Fault Detection of Circulation Pumps on the Basis of Motor Current Evaluation

2021 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 work. https://doi.org/10.1109/TIA.2021.3085697[EN] Motor current signature analysis (MCSA) for fault detection has found widespread application, especially for induction motors (IM). The basis of MCSA is the evaluation of a motor¿s current. This analysis is now also used for other motor types and can be used to detect faults of the coupled load. The purpose of this paper is to examine whether MCSA can be used to detect faults in a wet-rotor pump. A total of three faults are examined. The results show that, compared to a healthy pump, all faults could be detected. However, a detailed analysis of frequency components has to be carried out to differentiate the faults. A circulation pump with a maximum power consumption of 1.1 kW was used as the test item.This work was supported in part by the German Federal Ministry for Economic Affairs and Energy within the framework "Entwicklung optimierter Regelungen hydraulischer Systeme in der Gebaudetechnik zur Steigerung der Energieeffizienz von Heizungs-und Klimatisierungssystemen" under Grant 03ET1613B.Becker, V.; Schwamm, T.; Urschel, S.; Antonino-Daviu, J. (2021). Fault Detection of Circulation Pumps on the Basis of Motor Current Evaluation. IEEE Transactions on Industry Applications. 57(5):4617-4624. https://doi.org/10.1109/TIA.2021.30856974617462457

Emerging Converter Topologies and Control for Grid Connected Photovoltaic Systems

Continuous cost reduction of photovoltaic (PV) systems and the rise of power auctions resulted in the establishment of PV power not only as a green energy source but also as a cost-effective solution to the electricity generation market. Various commercial solutions for grid-connected PV systems are available at any power level, ranging from multi-megawatt utility-scale solar farms to sub-kilowatt residential PV installations. Compared to utility-scale systems, the feasibility of small-scale residential PV installations is still limited by existing technologies that have not yet properly address issues like operation in weak grids, opaque and partial shading, etc. New market drivers such as warranty improvement to match the PV module lifespan, operation voltage range extension for application flexibility, and embedded energy storage for load shifting have again put small-scale PV systems in the spotlight. This Special Issue collects the latest developments in the field of power electronic converter topologies, control, design, and optimization for better energy yield, power conversion efficiency, reliability, and longer lifetime of the small-scale PV systems. This Special Issue will serve as a reference and update for academics, researchers, and practicing engineers to inspire new research and developments that pave the way for next-generation PV systems for residential and small commercial applications

Energy management strategies based on fuzzy logic control for grid-tied domestic electro-thermal microgrid

The environmental and economic benefits related to the reduction of both carbon dioxide emission and transmission losses have made distributed renewable generation systems became a competitive solution for future power systems. In this context, Microgrids (MG) are considered as the key building blocks of smart grids and have aroused great attention in the last decade for their potential and the impact they may have in the coming future. The MG concept has captured great attention in the last years since it can be considered one of the most suitable alternatives for integration of distributed generation units in the utility grid. However, this integration involves some challenges to deal with especially when penetration of Renewable Energy Sources (RES) into the distribution network is increased. Therefore, an effective Energy Management System (EMS) is required to ensure optimal energy utilization within the MG, consequently, facilitating both the grid integration and operator control. In this regard, the EMS strategy design depends on the application, MG power architecture, and the power management capability of the MG elements. This dissertation research focuses on the design of different EMS strategies based on Fuzzy Logic Control (FLC) for a residential grid-connected electro-thermal MG including renewable power generation (i.e. photovoltaic and wind turbine generators) and storage capability (i.e. battery bank and water storage tank). The main goal of the FLC-based EMS strategies is to minimize the grid power fluctuations while keeping the battery State-of-Charge (SOC) within secure limits. In order to accomplish this goal, the controller design parameters, such as membership functions and rule-base, of the FLC-based EMS strategies, are adjusted to optimize a pre-defined set of quality criteria of the MG behavior. The analysis and design of the FLC-based EMS strategies for electrical and electro-thermal MG power architectures are developed considering two different scenarios. A first scenario where the MG power forecasting is not provided and a second scenario where the forecast of generation power and load demand are considered. A comparison with the different EMS strategies is presented in simulation level, whereas the features of the enhanced FLC-based EMS strategies are experimentally tested on a real residential microgrid implemented at the Public University of Navarre (UPNa)Este estudio presenta el diseño de diferentes estrategias de gestión energética basadas en un controlador difuso para una microrred electro-térmica residencial conectada a la red eléctrica compuesta por generadores de energía renovable (solar y eólico) y elementos de almacenamiento de energía (banco de baterías y tanque de almacenamiento de agua). El objetivo principal de las estrategias de gestión es reducir los picos y fluctuaciones de potencia en el perfil de potencia intercambiado con la red eléctrica y preservar la vida útil del sistema de almacenamiento. Se presenta una revisión del estado del arte de estudios anteriores que buscan este objetivo. Se muestra el análisis de dos arquitecturas de microrred. La primera arquitectura consiste en una microrred eléctrica compuesta fuentes de energía renovables, sistema de almacenamiento de energía y el consumo eléctrico de una vivienda. La segunda arquitectura consiste en una microrred electro-térmica que contiene los elementos de la microrred eléctrica e incluye adicionalmente generadores térmicos y el consumo térmico de la vivienda. Con el objetivo de medir la eficiencia de las diferentes estrategias de gestión, se presenta un conjunto de criterios de evaluación que analizan la calidad del perfil de potencia intercambiado con la red eléctrica obtenido mediante las diferentes estrategias de gestión energética. Estos criterios de calidad son utilizados adicionalmente para la optimización de parámetros de los controladores difusos, lo cual se realiza mediante un proceso de aprendizaje fuera de línea que considera los datos históricos del comportamiento de la microrred. La comparación entre las diferentes estrategias de gestión energética se realiza mediante simulación, utilizando los datos reales de generación y consumo adquiridos en la Universidad Pública de Navarra durante el período comprendido entre Julio 2013 y Julio 2014. El diseño de las estrategias de gestión energética para la arquitectura de microrred eléctrica supone dos posibles escenarios, el primer escenario no considera la previsión de consumo y generación de la microrred, y el segundo escenario si considera esta previsión. Las prestaciones de las estrategias basadas en control difuso para cada uno de estos escenarios son validadas experimentalmente en condiciones reales en la microrred de la Universidad Pública de Navarra. Finalmente, se presenta el análisis de las estrategias de gestión basadas en control difuso empleadas a la arquitectura de microrred electro-térmica. La comparación, mediante simulación, con otras estrategias de gestión aplicadas a la misma arquitectura ha demostrado el correcto desempeño de las estrategias desarrolladas basadas en control difuso.Postprint (published version

Hybrid Energy Storage Implementation in DC and AC Power System for Efficiency, Power Quality and Reliability Improvements

Battery storage devices have been widely utilized for different applications. However, for high power applications, battery storage systems come with several challenges, such as the thermal issue, low power density, low life span and high cost. Compared with batteries, supercapacitors have a lower energy density but their power density is very high, and they offer higher cyclic life and efficiency even during fast charge and discharge processes. In this dissertation, new techniques for the control and energy management of the hybrid battery-supercapacitor storage system are developed to improve the performance of the system in terms of efficiency, power quality and reliability. To evaluate the findings of this dissertation, a laboratory-scale DC microgrid system is designed and implemented. The developed microgrid utilizes a hybrid lead-acid battery and supercapacitor energy storage system and is loaded under various grid conditions. The developed microgrid has also real-time monitoring, control and energy management capabilities. A new control scheme and real-time energy management algorithm for an actively controlled hybrid DC microgrid is developed to reduce the adverse impacts of pulsed power loads. The developed control scheme is an adaptive current-voltage controller that is based on the moving average measurement technique and an adaptive proportional compensator. Unlike conventional energy control methods, the developed controller has the advantages of controlling both current and voltage of the system. This development is experimentally tested and verified. The results show significant improvements achieved in terms of enhancing the system efficiency, reducing the AC grid voltage drop and mitigating frequency fluctuation. Moreover, a novel event-based protection scheme for a multi-terminal DC power system has been developed and evaluated. In this technique, fault identification and classifications are performed based on the current derivative method and employing an artificial inductive line impedance. The developed scheme does not require high speed communication and synchronization and it transfers much less data when compared with the traditional method such as the differential protection approach. Moreover, this scheme utilizes less measurement equipment since only the DC bus data is required

Field data collection for implementation of Supercapacitor Assisted LED Lighting (SCALED)

With the increasing impact of global warming, climate change is becoming the biggest threat for all life on our planet. The conventional way of generating electricity from the burning of fossil fuels releases significant amounts of carbon dioxide to the atmosphere, which contributes to the rise in the earth’s temperature. Moreover, fossil fuels are being consumed very rapidly and we now have limited resources, which need to be monitored to face future energy demands. The development of renewable energy sources, such as solar power, is a rapidly growing technology. With the extensive research and investment in this industry at present, in the near future solar power will be one of our leading renewable energy sources. Furthermore, as solar panels directly produce direct current (DC), they can be directly tied to a DC microgrid without requiring any power converter, thereby minimizing losses and increasing efficiency. The supercapacitor assisted light emitting diode (SCALED) converter is one of the new circuit techniques under development for low voltage light emitting diode (LED) systems at the University of Waikato. In this circuit, an LED is connected in series with the supercapacitor bank forming part of a resistor-capacitor (RC) charging loop. This is to avoid energy losses in the RC charging loop, which can create, in the worst case, a 50% loss. As the commonly used 12 V LEDs are internally DC operated devices, SCALED will be applicable in DC microgrids, which are the emerging technology in low voltage distribution systems. The groundwork for this project requires various solar-related field data collection and simulations for the successful implementation of this innovative technique. Unlike a conventional power supply, solar power output directly depends on the solar irradiance level, which is very unpredictable. Given the unique behaviour of solar panel output, starting with a near constant current behaviour and changing over to a practical voltage source with an approximately constant array resistance, combining a supercapacitor bank and an LED lamp will be a challenge in developing the SCALED topology. In addition, proper field measurements and analysis of these characteristics are essential to develop more efficient and reliable SCALED circuits for DC microgrid applications

Analysis and Design of High Voltage Gain Three-Elements Resonant Soft-Switching Current-fed DC/DC Converters

Transportation electrification and distributed generation are proven effective strategies to counter climate change. Modern generation and transportation aim to bring down the carbon footprint by transforming the fossil fuel-driven society with alternate energy sources and electric propulsion, respectively. However, harnessing energy from renewable sources is not straight forward but demands a suitable power electronic interface. Similarly, electric transportation propulsion system demands for specific power conversion stages. These power electronic conversion systems include dc-dc converter and dc-ac inverter. Cost, efficiency, power density, and weight are the major requirements of these converters. To obtain these merits, high-frequency soft-switching converters are selected and designed. Resonant converters with a suitable resonance have been usually explored for voltage-fed switching converters to obtain soft-switching of the semiconductor devices at high-frequency. However, owing to the high voltage gain requirements of the solar/fuel cells/batteries, this thesis explores current-fed topologies with different resonant circuits with natural voltage gain. In traditional voltage-fed resonant converters, it is observed that the converter characteristics can be fine-tuned to design the requirements by proper selection of resonant tank. In addition, the resonant tank can integrate the transformer non-idealities and circuit/device parasitic in circuit operation thereby suppressing the consequent voltage spikes across the semiconductor devices. Since voltage-fed converters is fundamentally not suitable for high voltage gain and low voltage applications, this thesis attempts to improve current-fed dc/dc converter characteristics with resonant tanks. In this thesis, a current-fed load resonant DC/DC converter topology is proposed whose characteristics are tuneable with the adopted resonant tank. Further, this thesis proposes a simple technique to ease and improve accuracy of the Fundamental Harmonic Analysis (FHA), which would have been complex otherwise due to capacitive termination of proposed converter. Initially, the characteristics of the proposed converter topology with a parallel resonance derived LCC-T resonant tank is studied to implement zero voltage switching (ZVS) and zero current switching (ZCS) of the semiconductor devices. Three-phase topology of the same has been investigated and analysed. Following the study and a need to further improve the characteristics of resonant dc/dc converter, a series resonance based LCL resonant converter, a dual of the parallel resonance tank is studied and analysed. The load resonant converters are redeemed for integration of PV/fuel cells. Further, for high power applications, suitability of load resonant converters is verified by adopting resonant tank in three-phase topology. Proof-of-concept hardware prototypes are designed and developed in the laboratory to demonstrate the performance and the merits of the proposed soft-switching resonant converter topologies as well as to prove the proposed theory and the claims

Social, Private, and Trusted Wearable Technology under Cloud-Aided Intermittent Wireless Connectivity

There has been an unprecedented increase in the use of smart devices globally, together with novel forms of communication, computing, and control technologies that have paved the way for a new category of devices, known as high-end wearables. While massive deployments of these objects may improve the lives of people, unauthorized access to the said private equipment and its connectivity is potentially dangerous. Hence, communication enablers together with highly-secure human authentication mechanisms have to be designed.In addition, it is important to understand how human beings, as the primary users, interact with wearable devices on a day-to-day basis; usage should be comfortable, seamless, user-friendly, and mindful of urban dynamics. Usually the connectivity between wearables and the cloud is executed through the user’s more power independent gateway: this will usually be a smartphone, which may have potentially unreliable infrastructure connectivity. In response to these unique challenges, this thesis advocates for the adoption of direct, secure, proximity-based communication enablers enhanced with multi-factor authentication (hereafter refereed to MFA) that can integrate/interact with wearable technology. Their intelligent combination together with the connection establishment automation relying on the device/user social relations would allow to reliably grant or deny access in cases of both stable and intermittent connectivity to the trusted authority running in the cloud.The introduction will list the main communication paradigms, applications, conventional network architectures, and any relevant wearable-specific challenges. Next, the work examines the improved architecture and security enablers for clusterization between wearable gateways with a proximity-based communication as a baseline. Relying on this architecture, the author then elaborates on the social ties potentially overlaying the direct connectivity management in cases of both reliable and unreliable connection to the trusted cloud. The author discusses that social-aware cooperation and trust relations between users and/or the devices themselves are beneficial for the architecture under proposal. Next, the author introduces a protocol suite that enables temporary delegation of personal device use dependent on different connectivity conditions to the cloud.After these discussions, the wearable technology is analyzed as a biometric and behavior data provider for enabling MFA. The conventional approaches of the authentication factor combination strategies are compared with the ‘intelligent’ method proposed further. The assessment finds significant advantages to the developed solution over existing ones.On the practical side, the performance evaluation of existing cryptographic primitives, as part of the experimental work, shows the possibility of developing the experimental methods further on modern wearable devices.In summary, the set of enablers developed here for wearable technology connectivity is aimed at enriching people’s everyday lives in a secure and usable way, in cases when communication to the cloud is not consistently available

Покращення показників якості технологічного процесу управління тяговим електроприводом рульової системи літака

Представлена високоефективна система електричного руління (СЕР) як сучасне рішення для вдосконалення наземних операцій сучасних літальних апаратів, які звичайно працюють завдяки основним двигунам. Представлена СЕР приводиться в дію електродвигунами, інтегрованими в головну стійку шасі найсучаснішого комерційного літака середнього розміру, і живиться від додаткового джерела енергії. Таким чином, пропонована система може працювати автономно від будь-якого внутрішнього джерела літака, тобто допоміжного енергоблоку або йому аналогічного. В якості силового агрегату вибрано тяговий електропривод на основі СДПМ з векторним керуванням, на основі тестового моделювання доведено доцільність його використання у складі СЕР. Досліджено систему на основі профілів руління на зліт і посадку, виявлено ефективність її використання в якості засобу руління літаком. Досліджено виключення зовнішніх впливів та зміни параметрів електромеханічної системи колеса з пружним пневматиком, який полягає в побудові системи управління із адаптивним нечітким регулятором. Результати моделювання динамічних процесів електромеханічної системи, що містить пружні ланки, в умовах параметричних збурень підтвердили робастну стабілізацію динамічних показників якості управління на основі законів нечіткої логіки.A highly efficient electric taxi system (ETS) as a modern solution for improving the ground operations of modern aircraft, which are usually powered by main engines is presented. Presented ETS driven by electric motors integrated into the main landing gear of the most modern commercial aircraft of medium size, and is powered by more energy source. Thus, the proposed system can operate autonomously from any internal energy source of the aircraft, i.e. auxiliary power unit or similar. The traction electric drive on the basis of PMSM with field-oriented control is chosen as the power unit, on the basis of test modeling the expediency of its use as a part of ETS is proved. The system on the basis of taxiing profiles for takeoff and landing is investigated, the efficiency of its replacement as a means of taxiing aircraft is revealed. The exclusion of external influences and parameters changes of the electromechanical wheel system with an elastic tire, which consists in the construction of a control system with an adaptive fuzzy controller are investigated. The results of modeling the dynamic processes of an electromechanical system containing elastic links under conditions of parametric perturbations confirmed the robust stabilization of dynamic control quality indicators based on the laws of fuzzy logic.Представлена высокоэффективная система электрического руления (СЭР) как современное решение для совершенствования наземных операций современных летательных аппаратов, которые обычно работают благодаря основным двигателям. Представленная СЭР приводится в действие электродвигателями, интегрированными в главную стойку шасси современного коммерческого самолета среднего размера, и питается от дополнительного источника энергии. Таким образом, предлагаемая система может работать автономно от любого внутреннего источника самолета, то есть вспомогательного энергоблока или ему аналогичного. В качестве силового агрегата выбрано тяговый электропривод на основе СДПМ с векторным управлением, на основе тестового моделирования доказана целесообразность его использования в составе СЭР. Исследована система на основе профилей рулежки на взлет и посадку, выявлена эффективность ее использования в качестве средства руления самолетом. Исследовано исключения внешних воздействий и изменения параметров электромеханической системы колеса с упругим пневматиком, который заключается в построении системы управления с адаптивным нечетким регулятором. Результаты моделирования динамических процессов электромеханической системы, содержащей упругие звенья, в условиях параметрических возмущений подтвердили робастную стабилизацию динамических показателей качества управления на основе законов нечеткой логики

Machines à commutation de flux à grand nombre de phases : modèles comportementaux en mode dégradé et élaboration d’une stratégie de commande en vue de l’amélioration de la tolérance aux pannes

In this thesis, we are interested in the study of a five-phase flux switching permanent magnet machine (five-phase FSPM machine) behavior in healthy and faulty mode. First, a comparison of electromagnetic performances between this machine and an equivalent three-phase machine is carried out. These performances are calculated by a Finite Element (FE 2D) model and validated by experiments. Results showed the five-phase machine contribution with a higher torque density, lower torque ripples, lower short-circuit current and ability to tolerate phases faults. The study of open-circuit tolerance is then developed for this five-phase FSPM. The behavior of the machine (the average torque, torque ripples, copper losses and the current in the neutral) in the case of open-circuit on a single and two adjacent and non-adjacent phases is presented. Then reconfiguration methods to improve the operation are proposed including a minimum reconfiguration allowing to end up with a feeding equivalent to that of a three-phase or a four-phase machine, an analytical calculation of optimal currents to cancel both the neutral current and torque ripples while ensuring the average torque, and finally a reconfiguration performed by a genetic optimization algorithm which is a non-deterministic algorithm multi-objective functions and multi-constraints. In this context, various combinations of different objectives and constraints are proposed and optimal currents are injected into the 2D FE model of the machine to see if performances have been improved. The analytical model of the torque used in the optimization algorithm is then revised to take into account the influence of the degraded mode. Different solutions of Pareto front are analyzed and electromagnetic performances are improved. This is verified by FE 2D calculations and followed by experimental validation. Faults impact on the radial magnetic forces is also analyzed. In the second part of this work, the study of the five-phase FSPM machine tolerance to short-circuit faults is performed. First steps of the faults isolation are proposed. Thereafter, short-circuit currents, taking into account the reluctance machine impact, are calculated analytically and their effects on machine performances are analyzed. Reconfigurations are also calculated by the genetic algorithm optimization and new references currents improved the degraded mode operation. All results are validated by the FE 2D calculation and experimentally. In conclusion, comparisons between fault-tolerance to phases openings and short-circuits of the five-phase FSPM machine are performed. Results led to conclude regarding the operation of this machine in healthy and degraded modes with and without correction. Analytical, numerical and experimental results showed good efficiency of the proposed control to improve fault-tolerance to phases openings and short-circuits.Dans cette thèse, nous nous sommes intéressés à l'étude des modèles comportementaux en mode dégradé des machines pentaphasées à commutation de flux (MCF pentaphasée). Tout d'abord, une comparaison des performances électromagnétiques de cette machine à une machine triphasée équivalente est tout d'abord effectuée. Ces performances sont calculées par la méthode des Eléments Finis (EF 2D) et validées expérimentalement. Les résultats ont montré l'apport de la machine pentaphasée avec un couple massique plus élevé, une ondulation de couple plus faible, un courant de court-circuit plus faible et sa capacité à tolérer des défauts de phases. L'étude de la tolérance aux ouvertures de phases est alors élaborée pour cette MCF pentaphasée. Le comportement de la machine en cas d'ouvertures de phases (du point de vue du couple moyen, de l'ondulation de couple, des pertes Joule et du courant dans le neutre) est présenté. Ensuite, des méthodes de reconfiguration en vue d'améliorer le fonctionnement sont proposées dont une reconfiguration minimale permettant de se retrouver avec une alimentation équivalente à celle d'une machine tétraphasée ou triphasée, un calcul analytique des courants optimaux permettant d'annuler à la fois le courant du neutre et l'ondulation du couple tout en assurant le couple moyen, et finalement une reconfiguration assurée par un algorithme génétique d'optimisation qui est un algorithme non-déterministe multi-objectifs et multi-contraintes. Diverses combinaisons des différents objectifs et contraintes sont, dans ce cadre, effectuées et les courants optimaux sont injectés dans le modèle EF 2D de la machine pour vérifier si les performances ont été améliorées. Le modèle analytique du couple pris en compte dans l'algorithme d'optimisation est alors révisé pour prendre en compte l'influence du mode dégradé. Les différentes solutions du front de Pareto sont analysées et les performances électromagnétiques sont bien améliorées. Cela est vérifié par les calculs EF 2D et suivi d'une validation expérimentale. L'influence des défauts sur les forces magnétiques radiales est également analysée. Dans une seconde partie, l'étude de la tolérance de la machine pentaphasée à commutation de flux aux défauts de courts-circuits est effectuée. Les premières étapes d'isolation des défauts de courts-circuits sont proposées. Par la suite, les courants de courts-circuits, prenant en compte l'effet reluctant de la machine, sont calculés analytiquement et leurs effets sur les performances de la machine sont analysés. Les reconfigurations sont aussi calculées par l'algorithme génétique d'optimisation et les nouvelles références des courants permettent d'améliorer le fonctionnement en mode dégradé. Tous les résultats sont validés par la méthode des EF 2D et expérimentalement. En conclusion, des comparaisons entre la tolérance aux défauts d'ouvertures et de courts-circuits de la machine pentaphasée à commutation de flux sont effectuées et ont permis de conclure quant au fonctionnement de cette machine en modes sain et dégradé avec et sans correction. Les résultats analytiques, numériques et expérimentaux ont montré la bonne efficacité de la commande proposée pour l'amélioration de la tolérance aux défauts d'ouvertures et courts-circuits de phases