The prediction of iron losses under PWM excitation using the classical Preisach model

2016 ◽  
Vol 35 (6) ◽  
pp. 1996-2006 ◽  
Author(s):  
Sajid Hussain ◽  
David Lowther
Keyword(s):  
Harmonic Component ◽  
Total Iron ◽  
Iron Loss ◽  
Magnetic Flux Density ◽  
Preisach Model ◽  
Content Type ◽  
Iron Losses ◽  
Novel Approach ◽  
Harmonic Components ◽  
Dynamic Inverse

Purpose The losses incurred in ferromagnetic materials under PWM excitations must be predicted accurately to optimize the design of modern electrical machines. The purpose of this paper is to employ mathematical hysteresis models (i.e. classical Preisach model) to predict iron losses in electrical steels under PWM excitation without compromising the computational complexity of the model. Design/methodology/approach In this paper, a novel approach based on the dynamic inverse Preisach model is proposed to model the iron losses. The PWM magnetic flux density waveform is decomposed into its harmonic component using Fourier series and a weighted Everett function is computed based on these harmonic components. The Preisach model is applied for the given flux waveform and results are validated against the measurements. Findings The paper predicts the total iron loss by computing a weighted Everett function based on the harmonics present in PWM waveform. Moreover, it formulates the possibility of utilizing the classical Preisach model to predict iron losses under PWM excitation. Research limitations/implications The approach is still limited in terms of its application at high frequencies. This work may eventually lead toward the accurate prediction of iron loss under PWM excitation in electromagnetic machine design. Practical implications The paper provides a simple approach applying the Preisach model for the prediction of iron losses under PWM excitation. The proposed approach does not require additional experimental data beyond B-H loops measured under sinusoidal excitation. Originality/value A novel approach is presented to incorporate the frequency dependence into a static inverse Preisach model. The approach extends the ability of the static Preisach model to compute total iron loss under PWM excitation using a weighted Everett function.

Simulation of iron losses in induction machines using an iron loss model for rotating magnetization loci in no electrical steel

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Martin Marco Nell ◽  
Benedikt Schauerte ◽  
Tim Brimmers ◽  
Kay Hameyer
Keyword(s):  
Finite Element ◽  
Flux Density ◽  
Core Loss ◽  
Induction Machine ◽  
Iron Loss ◽  
Magnetic Flux Density ◽  
Loss Model ◽  
Content Type ◽  
Iron Losses ◽  
Loss Models

Purpose Various iron loss models can be used for the simulation of electrical machines. In particular, the effect of rotating magnetic flux density at certain geometric locations in a machine is often neglected by conventional iron loss models. The purpose of this paper is to compare the adapted IEM loss model for rotational magnetization that is developed within the context of this work with other existing models in the framework of a finite element simulation of an exemplary induction machine. Design/methodology/approach In this paper, an adapted IEM loss model for rotational magnetization, developed within the context of the paper, is implemented in a finite element method simulation and used to calculate the iron losses of an exemplary induction machine. The resulting iron losses are compared with the iron losses simulated using three other already existing iron loss models that do not consider the effects of rotational flux densities. The used iron loss models are the modified Bertotti model, the IEM-5 parameter model and a dynamic core loss model. For the analysis, different operating points and different locations within the machine are examined, leading to the analysis of different shapes and amplitudes of the flux density curves. Findings The modified Bertotti model, the IEM-5 parameter model and the dynamic core loss model underestimate the hysteresis and excess losses in locations of rotational magnetizations and low-flux densities, while they overestimate the losses for rotational magnetization and high-flux densities. The error is reduced by the adapted IEM loss model for rotational magnetization. Furthermore, it is shown that the dynamic core loss model results in significant higher hysteresis losses for magnetizations with a high amount of harmonics. Originality/value The simulation results show that the adapted IEM loss model for rotational magnetization provides very similar results to existing iron loss models in the case of unidirectional magnetization. Furthermore, it is able to reproduce the effects of rotational flux densities on iron losses within a machine simulation.

Adaptation and parametrization of an iron loss model for rotating magnetization loci in NO electrical steel

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Benedikt Schauerte ◽  
Martin Marco Nell ◽  
Tim Brimmers ◽  
Nora Leuning ◽  
Kay Hameyer
Keyword(s):  
Magnetic Flux ◽  
Flux Density ◽  
Electrical Steel ◽  
Electrical Machines ◽  
Iron Loss ◽  
Magnetic Flux Density ◽  
Loss Model ◽  
Content Type ◽  
One Dimensional ◽  
Iron Losses

Purpose The magnetic characterization of electrical steel is typically examined by measurements under the condition of unidirectional sinusoidal flux density at different magnetization frequencies. A variety of iron loss models were developed and parametrized for these standardized unidirectional iron loss measurements. In the magnetic cross section of rotating electrical machines, the spatial magnetic flux density loci and with them the resulting iron losses vary significantly from these unidirectional cases. For a better recreation of the measured behavior extended iron loss models that consider the effects of rotational magnetization have to be developed and compared to the measured material behavior. The aim of this study is the adaptation, parametrization and validation of an iron loss model considering the spatial flux density loci is presented and validated with measurements of circular and elliptical magnetizations. Design/methodology/approach The proposed iron loss model allows the calculation and separation of the different iron loss components based on the measured iron loss for different spatial magnetization loci. The separation is performed in analogy to the conventional iron loss calculation approach designed for the recreation of the iron losses measured under unidirectional, one-dimensional measurements. The phenomenological behavior for rotating magnetization loci is considered by the formulation of the different iron loss components as a function of the maximum magnetic flux density Bm, axis ratio fAx, angle to the rolling direction (RD) θ and magnetization frequency f. Findings The proposed formulation for the calculation of rotating iron loss is able to recreate the complicated interdependencies between the different iron loss components and the respective spatial magnetic flux loci. The model can be easily implemented in the finite element analysis of rotating electrical machines, leading to good agreement between the theoretically expected behavior and the actual output of the iron loss calculation at different geometric locations in the magnetic cross section of rotating electrical machines. Originality/value Based on conventional one-dimensional iron loss separation approaches and previously performed extensions for rotational magnetization, the terms for the consideration of vectorial unidirectional, elliptical and circular flux density loci are adjusted and compared to the performed rotational measurement. The presented approach for the mathematical formulation of the iron loss model also allows the parametrization of the different iron loss components by unidirectional measurements performed in different directions to the RD on conventional one-dimensional measurement topologies such as the Epstein frames and single sheet testers.

Iron loss simulation using a local material model

2019 ◽  
Vol 38 (4) ◽  
pp. 1224-1234
Author(s):  
Benedikt Groschup ◽  
Silas Elfgen ◽  
Kay Hameyer
Keyword(s):  
A Priori ◽  
Material Model ◽  
Edge Length ◽  
Iron Loss ◽  
Local Magnetization ◽  
Content Type ◽  
Local Loss ◽  
Cut Edge ◽  
Iron Losses ◽  
Local Material

Purpose The cutting process of the electric machine laminations causes residual mechanical stress in the soft magnetic material. A local magnetic deterioration can be observed and the resulting local and global iron losses increase. A continuous local material model for the consideration of the changing magnetization properties has been introduced in a previous work as well as an a priori assessment of iron losses. A local iron loss calculation considering both a local magnetization and local loss parameters misses yet. The purpose of this study is to introduce a local iron loss calculation model considering both a local magnetization and local loss parameters. Design/methodology/approach In this paper, an approach for local iron loss simulation is developed and a comparison to the cut-edge length-dependent loss model is given. The comparison includes local loss distribution in the lamination as well as the impact on the overall motor efficiency and vehicle range in an electric vehicle driving cycle. Findings For an analysis of the resulting local iron loss components, both the local magnetization and iron loss parameters must be considered using physically based models. Consistently, a local iron loss model is presented in the work. The developed model can be used to gain detailed information of the local loss distribution inside the machine. The comparability of this local iron loss with the cut-edge length approach for overall system characteristics, e.g. efficiency or driving range, is shown. Originality/value A local iron loss simulation approach is a physical accurate model to describe the influence of cutting techniques on electric machine characteristics. A comparison with the less complicated a priori assessment gives detailed information about the necessity of the local model under consideration of the given problem.

scholarly journals Mitigation Method of Slot Harmonic Cogging Torque Considering Unevenly Magnetized Permanent Magnets in PMSM

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3887
Author(s):  
Jeong ◽  
Lee ◽  
Hur
Keyword(s):  
Permanent Magnet ◽  
Permanent Magnets ◽  
Permanent Magnet Synchronous Motor ◽  
Harmonic Component ◽  
Magnetic Flux Density ◽  
Element Analysis ◽  
Cogging Torque ◽  
Maxwell Stress Tensor ◽  
The Finite Element Analysis ◽  
Harmonic Components

This paper presents a mitigation method of slot harmonic cogging torque considering unevenly magnetized magnets in a permanent magnet synchronous motor. In previous studies, it has been confirmed that non-uniformly magnetized permanent magnets cause an unexpected increase of cogging torque because of additional slot harmonic components. However, these studies did not offer a countermeasure against it. First, in this study, the relationship between the residual magnetic flux density of the permanent magnet and the cogging torque is derived from the basic form of the Maxwell stress tensor equation. Second, the principle of the slot harmonic cogging torque generation is explained qualitatively, and the mitigation method of the slot harmonic component is proposed. Finally, the proposed method is verified with the finite element analysis and experimental results.

scholarly journals Analysis and identification of influential phenomena on iron losses in embedded permanent magnet synchronous machine

2017 ◽  
Vol 68 (1) ◽  
Author(s):  
Mitja Breznik ◽  
Viktor Goričan ◽  
Anton Hamler ◽  
Selma Čorović ◽  
Damijan Miljavec
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Magnetic Flux ◽  
Permanent Magnet ◽  
Flux Density ◽  
Iron Loss ◽  
Magnetic Flux Density ◽  
Iron Losses ◽  
Ipm Machine ◽  
Element Method

AbstractThis paper presents magnetic flux density behaviour in laminated electrical sheets which affects the results and precision of iron losses calculation in imbedded permanent magnet (IPM) machine. Objective of the research was to analyse all the influential phenomena that were identified through iron loss models analysis, finite element method simulations and iron loss measurements. The presence of phenomena such as harmonic content and rotational magnetic fields are confirmed with finite element method analysis of concentrated and distributed winding IPM machine. A significant magnetic flux density ripple in the rotor of concentrated winding IPM machine in comparison to distributed winding IPM machine is revealed and analysed. Behaviour that affects iron loss in the rotor of synchronous machines in the absence of first order harmonic is analysed. The DC level added to alternating magnetic flux density was used in experiment to mimic magnetic behaviour on the rotor of IPM machine and further to calculate iron losses.

Simplified analysis of iron loss in three-phase transformer considering rotating loss

2013 ◽  
Vol 33 (1/2) ◽  
pp. 74-84
Author(s):  
Yang Liu ◽  
Yanli Zhang ◽  
Dexin Xie ◽  
Baodong Bai
Keyword(s):  
Design Methodology ◽  
Silicon Steel ◽  
Iron Loss ◽  
Magnetic Flux Density ◽  
Element Analysis ◽  
Content Type ◽  
Three Phase ◽  
The Finite Element Analysis ◽  
Simplified Method ◽  
Property Measurement

Purpose – A simplified method for calculating iron loss of three-phase transformer is proposed in this paper. The rotating iron loss measured from 2-D vector magnetic property measurement system of gain-oriented silicon steel sheet can be taken into account in this method. The paper aims to discuss these issues. Design/methodology/approach – The finite element analysis formulation is combined with the magnetic reluctivity model expressed by diagonal tensor for 2-D nonlinear and anisotropic magnetic problem, while the iron loss is computed in terms of the interpolation of rotational loss curves measured under various loci of controlled magnetic flux density B. Findings – The iron loss of three-phase transformer is obtained by the proposed method. And the calculating iron loss is verified with experimental results. Originality/value – The method presented in this paper enables the iron loss of three-phase transformer to be more accurately calculated and more easily applied, considering the rotational iron loss.

Iron loss in FSPMM: 2D FEA-based comparative study between single and double-layer topologies

2015 ◽  
Vol 34 (1) ◽  
pp. 61-75 ◽  
Author(s):  
Asma Masmoudi ◽  
Ahmed Masmoudi
Keyword(s):  
Double Layer ◽  
Eddy Current ◽  
Permanent Magnets ◽  
Single Layer ◽  
Iron Loss ◽  
Permanent Magnet Machines ◽  
Content Type ◽  
Constant Torque ◽  
Harmonic Content ◽  
Iron Losses

Purpose – The purpose of this paper is to compare the study between two topologies of fractional-slot permanent-magnet machines such that: double-layer topology and single-layer one. The comparison considers the assessment of the iron loss in the laminated cores of the magnetic circuit as well as in the permanent magnets (PMs) for constant torque and flux weakening ranges. Design/methodology/approach – The investigation of the hysteresis and eddy-current loss has been carried out using 2D transient FEA models. Findings – It has been found that the stator iron losses are almost the same for both topologies. Whereas, the single-layer topology is penalized by higher iron loss especially the eddy-current ones taking place in the PMs. This is due to their denser harmonic content of the armature air gap MMF spatial repartition. Originality/value – The analysis of the iron loss maps in different parts of each machine including stator and rotor laminations as well as the PMs, in one hand, and the investigation of their variation with respect to the speed, in the other hand, represent the major contribution of this work.

Calculation and validation of iron loss in laminated core of power and distribution transformers

2013 ◽  
Vol 33 (1/2) ◽  
pp. 137-146 ◽  
Author(s):  
Xiaoyan Wang ◽  
Zhiguang Cheng ◽  
Li Lin ◽  
Jianmin Wang
Keyword(s):  
Magnetic Flux ◽  
Flux Density ◽  
Core Loss ◽  
Iron Loss ◽  
Magnetic Flux Density ◽  
Content Type ◽  
The Core ◽  
Distribution Transformers ◽  
The Impact ◽  
Transformer Core

Purpose – The purpose of this paper is to present a simple method to analyze the iron loss in the laminated core of power and distribution transformers. Design/methodology/approach – This paper presents a practical method to calculate the no-load loss in the transformer cores. Considering the non-uniformity of the magnetic flux density in the corner areas of the Epstein frames will affect the measurement precision of the Wt-B curves then further affect the core loss calculation in FEM, a dual-Epstein frame method is used to measure the Wt-B curves with the Epstein sample stripes cutting by different angles to the rolling direction. A 2D FEM that considers the type of joints of the core and eddy current effect in the laminations is used to analyze the core loss with multi-angle Wt-B curves. Findings – The impact of lamination thickness, size of gaps and type of joint of the core are considered. Considering the no-load testing conditions, harmonics in the exciting currents are taken into account. Originality/value – Harmonic wave of magnetic flux density in the transformer core is calculated and the core loss in the joint region is calculated by the loss curve measured with dual-Epstein frame. It makes the calculation result of transformer core loss more exactly.

Improved estimation of iron losses for non-sinusoidal voltages

2018 ◽  
Vol 37 (5) ◽  
pp. 1698-1706 ◽  
Author(s):  
Valentin Ionita ◽  
Lucian Petrescu ◽  
Emil Cazacu
Keyword(s):  
Experimental Data ◽  
Magnetic Induction ◽  
Time Integration ◽  
Prediction Method ◽  
Power Grids ◽  
Preisach Model ◽  
Content Type ◽  
Electrical Grid ◽  
Excess Loss ◽  
Iron Losses

Purpose The electrical machines connected to modern electric power grids are non-sinusoidal excited, and their augmented losses, including iron losses, limit their working characteristics. This paper aims to propose a prediction method for iron losses in non-oriented grains (NO) FeSi sheets under non-sinusoidal voltage, involving an inverse classical Preisach hysteresis model and the time-integration of each loss component. Design/methodology/approach The magnetic history management in inverse Preisach model is optimized and a numerical Everett function is identified from measured symmetrical hysteresis cycles. The experimental data for sinusoidal waveforms obtained by a single sheet tester were also used to identify the parameters involved in Bertotti’ losses separation method. The non-sinusoidal magnetic induction waveform, corresponding to a measured voltage in an industrial electrical grid, was the input for Preisach model, the output magnetic field being accurately computed. The hysteresis, classical and excess losses are calculated by time-integration and the total losses are compared with those obtained for sinusoidal excitation. Findings The proposed method allows to estimate the iron losses for non-sinusoidal magnetic induction, using carefully identified parameters of FeSi NO sheets, using experimental data from sinusoidal regimes. Originality/value The method accuracy is assured by using a numerical Everett function, a variable Preisach grid step (adapted for the high non-linearity of FeSi sheets) and high-order fitting polynomials for the microscopic parameters involved in the excess loss estimation. The procedure allows a better design of magnetic cores and an improved estimation of the electric machine derating for non-sinusoidal voltages.

Effect of mechanical stress on different iron loss components up to high frequencies and magnetic flux densities

2017 ◽  
Vol 36 (3) ◽  
pp. 580-592 ◽  
Author(s):  
Jan Karthaus ◽  
Simon Steentjes ◽  
Nora Leuning ◽  
Kay Hameyer
Keyword(s):  
Mechanical Stress ◽  
Electrical Steel ◽  
Mechanical Stresses ◽  
Iron Loss ◽  
Content Type ◽  
High Frequencies ◽  
Steel Sheets ◽  
Iron Losses ◽  
Loss Component ◽  
Electrical Steel Sheets

Purpose The purpose of this paper is to study the variation of the specific iron loss components of electrical steel sheets when applying a tensile mechanical load below the yield strength of the material. The results provide an insight into the iron loss behaviour of the laminated core of electrical machines which are exposed to mechanical stresses of diverse origins. Design/methodology/approach The specific iron losses of electrical steel sheets are measured using a standardised single-sheet tester equipped with a hydraulic pressure cylinder which enables application of a force to the specimen under test. Based on the measured data and a semi-physical description of specific iron losses, the stress-dependency of the iron loss components can be studied. Findings The results show a dependency of iron loss components on the applied mechanical stress. Especially for the non-linear loss component and high frequencies, a large variation is observed, while the excess loss component is not as sensitive to high mechanical stresses. Besides, it is shown that the stress-dependent iron loss prediction approximates the measured specific iron losses in an adequate way. Originality/value New applications such as high-speed traction drives in electric vehicles require a suitable design of the electrical machine. These applications require particular attention to the interaction between mechanical influences and magnetic behaviour of the machine. In this regard, knowledge about the relation between mechanical stress and magnetic properties of soft magnetic material is essential for an exact estimation of the machine’s behaviour.

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