The reluctance torque of switched reluctance motor could drive the rotor directly. Rotor doesn¡¦t need to be made from permanent magnet and the demagnetization and heat emission problems can be avoided. There are also a lot of advantages, such as the low cost, high efficiency, high stability and high hot emission, make it very attractive to the engineers and researchers. The dual-flange-pole rotor structure will induce non-linear magnetic filed in the air gap between armature and rotor, so the reluctance torque is not easy to handle. The switched reluctance motor is considered hard to control at the early stages of development. In recently years, with the rapid improvement of power electronic devices and microprocessor chips, the engineers and researchers pay more attentions to overcome the difficulties encountered in both the software and hardware step by step. It can now exert the motor¡¦s capability to contend with the inductor motor and the alternating current motor. Furthermore, it is more advantageous than others in the high energy density, high temperature and adverse circumstances. It has obviously caught caused the industry¡¦s attention and the academia's research interests. The work of this is to design and develop a drive system for the switched reluctance motor drive system by using the 32-bit floating point Digital Signal Processor, and operate it in coordination with the peripheral circuits. Finally, the study will integrate the graph control programming to design a monitoring and control system with Man-Machinery Interface (MMI) for monitoring voltage, current and speed of the switched reluctance motor drive system.

Switched Reluctance Machine (SRMs) are receiving significant attention for industries and homes in the last decade. Due to their rugged brushless design, high reliable and an outstanding performance over a wide speed range. The stator and rotor of an SRM have a double salient pole and the rotor has no windings and magnets, its torque generating is quite nonlinear and has high torque ripple. Therefore, sophisticated switching and control technologies are needed to improve its driving performance. The cost and performance of SRM drives are highly dependent on the converter topologies and motor structure, so that developments in the convert topologies have been made in parallel with motor design. The objective of this thesis is proposed three phase Switched Reluctance Machine using a fly back resistor C Dump Converter to replace the tradition Bridge Converter. It can reduce switching losses, to reduce converter production cost with a simpler circuit. At the end, a digital signal processor based control system is used to test the laboratory make drives .

­^¤å´£­n¡G The objective of this thesis is to simultaneously achieve two- dimensional control of transverse flux linear switched-reluctance machine (LSRM). Based on a theoretical matrix decomposition scheme, the overall structure of the control and drive systems can be constructed, and the associated man/machine interface can be designed. A fuzzy inference scheme has been selected to control the machine motion, while an orthogonal scheme has been developed to control the machine lift force. By realizing the control algorithm through digital signal processor (DSP), results show that the LSRM will be quite applicable for the desired operations of magnetic levitated vehicle.

The objective of this thesis is to present the algorithm of achieving speed and lift force controls of transverse flux linear switched-reluctance machine (LSRM) simultaneously. A high-speed digital signal processor based (DSP-based) switching controller will be implemented, and the desired speed control objective is realized by using a fuzzy control scheme. On the other hand, by using an indirect field-oriented control scheme, the LSRM reluctance forces, which are magnetically decoupled and position dependent, can be projected onto sets of stationary axes that are aligned with the motor fixed secondary poles. Hence by controlling flux on the specific stationary axis, the machine lift force can be properly controlled. Finally, adequate duty cycle distribution will be discussed and examined to asynchronously supply the required speed and lift force control objectives simultaneously.

This dissertation contains the results of research conducted on the design and control characterization of a Switched Reluctance Generator (SRG) for maximum output power. The SRG is an attractive solution to the increasing worldwide demand of electrical energy. It is low cost with a rugged structure, operates with high efficiency over a wide speed range, and is fault tolerant. In many applications, size and weight are the main criteria in selecting the generator. Hence, in design and control of the generator, system designers always strive for increasing power density, or in other words, maximizing the output power for a given size. Despite the extensive research on the motoring operation of the Switched Reluctance Machine, only a few publications have investigated the generating mode of operation of this machine. Results and algorithms from this research can be referenced for better utilizing the SRG in many applications. As the first stage to output power maximization, design parameters and control variables affecting the average output power of the SRG are identified through a systematic approach. The optimal values for maximizing the output power are found through an analytical approach and iterative simulations. The results are then verified experimentally. After finding the optimal values for control variables, a controller is designed. This controller is model dependent. If the model used for design is not accurate or the machine parameters are deviated from the designed values, the machine will not generate the maximum output power. Therefore, a self-tuning algorithm, based on a local search method, is proposed and experimentally tested. It works effectively and does not need extra hardware or rigorous calculations. The attempts to benefit from the SRG may look tantalizing, but it poses a challenge as well. Output power maximization can lead to an oversized SRG converter and its output filter, which will reduce the overall power density of the motor drive. The last piece of this dissertation analyzes the effect of a commutation algorithm on the output filter, reducing its size with active control of phase currents, and proposing a novel control algorithm that was investigated through experiments over all of the speed range.

The objective of this dissertation is to study the switched reluctance machine (SRM) electromagnetic design and optimization. The research of electric machines is mostly driven by the motivation for higher efficiency and lower cost. The demands for high-performance electric machines also come from the development of emerging industries, such as electric vehicles (EV), hybrid electric vehicles (HEV), renewable energy conversion, energy storage and precision manufacturing. The additional requirements for those applications include volume, weight, speed, torque, reliability, fault tolerance capability, etc. The focus of the research effort is on the high speed and high torque applications, where the SRM stands out compared to other types of machines. The conventional design method significantly depends on the designer’s experience, which uses equivalent magnetic circuit models, and therefore the SRM design is not well developed. A novel SRM electromagnetic design and optimization method is developed, which uses the current-fed FEA simulation as the SRM performance estimation tool. This method serves as the main innovation of this research work. First, the proposed method is applicable to any SRM topologies and dimension, and no detailed modeling of a specific SRM configuration is required in advance. Therefore, an automated SRM design and optimization approach is developed. Secondly, great accuracy of the SRM electromagnetic analysis, e.g. flux density, torque, and current calculation, is achieved by using FEA simulation instead of simplified magnetic circuit approximations. This contribution is particularly significant when considering the poor accuracy of conventional SRM analytical analysis methods, where several assumptions and approximations are used. Lastly, the proposed design method takes the typical SRM control strategy into account, where the excitation current profile is characterized as a trapezoid. This method adapts the flux linkage of the first FEA simulation result to specify the excitation current profile for the second FEA simulation, so the calculated SRM performance in FEA simulation agrees with the measurement on a practical machine. The proposed SRM design and optimization method is used for a 12/8 SRM rotor design and for a complete 4/2 SRM design. These design examples validate the applicability of the proposed method to different SRM configurations and dimensions. Detailed design steps are presented for both design cases, and the selection of the parametric design variables are also discussed. The optimization results are demonstrated using multi-dimension diagrams, where the optimal design with the highest torque can be easily identified. The FEA simulation results are compared to the experimental results of a fabricated SRM prototype, and good agreement is found. In addition, a new rotor configuration with a flux bridge is proposed for an ultra high speed SRM design. The primary motivation of this rotor topology is to reduce the windgae losses and the acoustic noise at a high speed of 50,000 rpm. However, care must be taken for the flux bridge design, and the impact of different flux bridge thicknesses to the SRM performance is studied. Meanwhile, the manufacturing difficulties and the mechanical stresses should also be considered when fabricating the flux-bridge rotor. As a result, two SRM prototypes are built, and the two rotors are one without a flux bridge and one with a flux bridge. The prototypes are tested at different speeds (10,000 rpm, 20,000 rpm and 50,000 rpm) respectively, and the experimental results show good agreement with the FEA simulation results.

Η παρούσα διπλωματική εργασία πραγματεύεται την μελέτη και κατασκευή ενός κυκλώματος για την οδήγηση ενός κινητήρα μαγνητικής αντίδρασης. Σκοπός είναι η μελέτη και κατασκευή ενός κυκλώματος τριφασικού αντιστροφέα τάσης για τηνλειτουργία και τον έλεγχο των στροφών ενός κινητήρα μαγνητικής αντίδρασης. Αν θέλαμε νακάνουμε μια περιγραφή του κινητήρα μαγνητικής αντίδρασης και να δώσουμε έναν ορισμό,θα μπορούσαμε να πούμε ότι: «Ο κινητήρας μαγνητικής αντίδρασης βασίζει τη λειτουργίατου στη ροπή αντίδρασης (reluctance torque), ροπή αντίδρασης ονομάζεται η ροπή που επάγεται σε ένα σιδερένιο αντικείμενο όταν κάποιο εξωτερικό μαγνητικό πεδίο αναγκάζει το αντικείμενο αυτό να ευθυγραμμιστεί με το πεδίο. Αυτή η ροπή αναπτύσσεται επειδή το εξωτερικό μαγνητικό πεδίο επάγει ένα πεδίο στο σίδηρο του αντικειμένου, το οποίο τείνει ναευθυγραμμιστεί με το μαγνητικό πεδίο που το προκάλεσε.» Αρχικά μελετώνται οι βασικές αρχές λειτουργίας του κινητήρα μαγνητικής αντίδρασης. Αναλύεται τομαθηματικό μοντέλο που διέπει τη λειτουργία του και γίνεται αναφορά στη μορφή και τα βασικά κατασκευαστικά χαρακτηριστικά του. Επίσης γίνεται μια σύντομη αναδρομή στην ιστορία των κινητήρων μαγνητικής αντίδρασης καθώς και μία σύγκριση αυτού του είδους κινητήρα με άλλουςκινητήρες εναλλασσομένου ρεύματος. Και αναλύονται τα πλεονεκτήματά του που τον καθιστούνανταγωνιστικό προς αυτούς. Στη συνέχεια γίνεται μια θεωρητική ανάλυση του κυκλώματος του τριφασικού αντιστροφέα τάσηςπου κατασκευάσαμε, καθώς και όλων των υπολοίπων κυκλωμάτων που είναι αναγκαία για τηλειτουργία του. Επιπροσθέτως αναλύεται η μέθοδος παλμοδότησης των διακοπτικών στοιχείων τουαντιστροφέα τάσης που χρησιμοποιήσαμε , και είναι η «Ημιτονοειδής Διαμόρφωση Εύρους Παλμών» Στο επόμενο βήμα αναλύουμε τον τρόπο κατασκευής του κυκλώματος του τριφασικού αντιστροφέατάσης που ακολουθήσαμε καθώς και του πλήρους κυκλώματος παλμοδότησης του. Ενώ γίνεται καιαναλυτική περιγραφή του βιομηχανικού μικροελεγκτή πουχρησιμοποιήσαμε για την παραγωγή τωνπαλμών , με τη μέθοδο της «Ημιτονοειδούς Διαμόρφωσης Εύρους Παλμών» Τέλος παραθέτουμε παλμογραφήματα και μετρήσεις που προέκυψαν από τα πειράματα πουδιενεργήθηκαν αφότου κατασκευάσαμε το κύκλωμα οδήγησης του κινητήρα μαγνητικής αντίδρασης. / The purpose of this thesis is the analysis and construction of a three phase reluctance motor drive system. At first the special characteristics of the syncronous reluctance motors are analyzed. After that there is a theoretical analysis of the three phase inverter circuit, and finally is described the construction of the drive system

This work is intended to contribute with knowledge to the area of electic motorsfor propulsion in the vehicle industry. This is done by first studying the differentelectric motors available, the motors suitable for vehicle propulsion are then dividedinto four different types to be studied separately. These four types are thedirect current, induction, permanent magnet and switched reluctance motors. Thedesign and construction are then studied to understand how the different typesdiffer from each other and which differences that are of importance when it comesto vehicle propulsion. Since the amount of available data about different electricmotors turned out to be small a tool was developed to use for collecting data fromthe sources available which can be for instance product sheets or articles with informationabout electric motors. This tool was then used to collect data that wasused to create models for the different motor types. The created motor models foreach motor type could then be used for simulating vehicles to investigate how thespecific motor is suited for different vehicles and applications. The work also containsa summary of different electric motor comparison studies which makes it agood source of information during motor type selection in the process of designingan electric vehicle.

The switched reluctance motor (SRM) is receiving attention because of its merits: high operating temperature capability, fault tolerance, inherent shoot-through preventing inverter topology, high power density, high speed operation, and small rotor inertia. Rotor position information plays a critical role in the control of the SRM. Conventionally, separate position sensors, are used to obtain this information. Position sensors add complexity and cost to the control system and reduce its reliability and flexibility. In order to overcome the drawbacks of position sensors, this dissertation proposed and investigated a position sensorless control system that meets the needs of an electric actuator application. It is capable of working from zero to high speeds. In the control system, two different control strategies are proposed, one for low speeds and one for high speeds. Each strategy utilizes a state observer to estimate rotor position and speed and is capable of 4 quadrant operation. In the low speed strategy a Luenberger observer, which has been named the inductance profile demodulator based observer, is used where a pulse voltage is applied to the SRMs idle phases generating triangle shaped phase currents. The amplitude of the phase current is modulated by the SRMs inductance. The current is demodulated and combined with the output of a state observer to produce an error input to the observer so that the observer will track the actual SRM rotor position. The strategy can determine the SRMs rotor position at standstill and low speeds with torques up to rated torque. Another observer, named the simplified flux model based observer, is used for medium and high speeds. In this case, the flux is computed using the measured current and a simplified flux model. The difference between the computed flux and the measured flux generates an error that is input to the observer so that it will track the actual SRM rotor position. Since the speed ranges of the two control stragegies overlap, the final control system is capable of working from zero to high speed by switching between the two observers according to the estimated speed. The stability and performance of the observers are verified with simulation and experiments.

Thermal modeling is an important aspect of electric motor design. Numerous techniques exist to predict the temperatures in a motor, and they can be incorporated in the design of a thermal model for a new type of electric motor. This work discusses the available modeling techniques and determines which methods are applicable for medium-sized motors with either natural convection or forced convective cooling over irregular geometry. A time-dependant thermal model, with thermal transport parameters based upon geometric and simplified air flow information, is developed based on a discrete lumped parameter model with several modifications to improve accuracy. The model was completed with the aid of nine experiments, and the result is a thermal model that exhibits an absolute error of less than 6.1??C for the nine test runs at three different currents between 8.4 A rms and 28.2 A rms and three cooling levels, natural, 10.7 CFM and 24.4 CFM.