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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Design and implementation of an SPB converter for fault tolerant PMSynRel motor control

Apostolopoulos, Nikolaos January 2015 (has links)
The stacked polyphase bridges (SPB) converter topology is investigated in the presentthesis as a fault-tolerant choice for permanent-magnet synchronous reluctance (PMSyn-Rel) motor control. Integrated motor drive systems are studied as they offer great benefitsfor propulsion applications. Moreover, the importance of a modular topology, like theSPB, for an electric powertrain is discussed. The latter consists of a number of seriesconnected, 3-phase 2-level inverter submodules that supply separate sets of windings ina multi-star motor. The specifications of building a four-board SPB setup are examined,while the challenges of an active voltage balancing controller are analyzed. The designprocess is explained step-by-step and the final printed circuit boards (PCBs) are presented.Furthermore, the significance of low electromagnetic interference design for a converterthat requires high speed communication is highlighted. Finally, the prototype is testedthoroughly and the expected fault-tolerant capabilities are validated on a PMSynRel motor. / I detta examensarbete unders¨ok SPB-omriktartopologin (stacked polyphase bridges converter)i termer av ett feltolerant elektriskt drivsystem f¨or en permamentmagnetassisteradsynkron reluktansmaskin (PMSynRel). SPB-omriktaren best°ar av ett antal seriekoppladetrefasomriktare av tv°aniv°atyp som, var och en, f¨orser effekt till en trefaslindningtillh¨orande en modul¨ar elmaskin av multifastyp. Specifikation, design och konstruktion aven SPB-omriktare med fyra seriekopplade moduler studeras. Designproceduren presenterasi en steg-f¨or-steg-process och de tillverkade kretskorten presenteras utf¨orligt. Kommunikationenmellan de olika kretskorten unders¨oks med s¨arskild tonvikt p°a l°ag elektromagnetiskinterferens vilket ¨ar n¨odv¨andigt om h¨og kommunikationshastighet skall kunnauppn°as. Den f¨ardigst¨allda prototypen har utv¨arderats experimentellt och kapaciteten f¨orfeltolerans har demonstrerats vid drift av en PMSynRel-maskin utrustad med en multifaslindning.
402

Design and Analysis of a Fractional-Slot Concentrated-Wound Permanent-Magnet-Assisted Synchronous Reluctance Machine / Konstruktion och analys av en permanent magnetiserade synkronreluktans motor med koncentrerad lindning

Carvajal Almendros, Celia January 2015 (has links)
The growing need for simpler and cheaper manufacturing process has led to the research into fractional-slot concentrated-wound (FSCW) motors. This concept has been widely investigated for surface-mounted permanent magnet (SMPM) machines. This thesis studies the same concept applied for synchronous reluctance machines (SynRM). In this thesis, a FSCW, 15 kW, 4-pole, Permanent-Magnet-Assisted Synchronous Reluctance Machine (PMaSynRM) is designed and optimized using finite element method (FEM) based simulations for a set of given technical specifications. Initially, the existing synchronous machine topologies are investigated and later two novel motor designs are introduced and optimized, namely, a FSCW-SynRM and a FSCW-PMaSynRM with ferrite magnets. Moreover, the influence of replacing ferrite material with Neodymium Iron Boron (NdFeB) in the FSCWPMaSynRM is analyzed. Detailed investigations are performed in order to compare the impact of material at different temperatures. Variation of the torque-speed capabilities with temperature and a safe operating temperature range where the magnets are not demagnetized are identified. The variation of overload capability with temperature is also studied. Finally, a comparison between the new proposed designs and other existing standard design topologies is performed. It was found that FSCW-SynRM present lower efficiency, power factor and higher torque ripple than DW-SynRM. However when ferrite magnets are inserted in FSCW-PMaSynRM the efficiency, power factor and the flux-weakening capability exceed the values of the DW-SynRM. Moreover, by using NdFeB instead of ferrite in FSCW-PMaSynRM, the torque ripple, the fluxweakening capability and the overload capability improve and a wider safe temperature range for no demagnetization is achievable. Finally, it is found that DW-PMaSynRM with ferrite presents the same efficiency level as FSCW-PMaSynRM with ferrite, but higher power factor and lower torque ripple. However FSCW-PMaSynRM with ferrite have other advantages, such as shorter end-winding length, good fault-tolerant capability and simpler and cheaper manufacturing process. / Det växande behovet av enklare och billigare tillverkningsprocesser har lett till att den senaste forskningen om elektriska maskiner har fokuserats till maskiner med koncentrerade lindningar (FSCW). Detta koncept har i stor utsträckning undersökts för synkronmaskiner med ytmonterade permanentmagneter (SMPM). Detta projekt studerar samma lindning koncept, tillämpat på synkrona reluktansmaskiner (SynRM). I denna avhandling är en 15 kW, 4-polig, SynRM med FSCW och permanentmagneter (PMaSynRM) utformad och optimerad med användandet av finita elementmetoden (FEM). Simuleringar för en uppsättning givna, tekniska specifikationer har genomförts. Inledningsvis undersöks den befintliga synkronreluktansmaskinen med distribuerad lindning och senare presenteras och optimeras två nya motorkonstruktioner: en FSCW-SynRM respektive en FSCW-PMaSynRM med ferritmagneter. Vidare analyseras påverkan av att ersätta ferritmaterial med neodym-järn-bor (NdFeB) i FSCW-PMaSynRM. Detaljerade undersökningar genomförs för att jämföra effekten av materialen vid olika temperaturer. Variationen av maximal vridmomentet som funktion av hastighet vid olika temperaturer identifierar ett säkert driftstemperaturintervall där magneterna inte avmagnetiseras. Även variationen i överbelastningskapacitet vid olika temperaturer studeras. Slutligen görs en jämförelse mellan den nya föreslagna designen och andra befintliga topologier. Resultaten visar att FSCW-SynRM har lägre effektivitet och effektfaktor, samt högre vridmomentsrippel än DW-SynRM. När ferritmagneter är införda i FSCW-PMaSynRM erhålls emellertid högre värden på effektivitet, effektfaktor och fältförsvagning än i DW-SynRM. Genom att använda NdFeB i stället för ferrit i FSCW-PMaSynRM förbättras dessutom vridmomentet, fältförsvagningskapaciteten och överbelastningskapaciteten, vilket ger ett bredare temperaturområde utan avmagnetisering. Slutligen visar DW-PMaSynRM med ferrit samma effektivitetsnivå som FSCW-PMaSynRM med ferrit, men med högre effektfaktor och lägre vridmomentsrippel. FSCW-PMaSynRM med ferrit har dock andra fördelar, såsom kortare härvänderna, god feltolerans samt enklare och billigare tillverkningsprocess.
403

Innovative twisting mechanism based on superconducting technology in a ring-spinning system

Hossain, Mahmud, Abdkader, Anwar, Cherif, Chokri, Sparing, Maria, Berger, Dietmar, Fuchs, Günter, Schultz, Ludwig 17 September 2019 (has links)
Twist plays an important role to impart tensile strength in yarn during the spinning process. In the most widely used ring-spinning machine for short staple yarn production, a combination of ring and traveler is used for inserting twist and winding the yarn on cops. The main limitation of this twisting mechanism is the friction between the ring and traveler, which generates heat at higher speed and limits the productivity. This limitation can be overcome by the implementation of a magnetic bearing system based on superconducting technology, which replaces completely the existing ring/traveler system of the ring-spinning machine. This superconducting magnet bearing consists of a circular superconductor and permanent magnet ring. After cooling the superconductor below its transition temperature, the permanent magnet ring levitates and is free to rotate above the superconductor ring according to the principles of superconducting levitation and pinning. Thus the superconducting magnetic bearing (SMB) ensures a friction-free operation during spinning and allows one to increase spindle speed and productivity drastically. The yarn properties using the SMB system have also been investigated and they remain nearly identical to those of conventional ring yarns.
404

A Semi-Analytical Approach to Noise and Vibration Performance Optimization in Electric Machines

Das, Shuvajit 14 November 2021 (has links)
No description available.
405

Magnetic Moment Characterization for Small Satellites

Sans Monguiló, Alejandro January 2021 (has links)
Small satellites are gaining popularity in a wide range of applications where attitude systems require high precision performance. One of the main sources of errors, in case of magnetic attitude control systems, is the residual magnetic moment (RMM) of the spacecraft. To keep the RMM low and stable, mitigation methods shall be applied based on the satellite’s magnetic dipole moment (MDM) characterization, which shall be measured accurately. For small satellites, the most common technique involves the generation of a field-free region for the magnetic measurements using a test bed. The test bed measurement setup is normally mechanical, where measurements from the device under test (DUT) are very tedious. Optical magnetic test beds (OMTB) are being developed for MDM characterization providing simpler set ups and faster measurements than mechanical test beds. In this work, accuracy of OMTB of Aalto University has been evaluated by measuring three permanent magnets in two configurations. The measurements show a relationship between the estimation accuracy and the DUT’s marker area seen by the camera. Moreover, it was observed that the field-free region generated by Helmholtz coil cage can generate false data points. Based on these observations, the detection of the marker’s positions have been evaluated using the view area (VA) and the pointing angle (PA). The analysis shows that there is a consistent pattern depending on the combination of the VA and PA. Hence, the method of data acquisition was improved in order to prioritize the markers which position allow better accuracy. The achieved improvement of MDM estimation results is 2 %, and the test bed’s overall error evaluated is a 13 % in MDM position estimation and 23 % in MDM magnitude estimation. The improved OMTB was used to characterize the MDM of four magnetic attitude coils of Foresail-1 satellite. The measurements results are consistent with design parameters, showing three dipole configuration in all coils with a MDM magnitude order of 10−2 A·m2. / Foresail-1
406

On magnetic amplifiers in aircraft applications

Austrin, Lars January 2007 (has links)
In the process of designing an electric power supply system for an aircraft, parameters like low weight and low losses are important. Reliability, robustness and low cost are other important factors. In the Saab Gripen aircraft, the design of the primary power supply of the electric flight control system was updated by exchanging a switching transistor regulator to a magnetic amplifier (magamp). By introducing a magamp design, weight was saved and a more reliable power supply system at a lower cost was achieved. In this particular case, with the power supply of the electric flight control system in the Saab Gripen fighter, advantage could be taken of a specific permanent magnet generator (PM-generator). The frequency of the generator offered the perfect conditions for a magamp controller. A key parameter in designing magnetic amplifiers (magamps) is low losses. New amorphous alloys offer new possibilities of the technique in designing magnetic amplifiers, because of their extremely low losses. The core losses are evaluated by studying the equations and diagrams specifying the power losses. The core losses are evaluated and compared with the copper losses in the process of optimizing low weight and low losses. For this an engineering tool is developed and demonstrated. Evaluations of the hysteresis characteristics for the magnetic alloys, as well as modeling and simulation of the core losses, are presented in this work. The modeling of the core losses includes hysteresis losses, eddy current losses and excess losses as well as copper losses. The losses are studied dynamically during realistic operational conditions. The model can be used for any generic analysis of hysteresis in magnetic circuits. Applications of magnetic amplifiers in aircrafts have been demonstrated to be a feasible alternative / QC 20101103
407

Current-based Techniques for Condition Monitoring of Pumps

Becker, Vincent 12 December 2022 (has links)
[ES] Las bombas hidráulicas son el núcleo de muchos procesos en la industria y el sector servicios. Conviene tener en cuenta que los motores eléctricos son responsables del 69% del consumo de energía eléctrica en la industria, siendo en torno a un 22% de motores utilizados para el accionamiento de bombas. Los fallos de estas bombas pueden provocar averías en el proceso y, por lo tanto, implican altos costes económicos para el operador de la planta. Además, un funcionamiento defectuoso de las bombas conlleva una reducción de la eficiencia energética de la planta. De forma habitual, se utilizan principalmente dos tipos de estrategias orientadas al mantenimiento de maquinaria. Una estrategia de mantenimiento (mantenimiento preventivo) consiste en la sustitución de las piezas desgastadas en un intervalo de tiempo fijo. Este tipo de estrategia presenta muchas desventajas asociadas a la escasa optimización en el uso de los recursos y al consiguiente impacto económico. Por otro lado, la estrategia basada en la condición del equipo (mantenimiento basado en la condición) liga el reemplazo de las piezas desgastadas al estado del equipo, el cual es monitorizado a través de señales adquiridas mediante sensores. Sin embargo, el uso de sensores tiene algunos inconvenientes, como costes de inversión adicionales, posibles problemas en el montaje del sensor y posibles fallos del mismo. El análisis de la señal de corriente no se ha utilizado de forma habitual en la práctica para evaluar el estado de la bomba, aunque en muchas aplicaciones se dispone de sensores de corriente ya instalados que se podrían utilizar a tal fin. Se ha demostrado que técnicas basadas en el análisis de la corriente resultan de gran utilidad para diagnosticar varios tipos de fallos en motores eléctricos. De hecho, el análisis de la firma de corriente del motor se utiliza hoy en día ampliamente en la industria, especialmente para el diagnóstico de fallos en motores de inducción. En la presente tesis, se evalúa la utilización de la técnica de análisis de corrientes para el diagnóstico de fallos típicos relacionados con las bombas en diferentes aplicaciones. Se investigan tres tipos de bombas diferentes: bombas en línea de rotor húmedo, bombas de rotor seco y bombas sumergibles. En la tesis se han adaptado diversas técnicas, previamente empleadas para la detección de fallos en motores, al diagnóstico de fallos en la propia bomba. Los resultados indican que fallos como obstrucción de la bomba, fisura del impulsor y desgaste de los cojinetes influyen especialmente en dos frecuencias del espectro de corriente, las cuales pueden utilizarse como base de estrategias de mantenimiento basadas en la condición. En concreto, en las bombas de rotor húmedo, estos dos indicadores de fallo varían sensiblemente en función del punto de carga hidráulica de la bomba. Con la ayuda de un método de extracción de características basado en la motor reference frame theory, se demuestra que las mencionadas frecuencias pueden analizarse en tiempo real en un entorno industrial. Además, se presentan directrices para la monitorización en la nube y se valida con la ayuda de ensayos de laboratorio. Adicionalmente, se demuestra que los fallos son también detectables al analizar la corriente de arranque mediante herramientas de descomposición tiempo-frecuencia. Este hito no se había abordado anteriormente en la literatura técnica del área en lo referente a la detección de fallos en bombas. En conclusión, los resultados de este trabajo demuestran que los métodos de diagnóstico basados en la corriente pueden detectar con éxito diversos tipos de fallo en bombas, lo cual constituye un punto de gran interés para las industrias que utilicen estos activos en sus procesos. / [CA] Les bombes hidràuliques són el nucli de molts processos en la indústria i en el sector dels serveis. Cal mencionar que els motors elèctrics són responsables del 69% del consum de la energia elèctrica en la indústria, sent al voltant del 22% dels motors utilitzats per l'accionament de bombes. Les fallades d'aquestes bombes poden causar avaries en els processos, i per tant, representen un alt cost econòmic per a l'operador de la planta. A més a més, un funcionament defectuós en les bombes representa una reducció de l'eficiència energètica de la planta. De manera habitual, s'utilitzen principalment dos tipus d'estratègies orientades al manteniment de la maquinària. Una estratègia de manteniment (manteniment preventiu) consisteix en la canvi de les peces desgastades en un interval fixe de temps. Aquest tipus d'estratègia presenta molts desavantatges associats a la reduïda optimització en el ús dels recursos i el seu impacte econòmic. D'altra banda, la estratègia basada en la condició dels equipaments (manteniment basat en la condició) enllaça la substitució de les peces desgastades al estat de l'equip, el qual es monitoritzat per mig de senyals adquirides per sensors. No obstant això, el ús de sensors té alguns inconvenients com costos d'inversió addicionals, possibles problemes al muntatge i possibles fallades. L'anàlisi dels senyals de corrent no s'utilitzen de manera habitual en la pràctica per avaluar l'estat de la bomba, encara que en moltes aplicacions, estos sensors es troben instal·lats i es podrien fer servir per a aquesta finalitat. Ha estat demostrat que les tècniques basades en l'anàlisi de la corrent són de gran utilitat per el diagnosi de diversos tipus de fallades en motors elèctrics. De fet, l'anàlisi de la firma de la corrent del motor s'utilitza àmpliament en l'indústria, especialment per el diagnosi de fallades en motors d'inducció. En la present tesi, s'avalua l'utilització de la tècnica d'anàlisi de corrents per el diagnosi de fallades típiques relacionades en bombes per a diferents aplicacions. Se investiguen tres tipus de bombes diferents: bombes en línia de rotor humit, bombes de rotor sec i bombes submergibles. En aquesta tesi se han adaptat diverses tècniques, prèviament utilitzades en el diagnosi de màquines elèctriques, per al diagnosi de la pròpia bomba. Els resultat indiquen que les fallades com obstrucció de la bomba, la fissura de l'impulsor i el desgast dels coixinets influeixen especialment en dos freqüències de l'espectre de la corrent, les quals es poden utilitzar com a base per a una estratègia de manteniment basada en la condició. Particularment, en les bombes de rotor humit, aquestos dos indicadors de fallada varíen sensiblement en funció del punt de càrrega hidràulica de la bomba. En l'ajuda de un mètode d'extracció de característiques basat en la "motor reference frame theory", es demostra que les mencionades freqüències es poden analitzar en temps real en un entorn industrial. A més a més, es presenten directrius per la monitorització en el núvol i es valida en l'ajuda de assajos en el laboratori. Addicionalment, es demostra que les fallades són també detectables quan s'analitza la corrent d'arrancada mitjançant ferramentes de descomposició temps-freqüència. Aquest fet no ha estat analitzat prèviament en cap tipus de literatura tècnica dins del camp de detecció de fallades en bombes. En conclusió, els resultats d'aquest treball demostren que els mètodes de diagnosi basats en la corrent poden detectar en èxit diversos tipus de fallades en bombes, el qual constitueix un punt d'interés per a l'indústria que utilitzen aquest tipus de actiu en els seus processos. / [EN] Pumps are the heart of many processes in industry and service sector. Electric motors are responsible for 69% of electric energy consumption in industry, with 22% of them being used for the operation of pumps. Pump faults can lead to process breakdowns and are thus related to high costs for the plant operator. Furthermore, faulty operation of pumps reduces the energy efficiency of the plant. In many cases, a time-based maintenance strategy is applied, which means that typical wear parts are replaced within defined time cycles, which comes with some drawbacks such as poor resource efficiency and high costs. Condition-based maintenance strategies - meaning that the replacement of parts is planned based on the condition of the pump - are often based on the evaluation of sensor signals like vibration or noise. However, the use of sensors also has some drawbacks, such as additional investment costs, frequent problems with the sensor mounting, and possible sensor faults. There is no widespread use of the current signal to make statements about the pump condition, although current sensors are installed in many applications anyway. As for motor fault diagnosis, different current-based techniques have demonstrated their function. Today, motor current signature analysis is used in industry, especially for the diagnosis of induction motors. In this thesis, the current-based diagnosis of typical pump-related faults in different applications is evaluated. In total, three different pump types are investigated: a wet-rotor pump, a dry-runner inline pump, and a submersible pump. The techniques used for motor fault detection are adapted for the diagnosis of pump-related faults. The results indicate that the faults clogging, impeller crack, and bearing wear, in particular, influence two frequencies in the current spectrum, which can be used as a basis for a condition-based maintenance strategy. Especially in wet-rotor pumps, these two fault indicators strongly vary depending on the hydraulic load point of the pump. With the help of a feature extraction method based on the adapted reference frame theory, this work demonstrates that the two frequencies can be analyzed in real time in a field environment. Furthermore, a concept for cloud monitoring is presented and validated with the help of a laboratory test. Additionally, it is demonstrated that the faults are visible if the starting current is evaluated in a time-frequency map, which has not been considered before in the literature on pump-related faults. In summary, the findings of this work indicate that current-based diagnosis methods can successfully detect typical faults in pumps, a fact that is of high interest for companies using these assets in their industrial processes. / Becker, V. (2022). Current-based Techniques for Condition Monitoring of Pumps [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/190630
408

Enhancing Servo System Performance : Robust Nonlinear Deadbeat Predictive Current Control for Permanent Magnet Synchronous Motors / Förbättring av prestanda för servo system : Robust ickelinjär deadbeat förutsägande strömkontroll för permanenta magnet synkronmotorer

Zhao, Xingyu January 2023 (has links)
The Permanent Magnet Synchronous Motor (PMSM, also known as the servo motor) is a crucial component within robotic servo systems. To optimally respond to the torque demands sent from the high-level motion controller, the PMSM current controller must track the reference with speed and precision. Nevertheless, the operation of servo motors could be compromised due to the nonlinearity of flux linkage and inaccuracies in parameters induced by unpredictable fluctuations in temperature. This Master’s thesis proposes a novel Robust Nonlinear Deadbeat Predictive Current Control (RN-DPCC) scheme to counter these challenges effectively. The nonlinear mappings between flux linkage and current on the dq-axis are established using polynomial fitting based on experimental data. Furthermore, the Nonlinear Deadbeat Predictive Current Control (N-DPCC) is derived using nonlinear feedforward. Meanwhile, Delayed Integral Action (DIA) is introduced as a robustness-enhancing measure for N-DPCC, thus evolving it into the Robust N-DPCC (RN-DPCC). Compared to conventional Integral Action (IA), DIA effectively curtails overshoot triggered by integral error and accelerates the current transient without incorporating additional tunable parameters. Numerical simulations that leverage the mathematical modeling of the converter and nonlinear PMSM are implemented using fundamental blocks in Simulink, which replicates the actual experimental setup employed within the Motor Control Lab at ABB Corporate Research. The effectiveness of employing nonlinear feedforward compensation is confirmed through a comparative analysis of the simulation results from N-DPCC and conventional Deadbeat Predictive Current Control (DPCC). The enhancements in transient response brought about by DIA are demonstrated through a comparison of RNDPCC and N-DPCC with IA. The robustness of RN-DPCC is demonstrated by comparing it with N-DPCC under conditions where parameter inaccuracies are present. / Den permanenta magnet-synkronmotorn (PMSM, även känd som servomotorn) är en avgörande komponent inom robotiserade servosystem. För att optimalt kunna reagera på momentkraven som skickas från högnivårörelsekontrollern måste PMSM-strömregulatorn följa referensen med hastighet och precision. Trots detta kan driften av servomotorer påverkas av ickelinjäriteter i flödeslänkningen och felaktigheter i parametrar som orsakas av oförutsägbara temperaturfluktuationer. Denna magisteravhandling föreslår en ny robust icke-linjär deadbeat-prediktiv strömreglering (RN-DPCC) för att effektivt hantera dessa utmaningar. De icke-linjära avbildningarna mellan flödeslänkning och ström på dq-axeln etableras med hjälp av polynomisk anpassning baserat på experimentella data. Dessutom härleds den ickelinjära deadbeat-prediktiva strömregleringen (N-DPCC) med hjälp av Ickelinjär feedforward. Samtidigt introduceras fördröjd integralåtgärd (DIA) som en robusthetsförbättrande åtgärd för N-DPCC, vilket förvandlar den till Robust N-DPCC (RN-DPCC). Jämfört med konventionell integralåtgärd (IA) minskar DIA effektivt överhäng som utlöses av integralfel och accelererar strömövergången utan att införa ytterligare justerbara parametrar. Numeriska simuleringar som utnyttjar den matematiska modelleringen av omvandlaren och den icke-linjära PMSM implementeras med hjälp av grundläggande block i Simulink, vilket återskapar den faktiska experimentella uppställningen som används i Motor Control Lab vid ABB Corporate Research. Effektiviteten i att använda icke-linjär framåtmatningskompensation bekräftas genom en jämförande analys av simulationsresultaten från N-DPCC och konventionell deadbeat-prediktiv strömreglering (DPCC). Förbättringarna i transientrespons som DIA medför demonstreras genom en jämförelse av RN-DPCC och NDPCC med IA. Robustheten hos RN-DPCC demonstreras genom att jämföra den med N-DPCC under förhållanden där parameterfel förekommer.
409

Modelling and Simulation of Interior Permanent Magnet Synchronous Machine and, Design Optimization Towards Transmission

Balaji, Sindhuja January 2022 (has links)
This report summarizes the thesis study carried out at Scania CV AB. The study presents design optimization of an interior permanent magnetic (IPM) synchronous machine. A parameterised Matlab tool was developed in order to serve the optimization routine. In this routine, multiple IPM geometries are dynamically generated and analyzed using the finite element method (FEM) software Flux 2D. Using the Secant method, algorithms to estimate the optimum current and control angle throughout the speed range both below and above base speed, were developed and integrated with the Matlab tool to perform design optimization towards the drive cycle. The genetic algorithm available in the Matlab’s global optimization toolbox has been utilised for the multi-objective optimization setup. / Denna rapport sammanfattar examensarbetet som genomförts på Scania CV AB. Studien presenterar en designoptimering av en permanentmagnetiserad (IPM) synkronmaskin. Ett parametriserat Matlab-verktyg för optimeringar utvecklades for att dynamiskt generera geometrier för att utföra simuleringar med hjälp av FEM-programvara (Flux2D®). Med hjälp av Sekant-metoden utvecklades och integrerades algoritmer för att estimera den optimala strömmen och styrvinkeln i hela varvtalssområdet, både under basvarvtal och i fältförsvagningsområdet. Med hjälp av Matlab-verktyget kunde sedan designoptimering för en given k¨orcykel utföras. Den genetiska algoritmen som finns tillgänglig i Matlabs globala optimeringsverktygslåda har använts för det multi-objektiva optimeringsprogrammet.
410

Design of a Switched Reluctance Motor for a Light Sport Aircraft Application

Abdollahi, Mohammad Ehsan January 2022 (has links)
With the rapid growth of air travel, concerns about the emissions of greenhouse gas emissions resulting from the air transportation sector are growing. Although the current battery technologies might not be adequate for all-electric regional aircraft, the energy density of the current battery technologies could be adequate to electrify light-sport aircraft used for training and recreation. Due to the nature of the propeller load and noise isolation of the cabin, switched reluctance motors can be an excellent candidate for the propulsion system of electrified light-sport aircraft. The proposed SRM is designed to replace a 70 kW permanent magnet synchronous motor used in the aerospace industry with similar volume constraints and operational requirements. In order to meet the high-power density requirements of this application, a design framework is proposed which includes several layers of the design process. The design objectifies are the average torque, torque ripple, and radial forces by integrating the control and geometry design into the proposed framework. A comprehensive design process is carried out with the proposed framework, and a detailed coil design process is performed. The rotor cut-outs are designed to reduce the weight of the motor. The thermal performance of the motor has been analyzed for the calculated motor losses and the cooling system constraints. / Thesis / Master of Applied Science (MASc)

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