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Disturbing vibrations and noise of electrical machines are gaining impact. The paper aims to focus on the necessity of estimating the electromagnetic, structure‐dynamical, and acoustic behaviour of the machine during designing and before proto‐typing.

An adequate tool is numerical simulation applying the finite‐element method (FEM) and the boundary‐element method (BEM) allowing for the structured analysis and evaluation of audible noise also caused by manufacturing tolerances.

The simulated results show good accordance to measurement results. The methods and simulation tools allow the analysis and evaluation of every type of energy converter with respect to its electromagnetic, structure‐dynamical and acoustic behaviour.

The methods developed and proved can be applied to any electromagnetic device in general.

To present results of research closely linked with real life applications. It resumes work of a period of about two years.

Applying the finite‐element method (FEM) the impact of balancing kerfs in the bars of squirrel‐cage rotors of a small scale, mass series induction machine (IM) is studied. For the analysis and design optimization of the IM both, 2D electromagnetic, multi‐slice and 3D structure‐dynamic models are considered. Introducing and applying a novel 2D‐3D force‐transformation scheme, all possible balancing variants of the IM are studied in terms of electromagnetic and mechanical behaviour.

The obtained results lead to a significant improvement of the studied IM. In fact, it is found, that the method of balancing the rotor by carving the rotor bars results in higher unbalanced pull rather than reducing it. This is due to electromagnetic unbalance caused by balancing. Hence, the IM is no longer balanced in series production. This again leads to a major economic benefit.

Using the FEM for simulation of structure dynamic problems is often limited to how the boundary layers are handled. In real life materials are not “connected” but glued or clamped. Therefore, the behaviour can only be adopted by manipulating the material parameters derived from iterative parameter adoption by measurement.

Owing to the findings the IM is no longer balanced in series production, leading to a significant reduction of costs. In general, the applied methods can be used for the analysis and optimization of any kind of manufacturing or tolerance problem of electrical machines such as various kinds of eccentricity, punching kerfs, broken bars, magnetization errors in permanent‐magnet machines, etc.

This contribution gives a close insight of how to study the impact of manufacturing and tolerance problems of electric machinery, applying the method to an IM with balancing kerfs.

To present results of research closely linked to real life applications and to resume the work of a period of a few years.

The combination of finite‐element method (FEM) and boundary‐element method is applied to simulate the electromagnetic, mechanical, and acoustic behaviour of an induction machine with squirrel‐cage rotor. The paper gives an overall view of the workflow and the implemented mathematics, starting off with the two‐dimensional, transient electromagnetic simulation and the succeeding three‐dimensional, static electromagnetic simulation. Theory and results of the mechanical and acoustic simulations are discussed.

A main result of the research work is that the simulation of the acoustic behaviour of an electrical machine is very time‐consuming. Furthermore, geometry adoption, especially of the mechanical model, is very sensible.

Using the FEM for simulation of structure dynamic problems is often limited to how the boundary layers are handled. In real life materials are not “connected” but glued or clamped. Therefore, the behaviour can only be adapted by manipulating the material parameters. There are other methods known for simulation, which could be applied. On the other hand, measurements could be used for iterative parameter adoption.

A significant result of the work is that the results obtained only allow for comparison. Exactness is more a question of modelling the real behaviour than matching the results to measurement in terms of values.

This paper gives an overview of how to simulate the complete chain from electromagnetics to acoustics of an electric machine.

The purpose of this paper is to consider thermal analysis as part of an automated sizing and design process. The temperature estimation at characteristic points of the machine, and in particular in permanent magnets, is essential to accurately simulate the electromagnetic behavior and avoid irreversible demagnetization.

In this paper, an electromagnetic dimensioning model, parameterized by finite element analysis, is coupled to a thermal lumped‐parameter model to constitute a fast and efficient design tool for electrical machines.

A parameterized and hybrid FE‐analytical electromagnetic model, which combines analytical and numerical advantages, to archive a fast and accurate electromagnetic simulation results is combined with a thermal lumped‐parameter model for water‐cooled and passive air‐cooled surface mounted permanent magnet synchronous machines (PMSM).

Sizing, electromagnetic and thermal modeling aspects are integrated into an automated design process. The whole design process is demonstrated on two standard industrial servo motors for passive and active water cooling and afterwards compared with available measurements.

The proposed method allows considering thermal aspects during the iterative automated electromagnetic design process of PMSM.

The paper aims to provide an approach to actively decrease the radiation of acoustic noise in synchronous machines.

Splitting regular three‐phase windings of synchronous machines into two independent three‐phase systems allows for an active influence of the current waveform if both winding systems are mutually displaced against each other. The harmonics content of each phase‐current varies due to the mutual inductive coupling with participating currents of both systems. Therefore, the ensuing force‐density distribution on the stator teeth varies accordingly. Resulting structure dynamics and furthermore the radiation of relevant harmonics of the acoustic noise are based on the mechanical excitation of considered force‐density distributions.

Configurations of mutual displacement of phase windings of both winding systems with significant decrease of mechanical deformation and emitted acoustic noise are found. Simulation methods to entirely describe and prove the behavior described are developed.

The proposed approach is developed for a particular synchronous machine. Other machine types are conceivable for analysis in the same manner. Tools need to be adapted. Universal and reliable statements regarding acoustic behavior depend on the mechanical restraint of the machine and may therefore vary.

Active force‐density distribution is used for the noise reduction of alternators in vehicle applications. Additionally, wind‐power generators are considered for the application of split stator winding systems to actively counteract inhomogeneous force distributions on the rotor, evoked by stalling of the propeller blades during pole passing.

Active force‐density modification by stator winding modifications allows for the decrease of noise radiation of electrical machines with rotating‐field windings. Innovative simulation methods developed may now replace prototyping partially.

Finite‐element simulations of induction machines with squirrel‐cage rotor require transient solution algorithms. For this reason a transient 2D solver is utilized which takes rotational movement of the rotor into account. Its formulation and the time‐step algorithm are given. Two different kinds of eccentricity of the rotor and their combination are defined and studied. The three motor variants are computed and the torque, the net force, and the surface‐force density are compared in time and frequency domain.

To present a new approach for improvement and optimization of synchronous claw‐pole alternators without changing the general machine design.

Various changes on the magnetically relevant parts of the machine design have been discussed formerly to achieve improved electromagnetic and acoustic behavior. The electrical part of the machine is considered in this paper, varying the stator winding arrangement to achieve optimized behavior.

Provides information about motivation and the methodology of the optimization process. Presents the entire analysis, covering idea, technical and computational implementation as well as verification.

It describes a method based on the utilization of specific, partly self‐generated software, which perhaps limits its usefulness if mentioned tools are unavailable. However, the presented basic method is to be used generally.

This paper presents a promising approach to further optimize the design of synchronous claw‐pole alternators without major changes in the machine design.

The purpose of this paper is to develop an effective, yet simple analytical framework for optimization of permanent-magnet synchronous machines. Also, single/multi-objective optimizations are performed for a case-study machine with surface-mounted permanent magnets.

First, an accurate magnetic equivalent circuit is developed which takes all the material such as iron saturation and PM parameters into account. Then, through a Fourier analysis, it is combined with the d-q model of PM synchronous machines to achieve an optimization framework including the developed torque, back-EMF and a number of design considerations. Finally, a genetic algorithm (GA) is employed in the single/multi-objective design optimizations, which offers several design characteristics upon different desired outcomes.

An analytical design framework for the optimization of permanent-magnet synchronous machines is developed in this paper that can effectively account for all material properties such as iron saturation and PM characteristics, and take into account the design considerations, all of which are shown as superiorities of the proposed approach over the existing method. In addition, the proposed framework is relatively simpler in terms of implementing. The model is verified by employing finite element method. Moreover, sensitivity analysis is carried out to investigate the influence of the design parameters on the machine performance, which provides valuable information for the designer of such devices. Finally, a GA is utilized to perform single/multi-objective optimization schemes whose objectives are minimizing the torque ripples, back-EMF total harmonic distortion and PM volume.

The proposed framework is new approach that could be employed in the design optimization of PM synchronous machines. Contrary to existing method, it is simpler and more effective in taking the material properties such as iron saturation and PM characteristics into account.

The purpose of this paper is to present a method for analyzing higher magnetic force harmonics in electrical machines based on electromagnetic finite element simulation.

Sampling of air gap field solution data allows for a Fourier decomposition of magnetic forces and flux densities. A two‐dimensional convolution gives insight into the spectral decomposition of forces responsible for acoustic noise, vibration and higher torque harmonics.

The proposed approach seems especially suitable for synchronous machine models. The influence of magnetic circuit design parameters that are difficult to calculate analytically on the harmonic air gap content can be analyzed and the spectral force decomposition illustrated by means of space vectors.

The approach is generalized to the convolution and analysis of arbitrarily sampled two‐dimensional data in this paper.

The S-MCSRM is a two-phase excited switched reluctance motor (SRM), with the short flux path and mutual inductance coupling, which is suitable for the oil submersible pump application owing to large torque and three-wire connection with the standard full-bridge power converter. However, there is not literature to disclose its model due to the complicated mutual inductance coupling. The FEM model is a time-consuming method to analyze this motor. For the first time, this paper aims to propose an S-MCSRM model for performance analysis and control method developing. The proposed model would save simulation time and be a theoretical fundamental for further implementing control algorithm.

The S-MCSRM's operating principle is analyzed, and the voltage equation and the generated torque are deduced. The FEM is utilized to obtain the five typical magnetization curves that describe the S-MCSRM's magnetic path characteristic. The magnetic co-energy equation, phase torque and total torque equations are obtained. From the basic voltage equation, the S-MCSRM's state space model is built for the dynamic analysis and control purpose. The S-MCSRM is widely analyzed in detail by using the proposed model and comparison with the conventional SRM. JMAG finite element package is used to verify the proposed model.

The proposed modeling method is validated by the identical results to those from FEM-based JMAG software. The proposed model just takes second-level time, which is far less than minute-level time consuming of FEM method. The S-MCSRM generates larger torque than the conventional SRM, with three-wire and standard full bridge power converter, and it is confirmed that the S-MCSRM is suitable for the oil submersible pump applications.

This paper proposes a new modeling method for the S-MCSRM to exactly analyze the motor's operating performances, and also it is a theoretical fundamental for developing control algorithm. The proposed model saves much time in analysis, calculation, and simulation, when compared to the FEM method. The completed analysis including flux linkages, torque, torque-ripple, and torque-speed characteristic discloses the S-MCSRM's steady-state operating performances, which provides the deep insight for this kind of motor's applications.