energies-logo

Journal Browser

Journal Browser

Special Issue "Design and Application of Electrical Machines"

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "A6: Electric Vehicles".

Deadline for manuscript submissions: closed (25 August 2021) | Viewed by 14264

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editors

Prof. Dr. Ryszard Palka
E-Mail Website
Guest Editor
Department of Electrical Engineering, West Pomeranian University of Technology, 70-310 Szczecin, Poland
Interests: electrical machines; numerical field calculations; optimization of electromagnetic fields; high temperature superconductivity: superconducting machines; superconducting bearings
Special Issues, Collections and Topics in MDPI journals
Dr. Marcin Wardach
E-Mail Website
Guest Editor
Faculty of Electrical Engineering, Department of Power Systems and Electrical Drives, West Pomeranian University of Technology in Szczecin, al. Piastów 17, 70-310 Szczecin, Poland
Interests: electrical machines; numerical field calculations; optimization of electromagnetic fields; renewable energy technologies; electrical engineering; power generation
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The Guest Editors are inviting you to submit papers to a Special Issue of Energies on the subject of “Design and Application of Electrical Machines”.

There is little need to prove the importance of the subject matter. Electrical machines are the most important components of both the industrial and the commercial world. They are at the heart of the new industrial revolution brought forth by the development of electromobility and renewable energy systems. Today’s electric motors must meet the most stringent requirements of reliability, availability, and high efficiency in order to match (and exceed!) the useful lifetime of power electronics in the complex system application and to compete in the market under ever-increasing pressure to deliver the highest performance criteria.

Today, thanks to the application of highly efficient numerical algorithms running on high-performance computers, it is possible to design electric machines and entire drive systems faster and at a lower cost. At the same time, progress in the field of material science and technology enables the development of ever more complex motor designs and topologies.

Therefore, the purpose of this Special Issue is to contribute to the development of electric machines. We encourage scientists and application engineers to present the results of their research in the field of design and application of electric machines from the smallest ones with powers up to several watts, to the largest—at megawatt power. We are pleased to accept original research as well as review articles.

Topics of interest for publication include but are not limited to:

  • Simulation tools, modeling, and analysis of electrical machines;
  • New design methods of electrical machines;
  • Optimization of electrical machines;
  • Electrical machines for EVs and HEVs;
  • Power electronics used for electrical machines;
  • Supply and control of electrical machines;
  • New technologies, materials, devices, and systems for electrical machines;
  • Linear drives for transportation.

Prof. Dr. Ryszard Palka
Dr. Marcin Wardach
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2200 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • electrical machines
  • numerical field calculations
  • optimization of electromagnetic fields
  • electrical vehicles
  • permanent magnet machines
  • hybrid excited machines
  • wind power energy

Published Papers (19 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Editorial

Jump to: Research, Review, Other

Editorial
Design and Application of Electrical Machines
Energies 2022, 15(2), 523; https://doi.org/10.3390/en15020523 - 12 Jan 2022
Viewed by 282
Abstract
Design and Application of Electrical Machines is a Special Issue of Energies [...] Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)

Research

Jump to: Editorial, Review, Other

Article
Experimental Validations of Hybrid Excited Linear Flux Switching Machine
Energies 2021, 14(21), 7274; https://doi.org/10.3390/en14217274 - 03 Nov 2021
Cited by 3 | Viewed by 354
Abstract
Linear Flux Switching Machines (LFSMs) possess the capability to generate adhesive thrust force, thus problems associated with conventional rotatory electric machines and mechanical conversion assemblies can be eliminated. Additionally, the unique features of high force/power density, efficiency, and a robust secondary structure make [...] Read more.
Linear Flux Switching Machines (LFSMs) possess the capability to generate adhesive thrust force, thus problems associated with conventional rotatory electric machines and mechanical conversion assemblies can be eliminated. Additionally, the unique features of high force/power density, efficiency, and a robust secondary structure make LFSMs a suitable candidate for linear motion applications. However, deficiency of controllable air-gap flux, risk of PM demagnetization, and increasing cost of rare earth PM materials in case of PMLFSMs, and inherent low thrust force capability of Field Excited LFSMs compels researchers to investigate new hybrid topologies. In this paper, a novel Double-Sided Hybrid Excited LFSM (DSHELFSM) with all three excitation sources, i.e., PMs, DC, and AC windings confined to short moving primary and segmented secondary providing short flux paths is designed, investigated, and optimized. Secondly, unequal primary tooth width optimization and additional end-teeth at all four corners of the primary equip proposed design with balanced magnetic circuit and reduced end-effect and thrust force ripples. Thirdly, the measured experimental results of the manufactured proposed machine prototype are compared with corresponding simulated model results and shows good agreements, thus validating the theoretical study. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
The Choice of the Optimal Number of Discs in an MR Clutch from the Viewpoint of Different Criteria and Constraints
Energies 2021, 14(21), 6888; https://doi.org/10.3390/en14216888 - 20 Oct 2021
Cited by 2 | Viewed by 425
Abstract
This paper focuses on magnetorheological clutches (MR clutches) with a disc structure that can be designed as one-disc or multi-disc clutches (number of discs: N = 1, N > 2). The main goal of the paper is to compare their overall dimensions (lengths [...] Read more.
This paper focuses on magnetorheological clutches (MR clutches) with a disc structure that can be designed as one-disc or multi-disc clutches (number of discs: N = 1, N > 2). The main goal of the paper is to compare their overall dimensions (lengths and radii), masses, volumes, and characteristic factors—torque per mass ratio and torque per volume ratio for MR clutches that develop the same given clutching torque Tc but differ in the number of discs (it is assumed that the number of discs of the primary member varies from one to four). This analysis develops charts and guidelines that will allow designers to choose the appropriate number of discs from the view point of various criteria, and with various limitations regarding geometry, geometric proportions, mass, volume, or restrictions on the amount of active materials used in the manufacturing process. The limitations on the active materials used are of particular importance in the case of mass production. Our methodology uses a comparative study, which can also be used when comparing design solutions of other electromechanical converters. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Design and Optimization of a High-Speed Switched Reluctance Motor
Energies 2021, 14(20), 6733; https://doi.org/10.3390/en14206733 - 16 Oct 2021
Cited by 3 | Viewed by 561
Abstract
Currently, one of the most used motor types for high-speed applications is the permanent-magnet synchronous motor. However, this type of machine has high costs and rare earth elements are needed for its production. For these reasons, permanent-magnet-free alternatives are being sought. An overview [...] Read more.
Currently, one of the most used motor types for high-speed applications is the permanent-magnet synchronous motor. However, this type of machine has high costs and rare earth elements are needed for its production. For these reasons, permanent-magnet-free alternatives are being sought. An overview of high-speed electrical machines has shown that the switched reluctance motor is a possible alternative. This paper deals with design and optimization of this motor, which should achieve the same output power as the existing high-speed permanent-magnet synchronous motor while maintaining the same motor volume. The paper presents the initial design of the motor and the procedure for analyses performed using analytical and finite element methods. During the electromagnetic analysis, the influence of motor geometric parameters on parameters such as: maximum current, average torque, torque ripple, output power, and losses was analyzed. The analysis of windage losses was performed by analytical calculation. Based on the results, it was necessary to create a cylindrical rotor shape. The rotor modification method was chosen based on mechanical analysis. Using thermal analysis, the design was modified to meet thermal limits. The result of the work was a design that met all requirements and limits. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Experimental Investigation of a Double-Acting Vane Pump with Integrated Electric Drive
Energies 2021, 14(18), 5949; https://doi.org/10.3390/en14185949 - 18 Sep 2021
Cited by 2 | Viewed by 808
Abstract
The article presents an innovative design solution of a balanced vane pump integrated with an electric motor that has been developed by the authors. The designed and constructed bench, which enables testing of the system: power supply, converter, ntegrated motor—pump assembly and hydraulic [...] Read more.
The article presents an innovative design solution of a balanced vane pump integrated with an electric motor that has been developed by the authors. The designed and constructed bench, which enables testing of the system: power supply, converter, ntegrated motor—pump assembly and hydraulic load at different motor speeds and different pressures in the hydraulic system, is described. The electromagnetic and hydraulic processes in the motor-pump unit are investigated, and new, previously unpublished, results of experimental studies at steady and dynamic states are presented. The results of the study showed good dynamics of the integrated motor-pump assembly and proved its suitability to control the pump flow rate, and thus, the speed of the hydraulic cylinder or the speed of the hydraulic motor. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Prediction of Electromagnetic Characteristics in Stator End Parts of a Turbo-Generator Based on MLP and SVR
Energies 2021, 14(18), 5908; https://doi.org/10.3390/en14185908 - 17 Sep 2021
Cited by 1 | Viewed by 459
Abstract
In order to study the multiple restricted factors and parameters of the eddy current loss of generator end structures, both the multi-layer perceptron (MLP) and support vector regression (SVR) are used to study and predict the mechanism of the synergistic effect of metal [...] Read more.
In order to study the multiple restricted factors and parameters of the eddy current loss of generator end structures, both the multi-layer perceptron (MLP) and support vector regression (SVR) are used to study and predict the mechanism of the synergistic effect of metal shield conductivity, relative permeability of clamping plates and structural characteristics of eddy current losses. Based on the eddy current losses of generator end structures under different metal shielding thicknesses and electromagnetic properties, the calculation accuracy of the MLP and SVR is compared. The prediction method gives an effective means for the complex design of the end region of the generator, which reduces the effort of the designers. It also promotes the design efficiency of the electrical generator. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Application of the Harmonic Balance Method for Spatial Harmonic Interactions Analysis in Axial Flux PM Generators
Energies 2021, 14(17), 5570; https://doi.org/10.3390/en14175570 - 06 Sep 2021
Cited by 2 | Viewed by 742
Abstract
In this paper, an application of the Harmonic Balance Method (HBM) for analysis of Axial Flux Permanent Magnet Generator (AFPMG) is carried out. Particular attention was paid to development of mathematical model equations allowing to estimate the machine properties, without having to use [...] Read more.
In this paper, an application of the Harmonic Balance Method (HBM) for analysis of Axial Flux Permanent Magnet Generator (AFPMG) is carried out. Particular attention was paid to development of mathematical model equations allowing to estimate the machine properties, without having to use quantitative solutions. The methodology used here allowed for precise determination of Fourier spectra with respect to winding currents and electromagnetic torque (both quantitatively and qualitatively) in steady state operation. Analyses of space harmonic interaction in steady states were presented for the three-phase AFPMG. Satisfactory convergence was between the results of calculations and measurements which confirmed the initial assumption that the developed circuit models of AFPMG are sufficiently accurate and can be useful in the diagnostic analyses, tests and the final stages of the design process. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Lumped Parameter Model and Electromagnetic Performance Analysis of a Single-Sided Variable Flux Permanent Magnet Linear Machine
Energies 2021, 14(17), 5494; https://doi.org/10.3390/en14175494 - 03 Sep 2021
Cited by 2 | Viewed by 561
Abstract
A new Single-sided Variable Flux Permanent Magnet Linear Machine with flux bridge in mover core is proposed in this paper. The flux bridge prevents the leakage flux from the mover and converts it into flux linkage, which greatly influences the performance of the [...] Read more.
A new Single-sided Variable Flux Permanent Magnet Linear Machine with flux bridge in mover core is proposed in this paper. The flux bridge prevents the leakage flux from the mover and converts it into flux linkage, which greatly influences the performance of the machine. First, a lumped parameter model is used to find the suitable coil combination and no-load flux linkage of the proposed machine, which greatly reduces the computational time and drive storage. Secondly, the proposed machine replaces the expensive rare earth permanent magnets with ferrite magnets and provides improved flux controlling capability under variable excitation currents. Multivariable geometric optimization is utilized to optimize the leading design parameters like split ratio, stator pole width, width and height of permanent magnet, flux bridge width, the width of mover’s tooth, and stator slot depth at constant electric and magnetic loading. The optimized design increases the flux linkage by 44.11%, average thrust force by 35%, thrust force density by 35.02%, minimizes ripples in thrust force by 23%, and detent force by 87.5%. Furthermore, the results obtained by 2D analysis are verified by 3D analysis. Thermal analysis is done to set the operating limit of the proposed machine. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Analysis and Experimental Verification of the Demagnetization Vulnerability in Various PM Synchronous Machine Configurations for an EV Application
Energies 2021, 14(17), 5447; https://doi.org/10.3390/en14175447 - 01 Sep 2021
Cited by 4 | Viewed by 932
Abstract
Safety is a critical feature for all passenger vehicles, making fail–safe operation of the traction drive system highly important. Increasing demands for traction drives that can operate in challenging environments over wide constant power speed ranges expose permanent magnet (PM) machines to conditions [...] Read more.
Safety is a critical feature for all passenger vehicles, making fail–safe operation of the traction drive system highly important. Increasing demands for traction drives that can operate in challenging environments over wide constant power speed ranges expose permanent magnet (PM) machines to conditions that can cause irreversible demagnetization of rotor magnets. In this paper, a comprehensive analysis of the demagnetization vulnerability in PM machines for an electric vehicle (EV) application is presented. The first half of the paper presents rotor demagnetization characteristics of several different PM machines to investigate the impact of different design configurations on demagnetization and to identify promising machine geometries that have higher demagnetization resistance. Experimental verification results of rotor demagnetization in an interior PM (IPM) machine are presented in the latter half of the paper. The experimental tests were carried out on a specially designed locked-rotor test setup combined with closed-loop magnet temperature control. Experimental results confirm that both local and global demagnetization damage can be accurately predicted by time-stepped finite element (FE) analysis. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Research on Electromagnetic Field, Eddy Current Loss and Heat Transfer in the End Region of Synchronous Condenser with Different End Structures and Material Properties
Energies 2021, 14(15), 4636; https://doi.org/10.3390/en14154636 - 30 Jul 2021
Cited by 3 | Viewed by 588
Abstract
Aiming at the problem of end structure heating caused by the excessive eddy current loss of large synchronous condensers used in ultra-high voltage (UHV) power transmission, combined with the actual operation characteristics of the synchronous condenser, a three-dimensional transient electromagnetic field physical model [...] Read more.
Aiming at the problem of end structure heating caused by the excessive eddy current loss of large synchronous condensers used in ultra-high voltage (UHV) power transmission, combined with the actual operation characteristics of the synchronous condenser, a three-dimensional transient electromagnetic field physical model is established, and three schemes for adjusting the end structure of the condenser under rated condition are researched. The original structure has a copper shield and a steel clamping plate. Scheme 1 has no copper shield but has a steel clamping plate. Scheme 2 has no copper shield but has an aluminum clamping plate. By constructing a three-dimensional fluid–solid coupling heat transfer model in the end of the synchronous condenser, and giving the basic assumptions and boundary conditions, the eddy current loss of the structure calculated by the three schemes is applied to the end region of the synchronous condenser as the heat source, and the velocity distribution of the cooling medium and the temperature distribution of each structure under the three different schemes are obtained. In order to verify the rationality of the numerical analysis model and the effectiveness of the calculation method, the temperature of the inner edge of the copper shield in the end of the synchronous condenser is measured, and the temperature calculation results are consistent with the temperature measurement results, which provides a theoretical basis for the electromagnetic design, structural optimization, ventilation and cooling of the synchronous condenser. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Transient System Model for the Analysis of Structural Dynamic Interactions of Electric Drivetrains
Energies 2021, 14(4), 1108; https://doi.org/10.3390/en14041108 - 19 Feb 2021
Cited by 1 | Viewed by 637
Abstract
In electric drivetrains, the traction machines are often coupled to a gear transmission. For the noise and vibration analysis of such systems, linearised system models in the frequency domain are commonly used. In this paper, a system approach in the time domain is [...] Read more.
In electric drivetrains, the traction machines are often coupled to a gear transmission. For the noise and vibration analysis of such systems, linearised system models in the frequency domain are commonly used. In this paper, a system approach in the time domain is introduced, which gives the advantage of analysing the transient behaviour of an electric drivetrain. The focus in this paper is on the dynamic gear model. Finally, the modelling approach is applied to an exemplary drivetrain, and the results are discussed. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Influence of the Preformed Coil Design on the Thermal Behavior of Electric Traction Machines
Energies 2021, 14(4), 959; https://doi.org/10.3390/en14040959 - 11 Feb 2021
Cited by 2 | Viewed by 753
Abstract
Preformed coils are used in electrical machines to improve the copper slot fill factor. A higher utilization of the machine can be realized. The improvement is a result of both, low copper losses due to the increased slot fill factor and an improved [...] Read more.
Preformed coils are used in electrical machines to improve the copper slot fill factor. A higher utilization of the machine can be realized. The improvement is a result of both, low copper losses due to the increased slot fill factor and an improved heat transition out of the slot. In this study, the influence of these two aspects on the operational improvement of the machine is studied. Detailed simulation models allow a separation of the two effects. A preform wound winding in comparison to a round wire winding is studied. Full machine prototypes as well as motorettes of the two designs are built up. Thermal finite element models of the stator slot are developed and parameterized with the help of motorette microsections. The resulting thermal lumped parameter model is enlarged to represent the entire electric machine. Electromagnetic finite element models for loss calculation and the thermal lumped parameter models are parameterized using test bench measurements. The developed models show very good agreement in comparison to the test bench evaluation. The study indicates that both, the improvements in the heat transition path and the advantages of the reduced losses in the slot contribute to the improved operational range in dependency of the studied operational point. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Selected Aspects of Decreasing Weight of Motor Dedicated to Wheel Hub Assembly by Increasing Number of Magnetic Poles
Energies 2021, 14(4), 917; https://doi.org/10.3390/en14040917 - 09 Feb 2021
Cited by 4 | Viewed by 901
Abstract
Decreasing the mass of a wheel hub motor by improving the design of a motor’s electromagnetic circuit is discussed in this paper. The authors propose to increase the number of magnetic pole pairs. They present possibilities of mass reduction obtained by these means. [...] Read more.
Decreasing the mass of a wheel hub motor by improving the design of a motor’s electromagnetic circuit is discussed in this paper. The authors propose to increase the number of magnetic pole pairs. They present possibilities of mass reduction obtained by these means. They also analyze the impact of design changes on losses and temperature distribution in motor elements. Lab tests of a constructed prototype, as well as elaborated conjugate thermal-electromagnetic models of the prototype motor and modified motor (i.e., motor with increased number of magnetic poles) were used in the investigation. Simulation models were verified by tests on the prototype. Results of calculations for two motors, differing by the number of pair poles, were compared over a wide operational range specific to the motor application in the electric traction. A detailed analysis of the operational range for these motors was also made. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Nonlinear Digital Simulation Models of Switched Reluctance Motor Drive
Energies 2020, 13(24), 6715; https://doi.org/10.3390/en13246715 - 19 Dec 2020
Cited by 2 | Viewed by 678
Abstract
The paper deals with nonlinear simulation models of a drive consisting of the four-phase 8/6 doubly salient switched reluctance motor (SRM), the four-phase dissymmetric bridge power converter and the closed-cycle rotor speed control strategy carried out by the pulse width modulation (PWM) with [...] Read more.
The paper deals with nonlinear simulation models of a drive consisting of the four-phase 8/6 doubly salient switched reluctance motor (SRM), the four-phase dissymmetric bridge power converter and the closed-cycle rotor speed control strategy carried out by the pulse width modulation (PWM) with variable angle and combined control scheme with the PI algorithm. All presented considerations are based on a MATLAB-SIMULINK platform. The nonlinear mathematical model of the analyzed SRM drive was obtained as a combination of the two dimensional (2D) finite element model (FEM) of the motor and the nonlinear model of the electrical network of the power supply circuit. The main model and its seven sub-modules, such as the controller module, one phase simulation module, rotor position angle transformation module, power system module, phase current operation module, “subsystem” module, and electromagnetic torque of one phase operation module, are described. MATLAB functions store the magnetization curves data of the motor obtained by the 2D FEM electromagnetic field calculations, as well as the data of magnetic co-energy curves of the motor calculated from the magnetization curves. The 2D specimen insert method is adopted in MATLAB functions for operating the flux linkage and the magnetic co-energy at the given phase current and rotor position. The phase current waveforms obtained during simulations match with the tested experimentally phases current waveforms at the same rotor speed and the same load basically. The simulated rotor speed curves also agree with the experimental rotor speed curves. This means that the method of suggested nonlinear simulation models of the analyzed SRM drive is correct, and the model is accurate. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Effect of Demagnetization on a Consequent Pole IPM Synchronous Generator
Energies 2020, 13(23), 6371; https://doi.org/10.3390/en13236371 - 02 Dec 2020
Cited by 4 | Viewed by 845
Abstract
The design and analysis of a permanent magnet synchronous generator (PMSG) are presented. The interior permanent magnet (IPM) rotor was designed asymmetric and with the consequent pole approach. The basis for the design was a series-produced three-phase induction motor (IM) and neodymium iron [...] Read more.
The design and analysis of a permanent magnet synchronous generator (PMSG) are presented. The interior permanent magnet (IPM) rotor was designed asymmetric and with the consequent pole approach. The basis for the design was a series-produced three-phase induction motor (IM) and neodymium iron boron (Nd-Fe-B) cuboid magnets were used for the design. For the partial demagnetization analysis, some of the magnets were extracted and the results are compared with the finite element analysis (FEA). Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Faulty Synchronization of Salient Pole Synchronous Hydro Generator
Energies 2020, 13(20), 5491; https://doi.org/10.3390/en13205491 - 20 Oct 2020
Cited by 6 | Viewed by 742
Abstract
This article presents the simulation results of hydro generator faulty synchronization during connection to the grid for various voltage phase shift changes in a full range (−180°; 180°). A field-circuit model of salient pole synchronous hydro generator was used to perform the calculation [...] Read more.
This article presents the simulation results of hydro generator faulty synchronization during connection to the grid for various voltage phase shift changes in a full range (−180°; 180°). A field-circuit model of salient pole synchronous hydro generator was used to perform the calculation results. It was verified using the measured no-load and three-phase short-circuit characteristics. This model allowed observing the physical phenomena existing in the investigated machine, especially in the rotor which was hardly accessible for measurement. The presented analysis shows the influence of faulty synchronization on the power system stability and the construction components which are the most vulnerable to damage. From a mechanical point of view, the most dangerous case was for the voltage phase shift equal to −120°, and this case was analyzed in detail. Great emphasis was placed on the following physical quantities: electromagnetic torque, stator current, stator voltage, rotor current, current in rotor bars, and active and reactive power. The physical quantities existing during faulty synchronization were compared with a three-phase sudden short-circuit state. From this comparison, we selected the values of physical quantities that should be taken into account during design of new hydro generators to withstand the greatest possible threats during long-term work. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Article
Analysis of Open-Circuit Fault in Fault-Tolerant BLDC Motors with Different Winding Configurations
Energies 2020, 13(20), 5321; https://doi.org/10.3390/en13205321 - 13 Oct 2020
Cited by 5 | Viewed by 607
Abstract
In this study, tests were carried out on a brushless permanent magnet DC motor with different winding configurations. Three configurations were compared: star, delta and combined star–delta. A mathematical model was constructed for the motor, taking into account the different winding configurations. An [...] Read more.
In this study, tests were carried out on a brushless permanent magnet DC motor with different winding configurations. Three configurations were compared: star, delta and combined star–delta. A mathematical model was constructed for the motor, taking into account the different winding configurations. An analysis of the operation of the motor in the different configurations was performed, based on numerical calculations. The use of different winding configurations affects the properties of the motor. This is significant in the case of the occurrence of various fault states. Based on numerical calculations, an analysis of an open-circuit fault in one of the phases of the motor was performed. Fast Fourier Transform—FFT analysis of the artificial neutral-point voltage was used for the detection of fault states. The results were verified by tests carried out under laboratory conditions. It was shown that the winding configuration has an impact on the behaviour of the motor in the case of an open circuit in one of the phases. The classical star configuration is the worst of the possible arrangements. The most favourable in this respect is the delta configuration. In the case of the combined star–delta configuration, the consequences of the fault depend on the location of the open circuit. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Graphical abstract

Review

Jump to: Editorial, Research, Other

Review
Modern Hybrid Excited Electric Machines
Energies 2020, 13(22), 5910; https://doi.org/10.3390/en13225910 - 12 Nov 2020
Cited by 5 | Viewed by 777
Abstract
The paper deals with the overview of different designs of hybrid excited electrical machines, i.e., those with conventional permanent magnets excitation and additional DC-powered electromagnetic systems in the excitation circuit. The paper presents the most common topologies for this type of machines found [...] Read more.
The paper deals with the overview of different designs of hybrid excited electrical machines, i.e., those with conventional permanent magnets excitation and additional DC-powered electromagnetic systems in the excitation circuit. The paper presents the most common topologies for this type of machines found in the literature—they were divided according to their electrical, mechanical and thermal properties. Against this background, the designs of hybrid excited machines that were the subject of scientific research of the authors are presented. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Other

Creative
Development and Verification of a Simulation Model for 120 kW Class Electric AWD (All-Wheel-Drive) Tractor during Driving Operation
Energies 2020, 13(10), 2422; https://doi.org/10.3390/en13102422 - 12 May 2020
Cited by 10 | Viewed by 1088
Abstract
This study was conducted to develop a simulation model of a 120 kW class electric all-wheel-drive (AWD) tractor and verify the model by comparing the measurement and simulation results. The platform was developed based on the power transmission system, including batteries, electric motors, [...] Read more.
This study was conducted to develop a simulation model of a 120 kW class electric all-wheel-drive (AWD) tractor and verify the model by comparing the measurement and simulation results. The platform was developed based on the power transmission system, including batteries, electric motors, reducers, wheels, and a charging system composed of a generator, an AC/DC converter, and chargers on each axle. The data measurement system was installed on the platform, consisting of an analog (current) and a digital part (rotational speed of electric motors and voltage and SOC (state of charge) level of batteries) by a CAN (controller area network) bus. The axle torque was calculated using the current and torque curves of the electric motor. The simulation model was developed by 1D simulation software and used axle torque and vehicle velocity data to create the simulation conditions. To compare the results of the simulation, a driving test using the platform was performed at a ground speed of 10 km/h in off- and on-road conditions. The similarities between the results were analyzed using statistical software and we found no significant difference in axle torque data. The simulation model was considered to be highly reliable given the change rate and average value of the SOC level. Using the simulation model, the workable time of driving operation was estimated to be about six hours and the workable time of plow tillage was estimated to be about 2.4 h. The results showed that the capacity of the battery is slightly low for plow tillage. However, in future studies, the electric AWD tractor performance could be improved through battery optimization through simulation under various conditions. Full article
(This article belongs to the Special Issue Design and Application of Electrical Machines)
Show Figures

Figure 1

Back to TopTop