The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform

Vasilija Sarac - One of the best experts on this subject based on the ideXlab platform.

  • STUDY OF PERFORMANCE CHARACTERISTICS OF SINGLE PHASE MotorS
    2016
    Co-Authors: Vasilija Sarac, Goce Stefanov, Goran Cogelja
    Abstract:

    Single phase shaded Pole Motor and permanently split capacitor Motor are analyzed with double-filed revolving theory and method of symmetrical components is used for defining Motor mathematical models. As an output from mathematical models steady-state performance characteristics of both Motors are calculated for different operating regimes. Results from developed mathematical models are verified with experiments. Calculated currents of stator windings from mathematical models are used as input data in numerical models of the Motors analyzed with Finite Element Method (FEM). Magnetic flux density in cross section of the Motors is calculated from numerical Motor models under different operating regimes. Parts of magnetic cores with high flux density are discovered and construction of the Motors is further improved by applying  soft magnetic powders.

  • Simulation Model for Prediction of Transient Performance Characteristics of Single–Phase Shaded Pole Motor
    Journal of Electrical Engineering, 2016
    Co-Authors: Vasilija Sarac, Tatjana Atanasova-pacemska
    Abstract:

    Abstract Paper proposes mathematical model of single phase shaded Pole Motor suitable for analysis of Motor dynamic behavior. Derived mathematical model from d–q reference frame theory is applied at Motor simulation model. Derived simulation model enables analysis of transient performance characteristics of Motor currents, speed and electromagnetic torque under different operating regimes. Obtained results from the simulation are compared with data from analytical calculations based on method of symmetrical components and data from experiment for the purpose of verification of the simulation model. Simulation model is useful for studying the effect of parameters on Motor starting and running characteristics at different types of loads.

  • FEM aided design of performance characteristics of single phase Motors
    2015
    Co-Authors: Vasilija Sarac, Goce Stefanov, Goran Cogelja
    Abstract:

    Paper proposes methodology for calculation of pa-rameters and performance characteristics of single-phase Motors based on double-field revolving theory and method of symmetrical components. Permanently split capacitor Motor and single-phase shaded Pole Motor are investigated and their parameters and performance characteristics are calculated and verified by experiment under different operating regimes. Once, the parameters are calculated they are used as input data in numerical models of the mo-tors based on Finite Element Method (FEM). FEM models are used for calculation of magnetic flux density and its distribution in Motors’ cross-section as well as in the air gap, since these parameters are difficult to be calculated or exactly predicted by analytical methods. Proposed models enable Motor performance under different operating regimes to be analyzed and accurately predicted.

  • different approaches of numerical analysis of electromagnetic phenomena in shaded Pole Motor with application of finite elements method
    URSI International Symposium on Electromagnetic Theory, 2010
    Co-Authors: Vasilija Sarac
    Abstract:

    In this paper is used Finite Element Method-FEM for analysis of electromagnetic quantities of small micro Motor - single phase shaded Pole Motor-SPSPM. FEM is widely used numerical method for solving nonlinear partial differential equations with variable coefficients. For that purpose Motor model is developed with exact geometry and material's characteristics. Two different approaches are applied in FEM analysis of electromagnetic phenomena inside the Motor: magneto-static where all electromagnetic quantities are analysed in exact moment of time meaning frequency f=0 Hz and time-harmonic magnetic approach where the magnetic field inside the machine is time varying, meaning frequency f=50 Hz. Obtained results are presented and compared with available analytical results

  • Comparison between two target functions for optimization of single phase shaded-Pole Motor using method of genetic algorithms
    Journal of Materials Processing Technology, 2005
    Co-Authors: Vasilija Sarac, Milan Cundev, Lidija Petkovska, Goga Cvetkovski
    Abstract:

    Method of genetic algorithms (GAs) has been started to be widely used, as an optimization technique of electrical machines, in the recent years. In this paper the GA method will be applied on the shaded-Pole Motor, aiming towards an improvement of its operational and performance characteristics. The authors develop two new improved Motor models, starting from the basic one. In the first Motor model the electromagnetic torque, as a target function for optimization is suggested, while in the second one the optimization is based on the efficiency factor, used as a target function. The results gained from the both Motor models are analyzed and compared to the basic model. The conclusions regarding the more favorable target function for optimization of a single phase shaded-Pole Motor are presented.

Annette Muetze - One of the best experts on this subject based on the ideXlab platform.

  • Characterization of the Thermal Performances of Low-Cost Sub-Fractional Horsepower BLDC Claw-Pole Motor Designs
    2020 IEEE Energy Conversion Congress and Exposition (ECCE), 2020
    Co-Authors: Stefan Leitner, Thomas Kulterer, Hannes Gruebler, Annette Muetze
    Abstract:

    Automotive auxiliary drives often have to operate over a large temperature range, e.g., between -40 and 135 degrees Celcius. Especially for operation at high ambient temperatures, the understanding of their thermal characteristics is highly important as, e.g., the electromagnetic characteristics of permanent-magnets are strongly temperature-dependent. To this aim, this paper investigates the steady-state and transient thermal performances of different low-cost sub-fractional horsepower single-phase BLDC claw-Pole Motor designs suitable, e.g., for fan applications. Both numerical and experimental analyses are carried out to determine the parameters of a simple thermal equivalent circuit. The studied claw-Pole Motor designs show similar thermal performances, which allows all of them to be used in an automotive auxiliary drive system.

  • Low-Cost BLDC Claw-Pole Motor Design for Fan Applications with Reduced Cogging Torque and Balanced Axial Forces
    2020 IEEE Applied Power Electronics Conference and Exposition (APEC), 2020
    Co-Authors: Stefan Leitner, Hannes Gruebler, Annette Muetze
    Abstract:

    The implementation of skewing to reduce the cogging torque of brushless permanent-magnet Motors usually induces axial magnetic forces which can not only cause noise but also decrease the bearing system’s lifetime. This paper proposes an unconventional outer-rotor BLDC claw-Pole Motor design for sub-fractional horsepower fan applications. Owing to the proposed V-shaped claw-Poles, the cogging torque can be reduced through skewing but, at the same time, the axial magnetic forces are balanced. As opposed to other cogging torque reduction and axial force compensation techniques, the proposed design improvements can be included at no increase to the manufacturing cost since they can be implemented at the stage of punching and deep-drawing the stator steel sheet parts. This is essential for cost-driven automotive auxiliary drive applications such as LED headlight fans, sensor blowers, or seat ventilations. The proposed designs are investigated by means of 3-D finite element analyses and measurements using a rheometer. The findings show that the proposed claw-Pole shapes can achieve both cogging torque reduction of about 50% and axial force compensation. This is illustrated for a 5500rpm 1W example case Motor as part of a low-cost fan application.

  • Cogging Torque Minimization and Performance of the Sub-Fractional HP BLDC Claw-Pole Motor
    IEEE Transactions on Industry Applications, 2019
    Co-Authors: Stefan Leitner, Hannes Gruebler, Annette Muetze
    Abstract:

    Cogging torque reduction measures are hardly applied to low-cost sub-fractional hp brushless direct current (BLDC) Motors, because the additional fabrication operations involved typically increase both the manufacturing complexity and cost significantly. By proposing an innovative punching layout, this paper shows how to minimize the high cogging torque of the mass-produced single-phase outer-rotor BLDC claw-Pole Motor—opposed to conventional cogging torque reduction—with no increase to the manufacturing cost. Systematically, a way is presented in which the selected introduction of auxiliary slots can double the cogging torque fundamental frequency, making stator claw skewing much more effective in reducing the cogging torque; both measures can be included at the stage of punching the steel sheets and subsequent deep-drawing thereof, at no additional cost. A detailed analysis of the effects of the cogging torque reduction measures on the most important Motor performance parameters is conducted. The findings show that, with the exception of a three percentage point reduction in the efficiency, the proposed design can reduce the peak-to-peak cogging torque by 70% in both the simulations and experiments. The reduction in the cogging torque translates into a reduction in the output torque ripple of 17%, ensuring smoother operation especially at low speeds.

  • Cogging Torque Minimization on a Mass-Produced Sub-Fractional Horsepower Brushless Direct Current Claw-Pole Motor
    2018 IEEE Energy Conversion Congress and Exposition (ECCE), 2018
    Co-Authors: Stefan Leitner, Hannes Gruebler, Annette Muetze
    Abstract:

    In mass-produced sub-fractional horsepower brushless direct current drive applications, suboptimal Motor behavior, e.g., high cogging torque and as a result high output torque ripple, is often accepted when low-cost yet properly functioning products can be obtained. This paper systematically shows how to minimize the inherently high cogging torque of the low-cost four-Pole four-slot single-phase outer rotor claw-Pole Motor topology, opposed to conventional cogging torque reduction methods, with no increase in manufacturing cost. First, the selected introduction of auxiliary slots can double the cogging torque fundamental frequency, which halves the optimal skewing angle. Second, owing to the doubled cogging torque fundamental frequency, implementing stator claw skewing is much more efficient and can reduce the cogging torque peak values significantly. Proposed is an innovative claw-Pole Motor design, where the cogging torque reduction methods can be considered at the stage of punching and deep-drawing the steel sheets, at no additional cost. The findings show that, compared with the conventional design, the cogging torque peak-to-peak values have been successfully reduced by 65 % in the simulations and by 67 % in the experiments.

Stefan Leitner - One of the best experts on this subject based on the ideXlab platform.

  • Characterization of the Thermal Performances of Low-Cost Sub-Fractional Horsepower BLDC Claw-Pole Motor Designs
    2020 IEEE Energy Conversion Congress and Exposition (ECCE), 2020
    Co-Authors: Stefan Leitner, Thomas Kulterer, Hannes Gruebler, Annette Muetze
    Abstract:

    Automotive auxiliary drives often have to operate over a large temperature range, e.g., between -40 and 135 degrees Celcius. Especially for operation at high ambient temperatures, the understanding of their thermal characteristics is highly important as, e.g., the electromagnetic characteristics of permanent-magnets are strongly temperature-dependent. To this aim, this paper investigates the steady-state and transient thermal performances of different low-cost sub-fractional horsepower single-phase BLDC claw-Pole Motor designs suitable, e.g., for fan applications. Both numerical and experimental analyses are carried out to determine the parameters of a simple thermal equivalent circuit. The studied claw-Pole Motor designs show similar thermal performances, which allows all of them to be used in an automotive auxiliary drive system.

  • Low-Cost BLDC Claw-Pole Motor Design for Fan Applications with Reduced Cogging Torque and Balanced Axial Forces
    2020 IEEE Applied Power Electronics Conference and Exposition (APEC), 2020
    Co-Authors: Stefan Leitner, Hannes Gruebler, Annette Muetze
    Abstract:

    The implementation of skewing to reduce the cogging torque of brushless permanent-magnet Motors usually induces axial magnetic forces which can not only cause noise but also decrease the bearing system’s lifetime. This paper proposes an unconventional outer-rotor BLDC claw-Pole Motor design for sub-fractional horsepower fan applications. Owing to the proposed V-shaped claw-Poles, the cogging torque can be reduced through skewing but, at the same time, the axial magnetic forces are balanced. As opposed to other cogging torque reduction and axial force compensation techniques, the proposed design improvements can be included at no increase to the manufacturing cost since they can be implemented at the stage of punching and deep-drawing the stator steel sheet parts. This is essential for cost-driven automotive auxiliary drive applications such as LED headlight fans, sensor blowers, or seat ventilations. The proposed designs are investigated by means of 3-D finite element analyses and measurements using a rheometer. The findings show that the proposed claw-Pole shapes can achieve both cogging torque reduction of about 50% and axial force compensation. This is illustrated for a 5500rpm 1W example case Motor as part of a low-cost fan application.

  • Cogging Torque Minimization and Performance of the Sub-Fractional HP BLDC Claw-Pole Motor
    IEEE Transactions on Industry Applications, 2019
    Co-Authors: Stefan Leitner, Hannes Gruebler, Annette Muetze
    Abstract:

    Cogging torque reduction measures are hardly applied to low-cost sub-fractional hp brushless direct current (BLDC) Motors, because the additional fabrication operations involved typically increase both the manufacturing complexity and cost significantly. By proposing an innovative punching layout, this paper shows how to minimize the high cogging torque of the mass-produced single-phase outer-rotor BLDC claw-Pole Motor—opposed to conventional cogging torque reduction—with no increase to the manufacturing cost. Systematically, a way is presented in which the selected introduction of auxiliary slots can double the cogging torque fundamental frequency, making stator claw skewing much more effective in reducing the cogging torque; both measures can be included at the stage of punching the steel sheets and subsequent deep-drawing thereof, at no additional cost. A detailed analysis of the effects of the cogging torque reduction measures on the most important Motor performance parameters is conducted. The findings show that, with the exception of a three percentage point reduction in the efficiency, the proposed design can reduce the peak-to-peak cogging torque by 70% in both the simulations and experiments. The reduction in the cogging torque translates into a reduction in the output torque ripple of 17%, ensuring smoother operation especially at low speeds.

  • Cogging Torque Minimization on a Mass-Produced Sub-Fractional Horsepower Brushless Direct Current Claw-Pole Motor
    2018 IEEE Energy Conversion Congress and Exposition (ECCE), 2018
    Co-Authors: Stefan Leitner, Hannes Gruebler, Annette Muetze
    Abstract:

    In mass-produced sub-fractional horsepower brushless direct current drive applications, suboptimal Motor behavior, e.g., high cogging torque and as a result high output torque ripple, is often accepted when low-cost yet properly functioning products can be obtained. This paper systematically shows how to minimize the inherently high cogging torque of the low-cost four-Pole four-slot single-phase outer rotor claw-Pole Motor topology, opposed to conventional cogging torque reduction methods, with no increase in manufacturing cost. First, the selected introduction of auxiliary slots can double the cogging torque fundamental frequency, which halves the optimal skewing angle. Second, owing to the doubled cogging torque fundamental frequency, implementing stator claw skewing is much more efficient and can reduce the cogging torque peak values significantly. Proposed is an innovative claw-Pole Motor design, where the cogging torque reduction methods can be considered at the stage of punching and deep-drawing the steel sheets, at no additional cost. The findings show that, compared with the conventional design, the cogging torque peak-to-peak values have been successfully reduced by 65 % in the simulations and by 67 % in the experiments.

Kenji Endo - One of the best experts on this subject based on the ideXlab platform.

  • sensorless torque control of salient Pole synchronous Motor at zero speed operation
    IEEE Transactions on Power Electronics, 1999
    Co-Authors: Takashi Aihara, Akihide Mashimo, Takao Yanase, Akio Toba, Kenji Endo
    Abstract:

    A position and speed sensorless control using the counter electromotive force of a permanent-magnet Motor (PM) debases the control performance at a low speed. We propose a controllable system at full speed, including a zero speed using saliency. At low speed, the sensorless control is made by observing a current ripple at a time when alternating voltage has been applied to a salient-Pole Motor. Also, for discriminating the S and N Poles of the magnet, magnetic saturation is used. A device has been applied to the Motor rotor to allow the magnetic saturation to come about easily. Furthermore, at a time of high speed, drive at a full-speed range has been accomplished by switching smoothly over to a sensorless driving system making use of counter electromotive force. All algorithms are implemented by software, and this system can operate successively from starting to high-speed operation. The paper discusses the operational principles at a low speed, analysis and experimental results, the control scheme, how to changeover the control mode at high speed, and the experimental results.

  • sensor less torque control of salient Pole synchronous Motor at zero speed operation
    Applied Power Electronics Conference, 1997
    Co-Authors: Takashi Aihara, Akihide Mashimo, Takao Yanase, Akio Toba, Kenji Endo
    Abstract:

    A position and speed sensorless control scheme using the counter EMF of PM Motors debases the control performance at low speed. Here, the authors propose a controllable system at full speed, including zero speed, using saliency. At low speed, sensorless control is performed by observing a current ripple at a time when an alternating voltage has been applied to the salient-Pole Motor. Also, for discriminating the S and N Poles of the magnet, magnetic saturation is used. A device has been applied to the Motor rotor to allow the magnetic saturation to be brought about easily. Further, at times of high speed, a full speed range drive has been accomplished by switching smoothly over to a sensorless driving system, making use of the counter EMF.

Goga Cvetkovski - One of the best experts on this subject based on the ideXlab platform.

  • Comparison between two target functions for optimization of single phase shaded-Pole Motor using method of genetic algorithms
    Journal of Materials Processing Technology, 2005
    Co-Authors: Vasilija Sarac, Milan Cundev, Lidija Petkovska, Goga Cvetkovski
    Abstract:

    Method of genetic algorithms (GAs) has been started to be widely used, as an optimization technique of electrical machines, in the recent years. In this paper the GA method will be applied on the shaded-Pole Motor, aiming towards an improvement of its operational and performance characteristics. The authors develop two new improved Motor models, starting from the basic one. In the first Motor model the electromagnetic torque, as a target function for optimization is suggested, while in the second one the optimization is based on the efficiency factor, used as a target function. The results gained from the both Motor models are analyzed and compared to the basic model. The conclusions regarding the more favorable target function for optimization of a single phase shaded-Pole Motor are presented.

  • Dynamic Evaluation of Shaded Pole Motor models by Using Method of Genetic Algorithm
    2004
    Co-Authors: Vasilija Sarac, Lidija Petkovska, Goga Cvetkovski
    Abstract:

    In this paper, an extended analysis of three different models of a single phase shaded Pole Motor is carried out. starting with basic model and by using well established optimization method of Genetic algorithm (GA)two optimized Motor models are derived. A special emphasis is put on development of appropriate models of the shaded Pole Motor for application of particular analysis method. The magnetic field analysis is based on Finite Element Method (FEM). The optimized Motor models show improvements regarding the saturation of particular parts of magnetic core. The dynamic analysis of the Motor is performed on the basis of dynamic characteristics determined by using Matlab/Simulink Method (MSM). Form this analysis, the shaded Pole Motor basic model and two new derived optimized models are discussed and evaluated.