlys Is o F su PPly secur Ity I n Power systems

SUMMARY The evolution of the vulnerability of the Spanish power generation system with respect to... more SUMMARY The evolution of the vulnerability of the Spanish power generation system with respect to the primary energy resources has been assessed by three new indexes developed from biodiversity analysis. The first of these indexes measures, in percentage, the uniformity of the primary energy resources in the system. The second one quantifies the diversity by means of the equivalent number of primary energy resources that are present in similar proportions in the system. The third one allows the calculation of the diversity reduction in the system with the non-evenness of these primary energy resources. They have been applied to the energy results of a stochastic linear model, developed with the software GAMS, in order to demonstrate their usefulness. In this model several generation technologies have been considered (nuclear, clean coal technologies, etc), and also several scenarios of fossil fuel costs. The number of primary energy resources that have to be used depends on the degr...

Research paper thumbnail of Systems with Large-Scale Wind Energy Generation

This paper is devoted to the development of a methodology suitable to be used to determine the im... more This paper is devoted to the development of a methodology suitable to be used to determine the impact of of wind farms in distribution networks that are also supplied with other classical generation facilities based on thermal and hydraulic energy. The methodology is based on an automated nalysis varies the level of the electric generation f r both the and thermal generators by using PSS, Phyton user can define multiple scenarios considering wind, thermal and hydraulic generators o the line capacity can be computed and compared in order to know where the system located and which situations occur. All the results computed can be analysed in a single or compared way by using tables and plots and con sidering the static rate of the distribution lines. The developed system can also be applied to the computation of the sensitivity of the power flow to the variation of the parameters that define the power system.

Research paper thumbnail of A Methodology for the Calculation of Typical Gas Concentration Values and Sampling Intervals in the Power Transformers of a Distribution System Operator

Energies, 2020

Predictive maintenance strategies in power transformers aim to assess the risk through the calcul... more Predictive maintenance strategies in power transformers aim to assess the risk through the calculation and monitoring of the health index of the power transformers. The parameter most used in predictive maintenance and to calculate the health index of power transformers is the dissolved gas analysis (DGA). The current tendency is the use of online DGA monitoring equipment while continuing to perform analyses in the laboratory. Although the DGA is well known, there is a lack of published experimental data beyond that in the guides. This study used the nearest-rank method for obtaining the typical gas concentration values and the typical rates of gas increase from a transformer population to establish the optimal sampling interval and alarm thresholds of the continuous monitoring devices for each power transformer. The percentiles calculated by the nearest-rank method were within the ranges of the percentiles obtained using the R software, so this simple method was validated for this ...

Research paper thumbnail of Toward Energy Savings in Campus Buildings under a Life Cycle Thinking Approach

Applied Sciences, 2020

Recent studies have identified that buildings all over the world are great contributors to energy... more Recent studies have identified that buildings all over the world are great contributors to energy consumption and greenhouse gas emissions. The relationship between the building industry and environmental pollution is continuously discussed. The building industry includes many phases: extraction of raw materials, manufacturing, construction, use, and demolition. Each phase consumes a large amount of energy, and subsequent emissions are released. The life cycle energy assessment (LCEA) is a simplified version of the life cycle assessment (LCA) that focuses only on the evaluation of energy inputs for different phases of the life cycle. Operational energy is the energy required for day-to-day operation processes of buildings, such as heating, cooling and ventilation systems, lighting, as well as appliances. This use phase accounts for the largest portion of energy consumption of the life cycle of conventional buildings. In addition, energy performance certification of buildings is an o...

Research paper thumbnail of Soluciones Anti-Isla en Baja y Media Tensión

DYNA INGENIERIA E INDUSTRIA, 2020

Research paper thumbnail of Stream Data Cleaning for Dynamic Line Rating Application

Energies, 2018

The maximum current that an overhead transmission line can continuously carry depends on external... more The maximum current that an overhead transmission line can continuously carry depends on external weather conditions, most commonly obtained from real-time streaming weather sensors. The accuracy of the sensor data is very important in order to avoid problems such as overheating. Furthermore, faulty sensor readings may cause operators to limit or even stop the energy production from renewable sources in radial networks. This paper presents a method for detecting and replacing sequences of consecutive faulty data originating from streaming weather sensors. The method is based on a combination of (a) a set of constraints obtained from derivatives in consecutive data, and (b) association rules that are automatically generated from historical data. In smart grids, a large amount of historical data from different weather stations are available but rarely used. In this work, we show that mining and analyzing this historical data provides valuable information that can be used for detecting...

Research paper thumbnail of Robust Optimization of Energy Hubs Operation Based on Extended Affine Arithmetic

Energies, 2019

Traditional energy systems were planned and operated independently, but the diffusion of distribu... more Traditional energy systems were planned and operated independently, but the diffusion of distributed and renewable energy systems led to the development of new modeling concepts, such as the energy hub. The energy hub is an integrated paradigm, based on the challenging idea of multi-carrier energy systems, in which multiple inputs are conditioned, converted and stored in order to satisfy different types of energy demand. To solve the energy hub optimal scheduling problem, uncertainty sources, such as renewable energy production, price volatility and load demand, must be properly considered. This paper proposes a novel methodology, based on extended Affine Arithmetic, which enables the solving of the optimal scheduling problem in the presence of multiple and heterogeneous uncertainty sources. Realistic case studies are presented and discussed in order to show the effectiveness of the proposed methodology.

Research paper thumbnail of Problems Derived from the Simultaneous Utilisation of Different Flickermeters in Large Electric Networks

Renewable Energy and Power Quality Journal, 2003

Power Quality assessment in distribution networks requires distributed measurements in order to v... more Power Quality assessment in distribution networks requires distributed measurements in order to verify the PQ state of the art. This process cannot simply be considered as an extension of a measurement at a given point because several variables need to be considered: number of PQM; election of optimal measurement location; synchronisation of instrumentation and management of captured data. This work focuses on the problems related with the simultaneous utilisation of different flickermeters in large electric networks. From a classical instrumentation point of view, several flickermeters from different customers are tested in the laboratory in order to determine the differences in the accuracy of the results. Both Pst and Plt are statistical parameters calculated using a large number of samples of the instantaneous flicker level I FL. The number of captured samples can vary from one instrument to another, so different flickermeters provide different values.

Research paper thumbnail of Influence on Power Quality Measurement of the Simultaneous Presence of Different Disturbances

Renewable Energy and Power Quality Journal, 2003

Power Quality measurements involve not only problems related with the real use of recorders but a... more Power Quality measurements involve not only problems related with the real use of recorders but also theoretical questions connected with functional and design aspects of the instrumentation. In addition, there are a rising number of standards covering topics from design to data analysis, so final users usually assume that they do not have to pay special attention to PQ instrumentation functionality when the device is designed according to approved standards. However, it is not unusual to find different disturbances at the same point and in the same time and standards do not say anything about their mutual influence on PQ index. The main aim of this research work is to show the influence that having different disturbances (flicker and sags) simultaneously has on the final results provided by the instrumentation for each individual disturbance. The paper proposes a test system and a methodology. The results of various tests using commercial and research instrumentation are presented and some possible solutions to these problems are considered.