Induction Motor

Micha³ MAJCHROWICZ * MODEL ANALITYCZNY SILNIKA PRZE£¥CZALNEGO RELUKTANCYJNEGO (SRM) NA POTRZEBY OPTYMALIZACJI JEGO KONSTRUKCJI STRESZCZENIE W artykule przedstawiono sposób modelowania indukcyjnoci uzwojenia fazowego silnika reluktancyjnego prze³¹czalnego (SRM) oparty na metodzie sieci reluktancyjnych (MSR). Model pozwala wyznaczyae przebieg indukcyjnoci w³asnej uzwojenia fazowego w zale¿noci od k¹ta po³o¿enia wirnika, dla ró¿nych wartoci parametrów geometrycznych silnika (m.in. szerokoci biegunów stojana i wirnika). Model uwzglêdnia nieliniowoae magnetyczn¹ rdzenia. Artyku³ zawiera opis konstrukcji bazowej analizowanego silnika, opis procedury wyznaczania indukcyjnoci uzwojenia oraz przyk³adowe wyniki otrzymane przy u¿yciu modelu. Dla ró¿nych wartoci wybranych parametrów geometrycznych pokazano przebiegi k¹towe indukcyjnoci oraz jej pochodnej wzglêdem k¹ta po³o¿enia wirnika i porównano je z wynikami obliczeñ polowych oraz wynikami otrzymanymi przy u¿yciu podobnego modelu innego autora. Ponadto pokazano wyniki wstêpnej analizy wra¿liwoci parametrów przebiegu k¹towego indukcyjnoci (zdefiniowanych tak, aby charakteryzowa³y moment) na zmiany geometrii silnika. Model zostanie wykorzystany do optymalizacji konstrukcji silnika. Model zosta³ zaimplementowany w rodowisku MATLAB. S³owa kluczowe: silnik reluktancyjny prze³¹czalny, SRM, metoda sieci reluktancyjnych A method of determining inductances of a switched reluctance motor (SRM) based on reluctance network analysis has been presented in the paper. The model allows calculating a self inductance function of one phase versus rotor angular position, for a few variable parameters of the geometry (e.g. a width of the rotor and stator poles). The model takes into consideration the magnetic non-linearity of a core. The paper comprises a description of a base construction of the analyzed motor, a procedure of calculating the inductance and results obtained by means of the model. Inductance functions and their derivatives versus rotor angular position for selected variable parameters of the geometry have been presented for the proposed model, an earlier model of another author, and finite element calculations. Moreover, a sensitive analysis has been performed for the inductance function as well as three criterial functions assumed to be used in optimization. The model is designed to optimize of the SRM construction. The model was implemented in the MATLAB environment.

In this article, a new soft starting control scheme based on an artificial neural network (ANN) is presented for a three-phase induction motor (IM) drive system. The main task of the control scheme is to keep the accelerating torque constant at a level based on the value of reference acceleration. This is accomplished by the proper choice of the firing angles of thyristors in the soft starter. Using the ANN approach, the complexity of the online determination of the thyristors firing angles is resolved. The IM torque-speed characteristic curves are firstly used to train the ANN model. Secondly, the IM-soft starter system is modeled using MATLAB/SIMULINK. To prove the effectiveness of the proposed ANN-based acceleration control scheme, different reference accelerations and loading conditions are applied and investigated. Finally, a laboratory prototype of 3 kW soft starter is implemented. The proposed control scheme is executed in a real-time environment using a digital signal processor (Model: TMS320F28335). The simulation and real-time results significantly confirm that the proposed controller can efficiently reduce the IM starting current and torque pulsations. This in turn ensures a smooth acceleration of the IM during the starting process. Moreover, the proposed control scheme has the superiority over several soft starting control schemes since it has a simple control circuit configuration, less required sensors, and low computational burden of the control algorithm.

Induction motors are widely used in industry due to their promising performance. Majority of induction motors are used in inverter based drives in industrial setups. Efforts are being put in the fault analysis of induction motors. Most of the analysis available in literature discusses the failure of electronic components like power MOSFET, optocoupler failure, failure of pulse generation card etc. This research work is a continuation of fault analysis studies of an inverter fed induction motor drives under different fault conditions. This paper presents the effect of dc link capacitor open circuit on the performance of inverter fed induction motor. Effect on stator current, inverter output, the speed and torque of the motor are particularly studied in this paper. The faults in the DC link is generally not that common but there is always a chance of capacitor failure. The simulated results presented in this paper can augment the efforts for the reliability enhancement of induction motor drives.

Induction motors are widely used in industrial power plants due to their robustness, reliability and high performance under variable operating conditions in the electrical power system. Modern industrial progress is dependent on these ruggedly constructed induction motors. Almost every sophisticated process of the industry is based on induction motors. Most of these motors are controlled by means of inverters that change the line frequency. The change in parameters of inverter makes it possible to control the motor according to the design requirements. The reliability of inverter based motor control is an important issue for industrial applications and therefore, it becomes very vital for design engineers to have comprehensive analysis of the inverter fed induction machine. This paper investigates one of the faults that may occur on the DC link of an inverter fed induction motor. The effect of the capacitor short circuit is presented in this paper. It also deals with the effects of short circuited capacitor on freewheeling diode. DC link capacitors are well designed and even the probability of capacitor failure is high, it is always a rare case if they puncture, however this analysis will add to the reliability of the induction machine under variable operating condition.

This paper presents a design methodology for electric machines (EM). It is based on discrete multi-material topology optimization (TO) and printed material characteristics. Our methodology uses the Bi-directional Evolutionary Structural Optimization (BESO) heuristic for optimization, and to maximize EM torque, we propose a reformulated problem to accelerate simulation time. It permits considering both ferromagnetic materials and permanent magnets with discrete variables. Printed material characteristics are taken into account, considering several process parameters. A comparison of the final designs for different BH curves is presented.

Bu caly?mada, dogrudan moment kontrol (DTC) yontemi kullanan bir asenkron motor surucu sistemi analiz edilmi?tir. Bunun icin, asenkron motorun matematiksel d-q modelinden yararlanylarak, DTC kontrollu asenkron motor surucu sisteminin Matlab/Simulink ile benzetimi yapylmy?tyr. DTC yontemi ile kontrol edilen asenkron motorun hem gecici hem de surekli durumda hyzynyn, uretti?i momentin ve stator ile rotor akymlarynyn zamana gore de?i?imleri incelenmi?tir. Surucu sistemin incelenmesinde, motorun belli zaman aralyklarynda bo?ta veya yuk altynda bulundu?u dikkate alynarak hyz, moment ve akym sonuclary elde edilmi?tir. Surucu sistem modelinde bulunan aky ve moment kontrolorlerinin histerezis band geni?likleri evirici anahtarlama frekansyny etkiledi?i ve moment dalgalanmalaryna sebep oldu?u gorulmu?tur. Bu caly?mada, aky ve moment kontrolorlerinin histerezis band geni?likleri aky ve moment dalgalanmalaryna neden oldu?u icin, once uygun band geni?liklerinin secilmesi gerekti?i ve daha sonra ...

In Mexico, the linking of universities and research and development centers with the industry is an issue which has been present for more than a decade in economic and social development plans and schemes advanced by federal and state governments. The goal of this connection is to include and apply scientific and technical knowledge into industrial production, to foster industrial competitiveness.

In this paper, we are interested, in a first time, at the study and the implementation of a V/f control for induction machine in real time. After, We are attached to a comparison of the results by simulation and experiment for, speed responses, flux and currents of the real machine, with a DSPACE card and model established by classical identification (Direct Current test , blocked-rotor test, no-load test , synchronous test), to ensure the validity of the established model. The scalar controlled induction motor allows operation of the motor with the maximum torque by simultaneous action on the frequency and amplitude of the stator voltage, with conservation of the ratio V/f. Speed reference imposes a frequency at the inverter supplying the voltages needed to power the motor, which determines the speed of rotation. The maximum torque of the machine is proportional to the square of the supply voltage and inversely proportional to the frequency voltage. So, Keep V/f constant implies a operating with maximum constant torque. The results obtained for the rotor flux and the stator currents are especially satisfactory steady.

In this paper, we are interested, in a first time, at the study and the implementation of a V/f control for induction machine in real time. After, We are attached to a comparison of the results by simulation and experiment for, speed responses, flux and currents of the real machine, with a DSPACE card and model established by classical identification (Direct Current test , blocked-rotor test, no-load test , synchronous test), to ensure the validity of the established model. The scalar controlled induction motor allows operation of the motor with the maximum torque by simultaneous action on the frequency and amplitude of the stator voltage, with conservation of the ratio V/f. Speed reference imposes a frequency at the inverter supplying the voltages needed to power the motor, which determines the speed of rotation. The maximum torque of the machine is proportional to the square of the supply voltage and inversely proportional to the frequency voltage. So, Keep V/f constant implies a operating with maximum constant torque. The results obtained for the rotor flux and the stator currents are especially satisfactory steady.

Switched reluctance motors (SRMs) are an attractive choice for electric vehicle (EV) applications but suffer from certain limitations, such as high torque ripple and acoustic noise. This paper presents ongoing research and development activity details to enhance the performance of SRMs for EV applications. The poor performance of a conventional SRM which is available in market with a rating of 8/6 poles, 48 V, 500 W, and 2,000 rpm is tested. A motor model of the same rating is developed using ANSYS Maxwell software. Motor performance parameters important for EV applications, such as efficiency, rated torque and torque ripple are compared with the conventional motor. One novel technique to reduce the torque ripple of SRM is discussed along with the results. Torque ripple of developed software model is reduced by 24.52% without a reduction in the efficiency and rated torque of the motor. The performance of the developed SRM software model is better compared to conventional SRMs available in the market. 2D and 3D models of SRM were presented using ANSYS Maxwell software.

The tailpipe emissions caused by vehicles using internal combustion engines are a significant source of air pollution. To reduce the health hazards caused by air pollution, advanced countries are now adopting the use of electric vehicles (EVs). Due to the advancement of electric vehicles, research and development efforts are being made to improve the performance of EV motors. With a nominal reference stator flux, the classical induction motor drive generates significant flux, torque ripple, and current harmonics. In this work, a teamwork optimization algorithm (TOA)-based optimal stator flux strategy is suggested for torque ripple reduction applied in a classical direct torque-controlled induction motor drive. The suggested algorithm's responsiveness is investigated under various steady-state and dynamic operating conditions. The proposed DTC-IM drive's simulation results are compared to those of the classical and fuzzy DTC-IM drives. The proposed system has been evaluated and found to reduce torque ripple, flux ripple, current harmonics, and total energy consumption by the motor. Further, a comparative simulation study of the above methods at different standard drive cycles is presented. Experimental verification of the proposed algorithm using OPAL-RT is presented. The results represent the superiority of the proposed algorithm compared to the classical DTC and fuzzy DTC IM drives. The torque ripple reduction approach described in this study can also be applied to all induction motors, not only those for electric vehicles or hybrid electric vehicles (HEVs).

Induction motors are used in all industries and are the major element of energy consumption. Faults in motor degrade the motor efficiency and result in more energy consumption. Bearing faults are reported to be the major reason for the motor breakdown and a lot of papers have been reported to focus on bearing fault diagnostics. However, low classification accuracy is the main hurdle in adopting the available fault classification algorithms. This paper has presented a novel classification algorithm using the Catboost classifier and timedomain features. The developed algorithm was tested on the laboratory test setup. The fault classification accuracy of 100 % was achieved through the proposed method.

Induction motors are mainly used for variable load applications and it is vital to have a condition monitoring system with capabilities to diagnose motor faults in variable load conditions. The environment noise varies has non-linear relation with motor load and it challenges the decision making capability of the condition monitoring system. This paper addresses the issue of reliable decision making on the existence of bearing faults in variable load conditions. Two type of threshold schemes have been proposed to reliably diagnose bearing faults in Park vector modulus spectrum. The performance of the developed threshold based condition monitoring system has been analyzed theoretically and experimentally.

Induction motors are work-horse of the industry and major element in energy conversion. The replacement of the existing non-adjustable speed drives with the modern variable frequency drives would save considerable amount of electricity. A proper control scheme for variable frequency drives can enhance the efficiency and performance of the drive. This paper attempt to provide a rigorous review of various control schemes for the induction motor control and provides critical analysis and guidelines for the future research work. A detailed study of sensor based control schemes and sensor-less control schemes has been investigated. The operation, advantages, and limitations of the various control schemes are highlighted and different types of optimization techniques have been suggested to overcome the limitations of control techniques.

Recently, speed sensorless control of induction motor drives received great attention to avoid the different problems associated with direct speed sensors. However, low speed operation with robustness against parameter variations remains an area of research for sensorless systems. Stator resistance is of greatest importance for good operation of speed sensorless systems in low speed region. In this paper, a sliding mode current observer for an induction motor is presented. An estimation algorithm based on this observer in conjunction with Popov's hyper-stability theory is proposed to calculate the speed and stator resistance independently. The proposed speed observer with parallel stator resistance identification is firstly verified by simulation. Experimental results are included as well to demonstrate the good performance of the proposed observer and estimation algorithms at very low speed.

Direct torque control (DTC) of three phase induction motors allows a high dynamic performance to be obtained with a very simple control scheme. It is based on the stator flux orientation in which the stator flux is used as a main control variable. Therefore in DTC, determination of stator flux is always of first and primary concern. This paper investigates the stator flux estimation problem over the entire speed range. A hybrid stator flux estimator which combines the voltage model and current model with a PI controller is proposed. The proposed method does not depend on the angular speed and reduces the problems associated with pure integrators of voltage model at low speed. An improved stator resistance adaptation scheme is used to enhance the system performance. Thus, the drive system is capable of working from very low speed up to high speed and exhibits good dynamic and steady-state performances. The effectiveness of the proposed scheme is investigated, and good results have been achieved for both steady-state and dynamic operating conditions.

The controllability of torque in an induction motor without any peak overshoot and less ripples with good transient and steady state responses form the main criteria in the designing of a controller. Though, PI controller is able to achieve these but with certain drawbacks. The gains can not be increased beyond certain limit so as to have an improved response. Moreover, it introduces non linearity into the system making it more complex for analysis. Also it deteriorates the controller performance. With the advent of artificial intelligent techniques, these drawbacks can be mitigated. One such technique is the use of Fuzzy Logic in the design of controller either independently or in hybrid with PI controller. This paper proposes a unique set of fuzzy logics for the speed controller design to be used in vector controlled three phase induction motor. The results obtained from the model using proposed Fuzzy Logic Controller and PI Controller are compared. It can be concluded that use of Fuzzy logic improves and smoothens out the ripples in the motor torque and stator currents. It also facilitates in limiting the magnitude of the torque and current values within the specified range in any kind of disturbance, either provided by the speed removal or by sudden application and removal of load torque. This has been verified through the simulation results of the model built completely in a MATLAB/SIMULINK environment.

A circuit for speed controlling of three phase motor induction was designed and implemented. The circuit is using triac as main of component and supported by diac, diode, and the other passive electronics component. The result is a prototype of the speed controlling circuit. The circuit was implemented in plastic industry for keeping of the plastic yarn, so we can optimize production process and increasing the result as better quality and efficient. Keywords: control, speed , triac, motor induction

In this paper, Induction Motors (IM) are widely used in the industrial application due to a high power/weight ratio, high reliability and low cost. A Space Vector PWM (SVPWM) is utilized for PWM controlling scheme. The performance of both the speed and torque is promoted by a modified PI controller and V/F scalar control. A scalar control is a simple method and it's operated to control the magnitude of the control quantities in constant speed application. V/F scalar control has been implemented and compared with the PI controller. The simulation results showed that Indirect Field oriented control (IFOC) induction motor drive employ decoupling of the stator current components which produces torque and flux. The complete mathematical model of the system is described and simulated in MATLAB/SIMULINK. The simulation results provides a smooth speed response and high performance under various dynamic operations.

A comparative analysis of three phase eleven level Diode Clamped Multilevel Inverter (DCMLI) and hybrid inverter is performed in this paper in which the later requires fewer carrier signals, less number of devices and gate drive circuits. The performance is evaluated using Phase Disposition (PD), Alternate Phase Opposition Disposition (APOD) and Carrier Overlapping (CO) Sinusoidal Pulse Width Modulation (SPWM) methods. The hybrid multilevel inverter has superior features over diode clamped multilevel inverters and is more efficient since the positive levels of the inverter that are generated by high frequency switches (level generation part), are reversed by low frequency switches (polarity generation part) when the voltage polarity is required to be changed for negative polarity. Therefore, the overall cost and complexity of the hybrid inverter are greatly reduced particularly for higher inverter output voltage levels. Simulation is performed for three phase eleven level diode clamped multilevel inverter and hybrid multilevel inverter using MATLAB/Simulink for induction motor load and the total harmonic distortion is evaluated at different load torques.

A Ground Fault Circuit Interrupter (GFCI) is a safety device that prevents electric shock by using fundamental electromagnetic principles. Its operation centers on a sensor, a toroidal iron core, that monitors the current in the "hot" and "neutral" wires. In a normal circuit, these two currents are perfectly equal and opposite, creating magnetic fields that cancel each other out, resulting in zero net magnetic flux in the core. When a dangerous ground fault occurs, some current "leaks," creating an imbalance. This imbalance produces a net changing magnetic flux, which, according to Faraday's Law of Induction, induces a small voltage in a sensing coil. A quantitative model shows that a hazardous 5 mA fault current generates a detectable peak voltage of about 1.33 millivolts, which is then amplified to trip a relay and cut off the power in a fraction of a second.

This paper presents a novel algorithm (patented) for detecting the early CT saturation in bus differential protection, which, combing with the late CT saturation block zone and other security enhancement features provides great securities to the bus differential relay on external faults, and also maintains the relay with high sensitivity and fast operation for internal faults. Index Terms – CT saturation, Bus protection, 87B Differential Protection

This study, titled Comparative Evaluation of Machine Learning Models for Fault Detection in Induction Motors presents a comparative evaluation of machine learning (ML) models for fault detection in three-phase induction motors, which are essential components in industrial applications. Despite their robust construction, these motors are prone to faults such as stator winding failures, rotor defects, and overvoltage conditions that can cause unexpected breakdowns and operational losses. Traditional fault detection techniques often lack the sensitivity and consistency required for early fault detection. To address this gap, this research investigates the effectiveness of four supervised ML algorithms-Random Forest (RF), K-Nearest Neighbors (KNN), Gradient Boosting Machine (GBM), and Support Vector Machine (SVM). A 7.5 kW induction motor was modeled using MATLAB/Simulink, simulating six operating conditions to generate relevant datasets. These were preprocessed and evaluated in Pytorch using standard classification metrics: accuracy, precision, recall, and F1-score. Among the models, Random Forest delivered the best performance with an average accuracy of 94.7%, precision of 93.7%, recall of 92.7%, and F1-score of 93.2%. GBM followed closely with an accuracy of 92.0% and F1-score of 90.5%, while SVM achieved moderate results. KNN showed the lowest performance across all metrics. The results confirm Random Forest as the most robust and reliable model for industrial motor fault detection.

This paper proposes an improved modulation technique to control a modified H-Bridge solar photovoltaic (PV) fed seven-level inverter to drive a single-phase 230V, 1/2 HP capacitor start-run induction motor (IM). An improved H-bridge 7-level inverter topology is achieved by reducing the number of switches required to produce seven distinct voltage levels. The speed of the IM is controlled using the concept of scalar control. The pulse width modulation (PWM) signals applied to the switches of the 7-level inverter are generated using a combination of three identical sine wave signals. This combination acts as reference signals, which have an offset equal to the amplitude of the triangular carrier signal. The proposed method is implemented in MATLAB / Simulink ® environment, and its result demonstrates that the seven-level inverter can successfully suppress harmonics by more than 50% as compared to the three and five-level inverter without the use of an external LC filter. Moreover, the voltage stress across switches is reduced by 35% even though a smaller number of switches are used in the proposed method.

This paper presents a method of fault identification of induction motor drive by means of the application of wavelet analysis of a tested signal and a model of neural network with supervised learning, and also a model of neural network processed in the next epochs by means of algorithm making essential changes of parameters of this network. The tests which were executed on three important state variables, describing physical quantities of the chosen induction motor drive model indicated the usefulness of the method used for diagnostic purposes, allowing the identification of the fault type occurring in the induction motor drive in the initial phase of formation. Streszczenie. W artykule przedstawiono metode identyfikacji uszkodzen napedu z silnikiem indukcyjnym przy zastosowaniu analizy falkowej badanych sygnalow i modelu sieci neuronowej. Ukazany zostal model sieci neuronowej przetwarzanej w kolejnych stadiach za pomocą algorytmu dokonującego istotnych zmian parametrow tej sieci. B...

The whirling speed in rotor dynamics, with reference to solid mechanics, is the velocity that excites the natural frequency of rotating object or assembly. Proper estimation of this whirling speed is one of the key factors that are to be considered at design stage of electrical machines as induction motors. This research paper deals with estimation of whirling speed of an induction motor. The work involves theoretical estimation of whirling speed and its validation using ANSYS.

Permanent magnet synchronous motor (PMSM) is widely used in different applications because of their different key operation features. But despite having important key features, PMSM suffers from torque ripple when simple control techniques like direct torque control (DTC) are employed. Several approaches have been raised by many researchers to lessen the ripple when DTC is used for controlling the PMSM drive. In this work, duty ratio-optimized DTC control, which has the same simplicity as conventional DTC (CDTC), and delay compensation for input signal prediction are proposed. In the proposed system, to determine the duty ratio, slope manipulation was made by considering the minimization of torque error and forcing the developed torque to be equal to the reference torque at the end of the span. An online slope determination approach was employed to compute the duty ratio. MATLAB 2021b is used for simulation purposes. The dynamics and steady-state performance of the proposed scheme were tested for both variable-load and variable-speed operations. In addition, the harmonic performance and ratio of harmonic power loss to total active power loss of the motor were evaluated. In general, the proposed scheme performs effectively in reducing steady-state ripple and harmonic.

MOSFET is an active device that was developed from a semiconductor material with the advantages of switching systems and strengthening better than bipolar transistors, so that is widely used in computers and telecommunications. This study aims to create simple as a basic circuit MOSFET motor controller. The method used is the R & D to create a circuit design, prepare materials and equipment, assembling, and testing. The test results obtained that type MOSFET BUZ11, is able to control a DC motor starting on voltage V GS = 0.5 V. Farther up the value of V GS voltage, the faster the motor rotation control. Based on the test results, then the media circuit MOSFET can be used as the basis of learning basic electronic media on the concept of MOSFET.

This paper proposes a robust nonlinear current controller that deals with the problem of the stator current control of a six-phase induction motor drive. The current control is performed by using a state-space representation of the system, explicitly considering the unmeasurable states, uncertainties and external disturbances. To estimate these latter effectively, a time delay estimation technique is used. The proposed control architecture consists of inner and outer loops. The inner current control loop is based on a robust discrete-time sliding mode controller combined with a time delay estimation method. As said before, the objective of the time delay estimation is to reconstruct the unmeasurable states and uncertainties, while the sliding mode aims is to suppress the estimation error, to ensure robustness and finite-time convergence of the stator currents to their desired references. The outer loop is based on a proportional-integral controller to control the speed. The stabilit...

This paper presents the design and simulation of two types of DC-DC converters, namely, Buck and Ćuk converters using Simulink in a MATLAB environment. The step-down modes of the two converters were compared and the result discussed. Both converters use 17V DC as the input voltage and 12V DC as the desired output voltage. The converters are mainly used in photovoltaic solar charge controllers to either step up or step down the fluctuating DC voltage from the solar panels for effective battery charging. The Buck converter type is popularly used in the solar charge controllers for the aforementioned purposes, but the need for further enhancing the charging process in order to extend the battery life requires the design of the Ćuk type converter. The Ćuk converter has several advantages over its Buck counterpart. The design and simulation of the two converters were carried out in order to determine, from their output responses, which of them has lower ripples, faster response, settling time, and moves closer to the desired output voltage value.

This paper presents the design and simulation of two types of DC-DC converters, namely, Buck and Ćuk converters using Simulink in a MATLAB environment. The step-down modes of the two converters were compared and the result discussed. Both converters use 17V DC as the input voltage and 12V DC as the desired output voltage. The converters are mainly used in photovoltaic solar charge controllers to either step up or step down the fluctuating DC voltage from the solar panels for effective battery charging. The Buck converter type is popularly used in the solar charge controllers for the aforementioned purposes, but the need for further enhancing the charging process in order to extend the battery life requires the design of the Ćuk type converter. The Ćuk converter has several advantages over its Buck counterpart. The design and simulation of the two converters were carried out in order to determine, from their output responses, which of them has lower ripples, faster response, settling time, and moves closer to the desired output voltage value.

This study described the design of a 3-phase AC Induction Motor (ACIM) vector control drive with position encoder coupled to the motor shaft. Approach: It was based on free scale's (Motorola's) 68k micro processor devices. Although the free scale 56F80x (56800 core) and 56F8300 (56800E core) families were well-suited for digital motor control and offer all things was needed, but we decided to realize a complete vector controller with a powerful 68k processor. Results: Obviously all 680X0 and many 683XX can overcome this task very easily, but we decided 68332 for time consuming because it combines high-performance data manipulation capabilities with powerful peripheral subsystems. All software and hardware was based on Peter J. Pinewski's nice research from Motorola. Conclusion: In this study the overall software algorithm and in two fellow papers the hardware schematics and performance will be described respectively.

This study described the design of a 3-phase AC Induction Motor (ACIM) vector control drive with position encoder coupled to the motor shaft. Approach: It was based on free scale's (Motorola's) 68k micro processor devices. Although the free scale 56F80x (56800 core) and 56F8300 (56800E core) families were well-suited for digital motor control and offer all things was needed, but we decided to realize a complete vector controller with a powerful 68k processor. Results: Obviously all 680X0 and many 683XX can overcome this task very easily, but we decided 68332 for time consuming because it combines high-performance data manipulation capabilities with powerful peripheral subsystems. All software and hardware was based on Peter J. Pinewski's nice research from Motorola. Conclusion: In this study the overall software algorithm and in two fellow papers the hardware schematics and performance will be described respectively.

This study described the design of a 3-phase AC Induction Motor (ACIM) vector control drive with position encoder coupled to the motor shaft. Approach: It was based on free scale's (Motorola's) 68k micro processor devices. Although the free scale 56F80x (56800 core) and 56F8300 (56800E core) families were well-suited for digital motor control and offer all things was needed, but we decided to realize a complete vector controller with a powerful 68k processor. Results: Obviously all 680X0 and many 683XX can overcome this task very easily, but we decided 68332 for time consuming because it combines high-performance data manipulation capabilities with powerful peripheral subsystems. All software and hardware was based on Peter J. Pinewski's nice research from Motorola. Conclusion: In this study the overall software algorithm and in two fellow papers the hardware schematics and performance will be described respectively.

This study described the design of a 3-phase AC Induction Motor (ACIM) vector control drive with position encoder coupled to the motor shaft. Approach: It was based on free scale's (Motorola's) 68k micro processor devices. Although the free scale 56F80x (56800 core) and 56F8300 (56800E core) families were well-suited for digital motor control and offer all things was needed, but we decided to realize a complete vector controller with a powerful 68k processor. Results: Obviously all 680X0 and many 683XX can overcome this task very easily, but we decided 68332 for time consuming because it combines high-performance data manipulation capabilities with powerful peripheral subsystems. All software and hardware was based on Peter J. Pinewski's nice research from Motorola. Conclusion: In this study the overall software algorithm and in two fellow papers the hardware schematics and performance will be described respectively.

The authors present the faults diagnosis by parameter identification of the squirrel-cage rotor induction machine using real data. The model of electric parameter identification of the induction machine from the input-output observations of the stator is elaborated.To experimentally verify this approach, the tests are carried out on four squirrel-cage rotor induction machines especially constructed for the purpose of the diagnosis. All the model parameters of the squirrel-cage rotor induction machine are identifyied by least-squares method. Experimental results show good agreement and confirm the possibility the detection and localization of the faults.

Induction motors are the commonly used motors in power industries, due to its low price, maintenance and easy to control, it consumes about 40% of the electrical energy all over the world. It is very common to find problems of power quality in electric supply systems, among of these problems unbalanced phase voltage and under / over voltage deviation. The developments in the power electronics field have led to an ever-increasing use of static switching devices to control the torque and speed of ac motors. Invariably, the output voltage and current waveforms of these devices are harmonically distorted in shape due to the existence of numerous harmonic orders; they primarily affect the performance operation of induction motors. Symmetrical component approach is adopted to estimate the performance of a three phase induction motor operating with unbalanced supply system or other factors. Further MATLAB/SIMULINK has been used simultaneously for simulation purpose. A new approach is proposed to de-rate the motor operating with these external factors in order to safe induction motors and increase its life time. This paper, therefore, presents a comprehensive study the influence of these external factors on induction motors behavior. A comparative study of induction motor de-rating factors is presented.

This paper deals with literature survey of various existing converter topologies, which have been proposed for adjustable speed single phase induction motor drives (SPIMD). Included in the paper are several newly proposed converter topologies. A study of the merit and demerit of different converter topologies have been carried out. Various converter topologies have been compared in this paper. Among these converter topologies, the adjustable frequency PWM inverter is the best choice for single-phase induction motor drives. However, adjustable-frequency drives have not been widely used with single-phase induction motors. The open-loop constant V/f control law cannot be used with the single-phase induction motor drives as it is used with three phase motors. The variation of the operating frequency at lower speed range with constant load torque causes variation in the motor's slip. A constant V/f control is suitable only over the upper speed range. However, improvements in the low frequency performance require the use of constant power dissipation in the motor. Simulation studies for some of the existing topologies as well as for the proposed ones have been carried out.

In this paper, a sensorless induction motor (IM) drive using speed observer system is presented. The system includes load torque computation for gear fault detection. Nonlinear control method is adopted for controlling the motor over a wide speed range. An LC filter for smoothing current and voltage waveforms is used at the output of the voltage inverter. The use of filter imposes more building of the used observer to avoid using additional current and voltage sensors. An analysis of the motor load torque makes it possible to detect existing problems in the load. The developed algorithm was verified by simulation and experiments for a 1.5 kW induction motor drive system.

Induction motors are commonly used in numerous industrial applications. To maintain a reliable operation of the motor, it is important to identify the potential faults that may cause the motor to fail. Bearing failures are one of the main causes of motor breakdown. The causes of bearing damage have been studied in detail for a long time. In some cases, bearing failed due to the current passing through them. In this thesis, bearing CHAPTER I

In this paper, the effect of pulsewidth modulation (PWM) voltage waveform on the voltage distribution among the stator windings of random wound cage induction motors is studied. First, a method of estimating the high-frequency distributed-circuit parameters of the motor using finite-element analysis is described. From these parameters, an equivalent circuit is formed with the windings represented by partially distributed and partially lumped parameters. Using this equivalent circuit, the voltage distribution among the turns and coils of the motor are simulated using the SABER simulation package. Through simulation, the effect of rise time of the PWM wavefront on the voltage distribution is studied, and it is shown that the rise time of the wavefront has influence on the additional voltage stress on the line-end coil. In order to validate the simulation procedure adapted, the simulation results are compared with experimental results.

Two series-connected two-motor drive systems with a single inverter supply have been proposed recently. The first one consists of two five-phase machines supplied from a single five-phase inverter, whereas the second one comprises one symmetrical six-phase machine, a three-phase machine, and a single six-phase inverter. It has been verified experimentally that, by introducing an appropriate phase transposition in the series connection, completely independent dynamic control of the two machines can be realized using principles of vector control. Detailed dynamic models in the stationary common reference frame have also been reported for the two drive systems. These are taken here as the starting point, and equivalent circuit steady-state representation of the seriesconnected two-motor drive systems is developed. The equivalent circuits can then be used to evaluate steady-state characteristics of the drives in the same manner as it is done for three-phase induction machines, as well as for the inverter design. The dc-link voltage required for operation of the two series-connected machines is investigated next. It is shown that the specific winding connections lead to a dc voltage requirement that is smaller than it would have been had the windings of the two machines been connected directly in series. Experimental results, obtained during steady-state operatio

tor. Through a comparative study using a detailed machine model and the standard dq model, the paper shows that the characteristic frequencies generated by a particular fault are preserved even if the standard dq model is used for estimation of air-gap torque. This is validated through a practical hardware implementation for online spectrum estimation of air-gap torque using TMS320C31, where several faulted cage rotors were used for study. Keywords: Condition monitoring, rotor fault diagnosis, motor current signature analysis, air-gap torque spectrum, air-gap torque estimation.

Effective sensorless dynamic speed estimation is desirable for both speed sensorless motor-drive applications and for on-line induction motor condition monitoring and assessment. In this paper, a sensorless neural adaptive speed filter is developed for induction motors running off a voltage source inverter. The filter is demonstrated by comparisons with experimental speed measurements and spectral speed estimates. In addition to nameplate information required for the initial set-up, the proposed neural speed filter uses only measured motor currents and voltages. Initial training of the speed filter is accomplished off-line, using rotor slot harmonic-based speed estimates. The developed speed filter is tested on data from a healthy motor and motor with 4 broken rotor bars. The resulting speed filtering accuracy compares favorably with speed estimation results reported in the literature. The study demonstrates the feasibility of neural adaptive speed filters for effective inverter-fed induction motor speed estimation, without explicit use of motor model parameters and speed measurements.

This paper deals with the use of a new diagnostic technique based on the multiple reference frames theory for the diagnosis of stator winding faults in a direct-torque-controlled (DTC) induction motor drive. The theoretical aspects underlying the use of this diagnostic technique are presented but a major emphasis is given to the integration of the diagnostic system into the digital-signal-processor (DSP) board containing the control algorithm. Taking advantage of the sensors already built in the drive for control purposes, it is possible to implement this diagnostic system at no additional cost, thus giving a surplus value to the drive itself. Experimental results show the effectiveness of the proposed technique to diagnose stator faults and demonstrate the possibility of its integration in the DSP board.

Growing architectural shelters by manipulating plant growth is not a new design strategy. It is easy to find many examples in traditional architecture or arborsculpture and tree shaping. However there are more sophisticated ways of programming matter to grow 100% organic and disposable architectural devices or usable structures, not only generating cero waste, but also nutrients for the environment. This work explores the possibilities of a material developed by Ecovative Design, which is actually being used for insulating and packaging purposes, to generate usable structures and shelters shifting its scale and slightly modifying its composition.

This paper presents an analysis on the characteristics of the stator winding degradation process. A diagnostic and prognostic parameter, which is derived using the sequence component approach, is proposed. It is estimated using only the measurements of voltages and currents, which are easily obtained, and hence, the method can be implemented in real-time applications. A test is designed for generating stator winding inter-turn fault and accelerating it. The characteristic of the degradation process based on the prognostic parameter is discussed. The collected data is modeled and the remaining useful life (RUL) is estimated.