Ladder Circuit Research Articles

Electric Circuit Analogs of First-Order Dual-Phase-Lag Diffusion

Abstract The dual-phase-lag (DPL) model of non-classical diffusion plays an expanding role for applications involving transient heat, mass, and momentum transfer. To open a new realm of applications for the model, the work reported here introduces RLC-type (resistor-inductor-capacitor) and RCC-type (resistor-capacitor-capacitor) electric circuits that behave as discrete analogs of first-order, continuum DPL diffusion. Importantly, the phase lags are two time-scales representing departures from classical diffusion that define the wave-like and over-diffusive regimes of DPL behavior. Expressions for these phase lags arise while deriving the difference-differential equations that govern the circuits. Furthermore, simulations exhibit DPL behavior for simple, one-dimensional ladder circuits subjected to step increases in boundary voltages. In particular, the subsequent voltage disturbances in the circuits propagate faster in the over-diffusive regime than in the wave-like regime. The simulations also show that DPL behavior stems from transient divisions of current between RL components in the wave-like circuit and between RC components in the over-diffusive circuit. Consequently, adopting the DPL perspective in the design of electronic systems may inspire novel applications that take advantage of DPL behavior. Finally, the circuits introduced here may lead to the study of DPL diffusion in analogous scenarios of heat, mass, and momentum transfer that are difficult to access experimentally.

Enhanced Spectroscopic Insight into Acceptor-Modified Barium Strontium Titanate Thin Films Deposited via the Sol-Gel Method.

In the present paper, composite thin films of barium strontium titanate (BaxSr1-xTiO3) with an acceptor modifier (magnesium oxide-MgO) were deposited on metal substrates (stainless steel type) using the sol-gel method. The composite thin films feature BaxSr1-xTiO3 ferroelectric solid solution as the matrix and MgO linear dielectric as the reinforcement, with MgO concentrations ranging from 1 to 5 mol%. Following thermal treatment at 650 °C, the films were analyzed for their impedance response. Experimental impedance spectra were modeled using the Kohlrausch-Williams-Watts function, revealing stretching parameters (β) in the range of approximately 0.78 to 0.89 and 0.56 to 0.90 for impedance and electric modulus formalisms, respectively. Notably, films modified with 3 mol% MgO exhibited the least stretched relaxation function. Employing the electric equivalent circuit method for data analysis, the "circle fit" analysis demonstrated an increase in capacitance from 2.97 × 10-12 F to 5.78 × 10-10 F with the incorporation of 3 mol% MgO into BST-based thin films. Further analysis based on Voigt, Maxwell, and ladder circuits revealed trends in resistance and capacitance components with varying MgO contents, suggesting non-Debye-type relaxation phenomena across all tested samples.

Analysis of Fractional Electrical Circuit Containing Two RC Ladder Elements of Different Fractional Orders

Abstract The study addresses the topic of different fractional orders in the context of simulation as well as experiments using real electrical elements of fractional-order circuit. In studying the two solutions of the resistance-capacitance (RC) ladder circuit of appropriate parameters, different fractional orders of the electrical circuit are considered. Two fractional-order (non-integer) elements were designed based on the Continued Fraction Expansion (CFE) approximation method. The CFE method itself was modified to allow free choice of centre pulsation. It was also proposed that when making individual ladder circuits, in the absence of elements with the parameters specified by the program, they should be obtained by connecting commercially available elements in series or parallel. Finally, the theoretical analysis of such a circuit is presented using state-space method and verified experimentally.

Повышение адекватности моделей электромеханотронных систем

Development of electromechanotronic systems is connected with modeling and calculation of processes of various kinds. Electromagnetic, mechanical and thermal processes are analyzed, control, regulation, protection, monitoring and diagnostics problems are solved. Systems may contain a large number of power semiconductor elements. Short-term and multi-hour processes are calculated. Taking into account mutual connections of processes of various kinds in calculations of complex systems requires inadmissibly large expenditures of machine time. The problems are solved under more or less significant assumptions, which leads to a decrease in the adequacy of the results. The methods of systems calculation are proposed, which allow to reduce machine time consumption and to use more detailed description of installations and more accurate computer models. Possibilities of calculation of processes by «smooth components» of variables, and also application of dual models, in which speed and accuracy are combined, are considered. As an example, a system with an active cascade frequency converter containing 780 transistors and diodes, parasitic inductances and snubber circuits, and a vector-controlled induction motor with ladder circuits accounting for current displacement is analyzed. The model takes into account energy losses in the converter and in the motor, as well as the distribution of losses by components. It also takes into account emergency operation modes associated with disconnection of a part of low-voltage units of the cascade converter and maintenance of power quality at its input and output by symmetrization of the main current components and suppression of parasitic components.

A new AC motor driven by travelling magnetic field excited on LC ladder circuit without its nonlinearity

In three-phase AC motors, three-phase AC voltage system is essential to generate a rotating magnetic field. Three- phase AC motors also require a three-phase inverter for variable speed and torque operation. In general, the number of switching devices used in three-phase inverter is not less than six and decreasing its number is difficult. This paper focuses on an LC ladder circuit consisting of linear inductors and capacitors. This paper presents a new operating method of the AC motor based on a propagating magnetic field. It is successfully excited by connecting one single-phase AC power supply to the end of the LC ladder circuit. The induction motor operated by the presented method produces torque as in general induction motors.

L-2L ladder digital-to-analogue converter for dynamics generation of chemical concentrations.

Cellular response to dynamic chemical stimulation encodes rich information about the underlying reaction pathways and their kinetics. Microfluidic chemical stimulators play a key role in generating dynamic concentration waveforms by mixing several aqueous solutions. In this article, we propose a multi-layer microfluidic chemical stimulator capable of modulating chemical concentrations by a simple binary logic based on the electronic-hydraulic analogy of electronic R-2R ladder circuits. The proposed device, which we call L-2L ladder digital-to-analogue converter (DAC), allows us to systematically modulate 2 n levels of concentrations from single sources of solution and solvent by a single operation of 2n membrane valves, which contrasts with existing devices that require complex channel geometry with multiple input sources and valve operations. We fabricated the L-2L ladder DAC with n = 3 bit resolution and verified the concept by comparing the generated waveforms with computational simulations. The response time of the proposed DAC was within the order of seconds because of its simple operation logic of membrane valves. Furthermore, detailed analysis of the waveforms revealed that the transient concentration can be systematically predicted by a simple addition of the transient waveforms of 2n = 6 base patterns, enabling facile optimization of the channel geometry to fine-tune the output waveforms.

Towards Unique Circuit Synthesis of Power Transformer Winding Using Gradient and Population Based Methods

The aim of the paper is to synthesize a nearly unique, physically realizable and mutually coupled ladder circuit representation of a two-winding transformer by identifying the most accurate and reliable optimization technique such that prior knowledge in selecting the initial guess and search space is avoided. To this end, magnitude and phase of the driving-point impedance function are captured by performing sweep frequency response analysis (SFRA). Then, two widely used population-based algorithms namely, particle swarm optimization (PSO) and artificial bee colony (ABC) and one gradient-based sequential quadratic programming (SQP) algorithm are implemented. Two case studies are considered namely, i) 15 MVA, 66/11.55 kV transformer and, ii) 111 kVA, 7.33/1.22 kV transformer. The performance of the aforementioned algorithms is compared using three evaluation parameters namely, repeatability, accuracy and reliability

Enhancement of Bandwidth of an Extended Interaction Klystron by Symmetric Loading

A novel technique was developed for broadbanding of the interaction structure of an extended interaction klystron (EIK) through symmetric loading of the top and bottom shorting cavities while maintaining the periodicity of the ladder circuit the same. A 3-D electromagnetic analysis was carried out on a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$W$ </tex-math></inline-formula> -band structure in order to demonstrate the efficacy of the loading in broadbanding. The loading is found to marginally reduce the ohmic quality factor and the characteristic impedance of the structure. Measurements were also carried out on frequency scaled-down structures at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$X$ </tex-math></inline-formula> -band for validating the simulation. Symmetric stagger tuning of the circuit is facilitated through this loading and particle-in-cell analysis shows an enhancement in the 3-dB hot-bandwidth of the EIK by around 400% in comparison to an unloaded device.

Design principles of digital-to-analog conversion in information transformation

The object of study is digital-to-analog converter (DAC). The meaning of DAC, their design and control of various types of switches, as well as some logic elements that can act as a switch, as well as the principles of DAC operation based on various series, microcircuits were considered. The resistance of a 4-bit DAC circuit was calculated and, accordingly, the change in the output voltage when applying the corresponding combined input voltage was studied, and a timing diagram was accordingly developed. Using 1-state and toggle physical switches, schematics are established and side effects are learned. Ladder circuit established using R–2R type dividers as voltage dividers. The object of the research is to find and learn the most technologically advantageous concept in order to provide good communication between all equipments by transferring information from digital to analog in the industrial field as well as in other areas where automation is used. One of the biggest challenges in this research is to determine the smallest binary values. Before the use of electronic logic elements such as counters, bistable physical switches were used to create a break or connect state in the circuit, which caused additional energy and time loss or abrasion because of large voltages occur across the switches. The biggest issue was that when manufacturing integrated digital-to-analog converters, producing the right resistors with very different values is really difficult. As a result of this research, it is seen that the use of physical switches is unnecessary as a demand of today's modern technology, and integrated microcircuits are good to replace them. The programming of digital-to-analog converters on programmable hardware devices such as Arduino and Raspberry Pi were mentioned. If to predict the near future, digital-to-analog transmission will be realized only by only using logic elements, and this will change both their energy efficiency and size for the better.

RL-Ladder Circuit Models for Eddy-Current Problems With Translational Movement

This article proposes an adaptive equivalent <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$RL$ </tex-math></inline-formula> -circuit model for eddy-current devices with a single electrical port (one terminal voltage and current) and translational movement. The device is first characterized by means of frequency-domain finite-element computations in the relevant frequency and position intervals, for subsequently fitting constant-coefficient <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$RL$ </tex-math></inline-formula> -ladder circuits of adjustable size (i.e., variable number of branches and loops). The accuracy of the ladder-circuit model is assessed in both the frequency and time domains. The time-varying position involves the force computation from the circuit and the coupling with the mechanical equation. By way of validation, we study the axisymmetric magnetic-levitation device of TEAM Workshop problem 28. Results exhibit good convergence to reference finite-element ones with increasing number of branches.

Transforming interconnected systems and ladder circuits into implicit 2D models

In this paper, we consider two classes of spatially interconnected systems (including ladder circuits) modelled as mixed discrete-continuous linear 2D systems. Within the algebraic analysis approach to linear systems theory, we prove that these systems can always be transformed into equivalent implicit Roesser models. Moreover we show that ladder circuits can also be transformed into equivalent implicit Fornasini-Marchesini models. An advantage of our results compared to previous ones obtained through the zero coprime system equivalence approach is that the dimension of the state vector of the equivalent Roesser (or Fornasini-Marchesini) models is significantly smaller.

LCラダー回路上で励起される回転磁界を利用した交流モータ駆動法の基礎検討

LCラダー回路上で励起される回転磁界を利用した交流モータ駆動法の基礎検討

Detection of band edge frequencies in symmetric/asymmetric dielectric loaded helix slow‐wave structures

AbstractThe significant contribution of this paper is to present a comprehensive analysis and design of π‐point and band edge frequencies of reported helix SWSs including not only a microwave but also millimeter‐wave operation frequencies considering the methods in available literature which are the Coupled Mode Analysis (CMA), the Exact Floquet Approach (EFA), and the Auxiliary Functions of Generalized Scattering Matrix (AFGSM) as a comparative study. A different approach called as effective rod model is applied to circular/T‐shaped dielectric support rod helix SWSs in order to obtain ladder circuit representation of one turn of related helix SWSs for the first time. Scattering matrices of equivalent circuit representation of interested helix SWSs are obtained by using microstrip line model of helix SWS which slits helical tape at the effective helix radius along the direction normal to the helix winding direction and flattens it out for the EFA, the AFGSM, and the CMA methods. Additionally, comparisons are given for investigated methods together with the results of Computer Simulation Technology (CST) design environment, and good agreement has been observed among numerical results of different helix SWSs in a broad frequency range.

AUTO-APPRAISAL OF VOLTAGE RATING FOR SWITCHED-CAPACITOR DC-DC CONVERTERS

Resonant Switched Capacitor (SC) DC-DC converters are showing potential for use in medium to high-power applications. The high-cell count in these applications means that for a given voltage conversion ratio there are theoretically a large number of alternative topologies that can be synthesised. However, each of these topologies may exhibit different competing characteristics, for example total VA rating of capacitors, total VA rating of switches, number of switches and individual switch voltage rating. Obtaining an optimum topology in terms of given design constraints is therefore important requirement. This paper builds on previous work by the authors by presenting a method for the automatic calculation of the voltage ratings of the components in a SC converter. This result along with earlier work, allows for the calculation of VA ratings, which are an important metric when comparing competing circuits. In addition, a new Canonical Cell topology is presented that extends the range of SC circuits that can be analysed using this method, to cover so-called Ladder circuits. The method is validated against detailed Spice simulations and measurements from a hardware prototype.

Numerical Analysis of Magnetic Soliton Excited on Nonlinear LC Ladder Circuit Array Using Permanent Magnet Flux Biased Inductor

A soliton is a unique wave that maintains its shape and constant velocity. It has been observed widely in natural nonlinear systems. In particular, a magnetic soliton has been observed experimentally on a nonlinear <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> ladder circuit array. The aim of this article is to excite a magnetic soliton on the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> ladder circuit array using a permanent-magnet-flux-biased (PMFB) inductor. Electromagnetic analysis reveals that the PMFB inductor has exponential inductance characteristics due to the effective use of magnetic saturation in the stator core. Four PMFB inductors with different magnetic circuit topologies are analyzed and compared, to decrease the inductor current. Finally, this article numerically solves the loop equation for the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> ladder circuit array and shows that the magnetic soliton is successfully excited and propagates without changing its shape and velocity. This technique is equivalent to a rotating magnetic field and has a great potential in developing new ac motors or actuators.

WITHDRAWN: Energy storage system solution – A cell balancing circuit

This research work assesses the cell balancing capacities of various commercial off-the shelf (COTS) super capacitor chargers to ultimately promote the design along with implementation of energy storage systems that are based on super-capacitors. Extensive simulations are executed with the manufacturer’s system and RC ladder circuit models. These work also observers the porous electrode structure and charges redistribution. It is also observed that the series resistance (ESR) equivalent supercapacitor may have quite significant effect on the variance of terminals voltage.

In-plane characterization of PZT thin films for the creation of a general impedance model

The in-plane dielectric and ferroelectric properties of preferentially oriented lead zirconate titanate (PZT) thin films are characterized using interdigitated transducers (IDTs). By combining finite element method simulations and capacitance measurements, values of the dielectric constant of films with thicknesses between 150 nm and 800 nm are obtained. A modified Sawyer–Tower circuit is used to investigate the polarization loops measured in-plane using IDT electrodes. A well-defined hysteresis loop is obtained demonstrating the switching of the polarization of the ferroelectric domains. Leakage current measurements reveal high resistivity and are an indication of the high quality of the PZT film. The obtained characteristics are used to determine the total impedance of the IDT-PZT structure. Here, the structure is represented by an equivalent ladder circuit using the inductance and resistance of the IDT electrodes and the capacitance and conductance of the PZT film. The obtained total impedance matches low frequency measurements.

Four-Port Symmetrical Reflectionless Lumped Filter/Diplexer: Prototype and Design Table

It is shown that a well-designed lumped $LC$ loop network with a phase inverter can exhibit perfect reflectionless filtering response at its all four ports. The network is composed of two pairs of symmetrical $LC$ ladder circuits, in which one pair is obtained from lowpass transformation at a prescribed frequency based on a special lowpass prototype, and the other pair is from highpass transformation based on the same prototype at the same frequency. The input power, at any port, is divided into the two adjacent ports in the frequency domain through different paths of the loop. Each path between any two ports nearby can be treated as a mono-functional filter, whereas the adjacent two paths work as two filters with complementary responses. The overall circuit performs as a generalized diplexer without a specified “common” or “separation/combination” port. By using a numerical equation solver, the element values of the reflectionless lowpass/highpass prototype filter of order one, three, five, and seven are given. Then, the values of order nine, eleven, thirteen, and fifteen are obtained by using the optimization method. Other filtering functions such as bandpass/bandstop or dual-band can be easily implemented with the proposed prototype by using the standard frequency transformation method. For verification, two sample filters are fabricated and measured. The experimental data agree well with the predictions.

Self‐sustained solitary waves in a tunnel diode oscillator lattice and their applications in frequency division

SummarySelf‐sustained solitary waves, which propagate in a one‐dimensional lattice of tunnel diode (TD) oscillators, can be effectively applied to frequency division. In this work, it is experimentally observed that the properties of a solitary wave strongly suggest that it is the discretized counterpart of the homoclinic pulse predicted in a quasi‐continuous model of a TD oscillator lattice. Generally, these self‐sustained waves annihilate during a head‐on collision. Owing to this phenomenon, a TD oscillator lattice acts as an efficient frequency divider through its simple connection to an ordinary LC ladder circuit. In this work, both the pair annihilation of pulses and a 2:1 frequency division ratio are successfully observed experimentally.

Feasibility evaluation of new electric motors driven by intrinsic localized mode

Intrinsic localized mode (ILM) has been observed in various physical systems. In particular, electromagnetic ILM has been observed on an LC ladder circuit array. This paper focused on the electromagnetic ILM and aims to evaluate the feasibility of a new electric motor driven by the electromagnetic ILM numerically. First, we propose two types of nonlinear inductors with different geometries, and their magnetic saturation characteristics are clarified from the magnetic field analysis. Second, numerical simulations using the obtained parameters show that the moving velocity of a moving ILM varies with an initial voltage disturbance. Finally, we propose an inductor with permanent magnets placed on a surface of a rotor core, aiming to generate the electromagnetic ILM more efficiently. Numerical simulations show that the behavior of the moving ILM is affected by the rotational speed of the rotor.