Mutator-Based Meminductor Emulator for Circuit Applications

A mutator-based meminductor emulator whose inductance can be varied by an external current source is proposed. The implementation of a meminductor emulator is very important, since real meminductors are not physically realizable with current technology. Though there is active research on memristor or memcapacitor emulators, no significant contribution for the meminductor emulator has been presented yet. In this paper, a meminductor emulator has been built using the principle of a mutator, in that a memristor with \(v-i\) at one port functions as a meminductor in the other port, whose input is characterized by \(\varphi - i\) curve. It is shown that multiple meminductor circuits can be built in various configurations with memristors combined with a single mutator. The feasibility of our meminductor emulator and its expandable configurations are verified experimentally and SPICE simulation.     

基于Matlab的忆感器建模仿真及应用

忆感器是一种有记忆能力的非线性电感器,其电感值的变化依赖于流过它的电荷数或磁通量。对于这种新的纳米级的电子元件,从电路学的基本原理出发,推导了它的基本公式,从数值分析的角度提出了一种新的基于Matlab的忆感器的建模及仿真方法,验证了忆感器的典型的磁滞回环现象,并利用这种方法重点分析了忆感器在非易失性存储和人工神经网络中的应用。实验表明,该建模方法准确地反映了忆感器的特性,同时也说明了忆感器在众多的领域里具有很高的潜在的应用价值。     

忆阻元件的研究进展

忆阻元件是一种联系电荷和磁链之间关系的新的无源电路元件,可以称其为第四类基本电路元件。本文首先介绍了忆阻元件的概念、基本模型及其数学表示方法,然后介绍了目前国内外的研究现状。国内研究主要集中于忆阻元件的数学模性、特性及与其它元件组成的简单电路的性能;国外的研究主要集中于忆阻元件在各方面的潜在应用以及由忆阻概念进一步推测忆容和忆感元件及其系统。     

Frequency-domain steady-state analysis of circuits with mem-elements

The paper deals with frequency-domain models of memristor, memcapacitor, and meminductor, and their use in the steady-state analysis by means of the harmonic-balance method. The models are based on a polynomial approximation of constitutive relations, allowing analytical formulation of relations between the spectral components of stimulus and response, for both periodic and quasi-periodic steady-state conditions. The method does not require transforming signals between the time and the frequency domains to obtain the mem-element response. Examples of the analysis of a mem-resonance circuit with long settling time and the HP memristor with nonlinear dopant drift are presented.     

Meminductor Response Under Periodic Current Excitations

Recently, the mem-elements-based circuits have been addressed frequently in the nonlinear circuit theory due to their unique behavior. Thus, the modeling and characterizing of the mem-elements has become essential, especially studying their response under any excitation signal. This paper investigates the response of the meminductor under DC, sinusoidal, and periodic current signals for the first time. Furthermore, a meminductor emulator is developed to fit the obtained formulas which are built using commercial off the shelf components. The proposed analysis offers closed form expressions for the meminductance for each case. Moreover, many fundamentals and properties are derived to understand the responses such as the maximum saturation time in case of the DC response. A general closed form expression for the meminductance is derived under any periodic waveform, and this formula has been validated by applying a square wave as an example.     

忆感器的Simulink模型及其特性分析

忆感器是一种具有记忆功能的非线性电感器。根据忆感器的数学模型,建立了Simulink仿真模型,并由该模型的仿真结果得到关于忆感器的典型特性,验证了模型的有效性。研究了不同参数对忆感器特性的影响。根据该模型,磁控忆感系统的建模也可以采用类似的方法。     

Realizations of mutative 4-ports and their applications to memstor simulations

In this paper, in addition to the universal 4-port mutator circuit introduced earlier with an adder and a subtractor block, two more 4-port mutator circuits, one with plus type (CCII+) and minus type current conveyors (CCII?), the other with a plus type current conveyor (CCII+) and one minus type current follower (CF?) are presented, their port relation matrix and their realization of different memstors are tabulated. How the transfer characteristics of the ideal mutative 4-ports with respect to frequency hold is verified using their transistor level simulations. By terminating properly two ports of the mutative 4-port simulations of a memristor with three different mutators, of a meminductor and of a memcapacitor are presented and compared also with some mutators existing in the literature.     

Electronically tunable high frequency single output OTA and DVCC based meminductor

Analog Integrated Circuits and Signal Processing - This research article reports electronically tunable high-frequency meminductor based on single output operational transconductance amplifiers...     

A new electronically controlled floating/grounded meminductor emulator based on single MO-VDTA

Analog Integrated Circuits and Signal Processing - This paper proposes a circuit configuration to emulate the behaviour of a floating/grounded incremental/decremental flux-controlled meminductor,...     

一种改进磁链计算模型分析

准确获取异步电动机转子磁链信号在高性能电机控制系统中具有十分重要的意义。介绍了常用转子磁链计算的电压和电流模型,针对各自存在的部分问题,提出了一种基于磁链计算方程进行组合的改进计算模型。在此基础上,根据矢量控制理论,采用Matlab／Simulink软件设计了异步电机矢量控制系统。仿真结果表明了该理论的正确性和可行性。     

Flux pinning in a slab model of grain and twin boundaries

The flux pinning potential and critical current of a grain and a twin boundary are evaluated for a S-S’-S junction model and a configuration of parallel magnetic field and junction plane. In the grain boundary model, the S’ domain is assumed to be disordered, to mimic oxygen disorder. Large critical currents ≈O(10⁶ amp/cm²) are estimated for both models. The grain boundary model exhibits a “nonweak” link behavior and moderate critical current dependence on the grain misalignment angle. We briefly dicuss an approach to enhance critical currents based on our grain boundary model.     

电励磁同步电机两种电流模型磁链观测器的比较

在低速时,电压模型测量不准确,对电励磁同步电动机磁链观测需要使用电流模型。本文讨论了基于磁链幅值给定和基于定子电流两种电流模型,给出两种电流模型的基本原理和控制框图,并在Matlab/Simulink平台上对两种电流模型磁链观测器仿真研究,比较分析仿真结果,得到各自优缺点。     

Study on Time Domain Characteristics of Memristive RLC Series Circuits

The notion of memristive system was first proposed in 2009. This concept of memory element has been extended from memristors \((\hbox {R}_{\mathrm{M}})\) to memcapacitors \((\hbox {C}_{\mathrm{M}})\) and meminductors \((\hbox {L}_{\mathrm{M}})\). Currently, the above elements are not available as off-the-shelf components. Therefore, based on the realization of a light-dependent resistor (LDR), memristor analog model, memcapacitor and meminductor analog circuit models based on \(\hbox {R}_{\mathrm{M}}-\hbox {C}_{\mathrm{M}}\) and \(\hbox {R}_{\mathrm{M}}-\hbox {L}_{\mathrm{M}}\) converters are first introduced. Then, instead of the traditional resistor, capacitor, and inductor, memristor-, memcapacitor-, and meminductor-equivalent circuits are used to determine the time domain characteristics of the RLC-mode circuits with mem-elements. These circuits are discussed in detail, and in particular, the phenomena caused by the memory characteristics of the mem-elements are studied. This research provides an important reference for further research into mem-element applications in circuit theory.     

Modeling of ionizing radiation effect on optoelectronic-integrated devices (OEIDs)

The ionizing radiation effect on the static and dynamic behavior of an optoelectronic-integrated device composed of a hetrojunction phototransistor and light-emitting diode is studied theoretically. First, the device characteristics before irradiation are investigated based on the equivalent circuit of the constituent devices and the optical feedback inside the device. Second, the effect of neutron irradiation flux on transient behavior of this device is theoretically studied. It was noticed that, the neutron irradiation flux reduces the transient response in both the amplification and switching modes. Also, neutron irradiation flux increases the switching voltage of the device and decreases the output current, this means that the ON state device which exposed to this irradiation flux will turn to the OFF state because it will need higher value of switching voltage. Either increasing the amount of input light or the applied voltage is required to turn the device to the ON state again. This type of models can be exploited as optical amplifier, optical switching device and other applications.     

助焊剂各成分作用浅析

根据助焊剂的研究现状,文章对助焊剂各主要成分的作用进行了介绍,主要阐述了其中活性成分的作用及机理,并对助焊剂性能改进提高的方法及方向进行了归纳和展望。     

鼠笼电机程控混合模型仿真研究

磁链观测是矢量控制中的一个关键任务,电流模型在转速较低时比较精确,电压模型在转速较高时比较精确。结合两种模型使其依靠程序自动切换,在转速较低时使用电流模型,在转速较高时采用电压模型,可以对磁链进行准确的观测。以Matlab/Simulink为工具,采用程控自动切换混合模型对异步电机矢量控制算法进行了仿真。仿真结果验证了程控自动切换的可行性和矢量控制调速的动态响应快、硬特性强、稳态脉动小的良好性能。     

以磁通等效实现磁悬浮轴承磁极容错控制

针对8磁极电磁轴承容错控制问题,文中提出了一种基于磁通等效的电磁轴承容错控制方法。该方法首先通过仿真得到磁通的电流-磁通影响系数,利用线性代数理论计算得到电流分配矩阵。当某一个磁极回路发生故障时,利用电流分配矩阵计算重构电流,使8个磁极端面的磁通在故障前后保持不变,即磁通等效,从而实现容错运行。在ANSYS有限元仿真平台进行仿真,用磁通等效方法可以较好地还原故障前的端面磁通和磁力线分布,并计算得到了磁通误差(最大不超过3.2%,绝大部分小于0.5%)和力误差(最大不超过7%,绝大部分小于1.5%),证明了所提出磁通等效容错控制方法的有效性。     

Penetration of magnetic field into high-temperature superconductors

The penetration of a monotonically time-increasing magnetic field in high-temperature superconductors (HTSC) slabs with the power law dependencies of the critical current density and resistivity on the magnetic field is investigated theoretically. It is shown that the asymptotic solutions of the extended critical state model correspond to the cases of the classical critical state model and the model of viscous flux flow without pinning. The ranges of the applicability of these models and the conditions for the transition from one model to the other are determined. These theoretical conclusions explain experimental data presented in scientific literature     

A new current model flux observer for wide speed range sensorless control of an induction machine

A new closed loop current model flux observer is designed to estimate the rotor flux, position and velocity of an induction machine. The current observer includes carefully designed sliding mode functions which are derivative of the fluxes along the /spl alpha/ and /spl beta/ axes. Therefore, when the estimated current converges to the measured one, the flux estimation is a mere integration of the sliding mode function. The rotor speed can then be derived from the sliding mode functions and the estimated flux. In the current and flux observers all of the terms that contain the rotor time constant and the rotor speed have been replaced by the sliding mode functions, thus making the proposed current and flux estimations completely insensitive to the rotor time constant variation and any error in the estimated speed. Simulations and experiments are performed under a variety of conditions to validate the effectiveness of the proposed algorithm.     

太阳同步轨道卫星空间热流分析

卫星空间热流的计算是卫星可见光特性与红外特性分析的基础,本文首先建立了基于蒙特卡洛法的卫星空间热流计算模型,然后计算了太阳同步轨道对地三轴稳定卫星在轨运行一个周期内所接受的空间热流,最后对卫星的空间热流计算结果进行了详细分析,研究结果对于空间目标可见光特性与红外特性研究具有参考价值。