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One of the legislative regulations aiming at reduced energy consumption in the European Union, is (EC) 640/2009 that imposes requirements of the efficiency of electric motors sold in the Union. This study aimed at examining the effectiveness of these legislative requirements. To illustrate the opportunities of reducing energy consumption by the introduction of more efficient motors, an efficiency measurement of electric motors that drive the fuel feed system in a cogeneration plant in Nybro was intended to be carried out. This was to enable a comparison between the efficiency of existing motors with motors which comply with the efficiency levels in (EC) 640/2009 and to calculate how much the energy consumption would decrease in this energy system if more efficient motors were introduced. The planed measurements could not be carried out to give a reliable result because the plant suffer from the same problem as many other industries in the EU, which is that the motors in this energy system are oversized and operate at low loads. Oversized motors do not operate at their rated efficiency and therefore a comparison of existing motors and motors that comply with the efficiency requirements in (EC) 640/2009 fails to give a correct result, since they would not operate at their rated efficiency if they were installed in this energy system due to the efficiency drop at low loads. Instead the load factor was determined with the Input Power Estimation Method that showed that all motors were operated far below their rated power, thus making this an inefficient energy system. This is a common problem, and an impediment for the directive to achieve its full potential energy savings because the efficiency of motors drops substantially if they are operated below their rated power. The results show that guidelines to avoid motor misapplications is just as important as raising the efficiency of electric motors. In the studied case higher energy savings can be achieved by replacing the tested motors to smaller motors instead of introducing new motors of the same size with a higher efficiency.

A practical and non-invasive method of calculating the efficiency of electric motors could help reduce anthropogenic green house gas emissions by up to 6%. Such a method has been developed using quantitative thermography, however currently, the time required for its implementation is prohibitive. In this thesis, registration and segmentation techniques are applied to the thermograms of the above method, particularly thermograms used in the lumped capacitance method (LCM) and those used to find the average temperature of motors, reducing the time required to process thermograms. The processing of LCM thermograms was completely automated (±5% difference when compared to results obtained manually) while processing of motor thermograms required the location of the motor be provided manually the first time a motor is examined, but was completely automated for subsequent thermo- grams of the same motor (±0.9°C and ±0.6°C difference for non-occluded and occluded motors respectively compared to manual results). / NSERC Chair in Environmental Design Engineering

This diploma thesis deals with comparing the level of physical growth and basic motor skills of preschool children, their motion mode and the conditions for movement activities in two kindergartens located in different municipalities (in a city and in a town). The aim of the study was to determine the level of growth and motor performance of preschool children in relation to the motion mode at their residence. The study included 116 children aged 4-6. The level of physical growth was assessed by measuring somatic characteristics of children (height, weight, BMI). The data extracted from the study were compared to percentile charts. The level of motor performance was assessed by sensory tests. In the case of basic motor skills there was chosen 20 ms run with standing start for the testing of speed capability, for the evaluation of explosive strength abilities was selected jump from the spot with two legs reflection, the testing of explosive strength of the upper limbs was exercised by a ball throw by both right and left hand. At the same time, these tests show the level of motor performance of preschool children. To map the conditions of the motor development of preschool children, an analysis of the conditions of the two municipalities and an analysis of the conditions and the education plan of...

Despite its simple construction, robustness and low manufacturing cost, the application areas of SR motors are remained limited due to the high level of acoustic noise and torque ripple. In this thesis work, two different type of controllers are designed and implemented in order to minimize the acoustic noise and torque ripple which are considered as the major problems of SR motors. In this scope, first the possible acoustic noise sources are investigated. A sliding mode controller is designed and implemented to reduce the shaft torque ripple which is considered as a major source of acoustic noise. The performance of the controller is experimentally tested and it is observed that especially in low speed region reduction of torque ripple is significant. The torque ripple minimization performance of the controller is also tested at different speeds and the acoustic noise levels are recorded simultaneously. Comparing the noise mitigation with the noise reduction the correlation between the acoustic noise and shaft torque ripple is investigated. The results obtained from this investigation indicated that the torque ripple is not a major source of acoustic noise in SR motors. After this finding, radial force which is the other possible acoustic noise source of SRM is taken into consideration. The effects of control parameters on radial force and the motor efficiency are investigated via simulations. With the intuition obtained from this analysis, a switching angle neuro-controller is designed to minimize the peak level of radial forces. The performance of the mentioned controller is verified through noise records under steady state conditions. Regarding to the radial force simulations and the acoustic noise measurements, it is deduced that the radial force is the major source of acoustic noise. On the other hand, another controller is designed and implemented which increases the average torque per ampere value in order to increase the efficiency of the motor. It is seen that this controller has a good effect on increasing the efficiency but does not guarantee to operate at maximum efficiency.

This master’s thesis first deals with the theory concerning induction motor. It briefly desbribes the construction of three-phase induction motors, the generation of tractive force, power flow with loss distribution and also torque characteristic. In the next part an analytical calculation of the parameters of equivalent circuit for an existing induction motor with known dimensions is performed. After the calculation it is possible to find out the rated parameters of the motor, which makes it possible to further compare results with the values obtained by other methods. The next step was to create a model of the motor in RMxprt program, which is later also translated to ANSYS Maxwell 2D model. Simulations were carried out in both interfaces. As the next step the results obtained by the three methods are compared with measured values and also evaluated. The final part of the thesis focuses on the optimization of the magnetic circuit for higher frequencies. Efficiency of the modified induction motor is examined for higher frequencies using RMxprt Optimetrics and this procedure is performed for both default and alternative electrical steel materials.

The master’s thesis introduces various types of electric motors. Overall, it is divided into 6 chapters, which the first deals with special type of electric motors, namely: permanent magnet DC motor with coreless winding, piezoelectric motor and three phase induction motor with solid rotor. For all of these motors are introduced principles, types, advantages, disadvantages and applications. The second part of thesis deals with perspective types of motors, namely: single phase induction motor and reluctance motor. For all of these motors are introduced principles, types, advantages, disadvantages and applications. The third chapter deals with analysis parameters of single phase induction motor. The analysis is performed on a borrowed motor from ATAS company by measurement and verification using simulation program Ansys Maxwell. The fourth part discusses the possibilities of increasing the effectiveness of borrowed electric motor. The following is chapter five, which deals with increasing the efficiency of the motor by changing metal sheets. Results are verified by simulations with Ansys Maxwell and measurements on sample of electric motor. The last part presents electric motor design with new selected electric sheets with lower specific losses, but also with lower magnetic induction.

The PhD presents a combined approach to improving individual car efficiency. An optimal observer, the Extended Kalman Filter, is used to create an efficiency model for the car. Particular attention was paid to handling the asynchronous and redundant nature of the measurement data. A low-cost sensor suite developed to measure data is described. This sensor suite was installed on multiple vehicles to good success. It employsan accelerometer, gps, fuel injector timer, and Vss input to measure all the data necessary to reconstruct the car's state. This observer and sensor suite can be used as the base for any study which requires car efficiency maps, allowing research to proceed without manufacturer supplied data. Once the efficiency map is found, it is then curve-fitted in order to reduce model complexity. The simplified model is then used as a basis for optimal control through Pontryagin's Maximum Principle. Real-world test results are given, both for efficiency mapping, and for optimal control. Detailed discussion of the observer and controller is presented, in order to ease understanding and save implementation time

Ce mémoire de thèse présente une méthode permettant d'améliorer laconduite automobile. Le filtre de Kalman étendu est utilisé pour identifierun modèle de la voiture. Ce filtre est particulièrement étudié afin de prendreen compte la redondance des informations et leur mesure asynchrone.Un ensemble cohérent et bon marché de capteurs - incluant accéléromètres,GPS, temps d'ouverture des injecteurs et vitesse - a été développé et installédans plusieurs véhicules. Ces mesures sont utilisées afin de reconstituer lafonction d'efficacité du moteur. Cette méthodologie peut-être utilisée pourtoute étude requérant la connaissance de cette fonction.La fonction d'efficacité est approchée par une fonction polynomiale etle modèle obtenu est la base d'une optimisation utilisant le principe dumaximum de Pontryagin.Les résultats des tests en condition réelle sont donnés et montrent l'efficicacité de l'observateur et du contrôleur / The PhD presents a combined approach to improving individual car efficiency. An optimal observer, the Extended Kalman Filter, is used to create an efficiency model for the car. Particular attention was paid to handling the asynchronous and redundant nature of the measurement data. A low-cost sensor suite developed to measure data is described. This sensor suite was installed on multiple vehicles to good success. It employsan accelerometer, gps, fuel injector timer, and Vss input to measure all the data necessary to reconstruct the car's state. This observer and sensor suite can be used as the base for any study which requires car efficiency maps, allowing research to proceed without manufacturer supplied data. Once the efficiency map is found, it is then curve-fitted in order to reduce model complexity. The simplified model is then used as a basis for optimal control through Pontryagin's Maximum Principle. Real-world test results are given, both for efficiency mapping, and for optimal control. Detailed discussion of the observer and controller is presented, in order to ease understanding and save implementation time

Energy usage evaluation and condition monitoring for electric machines are important in industry for overall energy savings. Traditionally these functions are realized only for large motors in wired systems formed by communication cables and various types of sensors. The unique characteristics of the wireless sensor networks (WSN) make them the ideal wireless structure for low-cost energy management in industrial plants. This work focuses on developing nonintrusive motor-efficiency-estimation methods, which are essential in the wireless motor-energy-management systems in a WSN architecture that is capable of improving overall energy savings in U.S. industry. This work starts with an investigation of existing motor-efficiency-evaluation methods. Based on the findings, a general approach of developing nonintrusive efficiency-estimation methods is proposed, incorporating sensorless rotor-speed detection, stator-resistance estimation, and loss estimation techniques. Following this approach, two new methods are proposed for estimating the efficiencies of in-service induction motors, using air-gap torque estimation and a modified induction motor equivalent circuit, respectively. The experimental results show that both methods achieve accurate efficiency estimates within ¡À2-3% errors under normal load conditions, using only a few cycles of input voltages and currents. The analytical results obtained from error analysis agree well with the experimental results. Using the proposed efficiency-estimation methods, a closed-loop motor-energy-management scheme for industrial plants with a WSN architecture is proposed. Besides the energy-usage-evaluation algorithms, this scheme also incorporates various sensorless current-based motor-condition-monitoring algorithms. A uniform data interface is defined to seamlessly integrate these energy-evaluation and condition-monitoring algorithms. Prototype wireless sensor devices are designed and implemented to satisfy the specific needs of motor energy management. A WSN test bed is implemented. The applicability of the proposed scheme is validated from the experimental results using multiple motors with different physical configurations under various load conditions. To demonstrate the validity of the measured and estimated motor efficiencies in the experiments presented in this work, an in-depth error analysis on motor efficiency measurement and estimation is conducted, using maximum error estimation, worst-case error estimation, and realistic error estimation techniques. The conclusions, contributions, and recommendations are summarized at the end.