Showing papers in "Compel-the International Journal for Computation and Mathematics in Electrical and Electronic Engineering in 2010"

Simulation of wave propagation effects in machine windings

Abstract: Purpose – The purpose of this paper is to offer a simulation method for predicting the impedance of machine windings at higher frequencies.Design/methodology/approach – A transmission‐line model (TLM) is developed based on parameters calculated on the basis of electroquasistatic and magnetoquasistatic finite‐element (FE) model of the winding cross‐section.Findings – The FE formulations for the low‐ and high‐frequency limits give acceptable results for the respective frequency ranges. An eddy‐current formulation is only accurate on a broader region when the FE mesh is sufficiently fine to resolve the skin depth.Research limitations/implications – The paper is restricted to frequency‐domain simulations.Practical implications – The results of the paper improve the understanding of higher‐frequency parasitic effects in electrical drives with long windings.Originality/value – The paper shows the limitations of the FE methods used for determining the parameters of the TLMs and remedies to avoid these.

Proposal of electromagnetic spherical actuator with 3‐DOF

Abstract: Purpose – The purpose of this paper is to propose a new electromagnetic spherical actuator with three‐degree‐of‐freedom. Multi‐degree‐of‐freedom actuators which can be operated in arbitrary axis come to attract attention because of the solution for efficiency, weight, size, and so on. Particularly, spherical actuators are studied as the application to the joints and eyeballs for robots because they can be freely rotated in every axis direction.Design/methodology/approach – The paper proposes a new electromagnetic spherical actuator with three‐degree‐of‐freedom in rotation, and the torque characteristics of the actuator are computed by the 3D finite element method (FEM). The validity of the computation is confirmed through the measurement of a prototype.Findings – It is found that this actuator realized the high torque of more than 1.0 Nm in every axis circumference.Originality/value – A new spherical three‐degree‐of‐freedom actuator is proposed. The torque characteristics of the improved model are calcula...

Vibration analysis of small power transformer

Abstract: Purpose – The purpose of this paper is to present a methodology of identification and calculating vibrations of power transformers caused by magnetostriction.Design/methodology/approach – All calculations are based on finite element approach. Electromagnetic model uses 2D time stepping solution in nonlinear continuum of the core accompanied with equivalent representation of overlapping areas. Structural model is 3D with special representation for laminated core limbs. Theoretical results are compared with experimental ones obtained as operational deflection shapes from vibration measurements.Findings – Tensor representation of magnetostriction stress enables calculation of equivalent forces acting on arbitrary chosen parts of laminated core. These forces converted into amplitude and phase of Fourier spectrum and introduced into structural model make possible to get displacement field with reasonable accuracy.Research limitations/implications – Assumption of magnetic isotropy of the transformer core is the...

Skin effect experimental validations of induction motor squirrel cage parameters

Abstract: Purpose – The paper deals with the experimental validations of the corrective coefficient used to take into account the skin effect in the equivalent circuit rotor resistance of induction motors with squirrel cages.Design/methodology/approach – Locked rotor tests have been performed at several supply frequencies on different induction motors; the collected experimental data have been used to validate the rotor parameters analytical estimation obtained by means of a numerical procedure previously proposed by the authors.Findings – The reported analyses regard both open and closed rotor slots. For frequencies up to 80‐100 Hz, the reported comparison between experimental and calculated skin effect corrective coefficients shows that the adopted model allows to get satisfactory results in terms of accuracy, lower than 3 percent for open rotor slot machines. The upper frequency limit has to be judged taking into account the objective difficulties to estimate accurate values of the rotor parameters from experime...

3D analytical field calculation using triangular magnet segments applied to a skewed linear permanent magnet actuator

Abstract: Purpose – The purpose of this paper is to present novel analytical expressions which describe the 3D magnetic field of arbitrarily magnetized triangular‐shaped charged surfaces. These versatile expressions model that the field of triangular‐shaped permanent magnets (PMs) are very suitable to model skewed slotless machines.Design/methodology/approach – The analytical 3D surface charge method is normally used to provide field expressions for PMs in free space. In this paper, the analytical surface charge integrals are analytically solved for charged right‐triangular surfaces. The resulting field is compared with that obtained by finite element modeling (FEM) and subsequently applied in two examples.Findings – The comparison with FEM shows that the 3D analytical expressions are very accurate and exhibit very low‐numerical noise. These fast‐solving versatile expressions are therefore considered suitable to model triangular‐shaped or polyhedral‐shaped PMs.Research limitations/implications – The surface charge ...

Design optimization of three‐phase energy efficient induction motor using adaptive bacterial foraging algorithm

Abstract: Purpose – The purpose of this paper is to present the application of an adaptive bacterial foraging (BF) algorithm for the design optimization of an energy efficient induction motor.Design/methodology/approach – The induction motor design problem is formulated as a mixed integer nonlinear optimization problem. A set of nine independent variables is selected, and to make the machine feasible and practically acceptable, six constraints are imposed on the design. Two different objective functions are considered, namely, the annual active material cost, and the sum of the annual active material cost, annual cost of the active power loss of the motor and annual energy cost required to supply such power loss. A new adaptive BF algorithm is used for solving the optimization problem. A generic penalty function method, which does not require any penalty coefficient, is employed for constraint handling.Findings – The adaptive BF algorithm is validated for two sample motors and benchmarked with the genetic algorithm...

Automated sizing of permanent magnet synchronous machines with respect to electromagnetic and thermal aspects

Abstract: Purpose – 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.Design/methodology/approach – 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.Findings – 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).Practical implications – Sizing, electromagnetic and thermal modeling aspects are integrated into an ...

Forced dynamics control of PMSM drives with torsion oscillations

Abstract: Purpose – The purpose of this paper is to discuss the design and verification of a new control algorithm for the drive with permanent magnet synchronous motor (PMSM) and flexible coupling based on “Forced dynamics control”. Control laws are derived and tested for the rotor and load angle control and achieve non‐oscillatory position step response with a specified settling time.Design/methodology/approach – “Forced dynamics control” is a new control technique based on feedback linearization which forces rotor or load position to follow demanded position with prescribed closed‐loop dynamics. The proposed control structure is developed in two steps: first, the feedback linearisation is applied to the rotor speed and then similar technique is used for position control loop.Findings – The proposed controller is of the cascade structure, comprising an inner speed control loop, respecting vector control principles and outer position control loop designed to control the rotor or load angle, respectively. Estimates...

Instantaneous torque control using flux‐based commutation and phase‐torque distribution technique for SR motor EV

Abstract: Purpose – The purpose of this paper is to propose a new instantaneous torque control method for switched reluctance motor (SR motor) and presents experimental data in electric vehicle (EV) application.Design/methodology/approach – The proposed control method uses two kind of techniques: a flux‐based commutation technique prevents the negative phase torque always. On the other hand, a direct phase‐torque distribution technique gives suitable each phase‐torque command under limited DC voltage. These techniques can track motor torque to the command. These control schemes are implemented on a small processor and a field programmable gate array.Findings – The experimental results of the EV show small torque ripple at low speed on both acceleration and regenerative braking. Changing the parameter of the current stop angle can improve torque ripple at high speed. The proposed method can effectively control motor torque.Practical implications – The proposed method can reduce torque ripple but the implementation i...

Robust Invariant Set-based Protection of Multi-mass Electrical Drives

Abstract: Purpose – The purpose of this paper is to elaborate a robust model‐based protective control algorithm for multi‐mass motor drives that are subjected to physical and safety constraints on their variables.Design/methodology/approach – The algorithm relies on the off‐line computed maximum robust controlled invariant set or its approximation for the given drive system and imposed constraints. It can be used to patch any existing drive control scheme with a firm constraints satisfaction guarantee. The online patch implementation is actually a simple correction of the control signal computed with the existing control scheme, with a mandatory state observer.Findings – Performance of the patch is tested on a two‐mass drive system in combination with classical two‐mass drive speed controllers – P+I and reduced state controller. All constraints violations that exist in the presented responses obtained without the protection patch are suppressed by using the patch which shows the effectiveness of the approach. A bri...

Methods for commissioning and identification in drives

Abstract: Purpose – The purpose of this paper is to summarize several identification methods for the automatic commissioning of electrical drives that are presented in different earlier papers of the same authors. This paper is intended as a contribution to the development of expert systems, taking into account parametric models of the mechanical and electrical subsystem as well as the corresponding parameter fitting.Design/methodology/approach – Some system parameters, which are mandatory for the commissioning of electrical and mechanical systems are often not known. For their identification, a method based on the frequency response calculation utilizing the Welch method is now presented. The main focus of the work is directed to the measurement of the frequency response by exciting the system with pseudo‐random binary signals and to the subsequent procedure for the calculation of the corresponding parameter by utilizing the Levenberg‐Marquardt algorithm.Findings – The presented identification procedure leads to o...

Line-frequency rectifier dc-bus voltage instability analysis and mitigation

Abstract: Use of small dc bus capacitors is desirable in variable-speed drives and distributed power systems as it can reduce the size and improve reliability of the system. However, small dc bus capacitors may lead to instability of the dc bus voltage. Such voltage stability problem can occur when the bus is fed from a PWM rectifier or a line-frequency rectifier. This paper considers the case when a line-frequency rectifier is used and presents a method for the analysis of dc bus voltage instability in such systems. Small-signal input impedance of multipulse line-frequency rectifiers is used in conjunction with the ac source output impedance to detect possible instability on the dc bus. Stabilization of the dc bus voltage by a passive damping is presented and compared to other stabilization methods such as increasing dc bus capacitance or placing the damper at the ac input of the rectifier. Experimental results from a 12-pulse rectifier feeding an electronic load that is programmed to emulate constant-power load behavior typical of DPS and variable-speed drives are presented to validate the analysis and design approach.

An implicit discontinuous Galerkin time‐domain method for two‐dimensional electromagnetic wave propagation

Abstract: Purpose – The purpose of this paper is to develop a time implicit discontinuous Galerkin method for the simulation of two‐dimensional time‐domain electromagnetic wave propagation on non‐uniform triangular meshes.Design/methodology/approach – The proposed method combines an arbitrary high‐order discontinuous Galerkin method for the discretization in space designed on triangular meshes, with a second‐order Cranck‐Nicolson scheme for time integration. At each time step, a multifrontal sparse LU method is used for solving the linear system resulting from the discretization of the TE Maxwell equations.Findings – Despite the computational overhead of the solution of a linear system at each time step, the resulting implicit discontinuous Galerkin time‐domain method allows for a noticeable reduction of the computing time as compared to its explicit counterpart based on a leap‐frog time integration scheme.Research limitations/implications – The proposed method is useful if the underlying mesh is non‐uniform or loc...

Adaptive backstepping controller for linear induction motor position control

Abstract: Purpose – The purpose of this paper is to propose mover position control of linear induction motor (LIM) using an adaptive backstepping approach based on field orientation.Design/methodology/approach – First, the indirect field‐oriented control LIM is derived. Then, an adaptive backstepping approach based on field‐oriented control of LIM is proposed to compensate the uncertainties which occur in the control. Mover position amplitude tracking objective is formulated, under the assumption of unknown total mass of the moving element, viscous friction, and load force, so that the position regulation is achieved.Findings – The effectiveness and robustness of the proposed control scheme are verified by numerical simulation using Matlab/Simulink model. The numerical validation results of the proposed scheme have presented good transient control performances and robustness to uncertainties compared to the conventional backstepping control design.Originality/value – The paper presents an adaptive backstepping appr...

Effects of carrier frequency of PWM inverter on electrical loss of interior permanent magnet motor

Abstract: Purpose – The purpose of this paper is to clarify the electrical loss of an interior permanent magnet (IPM) motor driven by the pulse‐width modulation (PWM) inverter with various carrier frequencies quantitatively.Design/methodology/approach – An IPM motor driven by the PWM inverter was simulated using the three‐dimensional finite‐element method while changing various carrier frequencies of the PWM inverter. The calculated results are compared with the calculated results differing the number of permanent magnet division.Findings – The eddy current loss in the permanent magnets decreases as the carrier frequency increases. In the case of low‐carrier frequency, the eddy current loss greatly decreases as the number of permanent magnet division increases. However, the effect of the eddy current loss decreases by the number of permanent magnet division as the carrier frequency increases.Originality/value – The paper describes the electrical loss of an IPM motor driven by the PWM inverter with various carrier f...

Simulation of skin effect via separated representations

Abstract: Purpose The purpose of this paper is to apply the method of separation of variables to obtain the current distribution in the slot of an electrical machine, taking into account the skin effect Design/methodology/approach A slot in an electrical machine, filled with a solid conductor, and fed with an externally imposed density current, presents a current distribution that depends on the skin effect The magnetic potential vector is formulated and solved using a separate representation as a finite sum of unidimensional (space and time) functions, taking into account the boundary conditions The proposed method obtains the transient and permanent distribution of the current in the interior of the slot, both in transient and steady regime, and the results at the end of the transient are compared with the analytic ones in permanent regime Findings The magnetic potential vector in the interior of a slot filled with a solid conductor can be expressed as a finite sum of just 16 modes, which capture the evolution of the field during the transient and permanent regime These modes are expressed as the product of space and time functions, which have been obtained automatically by the separation of variables algorithm Instead of solving multiple field problems, one for each time instant, the proposed method just solves two single variable differential equations, one in the time domain and other in the spatial one Research limitations/implications The application of the proposed method to non sinusoidal currents, such as those generated by variable speed drives, would allow to compute the field taking into account both the very small time scale of the pulse width modulation pulses, in the range of kiloHz, and the wide time scale of the currents envelope, in the range of 0 100 Hz Extension to 2D and 3D spatial configurations is also under consideration Originality/value Using the method of separation of variables to solve electromagnetic problems provides a new method which can simplify and speed up the computation of transient fields in multidimensional time and space domains

Analytical thermal models for small induction motors

Abstract: Purpose – Thermal analysis is an important design aspect and becoming a more important component of the electric motor design process due to the push for reduced weights and costs and increased efficiency. The purpose of this paper is to demonstrate that the accuracy of analytical thermal models depends on the accuracy of the thermal resistance computation and on the number of nodes in the equivalent thermal circuit.Design/methodology/approach – In this paper, several thermal analytical models with different numbers of nodes are compared against with each other and with experimental data.Findings – It is demonstrated that the more sophisticated and detailed model having a larger number of nodes can be used to calibrate the simpler but faster models with less nodes. The models are all for the same range of small totally enclosed non‐ventilated induction motors.Originality/value – This paper shows that simplified and/or detailed analytical thermal models can be successfully used in predicting the temperatur...

A modified elliptic model of anisotropy in nonlinear magnetic materials

Abstract: Purpose – Grain‐oriented steel has a distinctly anisotropic and nonlinear behaviour. Only in rare cases is the magnetisation curve known for directions other than the principal ones. The paper aims at providing a model to obtain these curves for any direction if those in the easy and hard directions are only given.Design/methodology/approach – The well‐known elliptic model is modified in order to correctly mimic the typical behaviour of grain‐oriented steel which is not described correctly by the original elliptic model. An additional condition is introduced to fix the angle between the flux density and magnetic field intensity.Findings – The model is found to yield good agreement with measurements in case of a special material for which measured curves for intermediate angles are available.Research limitations/implications – Further research is necessary to establish whether the model is applicable to other materials.Originality/value – The new model can be used in numerical analyses of devices comprisin...

Identification of electrical parameters in a power network using genetic algorithms and transient measurements

Abstract: Purpose – The knowledge of power network parameters (which are usually unknown or poorly quantified and cannot be measured directly) is very valuable for power system modelling, simulation, protection and control; since it is fundamental for solving many problems such as minimizing the effect of voltage distortion, active filter control or relay setting. The purpose of this paper is to develop a new, easy, effective and reliable method for power network parameters identification.Design/methodology/approach – The proposed identification method is based on current transient injections performed by a pulse width modulated power converter (which can be a rectifier or an active filter already installed in the network) and the analysis of the resultant network voltage response at the point of common coupling using genetic algorithms optimization.Findings – Simulation tests show the effectiveness of the proposed identification strategy achieving negligible errors, even in practical conditions when measurement no...

A study on QCM sensor for identification of acetone vapor

Abstract: Purpose – The purpose of this paper is to show how a quartz crystal microbalance modified with poly (epichlorohydrin) (PECH) is fabricated and used for detection of acetone vapor using a spin‐coating method.Design/methodology/approach – Measurements are based on the frequency shifts due to the adsorption of acetone vapor on the surface of the modified electrodes. A first‐order linear time‐invariant (LTI) system model is used to simulate the sensor response.Findings – It is found that frequency shifts are linear to the concentrations of analyte, and cycle test examination shows good repeatability. The sensitivity to acetone vapor is better than other volatile compounds. A good match result is obtained with the LTI system model.Originality/value – The device performance opens a potential way for analyzing acetone vapor.

Electric motor winding temperature prediction using a simple two‐resistance thermal circuit

Abstract: Purpose – The purpose of this paper is to propose a simplified thermal circuit to estimate the temperature rise in the winding of a totally enclosed fan cooled electric motor for different loads and/or cooling conditions since the motor has already been tested for a known condition.Design/methodology/approach – The determination of the convection resistance is based on classical Nusselt correlations and the value of conduction resistance is provided from a known load condition and the corresponding temperature rise in the winding.Findings – Predicted temperature values showed good agreement with the experimental results, demonstrating that the hypothesis of simplification to a punctual source of thermal energy is acceptable.Research limitations/implications – It is necessary that the motor has already been tested for a known condition (losses, temperature, and ventilation). Although the basic idea of this methodology is based on the use of a reference test condition of the same motor, as a suggestion, wit...

Sound optimization of a converter‐fed drive system using an acoustic camera in combination with modal analysis

Abstract: Purpose – Modern variable‐speed drive systems using frequency converters generate additional audible noise as a result of the voltages that are no longer sinusoidal. Using suitable measures, the purpose of this paper is to find an optimum for minimum noise radiation in the complete drive system.Design/methodology/approach – The main areas to concentrate on to achieve an optimum are the source of excitation itself – the frequency converter, as well as the actual source of the noise, the motor. Optimization measures are drawn‐up using soundscaping with subsequent modal analysis of the actual state. The effectiveness of any changes made can be estimated using simulation techniques. This approach is confirmed by subsequently implementing the selected measures and verifying them by performing the appropriate measurements.Findings – The paper takes care of the increasingly important field of converter‐fed drive systems and their special acoustical challenge. It shows a practical way to reduce audible noise comb...

Input‐output nominalization of linear systems with slow‐varying uncertainties

Abstract: Purpose – The purpose of this paper is to present a method to compensate slow varying disturbances and plant parameter drifts using a simple yet robust algorithm called input‐output nominalization.Design/methodology/approach – In case of known uncertainties, an analytical expression of pre‐computed feed‐forward compensation command is derived. In presence of unknown disturbances and parameter drifts, the control algorithm uses a proportional‐integrative estimator‐based nominalizer. It creates a nominalizing signal, reflecting the deviation of the system from its nominal form using plant input and output. The signal is subtracted from the nominal controller output to cancel the uncertainty and disturbances effects.Findings – As a result, the uncertain plant and the nominalizer quickly converge to the nominal plant. Therefore, a simple controller tuned according to the nominal plant can be used despite the disturbances and parameter drifts and a nominal response is always obtained. Simulation and experiment...

Voltage distribution along a long ceramic insulator string in a high‐voltage tower window

Abstract: Purpose – The purpose of this paper is to introduce an efficient model for analysis of the voltage distribution along the long ceramic insulator strings in a high‐voltage tower window, especially when the structure and parameters of the ceramic insulator are unknown. The effect of the grading ring on the voltage distribution is also investigated.Design/methodology/approach – A circuit model composed of capacitors is used to analyze the voltage distribution along the ceramic insulator strings in a transmission tower window. The capacitances of the disk insulators, line conductors, and tower are obtained by using the finite element method, charge simulation method, boundary element method, and measurement according to their characteristics.Findings – The model is very efficient. The voltage distribution along insulator strings can be optimized by adjusting the parameters of the grading ring. The maximum amount of voltage applied to a single insulator disk can be reduced effectively by increasing either the ...

A numerical evaluation of electromagnetic fields exposure on real human body models until 100 kHz

Abstract: Purpose – The purpose of this paper is to describe how numerical models of human body have been applied for the evaluation of current density induced by strong magnetic field, to verify the respect of the basic restriction proposed by International Committee Non Ionizing Radiation Protection (ICNIRP) guidelines.Design/methodology/approach – Finite element method has been used in order to compute the induced current density in a suitable human body model and a simplified model – a homogeneous cylinder – due to a time‐varying magnetic field.Findings – In the practical case of a resistance welding equipment, the implemented computational technique has been used in order to evaluate both the magnetic flux density and the induced current density in different tissues. Their values have been also compared with the ones obtained in a homogeneous cylinder.Practical implications – The proposed method can be used in order to evaluate the compliance of the magnetic field produced by resistance welding equipments with...

Computer models of 3D magnetic microfibres used in textile actuators

Abstract: Purpose – The purpose of this paper is to discuss the idea of designing and manufacturing intelligent clothes with magnetic fibres. The main goal of the research is to create the universal generator of computer structural models for whole bundles of magnetic microfibres.Design/methodology/approach – The paper presents the algorithm of magnetic microfibers computer modelling. It covers both finite element method (FEM) and reluctance network method. This paper deals with creating 3D computer structural models of magnetic microfibres, which could be introduced as the textile magnetic sensors or actuators. Because of very complicated 3D microfibres structure, it is hoped that the quickest possible method can be found to solve the problem.Findings – The results focus on the methodology presented in the paper which can be implemented in building 3D equivalent B/H curve of the microfibers set by using the field method – combining reluctance network method and FEM. Defining the proper magnetic B/H curves of magne...

Fixed‐point method for solving non linear periodic eddy current problems with T, Φ‐Φ formulation

Abstract: Purpose – The purpose of the paper is to show the application of the fixed‐point method with the T, Φ‐Φ formulation to get the steady‐state solution of the quasi‐static Maxwell's equations with non‐linear material properties and periodic excitations.Design/methodology/approach – The fixed‐point method is used to solve the problem arising from the non‐linear material properties. The harmonic balance principle and a time periodic technique give the periodic solution in all non‐linear iterations. The optimal parameter of the fixed‐point method is investigated to accelerate its convergence speed.Findings – The Galerkin equations of the DC part are found to be different from those of the higher harmonics. The optimal parameter of the fixed‐point method is determined.Originality/value – The establishment of the Galerkin equations of the DC part is a new result. The method is first used to solve three‐dimensional problems with the T, Φ‐Φ formulation.

Optimal control of current switching angles for high‐speed SRM drive

Abstract: Purpose – The purpose of this paper is to propose a method of optimal control of current commutation of switched reluctance motor drive.Design/methodology/approach – The problem of optimal current commutation control is solved by off‐line selection of switching‐on and switching‐off angles. Selection of optimal values of angles is provided on computer model of the drive with help of particle swarm optimisation method. The optimal angle values are detected as functions of phase current and rotor speed. These calculated optimal values are stored in microcomputer control system memory in form of two‐input look‐up tables. The results are validated on laboratory set up.Findings – Three different criteria of optimal control, which are taken into account: the maximum electromagnetic torque for given reference current, the maximum ratio of electromagnetic torque to root mean square value of phase current and the minimum electromagnetic torque ripples, gave a good results validated by simulation and experimental in...

Energetic model of ferromagnetic hysteresis

Abstract: Purpose – The purpose of this paper is to present a model to describe the nonlinear and hysteretic properties of ferromagnetic materials.Design/methodology/approach – The energetic model of ferromagnetic hysteresis evolved from some well‐known concepts in ferromagnetism in the last years. The magnetisation process is calculated from energy balance and statistical domain behaviour. Based on vectorial, anisotropic, multi‐domain considerations an isotropic, scalar model is derived, which gives quite simple equations to describe the nonlinear, hysteretic magnetisation process.Findings – The presented simulations for steel samples and ferrite samples show very nice correspondence with measurements.Originality/value – The scalar model seems to be especially suited for integration into finite element modelling or into simulations of electro‐magnetic circuits.

Support vector machines for measuring dielectric properties of materials

Abstract: Purpose – The dielectric properties of materials (complex permittivity) can be deduced from the admittance measured at the discontinuity plane of a coaxial open‐ended probe. This implies the implementation of an inversion procedure. The purpose of this paper is to develop a new non‐iterative inversion methodology in the field of microwave characterization allowing reducing the computation cost comparatively to iterative procedures.Design/methodology/approach – The inversion methodology combines the support vector machine (SVM) technique and the finite element method (FEM). The SVM are used as inverse models. They show good approximation and generalization capabilities. FEM allows the generation of the data sets required by the SVM parameter adjustment. A data set is constituted of input (complex admittance and frequency) and output (complex permittivity) pairs.Findings – The results show the applicability of SVM to solve microwave inverse problems instead of using traditional iterative inversion methods w...