Analysis Of Electrical Machines Research Articles

The Comparative Analysis of Permanent Magnet Electric Machines with Integer and Fractional Number of Slots per Pole and Phase

The comparison of permanent magnet motors with integer and fractional number of slots per pole and phase was made. The torque developed by the motor and the torque ripples level were chosen as the major criterions. The comparison was made according to the results of equations of numerical calculation of magnetic field in active motors volumes using the finite element analysis. The recommendations on the choice of the most suitable option are given.

Power Loss Analysis in Thermal Design of Permanent Magnet Machines – A Review

This paper reviews recent developments in power loss analysis applicable, but not limited to, the thermal design of permanent-magnet machines. Accurate and computationally efficient loss prediction is an essential element in the thermal analysis of electrical machines and has become an increasingly important part of the machine design process. The continuous drive toward “more electric” technologies has resulted in a need for a more comprehensive and detailed design approach, where various multiphysics and multidisciplinary effects are accounted for. This “design for application” methodology relies strongly on the advancements and evolution of the existing theoretical and experimental design techniques to satisfy the evermore-demanding machine design requirements. The thermal behavior and efficiency of the power conversion are essential performance measures in the “design for application” approach. An overview of the challenges and limitations regarding power loss analysis in the context of the thermal design of electrical machines is provided in this paper. All of the major loss components associated with the active parts of a machine assembly are discussed.

Comparison and Analysis of Magnetic-Geared Permanent Magnet Electrical Machine at No-Load

Abstract Magnetic-geared permanent magnet (MGPM) electrical machine is a new type of machine by incorporating magnetic gear into PM electrical machine, and it may be in operation with low-speed, high-torque and direct-driven. In this paper, three types of MGPM machines are present, and a quantitative comparison among them is performed by finite element analysis (FEA). The magnetic field distribution, stable torque and back EMF are obtained at no-load. The results show that three types of MGPM machine are suitable for different application fields respectively according to their own advantages, such as high torque and back EMF, which form an important foundation for MGPM electrical machine research.

Computation of Torque of an Electrical Machine With Different Types of Finite Element Mesh in the Air Gap

In the numerical analysis of electrical machines, accurate computation of the electromagnetic torque is desired. Maxwell stress tensor method and Coulomb's method are the most commonly used methods for computing torque numerically. However, several other methods have also been developed and are being used. These methods are observed to have several accuracy issues related to the finite element discretization used in the air gap of the machine. In this paper, the effect of various finite element meshes in the air gap of the machine and the effect of the shape of the elements used to compute the torque are studied and discussed. This paper carefully compares the torques obtained from a direct method and a method based on the power balance of the machine.

Analysis of Linear Flux-Switching Permanent Magnet Motor Using Response Surface Methodology

This paper focuses on the performance analysis of linear flux-switching permanent magnet (LFSPM) motor. The analysis of electrical machines is mostly done by finite element method (FEM) and analytical method. However, it is time-consuming to determine the effects of the design parameters on the motor performance with FEM. It is also difficult to utilize the analytical technique for the intricate structure of LFSPM motor. In this paper, the response surface methodology in conjunction with FEM is proposed to analyze the LFSPM motor efficiently. As a demonstration, the influence of design parameters on the motor net thrust force is analyzed with the proposed method. Analysis of variance and comparison between the fitted response and results obtained from FEM all confirm the validity of the proposed method.

Analytical Modeling and Analysis of Axial-Flux Interior Permanent-Magnet Couplers

Analytical calculations are effective in preliminary design stages and analysis of electric machines. In this paper, for axial-flux interior permanent-magnet (PM) eddy-current couplers, an analytical model is developed, which is able to deal with the complex machine geometry and take into account material properties such as iron saturation and PM characteristics. The design considerations of the machine are also presented. Moreover, the studied structure shows several advantages in terms of mechanical and magnetic performances over the couplers with surface PMs. The three-dimensional (3-D) finite-element method is employed in the analyses and evaluations. Finally, an experimental prototype is built to validate the model.

Editorial on the Special Issue on Advanced Control of Electric Motor Drives

In APRIL 2013, a call was sent out to authors to propose papers for publication in the IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS (JESTPE) for a Special Issue on advanced control of electric motor drives. Seventy nine papers were received for review and 21 were accepted for publication. The accepted papers are broadly divided into four parts: 1) sensorless control of electric machines; 2) fault-resilient control strategies; 3) advanced motor control techniques; and 4) design and analysis of synchronous-type electric machines.

Electric Machine Analysis, Control and Verification for Mechatronics Motion Control Applications, Using New MATLAB Built-in Function and Simulink Model

This paper proposes a new, simple and user-friendly MATLAB built-in function, mathematical and Simulink models, to be used to early identify system level problems, to ensure that all design requirements are met, and, generally, to simplify Mechatronics motion control design process including; performance analysis and verification of a given electric DC machine, proper controller selection and verification for desired output speed or angle.

Finite-Element Analysis of Electrical Machines for Sensorless Drives With High-Frequency Signal Injection

A challenge during the design process of an electrical machine is the characterization of the various parameters in a computational time as short as possible. Frequently it is required the computation of the electrical machine parameters that are necessary for the tuning of the drive control algorithm. This paper deals with a strategy to compute the high-frequency signal injection response of a sensorless controlled electrical machine. It allows to determine the self-sensing capability of the machine directly during the design process. Such capability can be defined in any given operating point, for example, along the maximum-torque-per-amps trajectory. Then, also the high-frequency machine parameters can be computed. In addition, the strategy proposed here requires a very short computational time to get such data. After a magnetostatic field analysis, carried out so as to get the torque for a given current, the flux density distribution is stored, and the differential reluctivity tensor is evaluated in each element of the mesh. Then, a time-harmonic analysis is carried out in a linearized structure so as to compute the d - q parameters at the injection frequency. In order to validate the proposed procedure, experimental results on different machine type are included in this paper. This allows to prove the reliability of the procedure as a valued tool for the characterization of the machine.

Processing Stability Analysis of Wire Cut Electric Discharge Machine with High Speed

In this article, unstable factor analysis is done in Wire cut electric discharge machine with high speed (WEDM HS), which focus on effect of processing Stability from electrical processing parameters, machine parameters, electrode wire, cutting fluid and conductive block, and how to adjust and excluding factors in order to enhance WEDM processing stability ,ensure machine parts surface quality, dimensional accuracy and processing efficiency.

Intelligent MADS With Clustering and Elastic Net and Its Application to Optimal Design of Interior PM Synchronous Machines

Optimal design of the electric machines is interlinked with the optimization algorithm for obtaining the quantitative optimum and numerical analysis of electric machines for the objective function. The optimization algorithm is required to evaluate the objective function minimal times since numerical analysis of the electric machines consumes a lot of time. In this paper, intelligent MADS with a clustering and elastic net is newly adopted for the optimal design of electric machines to raise the reliability of the global optimization and fast convergence time. In particular, the proposed algorithm is employed to the optimal design of the interior permanent-magnet PM synchronous machine minimizing torque ripples, which has been regarded as one of the complicated design problems.

Non-Conforming Sliding Interfaces for Relative Motion in 3D Finite Element Analysis of Electrical Machines by Magnetic Scalar Potential Formulation Without Cuts

This paper discusses non-conforming sliding interfaces for motion in combination with a magnetic scalar potential formulation. Lagrange multiplier are used to implement the relative motion of stator and rotor. The utilization of the specific Lagrange multiplier approach implies the application of a magnetic scalar potential formulation in 3D Finite Element (FE) modeling of electrical machines because up to the present a canonical definition of biorthogonal basis functions for the magnetic vector potential is not available.

Extended Anisotropic Layer Theory for Electrical Machines

The Anisotropic Layer Theory (ALT) has been extensively used for electric machine analysis, due to its ability to take finite iron permeability into account globally. However, the effect of the slot openings, which are often present in slotted electrical machines, is neglected. In this work, an extension of the ALT to account for slot openings is proposed. The classical ALT is combined with the Harmonic Modeling Technique (HMT) for slotted structures by assuming infinitely permeable tooth tips. A semi-analytical solution is described for the classical and the extended ALT model. The results of the semi-analytical models are compared to Finite Element Analysis (FEA) results.

THE NUMERICAL FIELD ANALYSIS OF EXCITATION MODES AND OF THE DIFFERENT TYPES OF THE ARMATURE REACTION IN A POWERFUL TURBOGENERATOR

Principle and the numerical field analysis results of the different excitation modes and of the different types of the armature reaction of powerful turbogenerator are presented. A selection of the the magnetic field excitation factors in the idle mode, the rated load and short-circuit, as well as those specific modes that are characterized by longitudinal demagnetizing and magnetizing and more cross-reaction of the armature excitation of the magnetic field only the stator winding along the longitudinal and transverse axes of the rotor is shown. The principle, which allows by the results of the magnetic field calculation in each mode to determine the key electromagnetic values (magnetic flux and EMF) and the phase relationship between them and the currents is considered. The pictures of the magnetic fields are graphically presented in all modes, and the principle of the corresponding vector diagrams construction is also presented on the basis of calculation of these fields. In the original received vector diagrams it is possible to identify qualitatively and quantitatively the share and role of the magnetic field of the rotor and the stator magnetic field. The conducted research can be the basis for improving the system of study, analysis and design of turbogenerators and other electric machines because the considered method of analysis of magnetic fields is quite universal

Direct torque control of synchronous machines with different connections in feed system

In this article stability analysis of synchronous electrical machines with different connections in feed system is considered. Conditions of load change, under which the transient process is stable, are found. The automatic torque control is suggested for synchronous electrical machines. It allows to improve stability of these machines. The existence conditions of second-kind limit cycles are found. Also it is shown that these conditions are not fulfilled when the automatic control is sufficiently powerful. The numerical modeling is done.

전기강판의 벡터 자기특성을 고려한 전기기기의 손실특성 해석

This paper presents vector magnetic properties of an electrical steel sheet (ESS) employed for electric machine and iron loss analysis considering the vector magnetic properties of the ESS. The vector magnetic properties of the ESS are measured by using a two-dimensional single sheet tester and modeled by an E&S vector hysteresis model to be applied to finite element method. The finite element analysis considering the vector magnetic properties is applied to iron loss analysis of a three-phase induction motor model, and the influences of the vector magnetic properties on the iron loss distribution are verified by comparing with numerical results from a typical B-H curve model.

디지털 제어형 고주파 전력발생장치 개발에 관한 연구

The aim of this research is to develop more actual high-frequency power generators that includes various noise, to make flexible control systems for test or performance analysis of electric and electronic machines. It proposed power generating circuits using basic amplifier, B-level Push-Pull type, and FPGA for the easier control to get data and transmit. And it also testify to realize the proposed systems to report output data by input waveform and designed the digital LPF with MATLAB, universal simulation tools, for this study.

Air-Gap Convection in Rotating Electrical Machines

This paper reviews the convective heat transfer within the air gap of both cylindrical and disk geometry rotating electrical machines, including worked examples relevant to fractional horsepower electrical machines. Thermal analysis of electrical machines is important because torque density is limited by maximum temperature. Knowledge of surface convective heat transfer coefficients is necessary for accurate thermal modeling, for example, using lumped parameter models. There exists a wide body of relevant literature, but much of it has traditionally been in other application areas, dominated by mechanical engineers, such as gas turbine design. Particular attention is therefore given to the explanation of the relevant nondimensional parameters and to the presentation of measured convective heat transfer correlations for a wide variety of situations from laminar to turbulent flow at small and large gap sizes for both radial-flux and axial-flux electrical machines.

A Novel Approach to Saturation Characteristics Modeling and Its Impact on Synchronous Machine Transient Stability Analysis

Saturation in the ferromagnetic core significantly affects the performance of electrical machines. In the performance analysis of electrical machines, an accurate representation of the saturation characteristics in the machine model is important. In this paper, a new trigonometric algorithm is proposed to represent the saturation characteristics of electrical machines based on the measured saturation characteristics data points. This model can be applied to various kinds and sizes of electrical machines. The calculated results demonstrate the effectiveness of the proposed model. This trigonometric model has been applied to a conventional synchronous machine model and extensive stability performance analysis has been carried out. This further reveals the usefulness of the proposed trigonometric saturation model and the importance of the inclusion of saturation in stability analysis.

Preliminary induction motor electromagnetic sizing based on a geometrical approach

A methodology to design three-phase squirrel-cage induction motors is presented. The main aim of the study is the preliminary electromagnetic sizing of the machine, obtaining the machine overall dimensions (diameters, core axial length and rough stator and rotor shape) and a draft of the stator winding specifications (turn number and wire area). The procedure is based on a simple geometrical approach and self-consistent equations, without any use of empirical/corrective coefficients. In the proposed design tool, the machine geometrical dimensions are automatically computed starting from a few design specifications imposed by the user, such as rated voltage and torque and electric and magnetic material solicitations. In this study, the design procedures and algorithms are described step-by-step and, for each step, the used equations are reported in detail, in order to allow readers to develop own `do-it-yourself` software for induction motor electromagnetic design. The authors developed this software in a Microsoft Excel electronic sheet using embedded Visual Basic for Applications. To prove the goodness and accuracy of the proposed design tool, a comparison with two commercial software for electrical machine design and analysis has been done and discussed.