Articles de revistahttp://hdl.handle.net/2117/32772024-03-29T12:44:32Z2024-03-29T12:44:32ZAn appropriate index to assess the global cancellation level of the harmonic currents consumed by a set of single-phase uncontrolled rectifiers and a set of fluorescent lampsMesas García, Juan JoséSainz Sapera, LuisMonjo Mur, LluísPedra Durán, Joaquimhttp://hdl.handle.net/2117/3708452022-07-24T15:54:08Z2022-07-21T13:12:32ZAn appropriate index to assess the global cancellation level of the harmonic currents consumed by a set of single-phase uncontrolled rectifiers and a set of fluorescent lamps
Mesas García, Juan José; Sainz Sapera, Luis; Monjo Mur, Lluís; Pedra Durán, Joaquim
An in-depth study of harmonic current reduction in European commercial buildings due to the harmonic cancellation effect when a set of single-phase uncontrolled rectifiers and a set of fluorescent lamps are connected at the same voltage level is essential, since both types of non-linear loads are very present in commercial and residential sectors. This paper provides an appropriate index to assess the global cancellation level of the harmonic currents for this study. The equivalent circuit per phase of the typical three-phase power system of European commercial installations is presented and simplified for the cancellation analysis of the harmonic currents consumed by a set of multiple identical single-phase uncontrolled rectifiers and a set of multiple identical fluorescent lamps connected at the same voltage level. The suitability and usefulness of the proposed index are shown by applying it to that analysis, which leads to some results of practical interest. This index can be generalized to any number of sets of multiple identical non-linear loads and can be applied in graphical and optimization studies that will allow a greater benefit from the harmonic cancellation effect to be obtained given the global nature of the index.
2022-07-21T13:12:32ZMesas García, Juan JoséSainz Sapera, LuisMonjo Mur, LluísPedra Durán, JoaquimAn in-depth study of harmonic current reduction in European commercial buildings due to the harmonic cancellation effect when a set of single-phase uncontrolled rectifiers and a set of fluorescent lamps are connected at the same voltage level is essential, since both types of non-linear loads are very present in commercial and residential sectors. This paper provides an appropriate index to assess the global cancellation level of the harmonic currents for this study. The equivalent circuit per phase of the typical three-phase power system of European commercial installations is presented and simplified for the cancellation analysis of the harmonic currents consumed by a set of multiple identical single-phase uncontrolled rectifiers and a set of multiple identical fluorescent lamps connected at the same voltage level. The suitability and usefulness of the proposed index are shown by applying it to that analysis, which leads to some results of practical interest. This index can be generalized to any number of sets of multiple identical non-linear loads and can be applied in graphical and optimization studies that will allow a greater benefit from the harmonic cancellation effect to be obtained given the global nature of the index.Frequency domain stability assessment of photovoltaic power generation systems with quasi-z-source invertersSainz Sapera, LuisMonjo Mur, Lluíshttp://hdl.handle.net/2117/3598622022-05-19T11:04:37Z2022-01-18T08:31:29ZFrequency domain stability assessment of photovoltaic power generation systems with quasi-z-source inverters
Sainz Sapera, Luis; Monjo Mur, Lluís
Photovoltaic power generation systems are one of the main renewable power sources, and quasi-Z-source inverters are becoming powerful devices to integrate these systems in AC grids. However, stability issues due to the damping behaviour of converters must be considered. There are several studies in this direction but instability concerns are not completely solved yet. This paper contributes with a procedure for the stability assessment of photovoltaic power generation systems with quasiZ-source inverters in the frequency domain. The study is based on the small-signal averaged model of the system expressed in the s-domain and the stability criterion derived from the frequency characteristics of the state-space matrix. The influence of the photovoltaic power generation system operating point on stability is studied by the proposed procedure. Eigenvalue analysis and PSCAD/EMTDC simulations are also performed to validate the obtained results.
2022-01-18T08:31:29ZSainz Sapera, LuisMonjo Mur, LluísPhotovoltaic power generation systems are one of the main renewable power sources, and quasi-Z-source inverters are becoming powerful devices to integrate these systems in AC grids. However, stability issues due to the damping behaviour of converters must be considered. There are several studies in this direction but instability concerns are not completely solved yet. This paper contributes with a procedure for the stability assessment of photovoltaic power generation systems with quasiZ-source inverters in the frequency domain. The study is based on the small-signal averaged model of the system expressed in the s-domain and the stability criterion derived from the frequency characteristics of the state-space matrix. The influence of the photovoltaic power generation system operating point on stability is studied by the proposed procedure. Eigenvalue analysis and PSCAD/EMTDC simulations are also performed to validate the obtained results.Experimental technique to analyze the influence of cutting conditions on specific energy consumption during abrasive metal cutting with thin discsAwan, Muhammad RizwanGonzález Rojas, Hernán AlbertoPerat Benavides, Josep IgnasiHameed, Saqibhttp://hdl.handle.net/2117/3516252024-03-10T05:15:45Z2021-09-17T11:23:37ZExperimental technique to analyze the influence of cutting conditions on specific energy consumption during abrasive metal cutting with thin discs
Awan, Muhammad Rizwan; González Rojas, Hernán Alberto; Perat Benavides, Josep Ignasi; Hameed, Saqib
Specific energy consumption is an important indicator for a better understanding of the machinability of materials. The present study aims to estimate the specific energy consumption for abrasive metal cutting with ultra-thin discs at comparatively low and medium feed rates. Using an experimental technique, the cutting power was measured at four predefined feed rates for S235JR, intermetallic Fe-Al(40%), and C45K with different thermal treatments. The variation in the specific energy consumption with the material removal rate was analyzed through an empirical model, which enabled us to distinguish three phenomena of energy dissipation during material removal. The thermal treatment and mechanical properties of materials have a significant impact on the energy consumption pattern, its corresponding components, and cutting power. Ductile materials consume more specific cutting energy than brittle materials. The specific cutting energy is the minimum energy required to remove the material, and plowing energy is found to be the most significant phenomenon of energy dissipation.
2021-09-17T11:23:37ZAwan, Muhammad RizwanGonzález Rojas, Hernán AlbertoPerat Benavides, Josep IgnasiHameed, SaqibSpecific energy consumption is an important indicator for a better understanding of the machinability of materials. The present study aims to estimate the specific energy consumption for abrasive metal cutting with ultra-thin discs at comparatively low and medium feed rates. Using an experimental technique, the cutting power was measured at four predefined feed rates for S235JR, intermetallic Fe-Al(40%), and C45K with different thermal treatments. The variation in the specific energy consumption with the material removal rate was analyzed through an empirical model, which enabled us to distinguish three phenomena of energy dissipation during material removal. The thermal treatment and mechanical properties of materials have a significant impact on the energy consumption pattern, its corresponding components, and cutting power. Ductile materials consume more specific cutting energy than brittle materials. The specific cutting energy is the minimum energy required to remove the material, and plowing energy is found to be the most significant phenomenon of energy dissipation.Application work using software tools and didactic equipment of electrical machines in electrical engineering studiesTorrent Burgués, MarcelMartínez Piera, EusebioPerat Benavides, Josep Ignasihttp://hdl.handle.net/2117/3464622021-09-05T10:01:42Z2021-06-01T11:47:09ZApplication work using software tools and didactic equipment of electrical machines in electrical engineering studies
Torrent Burgués, Marcel; Martínez Piera, Eusebio; Perat Benavides, Josep Ignasi
This article describes the use of software tools and didactic equipment of electrical machines applied to the teaching in electrical engineering, specifically in the realization of an application work consisting of the characterization of the three-phase induction motor. Several studies have explored the effectiveness of teaching activities, which encompass different learning tools in the same work, from the use of didactic materials to the use of professional computer tools. The objective is the simultaneous use of didactic equipment and the calculation methodologies through specific software of industrial applications in engineering studies. In addition, to observe whether performing application work that implementing different techniques at the same time fosters the critical spirit among students. The activities students must do in the application work proposed in the subject of rotating electrical machines is to determine all the constructive variables of an induction motor, draw it, simulate its electromagnetic behavior by finite element method with a freeware available 2D program, test the motor in the laboratory following the guidelines of the current standards and, finally, compare the results obtained from the tests and the simulation, by making a critique of the results and the calculation methodology used. The application work presented in the article has been implemented during several courses in the subject of electrical machines for electrical engineering students, with satisfactory results.
2021-06-01T11:47:09ZTorrent Burgués, MarcelMartínez Piera, EusebioPerat Benavides, Josep IgnasiThis article describes the use of software tools and didactic equipment of electrical machines applied to the teaching in electrical engineering, specifically in the realization of an application work consisting of the characterization of the three-phase induction motor. Several studies have explored the effectiveness of teaching activities, which encompass different learning tools in the same work, from the use of didactic materials to the use of professional computer tools. The objective is the simultaneous use of didactic equipment and the calculation methodologies through specific software of industrial applications in engineering studies. In addition, to observe whether performing application work that implementing different techniques at the same time fosters the critical spirit among students. The activities students must do in the application work proposed in the subject of rotating electrical machines is to determine all the constructive variables of an induction motor, draw it, simulate its electromagnetic behavior by finite element method with a freeware available 2D program, test the motor in the laboratory following the guidelines of the current standards and, finally, compare the results obtained from the tests and the simulation, by making a critique of the results and the calculation methodology used. The application work presented in the article has been implemented during several courses in the subject of electrical machines for electrical engineering students, with satisfactory results.Two-phase linear hybrid reluctance actuator with low detent forceGarcia Amoros, JordiMarin Genesca, MarcAndrada Gascón, PedroMartínez Piera, Eusebiohttp://hdl.handle.net/2117/3308652021-09-05T01:42:31Z2020-10-27T11:58:02ZTwo-phase linear hybrid reluctance actuator with low detent force
Garcia Amoros, Jordi; Marin Genesca, Marc; Andrada Gascón, Pedro; Martínez Piera, Eusebio
In this paper, a novel two-phase linear hybrid reluctance actuator with the double-sided segmented stator, made of laminated U cores, and an interior mover with permanent magnets is proposed. The permanent magnets are disposed of in a way that increases the thrust force of a double-sided linear switched reluctance actuator of the same size. To achieve this objective, each phase of the actuator is powered by a single H-bridge inverter. To reduce the detent force, the upper and the lower stator were shifted. Finite element analysis was used to demonstrate that the proposed actuator has a high force density with low detent force. In addition, a comparative study between the proposed linear hybrid reluctance actuator, linear switched reluctance, and linear permanent magnet actuators of the same size was performed. Finally, experimental tests carried out in a prototype confirmed the goals of the proposed actuator.
2020-10-27T11:58:02ZGarcia Amoros, JordiMarin Genesca, MarcAndrada Gascón, PedroMartínez Piera, EusebioIn this paper, a novel two-phase linear hybrid reluctance actuator with the double-sided segmented stator, made of laminated U cores, and an interior mover with permanent magnets is proposed. The permanent magnets are disposed of in a way that increases the thrust force of a double-sided linear switched reluctance actuator of the same size. To achieve this objective, each phase of the actuator is powered by a single H-bridge inverter. To reduce the detent force, the upper and the lower stator were shifted. Finite element analysis was used to demonstrate that the proposed actuator has a high force density with low detent force. In addition, a comparative study between the proposed linear hybrid reluctance actuator, linear switched reluctance, and linear permanent magnet actuators of the same size was performed. Finally, experimental tests carried out in a prototype confirmed the goals of the proposed actuator.Surface damaging of brass and steel pins when sliding over nitrided samples cut by finishing and roughing EDM conditionsMartynenko, VitaliMartinez Krahmer, DanielNápoles Alberro, AmeliaCabo, AmadoPérez, DanielaZayas Figueras, Enrique ErnestoGonzález Rojas, Hernán AlbertoSánchez Egea, Antonio Joséhttp://hdl.handle.net/2117/3271222024-03-10T04:52:22Z2020-07-20T11:50:48ZSurface damaging of brass and steel pins when sliding over nitrided samples cut by finishing and roughing EDM conditions
Martynenko, Vitali; Martinez Krahmer, Daniel; Nápoles Alberro, Amelia; Cabo, Amado; Pérez, Daniela; Zayas Figueras, Enrique Ernesto; González Rojas, Hernán Alberto; Sánchez Egea, Antonio José
In the forging industry, surface quality and surface treatments of dies are crucial parameters to extend their life. These components are usually machined by milling or by Electrical Discharge Machining (EDM), and the final surface roughness depends on the machining techniques and operational conditions used in its fabrication. After milling, a nitriding treatment is widely applied to extend its service life. Nevertheless, no scientific report that informs about nitriding after EDM has been found. Accordingly, this work focuses on the wear and friction behavior of pins made of brass and medium carbon steel sliding over AISI H13 discs, made by wire EDM in the conditions of finishing and roughing. The discs are plasma nitride, and their effect on the wear during pin-ondisc tests is evaluated. In this sense, the analysis of the surface damage for the different pins will help us to understand the service life and wear evolution of the forging dies. The results show that plasma nitride reduces the friction and prevents the degradation of the pin, independently of the material of the pin, when sliding over finishing and roughing EDM conditions.
2020-07-20T11:50:48ZMartynenko, VitaliMartinez Krahmer, DanielNápoles Alberro, AmeliaCabo, AmadoPérez, DanielaZayas Figueras, Enrique ErnestoGonzález Rojas, Hernán AlbertoSánchez Egea, Antonio JoséIn the forging industry, surface quality and surface treatments of dies are crucial parameters to extend their life. These components are usually machined by milling or by Electrical Discharge Machining (EDM), and the final surface roughness depends on the machining techniques and operational conditions used in its fabrication. After milling, a nitriding treatment is widely applied to extend its service life. Nevertheless, no scientific report that informs about nitriding after EDM has been found. Accordingly, this work focuses on the wear and friction behavior of pins made of brass and medium carbon steel sliding over AISI H13 discs, made by wire EDM in the conditions of finishing and roughing. The discs are plasma nitride, and their effect on the wear during pin-ondisc tests is evaluated. In this sense, the analysis of the surface damage for the different pins will help us to understand the service life and wear evolution of the forging dies. The results show that plasma nitride reduces the friction and prevents the degradation of the pin, independently of the material of the pin, when sliding over finishing and roughing EDM conditions.Predictive maintenance plan for switched reluctance motor drivesSánchez López, José AntonioAndrada Gascón, PedroBlanqué Molina, BalduinoTorrent Burgués, Marcelhttp://hdl.handle.net/2117/1920832023-02-19T03:51:42Z2020-07-01T08:44:47ZPredictive maintenance plan for switched reluctance motor drives
Sánchez López, José Antonio; Andrada Gascón, Pedro; Blanqué Molina, Balduino; Torrent Burgués, Marcel
In a near future when Industry 4.0 is implanted, predictive maintenance will have a much more prominent role than that currently plays in traditional industry. Predictive maintenance is the organized monitoring with periodic or continuous measurement of variables of the state of the equipment to be maintained and its comparison with pre-established patterns for the determination of the instant in which the maintenance intervention should take place. Three-phase induction motor drives are one of the industrial equipment that has been given greater attention regarding predictive maintenance plans. In recent years, switched reluctance motor drives have begun to have some relevance in the industry. In this paper, after a brief review of the switched reluctance motors and their control, an analysis of the different types of faults and a description of the most usual diagnostic techniques in electric drives, a predictive maintenance plan for switched reluctance motor drives is proposed. This predictive maintenance plan considers different control strategies (hysteresis and single pulse), and is based on diagnostic techniques such as analysis of currents and spectral analysis of vibrations. Exhaustive experimental tests have been carried out in order to validate the proposed plan.
2020-07-01T08:44:47ZSánchez López, José AntonioAndrada Gascón, PedroBlanqué Molina, BalduinoTorrent Burgués, MarcelIn a near future when Industry 4.0 is implanted, predictive maintenance will have a much more prominent role than that currently plays in traditional industry. Predictive maintenance is the organized monitoring with periodic or continuous measurement of variables of the state of the equipment to be maintained and its comparison with pre-established patterns for the determination of the instant in which the maintenance intervention should take place. Three-phase induction motor drives are one of the industrial equipment that has been given greater attention regarding predictive maintenance plans. In recent years, switched reluctance motor drives have begun to have some relevance in the industry. In this paper, after a brief review of the switched reluctance motors and their control, an analysis of the different types of faults and a description of the most usual diagnostic techniques in electric drives, a predictive maintenance plan for switched reluctance motor drives is proposed. This predictive maintenance plan considers different control strategies (hysteresis and single pulse), and is based on diagnostic techniques such as analysis of currents and spectral analysis of vibrations. Exhaustive experimental tests have been carried out in order to validate the proposed plan.Design of a novel modular axial-flux double rotor switched reluctance driveAndrada Gascón, PedroBlanqué Molina, BalduinoMartínez Piera, EusebioPerat Benavides, Josep IgnasiSánchez López, José AntonioTorrent Burgués, Marcelhttp://hdl.handle.net/2117/1916202023-02-19T03:54:30Z2020-06-26T07:53:11ZDesign of a novel modular axial-flux double rotor switched reluctance drive
Andrada Gascón, Pedro; Blanqué Molina, Balduino; Martínez Piera, Eusebio; Perat Benavides, Josep Ignasi; Sánchez López, José Antonio; Torrent Burgués, Marcel
Nowadays, there is a renewed interest in switched reluctance machines and especially in axial-flux switched reluctance machines (AFSRM). This paper presents a comprehensive design procedure for modular AFSRM with an inner stator and two exterior rotors that have a new distribution of the stator and rotor poles, resulting in short magnetic paths with no flux reversal. After a description of the proposed machine, the output torque equation is derived from a simplified non-linear energy conversion loop and guidelines for its design are given. Once the preliminary sizing has been carried out the different modules of the AFSRM, the magnetically active parts made with SMC, are reshaped or refined using 3D printing and 3D electromagnetic finite element analysis until they reach their definitive shape and dimensions. Finally, an AFSRM has been built following the proposed design procedure and has been validated by experimental measurements
2020-06-26T07:53:11ZAndrada Gascón, PedroBlanqué Molina, BalduinoMartínez Piera, EusebioPerat Benavides, Josep IgnasiSánchez López, José AntonioTorrent Burgués, MarcelNowadays, there is a renewed interest in switched reluctance machines and especially in axial-flux switched reluctance machines (AFSRM). This paper presents a comprehensive design procedure for modular AFSRM with an inner stator and two exterior rotors that have a new distribution of the stator and rotor poles, resulting in short magnetic paths with no flux reversal. After a description of the proposed machine, the output torque equation is derived from a simplified non-linear energy conversion loop and guidelines for its design are given. Once the preliminary sizing has been carried out the different modules of the AFSRM, the magnetically active parts made with SMC, are reshaped or refined using 3D printing and 3D electromagnetic finite element analysis until they reach their definitive shape and dimensions. Finally, an AFSRM has been built following the proposed design procedure and has been validated by experimental measurementsSynchronized switching modulation to reduce the DC-link current in SRM drivesCabezuelo, DavidKortabarria, IñigoAndreu, JonUgalde, UnaiBlanqué Molina, BalduinoAndrada Gascón, Pedrohttp://hdl.handle.net/2117/1915322020-07-23T20:14:43Z2020-06-25T11:20:50ZSynchronized switching modulation to reduce the DC-link current in SRM drives
Cabezuelo, David; Kortabarria, Iñigo; Andreu, Jon; Ugalde, Unai; Blanqué Molina, Balduino; Andrada Gascón, Pedro
Switched Reluctance Machines (SRM) are emerging as a possible alternative in terms of cost and supply stability to rare earth based electric vehicle traction systems. However, because of the huge amounts of energy stored and transferred back and forth between the DC source and the SRM, large DC-link capacitors must be used as buffers, which increases overall costs and size. This paper proposes a novel modulation technique which forces the exchange of energy between phases while decreasing the energy transfer between the DC bus and the SRM. This means lower DC bus currents (capacitor size and cost reduction) and lower Joule-effect conduction losses (better efficiency). The proposed modulation has been validated experimentally in a test bench and compared with the conventional torque-sharing function.
2020-06-25T11:20:50ZCabezuelo, DavidKortabarria, IñigoAndreu, JonUgalde, UnaiBlanqué Molina, BalduinoAndrada Gascón, PedroSwitched Reluctance Machines (SRM) are emerging as a possible alternative in terms of cost and supply stability to rare earth based electric vehicle traction systems. However, because of the huge amounts of energy stored and transferred back and forth between the DC source and the SRM, large DC-link capacitors must be used as buffers, which increases overall costs and size. This paper proposes a novel modulation technique which forces the exchange of energy between phases while decreasing the energy transfer between the DC bus and the SRM. This means lower DC bus currents (capacitor size and cost reduction) and lower Joule-effect conduction losses (better efficiency). The proposed modulation has been validated experimentally in a test bench and compared with the conventional torque-sharing function.Angular velocity analysis boosted by machine learning for helping in the differential diagnosis of Parkinson’s Disease and Essential TremorLoaiza Duque, Julián DavidSánchez Egea, Antonio JoséReeb, TheresaGonzález Rojas, Hernán AlbertoGonzález Vargas, Andrés Mauriciohttp://hdl.handle.net/2117/1880472024-03-10T12:46:15Z2020-05-19T08:58:44ZAngular velocity analysis boosted by machine learning for helping in the differential diagnosis of Parkinson’s Disease and Essential Tremor
Loaiza Duque, Julián David; Sánchez Egea, Antonio José; Reeb, Theresa; González Rojas, Hernán Alberto; González Vargas, Andrés Mauricio
Recent research has shown that smartphones/smartwatches have a high potential to help physicians to identify and differentiate between different movement disorders. This work aims to develop Machine Learning models to improve the differential diagnosis between patients with Parkinson’s Disease and Essential Tremor. For this purpose, we use a mobile phone’s built-in gyroscope to record the angular velocity signals of two different arm positions during the patient’s follow-up, more precisely, in rest and posture positions. To develop and to find the best classification models, diverse factors were considered, such as the frequency range, the training and testing divisions, the kinematic features, and the classification method. We performed a two-stage kinematic analysis, first to differentiate between healthy and trembling subjects and then between patients with Parkinson’s Disease and Essential Tremor. The models developed reached an average accuracy of 97.2+/-3.7% (98.5% Sensitivity, 93.3% Specificity)
to differentiate between Healthy and Trembling subjects and an average accuracy of 77.8+/-9.9% (75.7% Sensitivity, 80.0% Specificity) to discriminate between Parkinson’s Disease and Essential Tremor patients. Therefore, we conclude, that the angular velocity signal can be used to develop Machine Learning models for the differential diagnosis of Parkinson’s disease and Essential Tremor.
2020-05-19T08:58:44ZLoaiza Duque, Julián DavidSánchez Egea, Antonio JoséReeb, TheresaGonzález Rojas, Hernán AlbertoGonzález Vargas, Andrés MauricioRecent research has shown that smartphones/smartwatches have a high potential to help physicians to identify and differentiate between different movement disorders. This work aims to develop Machine Learning models to improve the differential diagnosis between patients with Parkinson’s Disease and Essential Tremor. For this purpose, we use a mobile phone’s built-in gyroscope to record the angular velocity signals of two different arm positions during the patient’s follow-up, more precisely, in rest and posture positions. To develop and to find the best classification models, diverse factors were considered, such as the frequency range, the training and testing divisions, the kinematic features, and the classification method. We performed a two-stage kinematic analysis, first to differentiate between healthy and trembling subjects and then between patients with Parkinson’s Disease and Essential Tremor. The models developed reached an average accuracy of 97.2+/-3.7% (98.5% Sensitivity, 93.3% Specificity)
to differentiate between Healthy and Trembling subjects and an average accuracy of 77.8+/-9.9% (75.7% Sensitivity, 80.0% Specificity) to discriminate between Parkinson’s Disease and Essential Tremor patients. Therefore, we conclude, that the angular velocity signal can be used to develop Machine Learning models for the differential diagnosis of Parkinson’s disease and Essential Tremor.