Linear Inductor Research Articles

Calculating Distributions of Pulsed Magnetic Fields under Hysteretic Interference

Calculations are presented for the distributions of electric voltage readings U(x) from a magnetic field transducer that correspond to the distributions of residual magnetic fields that emerge in a magnetic carrier acted upon by pulsed magnetic fields of different polarity from a linear inductor. The graphs have been produced using Delphi programming language. The phenomenon of magnetic field hysteretic interference (HI) in a magnetic carrier with hysteresis loops described by the dependences in the form of an arctangent has been used to inspect objects made of electroconductive materials, thus improving the accuracy of inspection by several times.

A Locally Active Memristor and Its Application in a Chaotic Circuit

In this brief, we propose a novel locally active memristor based on a voltage-controlled generic memristor model and use the analysis methods of standard nonlinear theory to analyze its characteristics and illustrate the concept of local activity via the dc v-i loci of memristor and non-volatile memory via the power-off plot of memristor. A chaotic attractor is observed with a simple nonlinear circuit that only includes three circuit elements in parallel: 1) a nonlinear locally active memristor; 2) a linear passive inductor; and 3) a linear passive capacitor. Then, we analyze the dynamical characteristics of the above circuit and show complex bifurcation behaviors.

Study of capacitance nonlinearity in nano-scale multi-stage MOSFET-only sigma-delta modulators

Digital integrated circuits (ICs) can be integrated in low-cost digital CMOS technologies with less number of masks than a mixed-signal CMOS technology. This property, however, limits the access to reliable analog components such as linear capacitors and linear inductors. Regardless of the CMOS process, sigma-delta (ΣΔ) modulation of analog signals can be fulfilled by using ordinary MOS devices as capacitors. Called as MOS capacitors (MOSCAPs), these elements illustrate nonlinear C-V characteristic, although the thin gate oxide layer results a high capacitance per unit area. In this article, we investigate the effect of MOS capacitance nonlinearity on the overall performance of discrete-time sigma-delta modulators. To this end, a behavioral-level model of a MOSFET-only switched-capacitor (SC) integrator is proposed, and enables characterizing the transfer behavior of MOSFET-only modulators. The proposed model is used to analyze the linearity and to select a suitable architecture for the modulator. It helps to decide proper structure of each MOSCAP depending on its significance on the output linearity. In virtue of the new model, behavioral-level simulation of a 1-V 12-bit 20MS/s MOSFET-only 2 + 2 sturdy MASH (SMASH) modulator matches well to circuit-level simulations in 90-nm digital CMOS technology. For a −1.4 dB, 19.7 kHz input and an oversampling ratio of 16, the modulator achieves over 72 dB signal-to-noise plus distortion ratio (SNDR), only 3 dB lower than a conventional design based on linear metal-insulator-metal (MIM) capacitors.

Measuring of plasma’s velocity in electrodynamic railgun using high-frequency method

A method is proposed for measuring the velocity of a moving plasma in an electrodynamic railgun in the part of internal ballistics. The achieved result is to provide a measurement of instantaneous velocity and an increase of the safety level for operation of measuring devices. The method is based on the excitation of the rail system of railgun high frequency electric oscillations during in due motion of plasma and creates current resonance. Then is continuously measured cyclic resonance frequency, and the instantaneous velocity of the plasma is determined by a formula, that consist of the current time, the cyclic resonance frequency, equivalent inductance of the power supply of railgun, linear inductance and rail length, and as well used as a model of measurement measure capacitance of capacitor, connected in parallel to rail of railgun grounded from one side. Application of plasma velocity measuring method is suitable for the highly-accurate control of plasma acceleration and pushed it to the railgun bodies with controlled acceleration, requiring measurement during movement of the plasma instantaneous values of velocity.

Tutorial: Experimental Nonlinear Dynamical Circuit Analysis of a Ferromagnetic Inductor

We analyzed ac electrical measurements of a ferromagnetic inductor as a dynamical nonlinear circuit element and observed a pinched hysteresis loop in the plot of the time derivative of its current di/dt versus voltage v. Using the classifications of Chua, we constructed a model of an ideal voltage-controlled non-linear (-1,0) element to compare with the measured characteristics. Deviations of the ideal model from the experimental data indicated the presence of a second state variable or parameter, identified as temperature, which depends upon the power dissipated in the inductor. After installing a normal linear inductor in parallel with the ferromagnetic inductor, the latter displayed two regions of negative differential inductance accompanied by a significant decrease in power dissipation, while the former displayed a sharp negative power spike. We provide a simple extension of the ideal model that agrees well with the experimental data.

Numerical and experimental study of the traveling magnetic field effect on the horizontal solidification in a rectangular cavity part 2: Acting forces ratio and solidification parameters

In recent decades, many phase change processes in metals have been optimized using traveling magnetic fields due to a better understanding of their electromagnetic impact in such applications. In this paper, numerical and experimental study of the effect of traveling magnetic field on the solidification process was evaluated. A three-dimensional numerical model based on the multi-domain method was used to analyze the process of gallium horizontal solidification under the electromagnetic impact in a laboratory-size rectangular cavity. A linear inductor creating traveling magnetic field was designed and built for appropriate measurements and validation the calculations. The analysis was focused on the influence of the ratio between the applied electromagnetic forces and natural convective forces on the solidification front location and shape and on the velocity field. Since the overall electromagnetic force impact on the melt reduced during the solidification, when the melt area was converting into a solid, a new approach to control the solidification parameters was analyzed. In this approach, the value of electromagnetic force acting on the remaining melt during the process was maintained. The main result is the development and improvement of an effective tool for the analysis of direct solidification parameters.The experimental setup included an ultrasonic Doppler velocimeter (UDV) for noninvasive measurements of the velocities in the liquid part of the metal and the liquid-solid interface position, its profile and displacement. All important characteristics of the process were measured, and the results of computations agreed well enough with experimentally obtained data.

Ferroresonance Signal Analysis with Wavelet Transform on 500 kV Transmission Lines Capacitive Voltage Transformers

This paper deals with ferroresonance detection on an transmission line utilizing wavelet transform. The ferroresonance involving linear capacitor and non-linear inductor was triggered by the disturbances of power system, such as lightning strike, switching operation and ground fault. The primary voltage of capacitive voltage divider (CVT) was observed as response of the triggered ferroresonance. The voltage signal was processed using wavelet daubechies (db5) until 9 levels. The cyclic cumulative energy for each condition was then calculated and compared. The result shows that the cyclic cumulative energy ratio and duration of period of cumulative energy deviation can be used as ferroresonance detection parameters.

Coexisting Oscillation and Extreme Multistability for a Memcapacitor‐Based Circuit

The coexisting oscillations are observed with a memcapacitor‐based circuit that consists of two linear inductors, two linear resistors, and an active nonlinear charge‐controlled memcapacitor. We analyze the dynamics of this circuit and find that it owns an infinite number of equilibrium points and coexisting attractors, which means extreme multistability arises. Furthermore, we also show the stability of the infinite many equilibria and analyze the coexistence of fix point, limit cycle, and chaotic attractor in detail. Finally, an experimental result of the proposed oscillator via an analog electronic circuit is given.

High-Power RF Generation From Nonlinear Transmission Lines With Barium Titanate Ceramic Capacitors

In recent years, nonlinear transmission lines (NLTLs) have been investigated for high-power radio frequency generation. High-power waves produced using NLTLs can be applied in mobile defense platforms and satellite communications as they can reach tens of MW of peak power. Their principle of operations is based on the nonlinearity of inductive and/or capacitive lumped elements used in such lines. In this paper, an NLTL using commercial ceramic capacitors as nonlinear elements and linear inductors was simulated and built. Experimental and simulated results show good agreement, validating the model of ceramic capacitors. The frequency obtained from soliton generation at the output of the line was about 4 MHz with peak power of the order of 8 kW.

Determining parameters of electric drive of a sleeper-type turnout based on electromagnet and linear inductor electric motor

As a result of the conducted study, we determined parameters of the electric drive of a sleeper-type turnout based on the linear electromagnetic energy converters. By parameters of the electric drive we mean not only the design of a linear electric motor, such as diameters of stator, anchor, their length, the magnitude of air gap, the type of coil, but also availability of additional elements. In this case — availability of the springs that ensure the required force at the motion start. In this case, two variants of the linear motors design were considered and various layouts of electric drive of a turnout, respectively. In both cases, the force from the motor is transmitted directly to the coupling rod between the rail points, which makes it possible to exclude such an additional element as the reducer, which has a relatively low performance efficiency, additional metal consumption and overall size, which also decreases general reliability of the device as a whole. The problem of multicriterion optimization of parameters of electric motors was compiled. Geometric dimensions of the drives were accepted as the variable parameters. The analysis revealed that the best result in the search for global optimum out of 11 variants were demonstrated by the Weyl method (with the mean-square deviation of 680.9N for electromagnet) and the method of cyclic minimum (with the mean-square deviation of 1052.3N for induction motor). The estimation was performed according to results of the optimal (minimal) value of the mean-square deviation of electromagnetic force from the resistance force. As the load we used the 1/22 type of a turnout with the maximum weight of rail points for the Р65 rail. The data of the study are necessary for creating a new class of electric drives of the turnouts, which make it possible to increase the performance efficiency of the device, as well as its performance speed and, in doing so, to contribute to fulfillment of the program of implementation of high-speed traffic in Ukraine. As a result of the studies, it was found that it is expedient to use the proposed systems of electromagnetic energy converters as the new type of source of mechanical energy in the turnout.

Braking of the Linear Multipositional Electric Catapult

This paper investigates the issues on modern automated flexible operations. The specified requirements have to be satisfied when operating flexible manufacturing systems. The multiinducting linear drives with immobile inductors and a short moving secondary unit could assist the solution of the problem. The functional scheme and structure of the mentioned above system is developed in this paper. The drive is composed of few linear induction motor inductors with a short secondary unit moving between them from one position to another. The procedure of braking of the unit has hardly ever been studied in the scientific research works. The method of spectral analysis is applied for the investigation of the braking procedures. The findings regarding the spectral characteristics of the density of the current of braking are defined.

Study of bifurcations and chaos in the Muthuswamy–Chua system

The dynamical behavior of an autonomous simplest electronic circuit that consists of three elements connected in series governed by three ordinary differential equations was investigated. The circuit elements are a linear passive inductor, a linear passive capacitor, and a nonlinear active memristor. Under variation of two parameters we observed a rich variety of bifurcation phenomena, including periodic, quasi-periodic, intermittent, and chaotic behaviors associated with this very simple nonlinear system. One and two-parameter bifurcation diagrams were studied. Route of period-doubling to chaos through different structures was observed. Our theoretical results are compared with the available experimental results and are found to be in good agreement with these results.

Computer-assisted methods for finding pulsed magnetic-field distributions near current-conducting objects

Time dependences are given for an electric voltage U(t) that is recorded across an inductive magnetic head when scanning a discontinuous magnetic carrier that has been subjected to pulsed magnetic fields of a linear inductor. The value of U(t) at each point of the carrier is determined by the amplitude of each pulse, the pulse direction, and the sequence of exposures. If a current-conducting object is present, this value also depends on the field pulse rise time. The phenomenon of hysteretic interference of a pulsed magnetic field (HI) is used. Digital images of pulsed magnetic fields, as well as computer-assisted methods for measuring these fields, finding their distributions, and processing observation results are presented.

A Highly Linear CMOS Active Inductor and Its Application in Filters and Power Dividers

A high linearity active inductor with a maximum measured Q of 70 and an input 1 dB compression point (Pin, 1dB) of + 8 dBm (associated with a 10% increase in inductance from its small signal value with higher input power) is presented in 180 nm CMOS. Applications of such an inductor in extending the Pin,1 dB of a Wilkinson power divider and a fully integrated second order capacitively coupled bandpass filter for blocker tolerant receivers are also demonstrated. Up to an input power of + 5 dBm, the power divider is seen to have a measured insertion loss (S21) of dB. In each case, to the best of our knowledge, this work reports the highest measured Pin,1dB.

Экспериментальные исследования модели МГД-перемешивателя с постоянными магнитами для алюминиевых печей

A m odel experimental set-up was built aiming to ensure achievable similitude to large scale metal melting furnaces, where electromagnetic stirring is required to reduce the melting time and to achieve thermal and compositional uniformity. The widely used three-phase AC current linear travelling magnetic field inductor is substituted by a new energy-saving concept of a Permanent-Magnet (PM) inductor, consisting of a multitude of cylindrical dipoles, which form a Halbach array and are rotated synchronously. The stirrer creates a very unstable time-dependent flow pattern in the liquid metal pool. The turbulent local velocity was measured, delivering experimental data about time-averaged flow and turbulence intensity as well. Spatial components of velocity were measured by ultrasound Doppler anemometry and by a potential difference probe with an incorporated permanent magnet, delivering mutually verifying and complementary data with higher reliability. The experimental data might be used to validate the full three-dimensional numerical simulations of the stirring produced in actual large scale metal melting furnaces Normal 0 false false false RU X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:Обычная таблица; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:Calibri,sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

Hopf Bifurcation and Chaos in Simplest Fractional-Order Memristor-based Electrical Circuit

In this article, we investigate the bifurcation and chaos in a simplest fractional-order memristor-based electrical circuit composed of only three circuit elements: a linear passive capacitor, a linear passive inductor and a non-linear active memristor with two-degree polynomial memristance and a second-order exponent internal state. It is shown that this fractional circuit can exhibit a drastically rich non-linear dynamics such as a Hopf bifurcation, coexistence of two, three and four limit cycles, double-scroll chaotic attractor, four-scroll chaotic attractor, coexistence of one (or two) chaotic attractor with one limit cycle and new chaotic attractor which is not observed in the integer case. Finally, the presence of chaos is confirmed by the application of the recently introduced 0–1 test.

Delocalized periodic vibrations in nonlinear LC and LCR electrical chains

We consider electrical LC- and LCR-chains consisting of N cells. In the LC-chain each cell contains a linear inductor L and a nonlinear capacitor C, while the cell in the LCR-chain include additionally a resistor R and an voltage source. It is assumed that voltage dependence of capacitors represents an even function. Such capacitors have implemented by some experimental groups studying propagation of electrical signals in the lines constructed on MOS and CMOS substrates. In these chains, we study dynamical regimes representing nonlinear normal modes (NNMs) by Rosenberg. We prove that maximum possible number of symmetry-determined NNMs which can be excited in the considered chains is equal to 5. The stability of these modes for different N is studied with the aid of the group-theoretical method [Physical Review E 73 (2006) 36216] which allows to simplify radically the variational systems appearing in the Floquet stability analysis. For NNMs in LC-chain, the scaling of the voltage stability threshold in the thermodynamic limit (N→∞) is determined. It is shown that the above group theoretical method can be also used for studying stability of NNMs in the LCR-chains.

Novel chaotic behavior in the Muthuswamy-Chua system using Chebyshev Polynomials

In this paper, three kinds of memristors with memristance functions obtained from the Chebyshev polynomials are used in the Muthuswamy-Chua system, which has only three circuit elements: a linear passive inductor, a linear passive capacitor and a nonlinear active memristor. We use multivariable second-order polynomial functions of current and memristor state for the internal state function of the memristor. This enables our system to generate not only double-scroll but also four-scroll attractors. Systematic studies of chaotic behavior in these systems are performed using phase portraits, bifurcation diagrams and Lyapunov exponents. Simulation results show that all these systems exhibit chaotic behavior over a range of control parameters. Copyright © 2014 John Wiley & Sons, Ltd.

Chaotic behavior in fractional-order memristor-based simplest chaotic circuit using fourth degree polynomial

In this paper, a memristor with a fourth degree polynomial memristance function is used in the simplest chaotic circuit which has only three circuit elements: a linear passive inductor, a linear passive capacitor, and a nonlinear active memristor. We use second order exponent internal state memristor function and fourth degree polynomial memristance function to increase complexity of the chaos. So, the system can generate double-scroll attractor and four-scroll attractor. Systematic studies of chaotic behavior in the integer-order and fractional-order systems are performed using phase portraits, bifurcation diagrams, Lyapunov exponents, and stability analysis. Simulation results show that both integer-order and fractional-order systems exhibit chaotic behavior over a range of control parameters.

Modulational Instability in a Pair of Non-identical Coupled Nonlinear Electrical Transmission Lines

In this work, we investigate the dynamics of modulated waves non-identical coupled nonlinear transmission lines. Traditional methods for avoiding mode mixing in identical coupled nonlinear electrical lines consist of adding the same number of linear inductors in each branch. Adding linear inductors in a single line leads to asymmetric coupled nonlinear electrical transmission lines which propagate the signal and the mode mixing. On one hand, the difference between the two lines induced the fission for only one mode of propagation. This fission is influenced by the amplitude of the signal and the amount of the input energy as well; it also narrows the width of the input pulse soliton, leading to a possible increasing of the bit rate. On the other hand, the dissymmetry of the two lines converts the network into a good amplifier for the ω_ mode which corresponds to the regime admitting low frequencies.