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This paper deals with coupled electromagnetic, hydrodynamic and mechanical motion phenomena in magnetorheological fluid brakes. The governing equations of these phenomena are presented. The numerical implementation of the mathematical model is based on the finite element method and a step‐by‐step algorithm. A computer program based on this algorithm was used to simulate the transients in a prototype of magnetorheological brake. The results of the calculations and measurements are presented.

This paper aims to elaborate the method and algorithm for the analysis of the influence of high temperature on electric and thermal properties of the materials, as well as thermal phenomena process.

The paper presents specially author’s software for the transient finite element analysis of coupled electromagnetic-thermal problems in a squirrel cage induction motor. The numerical implementation is based on finite element method and step-by-step algorithm. The nonlinearity of a magnetic circuit, the dependence of electric and thermal parameters on temperature, the movement of a rotor and skewed rotor bars have been taken into account. To verify the developed algorithm and software, the influence of high ambient temperature on selected electromagnetic and thermal parameters of the induction motor was examined.

The results of simulations compared with measurements confirm the adequacy of this approach to the analysis of coupled electromagnetic-thermal problems.

3D effects have only been taken into account when using quasi-3D techniques (e.g. the multi-slice for skewed rotor slots).

The author’s software developed can be useful in the analysis and design of squirrel cage motors, especially motors working in high ambient temperature.

The paper offers appropriate author’s software for the transient and steady-state analysis of coupled electromagnetic and thermal problems in squirrel cage motors with skewed slots.

Deals with coupled electromagnetic, hydrodynamic, thermodynamic and mechanical motion phenomena in magnetorheological fluid brake. Presents the governing equations of these phenomena. The numerical implementation of the mathematical model is based on the finite element method and a step‐by‐step algorithm. In order to include non‐linearity, the Newton‐Raphson process has been adopted. The method has been successfully adapted to the analysis of the coupled phenomena in the magnetorheological fluid brake. Present the results of the analysis and measurements.

The time‐stepping finite method of transient analysis in permanent magnet synchronous machines has been presented. This method has been used for determining the steady‐state and dynamic performance of the permanent magnet self‐starting synchronous motor. The movement of the rotor, the saturation of the ferromagnetic core, the properties of permanent magnet and eddy currents in the solid bars of the cage winding have been taken into account.

This paper deals with coupled electromagnetic, hydrodynamic and mechanical motion phenomena in magnetorheological fluid devices. The governing equations of these phenomena are presented. The numerical implementation of the mathematical model is based on the finite element method and a step‐by‐step algorithm. In order to include non‐linearity, the Newton‐Raphson process has been adopted. A prototype of an electromagnetic brake has been built at the Poznań University of Technology. The method has been successfully adapted to the analysis of this brake. The results of the analysis are presented.

System contains units which are the tools for the actuators designs, optimization and steady‐states or transients simulation. Design and optimization process has been based on the equivalent circuit model with “field” procedures for concentrated circuit parameters calculation. For the optimization the penalty function method combined with the conjugate gradients method has been adopted. In the steady‐states simulation, the entirely 2D or 3D field formulation has been employed. Whereas in transients, it is assumed that the field is produced under the time‐varying voltage constraints, so the combined field‐circuit formulation has been applied.

Paper presents an effective iterative method for 3D magnetic field calculation taking the nonlinearity and anisotropy of the material into account. Algorithm for simulation of coupled 3D field‐circuit transient problems has been also elaborated. Some steady‐state and transient characteristics of the E‐core electromagnet and shell‐type transformer have been calculated.

The purpose of this paper is to elaborate upon the mathematical model of coupled electromagnetic, fluid dynamic and motion phenomena that will allow for investigation of the magnetic hysteresis influence on the axial symmetry magnetorheological fluid (MRF) clutch operation.

To solve the partial differential equations describing magnetic vector and fluid velocity potential distributions in axial symmetry MRF electromechanical transducers the finite‐element methods have been applied. To solve model equations in the time domain, the time stepping method have been adopted. To introduce magnetic hysteresis phenomenon to presented approach the Jiles‐Atherton model have been applied. The physical properties of MRFs have been modeled by means of the Bingham model. Owing to high nonlinearity of the considered problem to solve obtained matrix equations systems the iterative Newton‐Raphson combined with the block over relaxation method have been applied.

The proposed model of coupled phenomena and the elaborated algorithm for solving the nonlinear model equations can be successfully applied in the analysis of transients in the MRF transducers taking fluid dynamics and magnetic hysteresis into account. Comparison of the measured and calculated clutch characteristics proves the model accuracy. Moreover, it has been shown that the residual magnetic flux density of the ferromagnetic core has significant impact on both to yield stresses forming in MRFs as well as the torque in disengagement clutch operation.

Development of the method for analysis of transients electromagnetic and fluid flow phenomena in MRF transducers taking magnetic hysteresis, electric circuits and motion into account. The presented approach is universal and can be successfully applied in other types of MRF electromechanical transducers such as clutch, brakes, rotary and linear dampers.

This paper aims to elaborate the method and algorithm for the analysis of the influence of temperature on back electromotive force (BEMF) waveforms in a line start permanent magnet synchronous motor (LSPMSM).

The paper presents a finite element analysis of temperature influence on BEMF and back electromotive coefficient in a LSPMSM. In this paper, a two-dimensional field model of coupled electromagnetic and thermal phenomena in the LSPMSM was presented. The influence of temperature on magnetic properties of the permanent magnets as well as on electric and thermal properties of the materials has been taken into account. Simulation results have been compared to measurements. The selected results have been presented and discussed.

The simulations results are compared with measurements to confirm the adequacy of this approach to the analysis of coupled electromagnetic-thermal problems.

The paper offers appropriate author’s software for the transient and steady-state analysis of coupled electromagnetic and thermal problems in LSPMS motor.

The paper presents a mathematical model for the hysteresis phenomenon in a multi-winding single-phase core type transformer. The set of loop differential equations was developed for Kth winding transformer model where the flux linkages of each winding includes a flux common Φ to all windings as function of magneto motive force Θ of all windings. The purpose of this paper is to first determine a hysteresis nonlinearity involved in Φ(Θ) function using modified Preisach theory and second to develop new analytical formula of Preisach distribution function (PDF).

It is assumed in this paper that flux linkage characteristics Ψ(i) of each winding have nonlinear component due to the magnetization characteristic of the steel core and sum of linear components due to the self and mutual leakage fluxes. This nonlinear component of Ψ(i) characteristic can be expressed as a flux common Φ to all windings vs ampere-turns Θ of all windings. The nonlinear flux linkage characteristics Ψ(i) of the tested transformer are calculated from the set of measured terminal voltages and terminal currents. To simulate magnetic behavior of the iron core the feedback scalar Preisach model of hysteresis is proposed which gives more accurate predictions than classical model. For this hysteresis model the PDF and feedback function are needed. The intend of this paper is to find these function as an analytical formulas which are convenient for numerical simulations. For identification of the PDF and feedback function parameters of the considered iron core of tested transformer the Levenberg-Marquardt optimization algorithm was used.

The flux common to all windings is calculated by integrating the induced voltages of the appropriate windings. In this paper the PDF is proposed as a functional series including two dimensional Gauss expressions. In order to proper approximation of hysteresis nonlinearity of the tested iron core the first three terms of functional series of the PDF have been used. In the optimization algorithm only initial and descending limiting hysteresis curves Φ(Θ) were utilized. The feedback function for proposed hysteresis model is assumed as third-order polynomial. The hysteresis model has been successfully validated by comparing the calculated and measured results of Φ(Θ) hysteresis curves. This hysteresis model can be used in transient and steady state simulations of tested transformer taking into account the hysteresis phenomenon. The developed hysteresis model can be also used for analysis of the influence of remnant flux on the operation of tested transformer especially in transient states.

In this paper the feedback Preisach hysteresis model is involved in the flux common to all windings vs ampere-turns of all windings. The new PDF is proposed as functional series including two dimensional Gauss expressions. For tested transformer the three first terms of this functional series may be used for proper approximation of hysteresis nonlinearities.