Electromagnetic Converter Research Articles

The electromagnetic calculations of complex motion common magnetic circuit electromagnetic converter

Abstract This document contains results of research on complex motion common magnetic circuit electromagnetic converter characteristic that allows making independent axial and rotary shaft motion. The converter in addition to linear-rotary mechanism consists of two drive rotors and one common magnetic circuit excitator. Such a solution allows to reduce volume of the machine and makes it easier to use. The paper cites design intent and possible structure of the device. Phenomenon of common magnetic circuit adverse effect on correct operation of device is discussed. The concept of using relative error as a way to evaluate the influence of that phenomenon in the torques is discussed. Waveforms of determined relative errors for all possible cases is presented. Furthermore the concept of average relative error is defined and its use as a quantitative method of assessing the degree of common circuit impact is indicated. Definition of relative error ripple factor is given, and its usage is shown. Winding inductance calculation based on free FEM application is shown and its influence on control strategy and power system

3-D Electromagnetic Modeling of EMI Input Filters

In this paper, a novel 3-D electromagnetic modeling approach which enables electromagnetic compatibility (EMC) analysis of power converter systems in an accurate and computationally efficient way is presented. The 3-D electromagnetic modeling approach, implemented in the EMC simulation tool GeckoEMC, is based on two numerical techniques, the partial element equivalent circuit method and the boundary integral method (PEEC-BIM). The developed PEEC-BIM coupled method enables comprehensive EMC analysis taking into account different effects of the PCB layout, self-parasitics, mutual coupling, shielding, etc., which in turn provides a detailed insight into the electromagnetic behavior of power electronic systems in advance to the implementation of hardware prototypes. The modeling features of the GeckoEMC simulation tool for virtual design of electromagnetic interference (EMI) filters and power converters is demonstrated on the examples of a single-phase two-stage EMI filter and a practical EMI filter for a single-phase PFC input stage. Good agreement between the PEEC-BIM simulation and the small signal transfer function measurement results is achieved over a wide frequency range, from dc up to 30 MHz. The EMC simulation environment enables a step-by-step EMC analysis distinguishing the impact of various electromagnetic effects on the EMI filter performance and allowing an optimal EMI filter design.

Analog-to-Digital Converters of Components of a Displacement based on Primary Electromechanical Converters

Variant implementations of contactless sine-cosine angle-data transmitter and existing dataware positioning solutions based on primary electromagnetic converters are considered. A description and characteristics of cyclic and tracking displacement transducers with open, closed, and variable structure are presented. Constraints associated with their use are demonstrated.

Hyperbolic metamaterial based on anisotropic Mie-type resonance

A hyperbolic metamaterial (MM) based on anisotropic Mie-type resonance is theoretically and experimentally demonstrated in microwave range. Based on the shape-dependent Mie-type resonance, metamaterials with indefinite permeability or permittivity parameters are designed by tailoring the isotropic particle into an anisotropic one. The flat lens consisting of anisotropic dielectric resonators has been designed, fabricated and tested. The experimental observation of refocusing and a plane wave with ominidirectional radiation directly verify the predicted properties, which confirm the potential application in negative index material and superlens. This work will also help to develop all-dielectric anisotropic MM devices such as 3D spatial power combination, cloak, and electromagnetic wave converter, etc.

Electromagnetic Investigations and Power Converter Efficiency Studies on a Laboratory Made Induction Heating Prototype

In this paper electromagnetic analysis and power converter efficiency has been studied on a laboratory prototype induction heating coil. An electromagnetic field based study was first done for the induction heating coil used in the experimental set-up using available Finite Element Analysis package software (FEMM 4.2). The results of the FEM based study are also used in the choice of the operating frequency depending on the applications. Thereafter verifications are done experimentally on a small-scale laboratory developed setup. The approach to be adopted for choice of induction heating operating frequency and the choice of converter type, based on the efficiency and performance, are also briefly presented here. Oscilloscope traces uphold the accuracy of the practical tests conducted.

Mathematical modeling of the registration process of ultrasonic waves in steel metal rolling by electromagnetictype transducer. Part 2

Based on the proposed approach [part 1] to mathematical modeling of electromagnetic ultrasonic transducer in the reception mode of elastic waves, the expressions for the calculation of electromagnetic type converters by example of registration of radially propagation ultrasonic waves in ferromagnetic plates is obtained.The model situation of registration case of radially propagation Rayleigh waves is considered. The estimation of the velocity of the Rayleigh wave and shear waves propagation for materials with the most common values of Poisson's ratio is given.Reference 7, figures 2, tables 1.

Losses modelling of the electromagnetic and IGBTs converters

In this paper we present a design strategy of a converter to electromagnetic switches, necessary to value the losses of this type of converter. The middle modelling of the losses for the two types of converters, with Insulated Gate Bipolar Transistors (IGBTs) and with electromagnetic switches, for two control laws, shows that the converter with IGBTs presents the fewer losses, but it is less reliable and more expensive.

Energy Harvesting from Mechanical Shocks Using a Sensitive Vibration Energy Harvester

This paper deals with a unique principle of energy harvesting technologies. An energy harvesting device generates electric energy from its surroundings using some kind of energy conversion method. Therefore, the considered energy harvesting device does not consume any fuel or substance. The presented energy harvesting system is used forenergy harvesting of electrical energy from mechanical shocks. The presented energy harvesting system uses a very sensitive vibration energy harvester, which was developed for an aeronautic application at Brno University of Technology. This energy harvesting system is a complex mechatronic device, which consists of a precise mechanical part, an electromagnetic converter, power electronics (power management) and a load (e.g., wireless sensor). The very sensitive vibration energy harvester is capable of usingthe mechanical energy of mechanical shocks and it can harvest useful energy. This energy harvesting system is used with a wireless temperature sensor and measured results are presented in this paper.

Non-destructive control of materials properties by the frequency balanced method with superimposed electromagnetic converters

The paper represents the results of non-destructive control of materials properties by the proposed frequencybalanced method and the achieved analytic dependences for balance frequency calculation. It is shown that the frequency method appreciably decreases the influence of magnetizing current value deviation on the measurement accuracy. The method permits to use the standard digital instrumentation, and the results of measurements slightly depend on the air gap between the workpiece surface and the transducer poles. That additionally increases the sensitivity, resolution and accuracy of materials electromagnetic properties control.

Artificial intelligence based optimization for vibration energy harvesting applications

This paper deals with optimization studies based on artificial intelligence methods. These modern optimization methods can be very useful for design improving of an electromagnetic vibration energy harvester. The vibration energy harvester is a complex mechatronic device which harvests electrical energy from ambient mechanical vibrations. The harvester design consists of a precise mechanical resonator, electromagnetic converter and electronics. The optimization study of such complex mechatronic device is complicated however artificial intelligence methods can be used for set up of optimal harvester parameters. Used optimization strategies are applied to optimize the design of the electro-magnetic vibration energy harvester according to multi-objective fitness functions. Optimization results of the harvester are summarized in this paper. Presented optimization algorithms can be used for a design of new energy harvesting systems or for improving on existing energy harvesting systems.

Coupling electromagnetic (FE) models to multidomain simulator to analyse eletrical drives and complex control systems

Coupling electromagnetic (FE) models to multidomain simulator to analyse eletrical drives and complex control systemsThis work presents the co-simulation approach to the analysis of control systems containing detailed models of electromagnetic and electromechanical converters. In this method of analysis the attention is paid to the whole system and not only to its electromagnetic part. The latter is described by equations resulted from the two-dimensional finite element discretisation of the Maxwell equations, and is coupled weakly with the remaining part of the system. The simulation is carried out in Matlab/Simulink environment wherein the coupling is realised through the S-function. Example results regarding simulation of the operation of the control system of an electrical machine and the operation of a power electronic converter are presented and compared with available reference data.

Power sensitivity of vibration energy harvester

This paper deals with a power sensitivity improvement of an electromagnetic vibration energy harvester which generates electrical energy from ambient vibrations. The harvester provides an autonomous source of energy for wireless applications, with an expected power consumption of several mW, placed in environment excited by ambient mechanical vibrations. An appropriately tuned up design of the harvester with adequate sensitivity provides sufficient generating of electrical energy for some wireless applications and maximal harvested power depends on a harvester mass, frequency and level of the vibration and sensitivity of the energy harvester. The design of our harvester is based on electromagnetic converter and it contains a unique spring-less resonance mechanism where stiffness is provided by repelled magnetic forces. The greater sensitivity of the harvester provides more generated power or decrease of the harvester size and weight.

Static and dynamic characteristics of the multilayer electromagnetoelastic converter in nano- and microdrives

A generalized structural and parametric model of a multilayer electromagnetic converter is constructed, and the influence of the geometric and dynamic parameters of the converter and the external load on the static and dynamic characteristics is obtained. The transfer functions of the multilayer electromagnetoelastic converter for electromechanical nano- and microdrives are determined.

A neglected stepchild?

In the light of the continually increasing complexity of design requirements on electromagnetic energy converters, integration of 1) modeling and problem formulation and 2) the optimization including selection of an optimization code seem to be a still widely uncovered but promising field. The mathematical reformulation of otherwise well-known analytical equations to take advantage of a powerful global deterministic optimization technique, in this case, convex optimization, was illustrated. The example cases were the optimization of several performance criteria of a BLDC permanent magnet motor with the use of soft magnetic composites and 3-D flux distribution. The results can be considered as elements of a library of tools leading toward a more reliable and efficient optimization of electromechanical energy converters.

Design and implementation of mechanical resonators for optimized inertial electromagnetic microgenerators

This work describes the design and implementation of an electromagnetic inertial microgenerator for energy scavenging from ambient vibrations. The structure of the device is based in a mechanical resonator formed by a permanent magnet (inertial mass) mounted on a polymeric membrane, in combination with a fixed micromachined coil. ANSYS simulations are carried out to investigate the influence of the resonator geometry on the resonant frequency and on the parasitic damping, and to analyze the optimum geometry of the coil for optimization of the electromagnetic coupling in the devices. Generator prototypes have been fabricated with a modular manufacturing process in which the electromagnetic converter and the mechanical resonator are manufactured separately, diced and then assembled. The experimental results show the ability of these devices to generate power levels in the range of 50 μW with output voltages in the range of hundreds of mV. The parasitic damping of the resonator structures is estimated from the fitting of the experimental data, and suggests the existence of an intrinsic limitation of the polymers related to spring stiffening effects at large excitation amplitudes. The comparison of the simulations and the experimental results indicate that further optimizations of this parameter and of the coil series resistance would allow increasing the generated power in more than one order of magnitude.

Development of battery – driven electromagnetic flow converter

The mean parameter of battery-driven electromagnetic flow converter s is power consumption. Stronger signal, when magnetic field is the same, could be obtained, using channel of rectangular cross-section with wide electrodes. Magnetic circuit should be designed in the way that transmission coefficient would be as big as possible. Power consumption can be reduced, decreasing relative measurement interval and excitation current, but the parasitic signals shows up. Effectiveness of filtration of every pulse of electrode signal must be maximal. To heave a mean the composition of noise of signal, for filtering the best variant is Wavelet filters. During the examination, there was determined that the best is to use 4-leveled sets of filters. Ill. 11, bibl. 4 (in English; summaries in English, Russian and Lithuanian).

The Study of the Operation Modes and Control Strategies of an Advanced Electromechanical Converter for Automobiles

To enhance the performance of hybrid electric vehicle and continuously variable transmission, and to achieve more varied operation modes, a novel breed of integrated electromechanical converter is presented, such as electrical variable transmission (EVT) and four-quadrant transducer. Synthesizing two electric machines, they are essentially electromagnetic theory-based converters with the function of speed, torque, and energy regulation. The feature of flexible and variable control makes them very suitable for use in automobiles, especially in hybrid electric vehicles, as a continuously variable transmission and integrated starter and generator. Furthermore, the operation of the internal combustion engine is optimized, and the reduction of fuel consumption and the improvement of vehicle performance are also achieved. Corresponding to different road loads and driver demands, several operating states and control strategies are possible. Based on a simplified structure, the mathematical model of the EVT has been built, and its power flow and control strategies under different operation modes, are also analyzed

Selection of the Magnetic Circuit Design for Electromagnetic Fluid Flow Converter with Rectangular Channel

Technological advantages are the main cause of popularity of electromagnetic fluid flow converters with cylindrical channel. But electrode signal of electromagnetic fluid flow converters with rectangular channel sensors has the significantly lower dependence on a velocity profile in the cross-section of the channel. Sensitivity of electromagnetic fluid flow converters with rectangular channel is higher. It is showed, that using the same magnetic field excitation coils with the same current, the electromagnetic flow converters with rectangular channel has more than 1.5 times sensitivity, than the electromagnetic flow transducers with cylindrical channel. The sensitivity increases, when ratio between high and base of channel rectangular cross-section decreases. There are better to use rectangular magnetic core in the electromagnetic flow converters with rectangular channel, directing the longer side of core cross-section perpendicularly to channel axis. The magnetic material, needed for core manufacturing, can be diminished till two times comparing with cylindrical core in this case, when the magnetomotive force is the same. By simulation, using finite element method, the magnetic cores of rectangular and circular shapes were compared in the electromagnetic flow converters with perpendicular channel. In the flow transducers with rectangular core shape the sensitivity dependence on velocity profile is significantly lower. Using core of perpendicular shape with longer side 2.33 times more than shorter side in the range of average velocity 0-8m/s the variation of sensitivity is not exceeded of limits [-0.28%, 0.31%]. Using core of perpendicular shape with longer side 1.66 times more than shorter side in the range of average velocity 2-8m/s the variation of sensitivity is not exceeded of limits ±0.03%. By widening the electrodes, the variation of sensitivity can be diminished in the range of average velocity 0-8m/s. Ill.3, bibl.3 (in English; summaries in English, Russian and Lithuanian).

Analysing the dynamics of regulated converters

The characterisation of regulated converters is addressed to enable the assessment of the stability, performance, supply and load interactions as well as transient responses. A canonical model of a converter is proposed and used to create a set of parameters that are able to fully describe the dynamics associated with a converter and therefore can be used to predict the dynamical behaviour of the converter to in changes in source and load interactions. System theory is used to develop methods to study the internal stability of cascaded subsystems such as an electromagnetic interference filter, load and converters. A framework is established that allows the evaluation of different converter topologies under different operation and control modes.

The System of Self-Control of Electromagnetic Flow Meter

The system of self-control of electromagnetic flow converter was created. It permits to control the stability of magnetic flux density in the duct of flow meter, the conductive sediments on the duct walls, the nonconductive sediments on electrodes and diminution of resistance between electrodes and ground potential. The stability of magnetic flux density is watched using the coil mounted on the surface of duct coaxial with magnetic field excitation coils. The conductive sediments on internal walls of duct are watched creating electric current between the electrodes and measuring the magnetic field on the surface of duct. The current of ultrasonic frequency is used. If the 1 % of current is flowed across the sediments the magnetic flux is varied of 11 %. The nonconductive sediments on electrodes and variation of resistance between electrodes and ground potential are watched creating the current between the electrodes and serial connected testing resistance and measuring the voltages of electrodes. Ill. 5, bibl. 6 (in Lithuanian, summaries in Lithuanian; English, Russian).