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Introduction. This work was initiated by the problems of cardiovascular diseases, which are one of the main causes of mortality of the population of our planet. More than ten years ago, in 2012, approximately 3.7 million people died of acute coronary syndrome worldwide. The fight against such pathologies is carried out with the help of so-called stents, the manufacture of which can be carried out by the method of magnetic pulse «expansion» from hollow metal cylinders. The limited production possibilities of magnetic pulse «expansion» were caused by the minimum cross-sectional size of the inductor-instrument, which can be practically manufactured. Other tools are required to perform this operation. Novelty. A system of magnetic-pulse expansion of thin-walled pipes of small diameter with an inductor that excites an azimuthal electromagnetic field in the case of direct current passing through the processing object and in the absence of its connection in an electric circuit with an inductor is proposed. Purpose. The main analytical dependencies for the characteristics of the electromagnetic processes taking place in the inductor systems for the expansion of cylindrical conductive pipes of small diameter when direct passage of current through the processed object and when it is not connected to an electric circuit with an inductor (insulated billet) is derived. Methods. The solution of the boundary value problem with given boundary conditions was carried out by applying Laplace transforms and integrating Maxwell’s equations. Results. Analytical expressions were obtained for the main characteristics of the processes: the intensities of the excited electromagnetic fields and currents in the system depending on the parameters of the studied systems. The analysis of possible technical schemes for solving the given problem indicated the choice of the optimal variant of an effective system of magnetic-pulse «stretching» of thin-walled cylindrical conductors of small diameter. Practical value. Based on the qualitative analysis of the obtained results, recommendations for the practical implementation of the proposed system were formulated. The obtained dependences allow us to give numerical estimates of the effectiveness of excitation of magnetic pressure forces on the object of processing and to choose directions for further improvement of the magnetic pulse technology for solving such problems. [ABSTRACT FROM AUTHOR]

This article proposes a new interleaved buck converter with a high step-down conversion ratio and soft-switching. The soft-switching conditions for the main IGBTs are achieved with the aid of a simple auxiliary circuit, which comprises a resonant inductor, a resonant capacitor, and a diode. A new interleaved buck converter is realized by adopting two auxiliary circuits separately connected to each one of the legs to provide zero voltage switching (ZVS) and zero current switching (ZCS) turn-on operation. The major advantages of this converter are reduced switching losses, a high step-down ratio, reduced voltage stresses, and no limitation on duty ratio. To validate the theoretical analysis, a laboratory prototype of a 200 V-60 V converter system has been developed and achieved an efficiency of 96% at 250 W output power. [ABSTRACT FROM AUTHOR]

Separation and classification are important operations in particle technology, but they are still limited in terms of suspended particles in the micrometer and nanometer size-range. Electrical fields can be beneficial for sorting such particles according to material properties. A mechanism based on strong and inhomogeneous fields is dielectrophoresis (DEP). It can be used to separate microparticles according to their material properties, such as conductivity and permittivity, by selectively trapping one particle type while the other can pass the separator. Conventional DEP-separators show either a limitation in throughput or frequency bandwidth. A low throughput limits the economical feasibility in many cases. A lower frequency bandwidth limits the variety of materials that can be sorted by DEP. To separate semiconducting particles from a mixture containing particles with higher conductivity according to their material, high frequencies are required. Possible applications are the separation of semiconducting and metallic carbon nanotubes or the separation of carbon-coated lithium iron phosphate particles from graphite in the recycling process of spent lithium-ion batteries. In this publication, we aim to display how to tune the electrical impedance of a high-throughput DEP separator based on custom-designed printed circuit boards to increase its frequency bandwidth. By adding inductors to the electrical circuit, we were able to increase the frequency bandwidth from 500 kHz to over 11 MHz. The experiments in this study act as proof-of-principle. Furthermore, a non-deterministic way to increase the impedance of the setup is shown, yielding a maximum frequency of 39.16 MHz. [ABSTRACT FROM AUTHOR]

Recent years have seen an increase in electrical crises due to the proliferation of automated inductors and electrical applications such as electric vehicles and mobile devices. The greater dispersion in the smart grid exposes it to risks like cyber-attacks, attenuation, and faulty detections that were not prevalent in conventional methods. The proposed machine learning-based renewable energy smart grid protector and controller (ReSGPC) using Kalman filters effectively controls and detects noise faults, cyberattacks, and attenuation, addressing the mentioned problems. Additionally, the proposed method has increased the efficiency of the smart grid due to its superior performance compared to conventional methods. This method provides an additional layer of protection for the system, safeguarding grid information. An optimal control law is developed to ensure the stability of the power network. The controller demonstrates significant improvements in effectiveness regardless of the initial values. Numerical simulations verify the developed approach, showing that the recommended method offers a more powerful line of attack. This strategy provides a crucial energy management framework for the smart grid, representing a reliable and system-based communication infrastructure with applications integrating renewable resources. Performance analysis reveals substantial improvements, with the proposed method achieving an efficiency increase of 0.25%, 0.42%, 0.32%, and 0.34% in Mean Squared Error (MSE) for ∆1, ∆2, ∆3, and ∆4 scenarios respectively, compared to existing methods. [ABSTRACT FROM AUTHOR]

In this paper, a dual-active bridge converter based on the utilization of two transformers is presented. The principles of operation, switching strategy, and transmission power characteristics of the proposed converter under normal operation are discussed, comprehensively. Moreover, the RMS current of two transformers with different values of inductances of the inductors that are in series with the transformers; is discussed. The operation of the proposed dual active bridge (DAB) converter under the open-circuit failure of transformers is studied. In addition, the loss distribution of the proposed converter in different powers is investigated. The proposed dual-transformer-based dual-active bridge converter is compared with the presented converters. Finally, the proposed converter with a low-voltage side (VL= 300 V), the switching frequency of power MOSFETs (fs= 50 kHz), and an accurate model of the electric battery at a high-voltage side (VH= 450 V) are simulated to verify the way of charging and discharging the electrical battery with the proposed converter under normal and open-circuit fault of transformers. [ABSTRACT FROM AUTHOR]

In this work, the impact of rare earth element samarium "Sm" substitution on Ba 4 Co 2 Sm x Fe 36-x O 60 U-type hexaferrites was studied in detail. Five compositions with step size x = 0.00, 0.025, 0.050, 0.075 and 0.1 were synthesized. These five series were prepared using the sol-gel auto-combustion method and the samples were sintered for 6 h at 1250 °C. The synthesized samples were characterized by XRD, FTIR, Raman Spectroscopy, X-ray photoelectron Spectroscopy and vector network analyzer (VNA). The structure crystallography of Ba 4 Co 2 Sm x Fe 36-x O 60 was examined via XRD. The impact of Sm3+ substitution was assessed across all lattice parameters. Lattice constants 'a' and 'c' were found between 5.886 and 5.881 Å and 113.179 to 113.037 Å, respectively. FTIR was used to learn more about the crystal structure and atomic vibrations between 400 and 1000 cm−1 wave number, where higher frequency bands appear at 570 cm−1 (tetrahedral site) and the lower frequency band occurred at 424 cm−1 due to the metal-oxygen stretching vibration (Fe-O) bond at the octahedral site. Each spectrum supported a U-type hexagonal structure i.e. an investigation of the chemical and intermolecular bonds via Raman spectra. XPS confirms the presence of elements in materials. Different dielectric parameters were observed in the 1 MHz to 6 GHz range of all prepared samples. Cole-Cole graphs of prepared materials highlighted the influence of grain boundaries. A solitary semicircle in the impedance of a specific section of grain boundaries was evidenced through Cole-Cole plots. Dielectric properties strongly depend on electron hopping between Fe2+ and Fe3+ ions. The optimized parameters suggest the utility of these materials in microwave devices, multilayer chip inductors and high-frequency electrical circuit applications to reduce skin effects. [ABSTRACT FROM AUTHOR]

This paper presents the design and application of a boost converter operated in continuous conduction mode for 15 W, with a 25 kHz switching frequency using an inductor-capacitor-inductor (LCL), pi, inductor capacitor (LC) with damping, and LC electromagnetic interference filters. Also, modeling and analysis of the boost converter in terms of state space and small signal are given. Furthermore, the effect of each filter on differential mode (DM) noise and control characteristics is presented using root locus and bode diagrams, which are not detailed in the literature for the boost converter. All results obtained from applications and simulations are compared. Moreover, frequency spectrums are given to compare DM noises. As a result, from a control point of view, the LCL filter provides better results, and for reducing DM noise, the LC and pi filters are superior to others. Besides, the LCL filter reduces the inductor value by 30% compared to other filters. [ABSTRACT FROM AUTHOR]

This research presents a new Finfet transistor that utilizes current mode active device technology to construct a floating and grounded inductance simulator. In this work, the grounded inductance circuit (GIC) uses only two Z-copy current follower transconductance amplifiers (Zc-CFTA's) and one grounded capacitor, and the floating inductance circuit (FIC) in the suggested simulator uses just three Z-copy current follower transconductance amplifiers (ZC-CFTA's) as active elements with only a single grounded capacitor as an active inductor simulation. The aim of this work is to realize an active inductance simulator with only one capacitor, which is commercially available as an active building block (ABB). In addition, the designed circuit shows low incremental active and passive hypersensitivity and non-interactive electronic control of the quality factor (Q) and natural angle frequency (w0). Through computer simulation results with a fourth-order Butterworth band-pass filer using LT-spice and a cadence virtuoso program with a 7nm process parameter, the suggested circuits' performances were assessed. [ABSTRACT FROM AUTHOR]

In this paper, several types of microstrip power divider are studied and compared in terms of harmonics suppression and size reductions. The importance of this research lies in the fact that power dividers are critical components in various communication systems, and their performance directly affects the overall system efficiency. The conventional structure of the power divider has an acceptable performance at operating frequency in terms of excellent output ports isolation, low insertion loss, and high return loss, but occupies large size and passes unwanted signals at higher frequencies along with desired signal without any suppression. Harmonics are popular distortion and has different distortion impacts in many different facilities. Recently, several techniques are introduced to overcome these drawbacks. Applied open stubs, applied resonators, lumped reactive components such as capacitors and inductors, coupled lines, defected ground structure (DGS), and electronic band gaps are common methods, which are widely used to overcome these drawbacks. Finally, the study results show that the resonatorbased power dividers and coupled-line-based power dividers have good performances in terms of size reduction and harmonic suppression but increase insertion loss parameter. Furthermore, the lumped reactive component-based power dividers and applied DGS and electromagnetic bandgap cells suppress unwanted harmonics, but they need extra process to fabrication, which is undesirable. Moreover, the open-stub-based power dividers have moderate performance with simple structure, but size reduction and harmonics suppression are not so superior in this method. Overall, the results of this study can be used to design power dividers for desirable applications with high performances. [ABSTRACT FROM AUTHOR]

Nitrogen fixation, production of NO and NO2 from N2 and O2 in air, has been investigated with transient spark self-pulsing DC discharges. NO production is boosted by the addition of capacitors and an inductor to the electrical circuit which drives the discharge. The quantity of NO produced per joule of electrical input energy is doubled, though the quantity of NO2 produced drops. The yield of NO is also increased because the modified circuit enables higher discharge currents to be used. NO concentrations as high as 2000 ppm were obtained with input energy densities of around 300 J per liter of input gas, whilst NO2 concentrations were around 150 ppm. This simple modification of the driving circuit may have potential for optimizing the plasma chemistry with other input gas mixtures and for scaling up nitrogen fixation from air. [ABSTRACT FROM AUTHOR]

The present work proposes a nonlinear model of a buck–boost DC-DC power converter considering the nonlinear magnetic characteristics of the power inductor and electrical losses of the system. The Euler–Lagrange formalism is used for formulating the proposed model. Previous research works have reported mathematical models to describe power inductor dynamics. However, a gap in the literature remains regarding modeling this kind of element when it operates within power converters. Also, a linear-based controller scheme is proposed to regulate a non-ideal buck–boost DC-DC power converter. A methodology for tuning the proposed controller is presented, which considers the nonlinear model structure of the power converter, the linearization procedure based on an identification process, and a frequency domain analysis based on the approximated linear model. Finally, the tuned control scheme is tested on the nonlinear model of the power converter under several operational conditions showing excellent performance by effectively regulating the output voltage. The results are compared with those derived from alternative control strategies, and a better performance is generally obtained. [ABSTRACT FROM AUTHOR]

The object of research is the force effect of a circular magnetic field of cylindrical inductors with alternating current windings on the actuator element of technological reactors – a ferromagnetic particle. Technologies using a rotating magnetic field and ferromagnetic particles (RMF and FP) are increasingly used in industry, in devices for fine and ultra-fine grinding, mixing and activation, in the construction and chemical industries, in energysaving and environmental systems. In previous studies, the authors proposed a method for calculating the force effect on ferromagnetic particles (FP) of an elliptical rotating magnetic field (RMF) of an external cylindrical inductor with a symmetrical alternating current winding. In this work, based on this technique, formulas for the force effect on the FP of the fundamental harmonic of RMF of cylindrical inductors with different numbers of pole pairs are derived and analyzed. It is shown that for a hard magnetic and saturated magnetically soft (soft-magnetic) particle in a circular field of a cylindrical inductor with the number of pole pairs greater than one, the magnitude of the magnetic displacement force does not depend on the orientation of the magnetic moment of the ferromagnetic particle, and the direction of action of this force is determined by the angle between the circular field induction vector and the magnetic moment of the particle. While maintaining the similarity of the inductors and the equality of the amplitude of the magnetic induction on the surface of the inductor bore, the magnetic displacement force does not retain the similarity, in particular, while maintaining the values of the magnetic moment of the particle, this force is inversely proportional to the radius of the bore of the cylindrical inductor. Examples are given of the use of formulas for calculating the ratio of displacement forces to the weight of a particle and the calculation of forces for an unsaturated soft-magnetic particle, where, due to the dependence of the magnetic moment on the field strength, the calculation formulas are modified and take on a slightly different form than the formulas for a particle with a constant modulus magnetic moment. The research results will be useful for engineers and researchers involved in the research, development, design and operation of reactors with RMF and FP technologies. [ABSTRACT FROM AUTHOR]

A bidirectional converter (BDC) designed with high voltage gain and it is incorporated with the soft-switching operations to the insulated gate bipolar transistors (IGBTs). The main dual operating characteristics of this converter are boost and buck modes respectively. In order to achieve the reduced switching losses and improved efficiency, the main IGBTs are operated at zero-current (ZC) while the IGBTs commutating from turn-on to turn-off state. The ZC turn-off operation is obtained with the aid of soft-switched cell, which consists of resonant inductor (Lr), capacitor and additional IGBTs. In this work, the design simulation analysis for high-gain BDC was performed by 70/300 V power system with the maximum 800 W output power under the operating frequency of 50 kHz. The efficiency for the high-gain soft-switched BDC was obtained as 96.5% when it is operating in boost mode and efficiency of 97% was achieved for the buck mode operation. The simulation evaluations of the above said converters were performed by using MATLAB/Simulink. [ABSTRACT FROM AUTHOR]

The paper presents a synthesis of the author contributions in developing a new class of DC-DC hybrid converters (HDC) with large voltage conversion ratio. The HDC structures are obtained by introducing commutated inductive and capacitive cells in the classical DC-DC converters. With these topologies, the voltage conversion ratio is larger, at the same duty cycle, compared with the classical converters. The paper presents some of the developed configurations, with unidirectional and bidirectional power flow, and some corresponding applications in renewable energy conversion and automotive industries. [ABSTRACT FROM AUTHOR]

This paper presents a new modified voltage differencing voltage transconductance amplifier (MVDVTA) based meminductor emulator circuit. The proposed emulator circuit is memristor-less, uses only a single active building block (ABB) and has simple circuitry. The MVDVTA based emulator design consists of only two capacitors and a single resistor. The performance of the proposed design has been verified over a wide frequency span. For simulation purpose LTSpice tool is used with 0.18µm CMOS technology. The proposed emulator has also been employed in chaotic oscillator and adaptive learning application circuit to verify its workability. The proposed design gives satisfactory performance for both the applications, hence confirming its functionality in practical environment. [ABSTRACT FROM AUTHOR]

Copyright of Informacije MIDEM: Journal of Microelectronics, Electronic Components & Materials is the property of MIDEM Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We apply probability theory for the analysis of the exponentially decaying transient response of a resistor inductor electric circuit with partially known value of the inductance due to its failure. The inductance is known to be within a continuous interval, and the exact value is unknown, which may happen as a result of inductor faults due to a variety of factors—for example, when the circuit is deployed in an unusually harsh environment. We consider the inductance as a continuous uniform random variable for our analysis, and the transient voltage is treated as a derived random variable which is a function of the inductance random variable. Using this approach, a probability model of the transient voltage at the output terminals of the circuit is derived in terms of its cumulative distribution function and the probability density function. In our work, we further elaborate that the probability model of any other circuit parameter can also be obtained in a similar manner, or it can be derived from the transient voltage probability model. This is demonstrated by getting the model of a branch current from the probability distribution of the transient voltage. Usage of the probability model is demonstrated with the help of examples. The probability of the transient voltage falling in a certain interval at a given instant of time is evaluated. Similarly, the probability values of the branch current in different intervals are determined and analyzed. The derived probability model is checked for its validity and correctness as well. The model is found to be useful for probabilistic analysis of the circuit. [ABSTRACT FROM AUTHOR]

This work focuses on the possibility of using a tuned inductor in electric power systems with adaptive features. The presented idea of inductor operation, using an interaction of the magnetic fluxes, is a new approach to designing such devices. Examples of power adaptive systems are devices for improving the quality of electricity. Therefore, various types of 'compensators' of reactive power (or both reactive and distortion power) are used in electrical systems as a preventive measure. The tuned inductor, presented in this work, offers wider possibilities for power compensation in electric systems, compared to the classic solutions of compensators based on fixed inductors. Another possible implementation of such an inductor solution is in static power electronic devices, installed in AC transmission grids to increase power transfer capability, stability, and controllability, through a series and/or shunt compensation. Nevertheless, the use of the proposed device in the aforementioned electric systems is only one example of the possible implementations in the power electronics area. In this work, the following issues are presented: exemplary solutions of compensators with the adaptive features, rules of the tuned inductor operation, test results of the 3D field model of the inductor, and test results of the laboratory model of the electric system with this device. [ABSTRACT FROM AUTHOR]

Additive manufacturing technology is being used to process microspiral inductors. In this work, we applied stereolithography to print a microspiral inductor mold and fabricated microspiral inductors with 2.5, 4.5, and 6.5 turns by injecting eutectic gallium indium (EGaIn), which is a liquid metal. Based on a reconstruction model (obtained by reconstructing micro-computed tomography data), an algorithm was established for a nondestructive measurement of the structural parameters of the inductors. The electrical performance of the inductors was tested by conducting physical experiments and then characterized by simulating the reconstructed model. The measurement results of the structural parameters showed that the processing error of the wire diameter could be controlled within 20%; the machining error of the other structural parameters could be well controlled within 5%, with a high molding accuracy. Compared to the theoretical model results, the simulation results based on the reconstructed model showed improvement in the accuracy of the inductance values by 20.5, 16.8, and 7.6%, the accuracy of the Q factor by 13.2, 20.7, and 19.5%, and the accuracy of the self-resonant frequencies by 9.3, 6.31, and 8%, respectively. [ABSTRACT FROM AUTHOR]

In order to develop a portable flash x-ray source, a compact explosive pulsed power source based on an explosive-driven ferroelectric generator (EDFEG) is investigated numerically and experimentally in this paper. The EDFEG is used as a primary power supply to charge a pulse capacitor, and then the capacitor outputs high current through an inductor and an electrical exploding opening switch (EEOS). Finally, a high voltage fast pulse is generated on a diode, which generates x rays. A circuit model was built to analyze the performance of this compact pulsed power source. A portable flash x-ray generator prototype was constructed in our laboratory. The typical experimental results illustrated that after metal wires of the EEOS exploded, a high-voltage fast pulse with a peak value of 180 kV, a rise time of 2.8 ns, and a pulse width of 30 ns was generated on the x-ray diode. Meanwhile, an x-ray pulse with a pulse width of 19 ns, a focus of about 1 mm, and a dose of 100 mR at 15 cm was obtained. [ABSTRACT FROM AUTHOR]

This work focuses on the concept of operation and possibility of using a tuned inductor in electrical power systems with adaptive features. The idea presented here for the operation of the inductor is a new approach to the design of such devices. An example of a power adaptive system is a device for improving the quality of electricity. The negative impact of nonlinear loads on the operation of a power grid is a well-documented phenomenon. Hence, various types of "compensators" for reactive power, or for both reactive and distortion power, are used in electrical systems as a preventive measure. The concept of an inductor presented here offers wider possibilities for power compensation in power supply systems, compared to traditional solutions involving compensators based on fixed inductors. The use of the proposed solution in an adaptive compensator is only one example of its possible implementation in the area of power devices. In this work, we discuss the structure of the compensator, the basic aspects of the operation of the inductor, the results of simulation studies and the results of measurements obtained from a prototype. [ABSTRACT FROM AUTHOR]

To overcome the low output voltage of Renewable Energy Sources (RESs) such as photovoltaic arrays (PVAs) and fuel cells, a new multi-input DC/DC converter is presented in this paper. This converter is based on a combination of modified quadratic buck-boost converters, Switched Inductors (SIs), and Voltage Multiplier Modules (VMMs). The high voltage gain can be achieved by adjusting the duty cycle and turn ratio of the coupled inductor of VMM. This structure inherits all the advantages of the SEPIC converter and using a bidirectional input port (in which an Energy Storage System (ESS) can be connected) and several unidirectional input ports. The load power can be flexibly divided among various power sources. Due to the buck-boost characteristics of the presented converter, it is suitable to charge-discharge the ESS. A Coupled Inductor (CI) is used to couple energy from input to the output equipped with the VMM. Moreover, the use of SI reduces the rise time and ripple of the input current. The stability of the proposed converter against momentary changes of VPV and Ro is the main advantage of this converter. Moreover, considering a secondary ESS as Vi instead of PV allows the converter to be active 24 hours a day. In this converter, the use of two ESSs guarantees the supply of the required output power. In addition, two bidirectional input ports prepare the ESSs charging and discharging capabilities. To verify the analysis and feasibilities of the proposed converter, simulation results are presented [ABSTRACT FROM AUTHOR]

Introduction. The article is devoted to the development of the microprocessor automatic control system for a gearless controlled electric drive of a mono-switch tie based on a linear inductor electric motor. This solution provides control the position of the switch point, to carry out the transfer process with a smooth drive of shanks to the frame rail, to protect electric motor elements from overloads. Goal. Development and study of the behavior of microprocessor automatic control system for mono-switch tie type with linear inductive electric motor and discrete PID speed controller which coefficients are adjusted according to Chien-Hrones-Reswick method to meet modern traffic safety requirements and improve operational reliability factors. Methodology. On the basis of electric drive theory, a kinematic line of a mono-switch tie type with nonlinear friction characteristic is presented. Using differential equation theory and Laplace transformation, a mathematic description of a linear inductor electric motor has been made. Using the z-transform method, a difference equation for describing a discrete PID speed controller is obtained, the coefficients of which are derived using the Chien-Hrones-Reswick method. A simulation mathematical model of the electric drive mono-switch tie type as the microprocessor automatic control system with linear inductive electric motor and discrete PID speed controller and nonlinear friction characteristic was built in MATLAB. Results. Simulation modelling of a mathematical model of the microprocessor automatic control system of the electric drive mono-switch tie type with the linear inductive electric motor and discrete PID speed controller and nonlinear friction characteristic have been developed and performed. Studies of dynamics of switch point movement have shown that, a drive time of less than 0.7 s at a constant speed motor armature of 0.2 and 0.3 m/s provides to meet modern requirements for railway switch points. The application of discrete PID speed controller has shown improved dynamics of switch point. Originality. First for the electric drive of the mono-switch tie type with linear inductive electric motor a mathematical model of the discrete PID speed controller and nonlinear friction characteristic as an object of speed control of switch point movement, has been developed. Practical value. Mathematical model of a railway track switch of the mono-switch tie type with linear inductive electric motor and discrete PID speed controller has been developed to carry out the control of the position of the switch point, process with a smooth drive them to the frame rail, to protect electric motor elements from overloads. [ABSTRACT FROM AUTHOR]

Copyright of Latin-American Journal of Physics Education is the property of Latin-American Physics Education Network and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A FDNR (Frequency Dependent Negative Resistance) simulator has been presented, which uses single Voltage Differencing Current Conveyor (VDCC) along with two grounded capacitances to realize the pure FDNR function. The proposed FDNR simulator places itself as one of the most compact circuit architecture present in the available literature. It is a resistor-less realization and finds no requirement of any active/passive component/parameter matching to realize the FDNR behaviour. The presented analysis shows that the proposed circuit remains always stable under the effect of parasitics irrespective of any values of circuit parameters, which is not witnessed in many previously reported FDNRs. The usability of realized synthetic FDNR has been checked through validation of developed higher-order CDR filters by using the proposed FDNR. To verify the designed circuits, the presented configurations have been simulated under the PSPICE simulation environment. The experimental results are shown for the commercial ICs (AD844 and CA3080) based physical realization of described FDNR. [ABSTRACT FROM AUTHOR]

In the electrical engineering field, there are two types of system which can potentially generate resonance under excitation, one is the electrical system with inductor and capacitor, the other is the mechanical system with spring-mass characteristic. A lot of research on active damping control algorithms for grid-connected inverters with LCL filter and inverter-driven machine with multirotating masses have been demonstrated. However, research works for these two systems were carried out independently and there is a lack of systematic comparison for modelling and control between these two systems. This article will unify the mathematical models and active damping control algorithms for these two systems. It is found that the mathematical models and control structures are fundamentally the same. The existing or future potential active damping control algorithms used in electrical system can be applied in mechanical system and vice versa to avoid reinventing the wheel. Parameter sensitivity analysis for controller and feedback gains was performed for electrical systems in the discrete z-domain. For mechanical systems, it is found that a substantial electromagnetic torque overshoot was introduced when applying the active damping control and it was analyzed quantitatively with various damping coefficients to guide the inverter design. Finally, experimental tests were done to verify the findings. [ABSTRACT FROM AUTHOR]

• Design shielding devices to reduce the impact on other electrical equipment and protect the health of researchers. • Use simulation analysis to design shielding devices and conduct simulation tests. • The shielding device weakens the magnetic induction intensity and meets the standard requirements. • Use variance analysis to design the shielding device to achieve lightweight design. • Make a shielding device and conduct on-site tests to verify the shielding effect. The quench protection system is the most important safety equipment of the Comprehensive Research Facility for Fusion Technology (CRAFT) project, which is used to protect asset security in the event of superconducting device quenching. Since the pulse inductor of the quench protection system works under extreme conditions, a strong induced magnetic field will be generated around the equipment, which will affect the normal operation of other electrical equipment in the inductor cabinet. Aiming at this situation, it is necessary to analyze the changing magnetic field of the inductor. This paper proposed a new shielding structure that can effectively reduce the magnetic induction around the inductor, and the effectiveness of the design was verified through simulation. [ABSTRACT FROM AUTHOR]

In this study, a new simulated grounded inductor (SGI) is developed. It has a simple structure because it employs two-terminal active devices (TTADs). Moreover, it has a minimum number of passive elements, considering the TTAD-based configurations. However, there is a single passive element-matching constraint for two resistors. Derived from the developed SGI, a second-order voltage-mode universal filter application is given. With proper connection of inputs, it yields band-pass (BP), high-pass (HP), low-pass (LP), all-pass (AP), and notch filter (NF) responses. The performance of the developed circuits is verified through the SPICE simulation program. Additionally, an experimental test result is given for the developed SGI. [ABSTRACT FROM AUTHOR]

This paper presents the circuit of a low-noise amplifier (LNA) using active inductor (AI) input matching with common gate (CG) current-reused technique. This configuration is implemented in 90 nm CMOS and enables to achieve high power-gain (S21) with ultra-wideband (UWB) input matching at low power levels. Utilization of modified high-Q AI at the input side of the proposed LNA reduces the number of inductors and achieves UWB from only two inductors. Proposed LNA dissipates 10.4 mW from 1.0 V supply and exhibits an S21 response of 18.0 ± 0.8 dB for 3.1–10.6 GHz with a maximum and average S21 of 18.8 dB and 18.22 dB, respectively. The proposed LNA has noise-figure (NF) equal to 3.36–4.68 dB, with input (S11) and output (S22) reflection coefficients of less than −9.3 dB and −11.35 dB, respectively across the entire UWB range. [ABSTRACT FROM AUTHOR]

A simple method is proposed here to improve the gap loss concentration problem of a nanocrystalline core in an LCL filter inductor for high switching frequency converters using SiC devices. This alloy‐gapped inductor design aims to reach two primary goals. First, to reduce the concentrated gap loss in a nanocrystalline core. Second, decrease the maximum temperature around the gap region and lead to more even temperature distribution. A finite element (FE) power loss and thermal models, validated by experiment, have been created to evaluate the proposed design. Based on the FE model results, the eddy current loss on the surfaces, which used to have the most severe gap loss is reduced by either 70% or 40% for the two commonly used winding placements. The total eddy current loss can be reduced by 29% and 27% for those two winding placements. In addition, FEA thermal model indicates that the hotspot temperature can be significantly decreased, and the nanocrystalline core can achieve a more uniform temperature distribution by this design, which can be a potential downsize method for the nanocrystalline core inductor. [ABSTRACT FROM AUTHOR]

A new isolated zero‐voltage switching (ZVS)/zero‐current switching (ZCS) push–pull (PP) DC/DC converter is presented. One auxiliary switch S3 and a clamping capacitor Cc are introduced at the primary of the conventional push–pull converter and a voltage doubler‐rectifier is adopted on the secondary side. This proposed converter has the features: (1) Switching losses are reduced significantly owing to zero‐voltage switching of primary switches and zero‐current switching of secondary diodes over a wide load range variation. (2) The voltage spike across all of the power devices can be clamped that enable the use of low‐voltage, low‐performance, and lower‐cost devices. (3) The energy stored in the transformer leakage inductance is used for the soft‐switching action and no additional resonant inductor is required. (4) A voltage doubler‐rectifier is employed to remove the problem of the diode reverse‐recovery effect and reduce the duty cycle loss that provides a much higher voltage conversion ratio. These merits make this simple converter provide an attractive solution for a distributed power system, uninterruptible power system, or battery charge/discharge system. The detailed operation, analysis, design, comparative study, and experimental results for the proposed converter are presented and a 600 W prototype was developed to verify the discussed theoretical analysis. [ABSTRACT FROM AUTHOR]

This article presents the modeling and development of a DC-DC converter with Partial Swarm Optimization with Distinctive Feed Forward Propagation (PSO-DFFP) controller for hybrid power systems, including photovoltaic panels. The transient and dynamic analysis of the proposed controller has been presented. The PSO-DFFP controller has been designed to improve the operating efficiency and reduces the input converter current ripple. The ANFIS and PSO DFFP controllers are developed, and the performance of the system is compared. The proposed system reduces the switching losses and voltage drops in switching modes. The proposed system is demonstrated and developed with a 200W, 100kHz model. From the experimental results, it can be exposed that the proposed system is acceptable for PV applications. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) are widely used in electric vehicles (EVs) due to their superior power performance over other batteries. However, when connected in series, overcharged cells of LIBs face the risk of explosion, and undercharged cells decrease the life cycle of the battery. Eventually, the inconsistency phenomenon between cells resulting from manufacturing tolerance and usage process reduces the overall charging capacity of the battery and increases the risk of explosion after long-time use. Research has focused on synthesizing active material to achieve higher energy density and extended life cycle for LIBs while neglecting a comparative analysis of equalization technology on the performance of battery packs. In this paper, a nondissipative equalization structure is proposed to reconcile the inconsistency of series-connected LIB cells. In this structure, a circuit uses high-level equalization units to enable direct energy transfer between any two individual cells, and dual interleaved inductors in each equalization unit increase the equalization speed of a single cell in one equalization cycle by a factor of two. The circuit is compared with the classical inductor equalization circuit (CIEC), dual interleaved equalization circuit (DIEC), and parallel architecture equalization circuit (PAEC) in the states of standing, charging, and discharging, respectively, to validate the advantages of the proposed scheme. Considering the diversity of imbalance states, the state of charge (SOC) and terminal voltage are both chosen as the equalization criterion. The second-order RC model of the LIB and the adaptive unscented Kalman filter (AUKF) algorithm are employed for SOC estimation. For effective equalization, the adaptive fuzzy neural network (AFNN) is utilized to further reduce energy consumption and equalization time. The experiment results show that the AFNN algorithm reduces the total equalization time by approximately 37.4% and improves equalization efficiency by about 4.89% in contrast with the conventional mean-difference algorithm. Particularly, the experiment results of the equalization circuit verification certify that the proposed equalization structure can greatly accelerate the equalization progress and reduce the equalization loss compared to the other three equalization circuits. [ABSTRACT FROM AUTHOR]

The switched‐capacitor DC‐DC converters have been widely applied to convert energy from low voltage to DC bus for the power generation systems with fuel cells, photovoltaic array, and so on. However, the large capacitance is generally selected to eliminate the high current spike of switched‐capacitors in the hard‐switching switched‐capacitor (SC) DC‐DC converters, which will lead to the large volume and weight of capacitors and of converters. To solve this problem, a non‐resonant soft‐switching (NRSS) technique with linear current on switching cycle time‐scale for switched‐capacitor DC‐DC converters is first proposed in this paper, which achieves zero‐current‐switching (ZCS) turn‐on of switches and ZCS turn‐off of diodes with linear current on switching cycle time‐scale. In detail, the NRSS technique is proposed based on the idea that the current of an auxiliary inductor on switching cycle time‐scale is considered as the linear parts for the resonant current of the auxiliary inductor on resonant cycle time‐scale. The proposed NRSS technique is utilized into SC DC‐DC converter and the current spikes of switches can be reduced to two third by using the same capacitance compared with the hard‐switching SC DC‐DC converters and be reduced to a third compared with the resonant soft‐switching SC DC‐DC converters. Further, nine new soft‐switching SC DC‐DC converters, with single switch and double switches, are built based on the proposed non‐resonant soft‐switching technique. Finally, the non‐resonant soft‐switching technique is verified theoretically and experimentally by three of the nine proposed SC DC‐DC converters. This paper provides a new way to realize soft‐switching during the non‐resonant interval on switching cycle time‐scale and a new method to significantly reduce the required capacitance in SC DC‐DC converters. [ABSTRACT FROM AUTHOR]

This study proposes a high step‐down DC‐DC converter with minimum elements. In the proposed converter, soft switching condition is provided with only one auxiliary switch, which simplifies the structure of the converter. Leakage inductor energy is used to create a zero voltage condition; so the mutations created by this inductor are neutralised. The control of the auxiliary switch is complementary to the main switch, which does not require a new and complex control circuit. Due to low voltage gain, the proposed converter is suitable for use in voltage regulator modules. The proposed converter is completely analysed. To confirm the theoretical analysis, an experimental sample is made and tested at 15 W and the results are presented. Also, the efficiency of the proposed converter at full load is 97.5%. [ABSTRACT FROM AUTHOR]

Copyright of Informacije MIDEM: Journal of Microelectronics, Electronic Components & Materials is the property of MIDEM Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Informacije MIDEM: Journal of Microelectronics, Electronic Components & Materials is the property of MIDEM Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In applications where DC current is superimposed, such as inductors for non‐isolated DC‐DC converters, powder core can be considered as an attractive solution owing to its superior features such as: high saturation flux density, high Curie temperature, and soft‐saturation property. However, in powder cores, a drop of inductance appears prominently due to DC superimposition characteristics. This feature is not a desirable characteristic because it leads to an increase in the inductor ripple current under heavy load, which complicates the thermal design of power semiconductors and capacitors. This paper verifies the improvement of DC superimposition characteristics of powder cores by applying coupled inductors. First, the effect of coupled inductors on the improvement of DC superimposition characteristics is experimentally verified. Second, a measurement method for the DC superimposition characteristics of coupled inductor is proposed. Then, a magnetic circuit model is built using the measurement results. Finally, a coupled analysis of magnetic and electric circuits is performed, and it is confirmed that lower magnetic field operation can be realized by coupled inductors even under heavy load conditions. It has been proven that coupled inductors are effective in improving the DC superposition characteristics of the powder cores. [ABSTRACT FROM AUTHOR]

This paper proposes a high step‐up interleaved boost‐Cuk converter with integrated magnetic coupled inductor that is suitable for photovoltaic systems. By connecting the boost converter and the Cuk converter in parallel at the input terminal and the output terminal in series and integrating a coupled inductor voltage multiplier cell, the proposed converter achieves a higher voltage gain while retaining the continuous input and output current characteristics of the Cuk converter. The passive clamping branch is used to absorb the leakage inductance energy, which effectively suppresses the voltage spike generated by the switch parasitic capacitance and leakage inductance resonance and reduces the maximum voltage stress of the switch. The operation principle of the converter is analysed and the magnetic integration equivalent model and design criteria of the two coupled inductors are given. An array magnetic integrated structure is designed, which effectively reduces the DC bias inside the magnetic core. Finally, a 380 W experimental prototype is built to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

This article proposes a current step‐up converter for high‐gain applications by combining a buck‐boost converter and a Cuk converter to form a buck‐boost‐Cuk converter with a shared input terminal. In order to further improve the performance of the converter and reduce the number of components, the primary side and secondary side of the coupled inductor are respectively connected to different branches, so that the diode‐capacitor branch in this structure could be used as a voltage doubler branch, and performed as a passive clamp circuit to absorb leakage inductance energy, which suppressed the voltage spike generated by the parasitic capacitance and the leakage inductance of the resonance; to some extent, it reduced the voltage stress of the power switch. This paper analyzed the operating principle and performance of the converter, then made the parameter design for the proposed converter, and compared the performance of different converter systems. At last, this paper built a 150 W experimental prototype to verify the correctness of the theoretical analysis. [ABSTRACT FROM AUTHOR]

Percolative composites with negative permittivity have attracted widespread attentions due to their great potential in electromagnetic shielding and microwave devices. Targeting at achieving epsilon-negative properties, the percolative graphite/barium titanate (GR/BaTiO 3) composite is herein designed and prepared using hot-pressing sintered process. It's found that the plasma oscillations of delocalized electrons result in the epsilon negative permittivity behaviors when the GR contents exceeds the 2 wt% (percolation threshold), and frequency dependence of the negative permittivity which is in well agreement with the Drude model. Meanwhile, it's demonstrated that the ac conductivity represents a typical metal-like behavior as the conductive networks formed within the composites by the increasing GR loadings. Moreover, the equivalent circuit analysis reveals the relationships between capacitive-inductive transition and the conversion of permittivity changing from positive to negative. This work provides effective possibility for developing excellent dielectric properties of percolative GR/BaTiO 3 composite for capacitors and coil-less electrical inductors applications. [ABSTRACT FROM AUTHOR]

To find the optimal magnetic components designing process within the dimensional limitation, different inductor arrangements are developed. Different combinations of air‐gaps and material arrangements are used within the limited bobbin space to improve the saturation current capacity within the already set dimension. In this study, the mechanism requirement set at 1U height is the limitation. There are two center‐pole material cores, and air‐gap distribution arrangement in the magnetic components. The saturation current value, magnetic flux density, flux fringing, and power loss of inductors are investigated with simulation, equation calculation and actual circuit measurement. The magnetic distribution affects the inductor performance because of the different relative permeability values, skin effect, proximity effect, and fringing effect. This research uses equations to find the magnetic flux density and the fringing magnetic flux, and uses Comsol Multiphysics® software to simulate the magnetic field. A 500 W boost power factor corrections (PFC) converter topology is used as an example experiment to compare and verify the inductors selected with proposed design methodology. Finally, the most appropriate core is chosen to implement the two‐stage AC/DC power supply products to improve the power supply performance. [ABSTRACT FROM AUTHOR]

This study proposes a new interleaved high step‐up topology based on cross‐coupled inductors and voltage multiplier cells (VMCs). Two series capacitors in VMC are employed to raise voltage gain and diminish peak voltage across switches. Thus, low voltage MOSFETs with low on‐resistance (Rds(on)) can be used in the proposed converter. Due to the presence of the leakage inductors in coupled inductors, the falling rate of the output diodes current is controlled and the diode recovery current problem at turn‐off can be mitigated. In addition, switches are turned on under ZCS conditions which results in efficiency improvement. Using two‐phase topology reduces input current ripple and shares power losses between each phase. The converter is analyzed and its operation is investigated using detailed comparisons. Finally, to confirm the performance of the proposed converter, a 30 V input voltage to 400 V output voltage prototype with the rated power of 220 W is implemented and tested in the laboratory. [ABSTRACT FROM AUTHOR]

Memristors are passive non‐linear circuit components with memory characteristics, and have been recognized as the fourth basic circuit component, along with resistors, capacitors, and inductors. It has been nearly half a century since the conceptualisation of the memristor, and related research has mainly focussed on the two aspects of binary and continuous memristors. However, compared with these two types of memristors, tri‐state and multi‐state memristors have greater data density per device, with rich dynamics and great potential in logic and chaotic circuit applications. Moreover, previous studies show that the series‐parallel connection of memristor generates more diverse circuit behaviours and increased capacity over a single memristor. However, most of this research is based on mathematical analysis, and lack behavioural circuit simulations or experimental validation. Here, the tri‐state memristor is proposed and the mathematic and equivalent Spice models of the tri‐state memristor is shown. Furthermore, the circuit characteristics are studied with a complete characterisation of its series‐parallel behaviours of the tri‐state memristor. Simulations are performed with LTSpice, and the results verify the theoretical analysis, which provides a strong experimental basis for the study of combinational memristive circuits. [ABSTRACT FROM AUTHOR]