A precise, General, Non-Invasive and Automatic Speed Estimation Method for MCSA Steady-State Diagnosis and Efficiency Estimation of Induction Motors in the 4.0 Industry

Tesis por compendio[ES] Hay dos aspectos cruciales a la hora de operar motores de inducción en la industria: la estimación de su eficiencia (para minimizar el consumo de energía) y su diagnóstico (para evitar paradas intempestivas y reducir los costes de mantenimiento). Para estimar la eficiencia del motor es necesario medir tensiones y corrientes. Por ello, resulta conveniente y muy útil utilizar la misma corriente para diagnosticar también el motor (Motor Current Signature Analysis: MCSA). En este sentido, la técnica MCSA más adecuada es aquella basada en la localización de armónicos de fallo en el espectro de la corriente de línea del estator en régimen permanente, pues esta es la condición de funcionamiento de la mayoría de los motores de inducción de la industria. Por otro lado, dado que la frecuencia de estos armónicos depende de la velocidad, resulta imprescindible conocer esta magnitud con precisión, ya que esto permite localizar correctamente los armónicos de fallo, y, por tanto, reducir las posibilidades de falsos positivos/negativos. A su vez, una medida precisa de la velocidad también permite calcular con precisión la potencia mecánica, lo que se traduce en una estimación más exacta del rendimiento. Por último, para adaptarse a las necesidades de la Industria 4.0, en la que se monitoriza continuamente un gran número de motores, la velocidad también debe ser obtenida de manera no invasiva, automática y para cualquier motor de inducción. A este respecto, dado que la medición precisa de la velocidad a través de un encóder es invasiva y costosa, las técnicas de estimación de velocidad sin sensores (SSE en inglés) se convierten en la mejor opción. En la primera parte de esta tesis se realiza un análisis exhaustivo de las familias de técnicas SSE presentes en la literatura técnica. Como se demuestra en ella, aquellos métodos basados en armónicos de ranura (RSHs en inglés) y en armónicos laterales de frecuencia rotacional (RFSHs) son potencialmente los únicos que pueden satisfacer todos los requisitos mencionados anteriormente. Sin embargo, como también se demuestra en esta parte, y hasta esta tesis, siempre había existido un compromiso entre la precisión (característica de los RSHs) y la aplicabilidad general del método (característica de los RFSHs). En la segunda parte, y núcleo de esta tesis, se presenta una metodología que acaba con este compromiso, proporcionando así el primer método de estimación de velocidad preciso, general, no invasivo y automático para el diagnóstico en estado estacionario MCSA y la estimación de la eficiencia de motores de inducción que operan en un contexto de Industria 4.0. Esto se consigue desarrollando una novedosa técnica basada en RSHs que, por primera vez en la literatura técnica, elimina la necesidad de conocer/estimar el número de ranuras del rotor, lo que había impedido hasta la fecha que estos métodos fueran de aplicación general. Esta técnica proporciona además un procedimiento fiable y automático para localizar la familia de RSHs en el espectro de la corriente de línea de un motor de inducción. De igual forma y sin la ayuda de un experto, la técnica es capaz de determinar los parámetros necesarios para estimar la velocidad a partir de los RSHs, utilizando medidas tomadas en régimen estacionario. La metodología es validada utilizando motores con diferentes características y tipos de alimentaciones, empleando para ello simulaciones, pruebas de laboratorio y 105 motores industriales. Además, se muestra un caso de aplicación industrial en el que el algoritmo desarrollado se implementa en un sistema de monitorización continua mediante MCSA, lo que acaba conduciendo al descubrimiento de un nuevo fallo en motores sumergibles de pozo profundo: el desgaste de los anillos de cortocircuito. Por último, se presenta una segunda aplicación directa para este tipo de motores derivada del procedimiento de detección de RSHs: el uso de estos armónicos para diagnosticar, en fase temprana, cortocircuitos entre espiras.[CA] Hi ha dos aspectes crucials a l'hora d'operar motors d'inducció en la indústria: l'estimació de la seua eficiència (per a minimitzar el consum d'energia) i el seu diagnòstic (per a evitar parades intempestives i reduir els costos de manteniment). Per a estimar l'eficiència del motor és necessari mesurar tensions i corrents. Per això, resulta convenient i molt útil utilitzar el mateix corrent per a diagnosticar també el motor (Motor Current Signature Analysis: MCSA). En aquest sentit, la tècnica MCSA més adequada és aquella basada en la localització d'harmònics de fallada en l'espectre del corrent de línia de l'estator en règim permanent, ja que aquesta és la condició de funcionament de la majoria dels motors d'inducció de la indústria. D'altra banda, atés que la freqüència d'aquests harmònics depén de la velocitat, resulta imprescindible conéixer aquesta magnitud amb precisió, ja que això permet localitzar correctament els harmònics de fallada i, per tant, reduir les possibilitats de falsos positius/negatius. Al seu torn, una mesura precisa de la velocitat també permet calcular amb precisió la potència mecànica, la qual cosa es tradueix en una estimació més exacta del rendiment. Finalment, per a adaptar-se a les necessitats de la Indústria 4.0, en la qual es monitora contínuament un gran nombre de motors, la velocitat també ha de ser obtinguda de manera no invasiva, automàtica i per a qualsevol motor d'inducció. En aquest sentit, atès que el mesurament precís de la velocitat a través d'un encóder és invasiva i costosa, les tècniques d'estimació de velocitat sense sensors (SSE en anglés) es converteixen en la millor opció. En la primera part d'aquesta tesi es realitza una anàlisi exhaustiva de totes les famílies de tècniques SSE presents en la literatura tècnica. Com es demostra en ella, aquells mètodes basats en harmònics de ranura (RSHs en anglès) i harmònics laterals de freqüència rotacional (RFSHs en anglés) són els més prometedors, ja que son potencialment els únics que poden satisfer tots els requisits esmentats anteriorment. No obstant això, com també es demostra en aquesta part, i fins a aquesta tesi, sempre havia existit un compromís entre la precisió (característica dels RSHs) i l'aplicabilitat general del mètode (característica dels RFSHs). En la segona part, i nucli d'aquesta tesi, es presenta una metodologia que acaba amb aquest compromís, proporcionant així el primer mètode d'estimació de velocitat precís, general, no invasiu i automàtic per al diagnòstic en estat estacionari MCSA i l'estimació de l'eficiència de motors d'inducció que operen en un context d'Indústria 4.0. Això s'aconsegueix desenvolupant una nova tècnica basada en RSHs que, per primera vegada en la literatura tècnica, elimina la necessitat de conéixer/estimar el nombre de ranures del rotor, cosa que havia impedit fins avui que aquests mètodes foren d'aplicació general. Aquesta tècnica proporciona a més un procediment fiable i automàtic per a localitzar la família de RSHs en l'espectre del corrent de línia d'un motor d'inducció. De la mateixa forma i sense l'ajuda d'un expert, la tècnica és capaç de determinar els paràmetres necessaris per a estimar la velocitat a partir dels RSHs, utilitzant mesures preses en règim estacionari. La metodologia és validada utilitzant motors amb diferents característiques i condicions d'alimentació, emprant per a això simulacions, proves de laboratori i 105 motors industrials. A més, es mostra un cas real d'aplicació industrial en el qual l'algoritme desenvolupat és implementat en un sistema de monitoratge continu mitjançant MCSA, la qual cosa acaba conduint al descobriment d'una nova fallada en motors submergibles de pou profund: el desgast dels anells de curtcircuit. Finalment, es presenta una segona aplicació directa per a aquest tipus de motors derivada del procediment de detecció de RSHs: l'ús d'aquests harmònics per a diagnosticar, en fase primerenca, curtcircuits entre espires.[EN] There are two crucial aspects when operating induction motors in industry: efficiency estimation (to minimize energy consumption) and diagnosis (to avoid untimely outages and reduce maintenance costs). To estimate the motor's efficiency, it is necessary to measure voltages and currents. Hence, it is convenient and very useful using the same current to also diagnose the motor (Motor Current Signature Analysis: MCSA). In this regard, the most suitable MCSA technique is that based on locating fault harmonics in the spectrum of the stator line current under steady-state, as this is the operating condition of most induction motors in industry. Since the frequency of these harmonics depends on the speed, it becomes essential to be able to know this magnitude with precision, as this makes it possible to correctly locate the fault harmonics, and therefore, reduce the chances of false positives/negatives. In turn, an accurate speed information also allows to calculate the mechanical power with precision, which results in a more accurate estimation of the motor performance. Finally, to adapt to the needs of 4.0 Industry, where large numbers of motors are continuously monitored, the speed must not only be obtained very accurately, but also non-invasively, automatically (without the need for an expert) and for any induction motor. In this regard, since precise speed measurement through a shaft sensor is invasive and expensive, Sensorless Speed Estimation (SSE) techniques become the best option. The first part of this thesis conducts a thorough analysis of all the families of SSE techniques present in the technical literature. As demonstrated therein, those techniques based on Slotting and Rotational Frequency Sideband Harmonics are the most promising, as they can potentially meet all the aforementioned requirements. However, as also proved in this part, and up to this thesis, there had always been a trade-off between accuracy, characteristic of Rotor Slot Harmonics (RSHs), and general applicability, characteristic of Rotational Frequency Sideband Harmonics (RFSHs). The second part, and core of this thesis, presents a methodology that ends with this trade-off between accuracy and general applicability, thus providing the first precise, general, noninvasive and automatic speed estimation method for MCSA steady-state diagnosis and efficiency estimation of induction motors that operate in a 4.0 Industry context. This is achieved by developing a novel RSH-based technique that, for the first time in technical literature, eliminates the need to know/estimate the number of rotor slots, which had so far prevented these techniques to be generally applicable. This technique also provides a reliable and automatic procedure to, from among the high number of significant harmonics present in the spectrum of the line current of an induction motor, locate the RSHs family. Also automatically and without the help of an expert, the technique is able to determine the parameters needed to estimate speed from RSHs, using only measurements taken during the motor normal operation at steady-state. The methodology is validated using motors with different characteristics and supply conditions, by simulations, lab tests and with 105 industrial motors. Furthermore, a real industrial case of application is shown as well, where the speed estimation algorithm is implemented in a continuous motor condition monitoring system via MCSA, which eventually leads to the discovery of a new fault in deep-well submersible motors: the wear of end-rings. Finally, a second direct application derived from the reliable and automatic procedure to detect RSHs is presented: the use of these harmonics to diagnose early-stage inter-turn faults in induction motors of deep-well submersible pumps.Bonet Jara, J. (2023). A precise, General, Non-Invasive and Automatic Speed Estimation Method for MCSA Steady-State Diagnosis and Efficiency Estimation of Induction Motors in the 4.0 Industry [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/194269Compendi

A Precise, General, Non-Invasive and Automatic Speed Estimation Method for MCSA Diagnosis and Efficiency Estimation of Induction Motors

[EN] Efficiency estimation and diagnosis via MCSA require precise knowledge of speed. In an industrial environment, speed must be obtained with a non-invasive, automatic and general method. Recent studies have shown that Sensorless Speed Estimation techniques based on detecting Rotational Frequency Sideband Harmonics (RFSHs) or Rotor Slot Harmonics (RSHs) are best suited to these purposes. RFSHs-based methods are easier to apply as they only depend on the number of poles. RSHs-based are much more accurate due to their wider bandwidth. Yet, their use is not trivial as they require to identify the RSHs family, assign to each RSH its order of the current harmonic (¿) and determine the number of rotor slots (R), a rarely known parameter. This paper ends with this trade-off between accuracy and applicability by proposing a novel RSHs-based technique that, for the first time in technical literature, eliminates the need to estimate the number of rotor slots and provides a reliable and automatic procedure to locate the RSHs family and determine their ¿ indices. Finally, the method is validated under all types of conditions and motor designs, by simulations, lab tests and with 105 industrial motors, highlighting its high accuracy (errors below 0.05 rpm), and applicability.This work was supported by the Universitat Politecnica de Valencia and the Spanish Ministry of Science, Innovation and Universities [FPU19/02698]Bonet-Jara, J.; Pons Llinares, J. (2023). A Precise, General, Non-Invasive and Automatic Speed Estimation Method for MCSA Diagnosis and Efficiency Estimation of Induction Motors. IEEE Transactions on Energy Conversion. 38(2):1257-1267. https://doi.org/10.1109/TEC.2022.32208531257126738

A virtual laboratory for an enhanced and safe understanding of the electric transformers operation

[EN] The paper presents an educational software designed to simulate the behaviour of an electric transformer under no-load, shortcircuit and load test, measuring its input and output magnitudes through network analysers, and enabling the supply voltage and load regulations. This virtual laboratory allows to achieve several objectives. First, the student becomes familiar with the system to be operated in the real laboratory, reducing the subsequent electrical risk and optimizing the time required for carrying out the practice. Second, it enhances the understanding of transformers behaviour, its modelling through the equivalent electrical circuit, and the calculation of its two most characteristic parameters during its operation (performance and internal voltage drop). Finally, the application auto evaluates the transformer characterization performed by the student. The simulator reproduces schematically, but precisely, the assembly that the student faces during the lab lesson: an autotransformer to regulate the supply voltage, a transformer, two input and output network analysers, and different types of loads. The tool is structured in three panels. In the first panel, the student selects a transformer from 24 options, and performs its shortcircuit and no-load tests to characterize it through its electric equivalent circuit. Panels 2 and 3 enable load tests and its main characteristics calculation (performance and internal voltage drop). The student results are introduced in the app to perform auto-evaluation. To measure the performance and usefulness of the application, it has been implemented in the lab lessons of the subject ¿Electrical Technology¿, belonging to the Bachelor¿s Degree in Industrial Electronics and Automation Engineering, taught at the Polytechnic University of Valencia (Spain). The sample size is 96 students and the methodology used is as follows. The 96 students are subdivided into four groups. The practice lessons follow this sequence: a refreshment of the transformer concepts needed + explanation of the practice lesson to be performed + explanation and use of the app solving an example (only for groups 1 and 2) + real laboratory experience + final test on transformers. Finally, the performances between groups 1-2 and 3-4 are compared. It is observed that the students of groups 1 and 2 obtain better results in the final tests than those of groups 3 and 4, reaching higher levels of learning thanks to the previous use of the simulator. On the other hand, it is also observed that the time of completion of the real laboratory practice decreases substantially in groups 1 and 2. As a conclusion, there is a great benefit in using this application specifically designed to obtain very specific learning results, since the application is fully adapted to the needs of the degree and therefore to the level of knowledge that the students need to acquire according to the perception and experience of the teaching staff. Finally, based on the results, the application is permanently implemented in the laboratory lessons of Electrical Technology.This project is supported by Universitat Politècnica de València through the Project of Innovation and Educational Improvement Program (PIME 2018-2019/B26).Bonet-Jara, J.; Pons Llinares, J.; Bernal-Perez, S.; Sabater I Serra, R. (2019). A virtual laboratory for an enhanced and safe understanding of the electric transformers operation. IATED. 9177-9186. https://doi.org/10.21125/inted.2019.2277S9177918

Development of an e-learning platform for improving and assessing the student outcomes in electrical engineering

[EN] In the European Higher Education Area, the concept of `education¿ can be defined as a process that facilitates learning. The process will culminate successfully if our students have really learned and not necessarily because we have taught them. Taking into account the educational environment in which we are immersed, the learning process must be turned into a process where the students become aware of their goals and the teacher is transformed into a guide that escorts the students towards the achievement of the objectives. The organization of teaching in this environment involves developing new conceptualizations and methodologies, which can be applied jointly to classical methodologies, acting in a complementary and also synergistic manner. Currently, all academic institutions use virtual campus platforms for educational purposes. At the Universitat Politècnica de València (Spain), this virtual system can be used as a repository of academic material but also has tools for the development of applications based on e-learning. In the present paper, an e-learning platform has been designed for students of electronic engineering that guide the learners to understand theoretical concepts, integrate theory and practice, and apply knowledge and skills to develop a viable solution to specific problems. The importance of defining and assessing learning outcomes, that is, the competences that students should have acquired and can use, have also been considered. To achieve this goal, a problem-based learning approach has been used so the students learn to identify and interpret data and design strategies to solve problems applying concepts of analysis of electrical circuits. First, the most relevant competences that the students must achieve has been analysed (`Knowledge and use of the principles of theory of circuits and electric machines¿, `Applied knowledge of electrical engineering¿ and `Analysis and resolution of problems¿). Based on them, a battery of tests and tasks has been designed, in order to reinforce the theoretic concepts and analyse and solve problems. The `Test & Quizzes¿ tool of the system has been used to develop the e-learning platform, in which selfevaluation has been also integrated in order to become an effective instrument for learning. The focus has been put on the design of the strategy in relation to the competences that students should acquire, the experience gained during the development of the e-learning platform and the students¿ satisfaction after the implementation.This project is supported by Universitat Politècnica de València through the Project of Innovation and Educational Improvement Program (PIME 2018-2019/B26).Pons Llinares, J.; Bernal-Perez, S.; García-Sánchez, TM.; Bonet-Jara, J.; Sabater I Serra, R. (2019). Development of an e-learning platform for improving and assessing the student outcomes in electrical engineering. IATED. 9169-9176. https://doi.org/10.21125/inted.2019.2276S9169917

Desarrollo de un programa para la determinación del régimen dinámico de motores de jaula de ardilla. Aplicación al análisis de los transitorios industriales usuales y a los provocados por averías

[ES] Se desarrollará mediante Matlab un programa para la simulación, en el caso más general, del comportamiento dinámico de motores asíncronos de jaula de ardilla con un número arbitrario de barras en el rotor. Se incluirá el efecto de los armónicos espaciales y, a diferencia de otros programas, se tendrá en cuenta la realidad (que supone una gran dificultad para el análisis) de que en el rotor de jaula no hay fases individuales propiamente dichas, es decir, circuitos cerrados recorridos por una misma corriente. Esta primera fase del TFM toma como punto de arranque un Proyecto Fin de Carrera dirigido anteriormente por el primer tutor del presente TFM. La medida experimental con una mínima precisión de pares transitorios de varios cientos de hercios (e incluso en la región de los kHz) en el eje de una máquina eléctrica requiere un equipo de costo muy elevado, y del que no se dispone en el Departamento (ni tampoco en muchos centros de investigación). Por ello, y para obtener, no obstante, una seguridad razonable en la validez del programa desarrollado, se procederá primero a su comparación con otros varios programas, desarrollados desde una perspectiva física diferente, y que sólo son válidos para estructuras estator-rotor correspondientes a casos más sencillos. Se comprobará que, en todos esos casos más sencillos, los resultados obtenidos son iguales. A continuación, se aplicará el programa general para el análisis de los transitorios usuales y de los provocados por averías. Entre los primeros se puede citar el arranque del motor en conexión directa a red, el cambio brusco de la carga en el eje o el frenado a contracorriente. Entre los segundos se incluyen, por ej., el cortocircuito y los microcortes. Se establecerán las adecuadas condiciones de contorno que permitan la resolución del problema planteado. En función del tiempo requerido y de las dificultades que puedan encontrarse, se procederá también, en su caso, a la simulación del comportamiento del motor en el caso industrial de barras rotóricas rotas y su posible detección mediante métodos no invasivos (medida de las corrientes en el estator y su análisis aplicando transformadas tiempo-frecuencia).Bonet Jara, J. (2018). Desarrollo de un programa para la determinación del régimen dinámico de motores de jaula de ardilla. Aplicación al análisis de los transitorios industriales usuales y a los provocados por averías. http://hdl.handle.net/10251/107986TFG

Proyecto estructural de edificio industrial de 2200m2 situado en Pinoso, dedicado a producción y embotellado de vino

[ES] El objeto de este Trabajo Final de Grado es el cálculo estructural de una nave industrial, a partir de un proceso productivo determinado. El proceso productivo elegido para dicha nave es el relacionado con la industria vitivinícola, en concreto con el proceso de elaboración del vino previo a su maduración en barrica, y el proceso de embotellado para su posterior venta. El edificio dispone de una superficie construida de 2200m2 y se encuentra ubicado en el polígono 20, parcela 113 Alfaqui, a la altura del km‐13 de la CV‐836 en el término municipal de la localidad de Pinoso, Alicante.Bonet Jara, J. (2016). Proyecto estructural de edificio industrial de 2200m2 situado en Pinoso, dedicado a producción y embotellado de vino. http://hdl.handle.net/10251/65950

Comprehensive Analysis of Principal Slot Harmonics as Reliable Indicators for Early Detection of Inter-Turn Faults in Induction Motors of Deep-Well Submersible Pumps

2023 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Early detection of interturn faults is one of the most important issues in electrical machines, as the fault severity evolves very fast to a catastrophic failure due to the high thermal stress. However, as this article shows, in submersible induction motors for deep-well pumps, it evolves slower. These motors are highly water-cooled, which significantly reduces the thermal stress caused by the fault, increasing the possibility of early detection. Among fault detection methods, only those based on line current/voltage measurements can be used, as motors are at great depths. This article investigates the principal slot harmonics as reliable indicators for early detection of interturn faults in this application. To this end, a comprehensive analysis is conducted using finite-element analysis where the behavior of these harmonics is studied under different fault severities, both alone and coexisting with other asymmetries, such as unbalanced voltages, eccentricity, or rotor faults. The findings are used to develop a reliable diagnostic scheme based on the monitoring of the most fault-sensitive harmonics along with the voltage and current unbalance indexes. Finally, the scheme is applied, for the first time, in the context of continuous monitoring of a 230-HP induction motor showing its efficacy.This work was supported in part by the Universitat Politecnica de Valencia and in part by the Spanish Ministry of Science, Innovation and Universities under Grant FPU19/02698.Bonet-Jara, J.; Pons Llinares, J.; Gyftakis, KN. (2023). Comprehensive Analysis of Principal Slot Harmonics as Reliable Indicators for Early Detection of Inter-Turn Faults in Induction Motors of Deep-Well Submersible Pumps. IEEE Transactions on Industrial Electronics. 70(11):11692-11702. https://doi.org/10.1109/TIE.2022.32313331169211702701

Sensorless Speed Estimation for the Diagnosis of Induction Motors via MCSA. Review and Commercial Devices Analysis

[EN] Sensorless speed estimation has been extensively studied for its use in control schemes. Nevertheless, it is also a key step when applying Motor Current Signature Analysis to induction motor diagnosis: accurate speed estimation is vital to locate fault harmonics, and prevent false positives and false negatives, as shown at the beginning of the paper through a real industrial case. Unfortunately, existing sensorless speed estimation techniques either do not provide enough precision for this purpose or have limited applicability. Currently, this is preventing Industry 4.0 from having a precise and automatic system to monitor the motor condition. Despite its importance, there is no research published reviewing this topic. To fill this gap, this paper investigates, from both theoretical background and an industrial application perspective, the reasons behind these problems. Therefore, the families of sensorless speed estimation techniques, mainly conceived for sensorless control, are here reviewed and thoroughly analyzed from the perspective of their use for diagnosis. Moreover, the algorithms implemented in the two leading commercial diagnostic devices are analyzed using real examples from a database of industrial measurements belonging to 79 induction motors. The analysis and discussion through the paper are synthesized to summarize the lacks and weaknesses of the industry application of these methods, which helps to highlight the open problems, challenges and research prospects, showing the direction in which research efforts have to be made to solve this important problem.This work was supported by the Universitat Politecnica de Valencia and the Spanish Ministry of Science, Innovation and Universities [FPU19/02698].Bonet-Jara, J.; Quijano-Lopez, A.; Morinigo-Sotelo, D.; Pons Llinares, J. (2021). Sensorless Speed Estimation for the Diagnosis of Induction Motors via MCSA. Review and Commercial Devices Analysis. Sensors. 21(15):1-35. https://doi.org/10.3390/s21155037135211

End-Ring Wear in Deep-Well Submersible Motor Pumps

(c) 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works[EN] Wear of end ring is to date an unreported and uninvestigated failure that very frequently takes place in deep-well submersible motor pumps. This article first analyses the particularities of these induction motors, especially their unusual rotor manufacturing process. Failure mechanism related to the end-ring wear is described, showing several examples of damaged rotors in a motor repair shop. Then, the difficulties of its diagnosis through conventional rotor asymmetry indicators are described, caused by the subtlety of this fault and the very easy appearance of false negatives. The end-ring wear detection through a multicomponent approach is researched through simulation, laboratory results, and the diagnosis of two-field motors showing that new fault alarm levels need to be defined. To perform this last step and for the first time in the technical literature, two induction motors working in a deep borehole have been continuously monitored (one measure every six operating hours) for almost one year.This work was supported in part by the Universitat Politècnica de València and in part by the Spanish Ministry of Science, Innovation and Universities under Grant FPU19/02698Bonet-Jara, J.; Morinigo-Sotelo, D.; Duque-Perez, O.; Serrano Iribarnegaray, L.; Pons Llinares, J. (2022). End-Ring Wear in Deep-Well Submersible Motor Pumps. IEEE Transactions on Industry Applications. 58(4):4522-4531. https://doi.org/10.1109/TIA.2022.31668764522453158