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In traditional linear network theory, the positive‐real (PR) criteria are widely used to judge the passivity of elements and networks in the light of the fact that there exists an equivalent relationship between the passivity and the PR property of their immittance functions (matrices). However, the equivalence will no longer hold when the fractional elements are introduced into the network, and the PR criteria are not suitable in complex frequency domain anymore. On the other hand, the rapid development of fractional‐order circuits and systems and the corresponding study in fractional circuit analysis and designs put forward an urgent requirement for the passivity criterion, which can tackle linear fractional networks. Hence, in this paper, we propose new passivity criteria for linear fractional networks by aid of generalized Tellegen's theorem and multivariable PR theory. By using the proposed criteria, the passivity of linear fractional networks can be judged, and the steps of the proposed criterion are illustrated by examples. 相似文献
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《International Journal of Circuit Theory and Applications》2017,45(5):595-612
Novel topologies of fractional‐order generalized filters are introduced in this paper. These offer the following benefits: (1) realization of lowpass, highpass, bandpass, allpass, or bandstop filter functions by the same topology; (2) resistorless realizations; (3) electronic adjustment of their frequency characteristics as well as their order; and (4) employment of only grounded capacitors. All the above have been achieved using Operational Transconductance Amplifiers as active elements and appropriate multi‐feedback topologies. The behavior of the proposed designs is verified through simulation results using the Cadence IC design suite and the Design Kit provided by the Austrian Micro Systems 0.35‐µm complementary metal–oxide–semiconductor process. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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《International Journal of Circuit Theory and Applications》2017,45(11):1514-1533
In this paper, the analytical solutions for the electrical series circuits RC, LC, and RL using novel fractional derivatives of type Atangana–Baleanu with non‐singular and nonlocal kernel in Liouville–Caputo and Riemann–Liouville sense were obtained. The fractional equations in the time domain are considered derivatives in the range α ∈(0;1]; analytical solutions are presented considering different source terms introduced in the fractional equation. We solved analytically the fractional equation using the properties of Laplace transform operator together with the convolution theorem. On the basis of the Mittag–Leffler function, new behaviors for the voltage and current were obtained; the classical cases are recovered when α =1. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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Costas Psychalinos Ahmed Elwakil Brent Maundy Anis Allagui 《International Journal of Circuit Theory and Applications》2016,44(11):2035-2040
Using fractional calculus, we analyze a classical switched‐capacitor integrator when a fractional‐order capacitor is employed in the feed‐forward path. We show that using of a fractional‐order capacitor, significantly large time constants can be realized with capacitances in the feedback path much smaller in value when compared with a conventional switched‐capacitor integrator. Simulations and experimental results using a commercial super‐capacitor with fractional‐order characteristics confirmed via impedance spectroscopy are provided. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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A. G. Radwan A. S. Elwakil 《International Journal of Circuit Theory and Applications》2012,40(5):533-538
We report a closed‐form expression of the voltage response of a current‐excited fractance device. The derived simple expression is made possible following the introduction of the generalized sine and cosine functions (rmsinα(t) and cosα(t)), which are valid on any fractional‐order surface and tend to the normal sin(t) and cos(t) at α = 1 or asymptotically as t→∞. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Georgia Tsirimokou Costas Psychalinos 《International Journal of Circuit Theory and Applications》2016,44(1):109-126
Fractional‐order blocks, including differentiators, lossy and lossless integrators as well as filters of order 1 + a (0 < a < 1), are presented in this paper. The proposed topologies offer the benefit of ultra low‐voltage operation; in addition, reduced circuit complexity is achieved compared to the corresponding companding schemes, which have been already introduced in the literature. The ultra‐low voltage operation is performed through the employment of metal oxide semiconductor transistors biased in the subthreshold region. The reduction of circuit complexity is achieved through the utilization of current mirrors as active elements for realizing the required building blocks. The performance of the proposed fractional‐order circuits has been evaluated through the Analog Design Environment of the Cadence software and the design kit provided by the Taiwan Semiconductor Manufacturing Company (TSMC) 180 nm complementary metal oxide semiconductor process. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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笼型感应电动机转子磁通的自适应观测 总被引：1，自引：0，他引：1
本文给出了笼型感应电动机转子磁通自适应观测器的设计方法。当电动机参数未知或发生变化时,观测器自动调整自身参数以确保观测精度。算法的稳定性和收敛性由具有严格正实误差传递函数的参数调整算法保证。数值仿真结果从各方面验证了算法的性能。 相似文献
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L. De Tommasi M. de Magistris D. Deschrijver T. Dhaene 《International Journal of Numerical Modelling》2011,24(4):375-386
The paper presents a new algorithm for the identification of a positive real rational transfer matrix of a multi‐input–multi‐output system from frequency domain data samples. It is based on the combination of least‐squares pole identification by the Vector Fitting algorithm and residue identification based on frequency‐independent passivity constraints by convex programming. Such an approach enables the identification of a priori guaranteed passive lumped models, so avoids the passivity check and subsequent (perturbative) passivity enforcement as required by most of the other available algorithms. As a case study, the algorithm is successfully applied to the macro‐modeling of a twisted cable pair, and the results compared with a passive identification performed with an algorithm based on quadratic programming (QPpassive), highlighting the advantages of the proposed formulation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Bülent Nafi Örnek Timur Düzenli 《International Journal of Circuit Theory and Applications》2019,47(6):813-824
In this paper, a boundary version of the Schwarz lemma is investigated for driving point impedance functions and its circuit applications. It is known that driving point impedance function, Z(s) = 1 + cp(s − 1)p + cp + 1(s − 1)p + 1 + ..., p > 1, is an analytic function defined on the right half of the s-plane. Two theorems are presented using the modulus of the derivative of driving point impedance function, |Z′(0)|, by assuming the Z(s) function is also analytic at the boundary point s = 0 on the imaginary axis with . In the obtained inequalities, the value of the function at s = 1 and the derivatives with different orders have been used. Finally, the sharpness of the inequalities obtained in the presented theorems is proved. Simple LC circuits are obtained using the obtained driving point impedance functions. 相似文献
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Georgia Tsirimokou Costas Laoudias Costas Psychalinos 《International Journal of Circuit Theory and Applications》2015,43(9):1105-1126
Novel configurations of fractional‐order filter topologies, realized through the employment of the concept of companding filtering, are introduced in this paper. As a first step, the design procedure is presented in a systematic algorithmic way, while in the next step, the basic building blocks of sinh‐domain and log‐domain integrators are presented. Because of the employment of metal–oxide–semiconductor (MOS) transistors operated in the subthreshold region, the derived filter structures offer the capability for operation in an ultra‐low‐voltage environment. In addition, because of the offered resistorless realizations, the proposed topologies are reconfigurable, in the sense that the order of the filter could be chosen through appropriate bias current sources. The performance of the derived fractional‐order filters has been evaluated through simulation and comparison results using the Analog Design Environment of the Cadence software and MOS transistor parameters provided by the Taiwan Semiconductor Manufacturing Company (TSMC) 180‐nm complementary MOS (CMOS) process. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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《IEEJ Transactions on Electrical and Electronic Engineering》2018,13(2):271-279
Time‐delayed interactions between DNA, mRNA, and proteins play an important role in the periodic somite segmentation of vertebrates. A mathematical model of the segmentation clock in zebrafish that illustrates the dynamics between proteins and mRNA has recently been proposed; however, the complexity of the model makes solving it analytically unrealistic. In this study, we derived a first‐order delay‐differential equation (DDE) model by following two heuristic reduction approaches: simplifying protein–mRNA interactions and protein dimerization. Then, we calculated the eigenvalues of the model and found that the maximum eigenvalue and the oscillatory dynamics are qualitatively equivalent when some parameters are varied. This result enabled us to illustrate the effectiveness of using eigenvalues to assess the dynamics of the reduced model. Further, we extended the reduction methods to a complete model of somite segmentation considering the interaction of four genes, and derived a reduced model with four variables and four delay terms. Although the oscillation period of our reduced model decreased by ∼10% compared to the original model, the amplitude differed by less than 10%. The dynamic features for genetic conditions are also qualitatively reproduced by the reduced model. Our model demonstrates that it is possible to identify key parameters and to reveal the interactions among the parameters. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
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介绍感应电动机矢量控制系统中转子磁场定向的一种自校准算法。该算法只需检测电动机的定子电流和转速信号，并由具有严格正实误差传递函数的参数调整算法保证其稳定性和收敛性。数值仿真实验说明了算法的性能。 相似文献
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L. Martínez J.J. Rosales C.A. Carreño J.M. Lozano 《International Journal of Circuit Theory and Applications》2018,46(5):1091-1100
In the last 3 years, the fractional conformable derivative and its properties have been introduced. Unlike other definitions, this new fractional derivative is based on the basic limit definition of the derivative and satisfies the same formulas of derivation, such as product and quotient of 2 functions and the chain rule. Using this new derivative, we obtain a new class of linear ordinary differential equations with noninteger power variable coefficients for the Resistance Capacitance (RC), Inductance Capacitance (LC), and Resistance, Inductance Capacitance (RLC) electric circuits. The numerical solutions are solved through the Matlab software. Solutions depend on time and on the fractional order parameter 0 < γ ≤ 1. The computing using this new derivative is much easier than using other definitions of fractional derivative. It has been shown that in the particular case γ = 1, these solutions become the ordinary ones. Also, a comparison has been made with the Caputo fractional derivative for the case of the RC circuit with constant source. 相似文献
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Today's advanced high‐speed technology requires building behavioral models of systems, from measured/simulated data, with increasingly higher operating frequencies. Different research efforts have come to light in literature for macromodeling, based on such types of data. Ensuring passivity is one of the most fundamental issues affecting system macromodeling, because system‐level performance can be unstable if even a single component of the system becomes nonpassive. Thus, from the computer‐aided design perspective, generation and provision of macromodels, while preserving passivity, is a significant challenge. In this paper, we carefully review novel techniques of passive macromodeling as well as their passivity verification and enforcement, from the early days to the present. We critically review the prominent methods in literature developed for macromodeling, and for verification and enforcement of passivity, and emphasize on their strengths and shortcomings. 相似文献
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This paper deals with a generalized method for the time‐domain solution of electrical networks. The aim is to explore a new technique for the numerical simulation of circuits considering linear, time‐varying and non‐linear cases. By using the wavelet transform of the electrical quantities, differentiation and integration in the time domain are replaced by matrix multiplication. Then, the classical circuit differential equations obtained by mesh‐current, node‐voltage or state variables methods are transformed in algebraic equations. The numerical efficiency of wavelets makes the method effective for a fast and reliable numerical circuit simulation. Comparisons with analytical solutions and PSPICE simulations are presented in order to evaluate the numerical characteristics of the proposed method. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
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Alexandre Yakovlev Alexander Kushnerov Andrey Mokhov Reza Ramezani 《International Journal of Circuit Theory and Applications》2015,43(10):1243-1262
A new model to predict the dynamic behavior of a self‐timed autonomous digital system powered by a capacitor is derived. The model demonstrates the hyperbolic shape of the discharging process on the capacitor. It allows a symbolic analysis of the discharging process for complex digital loads comprised of series (stack) and parallel configurations of digital circuits. For example, for a stack configuration, important non‐trivial relationships between the hyperbolic discharging rates have been derived based on the knowledge of the velocity saturation index (alpha) of the semiconductor devices used in the digital part. For a realistic (modern complementary metal oxide semiconductor (CMOS) devices) value of alpha = 1.5, the discharging process for a stack of two identical circuits proceeds nearly three times slower than that of any of the stand‐alone circuits. This shows a potential way of extending the lifetime of the energy sources by means of stacking self‐timed circuits. Although the analysis is based on configurations consisting of ring oscillators in CMOS technology, the analysis method can be extended to other types of self‐timed systems and other semiconductor technologies in which the instantaneous switching activity of the digital load is determined by the instantaneous voltage levels provided by the capacitive power transfer mechanism. The analytical derivations have been validated by simulations and experiments carried out with real hardware. © 2014 The Authors. International Journal of Circuit Theory and Applications published by John Wiley & Sons, Ltd. 相似文献
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George Souliotis Costas Psychalinos 《International Journal of Circuit Theory and Applications》2009,37(1):43-52
A novel current‐mode multiphase oscillator topology is introduced in this letter. This is realized by employing current amplifiers and only grounded capacitors. Attractive characteristics offered by the new topology are the electronic adjustment of the oscillation frequency, the absence of passive resistors, and the requirement of only grounded capacitors. Comparison with the corresponding already published current follower based structure shows that the proposed topology has better performance in terms of the number of required active elements, the employment of passive resistors, and the ability for electronic adjustment of the oscillation frequency. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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The term immittance converter refers to an impedance–admittance converter. The immittance converter has an input impedance that is proportional to the admittance of the load connected across output terminals. In this converter, the output current is proportional to the input voltage and the input current is proportional to the output voltage. Consequently, it converts a constant‐voltage source into a constant‐current source and a constant‐current source into a constant‐voltage source. It is well known that the quarter wavelength transmission line shows immittance conversion characteristics. However, it has a very long line length for the switching frequency, and is not suitable for power electronics applications. We thus proposed immittance converters that consist of lumped elements L, C and show improved immittance conversion characteristics at a resonant frequency. A three‐phase constant‐current source is proposed in this paper. It is possible to realize this by a simple circuit using an immittance converter. In this paper, circuit operation, characteristic equations, and results of simulation are described. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(4): 47–54, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20078 相似文献
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