A tabular source approach to modelling and simulating device and circuit noise in the time domain

Simulation of device and circuit noise at low frequencies is often carried out as part of a small‐signal ac analysis. Moreover, circuit simulators with rf analysis capabilities usually specify circuit performance in terms of S parameters and model high‐frequency noise in terms of noise waves and correlation matrices. It is also unusual to find circuit simulators that extend noise simulation to the time domain. This is particularly true for software packages developed from SPICE 2g6 or 3f5. This paper introduces a simple tabular noise source technique, which adds time‐domain noise to semiconductor device models and integrated circuit macromodels. The proposed technique is suitable for use with any general purpose circuit simulator. To demonstrate the power of the suggested approach the text describes time‐domain noise extensions to the SPICE diode, BJT, JFET, MOSFET and MESFET models. These noise extensions have been implemented and tested with the ‘Quite universal circuit simulator’ (Qucs). Copyright © 2011 John Wiley & Sons, Ltd.     

基于耦合电感的直流故障限流器

柔性直流电网存在故障电流上升速度快、幅值高,感性元件储存能量大等问题,这造成故障电流难以分断,并且使得直流断路器的耗能支路承受巨大压力。为了限制故障电流峰值并且降低直流断路器耗能压力,提出一种基于耦合电感的直流故障限流器。当发生短路故障时,该故障限流器利用电感耦合特性等效投入电阻与电容组成的限流支路,以实现无延时的故障限流;当直流断路器分断故障电流时,该故障限流器利用耗能电阻耗散耦合电感储存的能量,从而分担直流断路器耗能压力,以达到降低避雷器容量需求、加快故障电流分断速度的目的。大量电磁暂态仿真结果表明,所提故障限流器具有良好的限流效果,能极大降低直流断路器的耗能压力。且该故障限流器制造成本低,易于实现。     

An effective approach to obtain model parameters for BJTS and FETSfrom data books

The authors address the problem of obtaining the values of small signal parameters of the high frequency hybrid-π models of bipolar junction transistors (BJTs) and junction FETs (JFETs) for a given set of bias conditions from the data-book values. They also show the methods of determining the 'typical' values of the input parameters to be used in the model statements of circuit simulators, such as SPICE     

电力系统数字混合仿真技术综述

相互独立的机电暂态程序与电磁暂态程序由于各自的不足和局限,已经难以适应快速发展的现代电力系统对仿真技术的要求,数字混合仿真技术为解决该问题提供了一种新的思路。文章对该技术进行了研究,认为接口的处理是其中的关键,在此基础上重点阐述了接口位置选择、等值电路形式、数据交互方式以及数据转换等核心问题。最后指出,在混合实时仿真中电磁暂态侧与实际物理装置相连具有重要的研究价值和应用前景。     

Memcapacitor emulator based on the Miller effect

This work provides the guidelines to design and implement an elemental memcapacitor circuit emulator based on the relation between memcapacitance and the Miller effect in voltage amplifiers. The emulator is presented theoretically in a top-down approach, from the circuit behavior to the foundations of the constitutive equations of the memcapacitance and the electrical mutation of a memristor. Then, a practical and simple circuit implementation is demonstrated by SPICE computer simulations, circumventing the solid-state memristor by a two-state flux-dependent resistor, which modulates the gain of the amplifier in consonance to the flux of the input signal. Further electrical properties of the system are extracted from its physical implementation in a field-programmable analog array. The work is concluded illustrating the functionality of the memcapacitor emulator to study neuromorphic applications with a long-term potentiation example.     

Building intelligent tutorial systems for teaching simulation inengineering education

A framework for building intelligent tutoring systems (ITSs) to teach students the use of various simulation systems used in engineering education is described. Case studies to two widely used simulators in electronics education (LASAR, a digital logic simulator, and SPICE, an integrated circuit simulator) provide the basis of pedagogical methodology for teaching the use of simulators. This methodology is used to develop a tutorial environment which includes: an authoring system that enables an instructor to develop and tailor the course contents; and a course presentation system that communicates this information via a direct manipulation interface to the user. The student perceives the tutorial as a hypertext network which can be freely explored; however, the tutoring system monitors and dynamically reconfigures the accessible information according to the level and attainment of expertise by the student. The environment includes components to monitor and evaluate the performance of the student. This tutorial framework is used to create intelligent tutorial systems for SPICE and LASAR     

IGBT电力电子系统小时间尺度动态性能分析与计算的电磁场-电路耦合模型

为了解决现有模型不完全适用于小时间尺度电力电子系统瞬态性能分析与计算的不足,建立用于IGBT电力电子系统小时间尺度动态特性分析、计算的三维电磁场-电路耦合计算模型,并提出其求解的迭代计算方法。为精确描述小时间尺度下IGBT内部瞬态电磁场及其分布规律,建立的IGBT本体三维有限元模型考虑位移电流、趋肤效应和引线邻近效应等复杂因素的影响;为考虑极小时间尺度下线路中杂散参数的电磁效应,高阶杂散参数电路模型采用多段等效电路模拟杂散参数的影响,同时采用谐态电磁场数值分析计算方法提取模型参数以考虑趋肤效应等的影响。基于IGBT内部电磁暂态过程的分析,提出一种改进的IGBT电路模型;为兼顾计算精度和计算时间的要求,提出等效高阶电路模型的一种降阶方法。仿真计算和实验测试结果证明了所建模型及求解方法的有效性和正确性。     

电力系统机电—电磁暂态混合仿真接口技术

在电力系统仿真中,相互独立的机电暂态程序与电磁暂态程序由于各自的不足和局限,已经难以适应快速发展的现代电力系统对仿真技术的要求;如果能在一次仿真过程中同时实现大规模电网的机电暂态仿真与部分电网的详细电磁暂态仿真,那么对详细分析系统特性具有重要的理论价值和现实意义.文章对该技术进行了研究,认为接口的处理是其中的关键,在此基础上重点阐述了接口位置选择、等值电路形式、数据交互方式以及数据转换等核心问题,并在实时数字仿真系统-RTDS平台下初步实现该技术.     

Circuit models of multiconductor shielded cables: incident plane wave effect

The present study examines the variation effects of incident plane wave on multiconductor shielded cables in frequency domains using Branin's method, which is referred to as the method of characteristics. The model operates in frequency and time domains with linear and nonlinear loads, respectively, which allows it to be easily introduced into circuit simulators, such as SPICE, Sabar, and ESACAP. Two examples are studied: coaxial shielded cables and shielded cables with two parallel wires (i.e., twinax cables), and they are both excited by an incident plane wave. The results obtained by this method are in agreement with those obtained by other methods. Copyright © 2015 John Wiley & Sons, Ltd.     

时延双PN结二极管电磁系统中的分岔与混沌现象

于一个由线性无损传输线加双PN结二极管非线性边界条件组成的简单电磁系统,通过行波分析理论确定了电压反射波的局部映射关系。应用混沌动力学理论分析了系统随参数λ变化而发生的分岔与混沌现象。研究表明:系统具有复杂的非线性动力学特性,表现出了非常丰富的非线性现象。     

A combined method of simulation of an electric circuit and field problems in the theory of induction heating

A combined method for numerical computation of the electromagnetic field in induction-heating systems is proposed and used. The method consists in a combination of methods of integral equations for the computation of the electromagnetic field in the area outside the load and methods of finite elements or finite differences for the computation of the electromagnetic field inside the load. A method of simulation of electrotechnical systems with simultaneous solving of circuit and field problems is proposed based on this method. Using the example of induction-heating devices, an external problem associated with the computation of circuit inductors, power supplies, and balancing capacitors and an internal problem related to the computation of the electromagnetic field and internal heat sources inside the load are formulated. The simulation of induction heaters is considered taking into account features of thyristor frequency converters with a parallel inverter.     

An early introduction to circuit simulation techniques

It is argued that introducing simulation tools such as SPICE at the undergraduate level can sometimes cause the students to lack an appreciation for circuit theory and solving circuits. Some undergraduates question the need to solve circuit problems by hand when SPICE can easily do the job for them. An approach to introducing circuit simulation to freshman students in order to motivate circuit theory and to instill an appreciation for the limitations of powerful computer aids such as SPICE is discussed. The approach is introduced as part of a pilot course: Introduction to Electrical and Computer Engineering     

Analytical estimation of propagation delay and short‐circuit power dissipation in CMOS gates

An efficient analytical method for calculating the propagation delay and the short‐circuit power dissipation of CMOS gates is introduced in this paper. Key factors that determine the operation of a gate, such as the different modes of operation of serially connected transistors, the starting point of conduction, the parasitic behaviour of the short‐circuiting block of a gate and the behaviour of parallel transistor structures are analysed and properly modelled. The analysis is performed taking into account second‐order effects of short‐channel devices and for non‐zero transition time inputs. Analytical expressions for the output waveform, the propagation delay and the short‐circuit power dissipation are obtained by solving the differential equations that govern the operation of the gate. The calculated results are in excellent agreement with SPICE simulations. Copyright © 1999 John Wiley & Sons, Ltd.     

Analog CMOS integrated circuit design: research and undergraduateteaching

The authors describe the use of software that was developed as part of a research program in analog CMOS integrated circuit design for an undergraduate course on analog VLSI design. The software includes some unusual uses of readily available, inexpensive, and easy-to-use programs available for microcomputers such as Macintosh or IBM-PC clones. Although initially intended to help with the design of CMOS operational amplifiers, the IC design method used is very general; other possible applications are described. The flexibility of these programs also allows them to be used with other CAD (computer-aided design) software, including circuit simulators and programs for schematic entry and layout. The software tools allow undergraduate students to complete analog CMOS integrated circuit designs using advanced CAD techniques but without being overwhelmed or losing touch with the underlying circuit design principles. Details of the programs and their use are presented together with the resulting analog IC designs fabricated using MOSIS (MOS Implementation Service)     

电力系统机电-电磁暂态混合仿真接口技术

在电力系统仿真中,相互独立的机电暂态程序与电磁暂态程序由于各自的不足和局限,已经难以适应快速发展的现代电力系统对仿真技术的要求;如果能在一次仿真过程中同时实现大规模电网的机电暂态仿真与部分电网的详细电磁暂态仿真,那么对详细分析系统特性具有重要的理论价值和现实意义。文章对该技术进行了研究,认为接口的处理是其中的关键,在此基础上重点阐述了接口位置选择、等值电路形式、数据交互方式以及数据转换等核心问题,并在实时数字仿真系统-RTDS平台下初步实现该技术。     

Circuit modeling for ultra‐wideband Tx‐Rx antenna systems based on frequency domain S‐parameters

This paper presents a circuit modeling procedure for Ultra‐wideband (UWB) Tx‐Rx antenna systems based on frequency domain S‐parameters. The modeling used an existing two‐port network's model consisting of four SPICE analog behavioral modules. The accuracy of the model has been validated by comparing its transient response with the measurement result using an oscillograph. This model can be used for the co‐design of the UWB Tx‐Rx antenna system with transmitters and receivers in circuit simulators. In the study, Tx‐Rx antenna systems using planar bow‐tie antenna and horn antenna with ultra‐wide bandwidths are used as examples. Copyright © 2010 John Wiley & Sons, Ltd.     

Analysing the operation of the basic pass transistor structure

Pass transistor logic has become important for the design of low‐power high‐performance digital circuits due to the smaller node capacitances and reduced transistors count it offers. However, the acceptance and application of this logic depends on the availability of supporting automation tools, e.g. timing simulators, that can accurately analyse the performance of large circuits at a speed, significantly faster than that of SPICE based tools. In this paper, a simple and robust modelling technique for the basic pass transistor structure is presented, which offers the possibility of fast timing analysis for circuits that employ pass transistors as controlled switches. The proposed methodology takes advantage of the physical mechanisms in the pass transistor operation. The obtained accuracy compared to SPICE simulation results is sufficient for a wide range of input and circuit parameters. Copyright © 2006 John Wiley & Sons, Ltd.     

电力系统机电暂态和电磁暂态混合仿真接口算法

传统的机电暂态或电磁暂态程序在分析日益复杂的大规模电力系统时,已开始显露出各自的局限性.将两者联合起来进行混合仿真,可以较好地解决仿真的规模、速度和精度的协调问题,这为研究电力系统的稳定性和动态特性提供了新的解决思路.文中系统研究了混合仿真中的接口算法,对机电侧和电磁侧的等值参数求取、等值电路形式及变换、电磁侧的基波等值复阻抗求解方法、机电侧正负序阻抗不等引起的不对称、电磁侧离散序列的基波提取等问题进行了深入分析,并且给出了具体的实现方案,为混合仿真平台的程序设计提供了坚实的理论依据.     

Role of the temperature distribution on the PN junction behaviour in the electro‐thermal simulation

Electro‐thermal simulations of a PIN‐diode based on the finite‐element method, show a non‐uniform temperature distribution inside the device during switching transients. Hence, the implicit assumption of a uniform temperature distribution when coupling an analytical electrical model and a thermal model yields inaccurate electro‐thermal behaviour of the PIN‐diode so far. The idea of including non‐uniform temperature distribution into power semiconductor device models is not new, as accurate electro‐thermal simulations are required for designing compact power electronic systems (as IC or MCM). Instead of using a one‐dimensional finite difference or element method, the bond graphs and the hydrodynamic method are utilized to build an electro‐thermal model of the PIN‐diode. The results obtained by this original technique are compared with those obtained by a commercial finite‐element simulator. The results are similar but the computation effort of the proposed technique is a fraction of that required by finite‐element simulators. Moreover, the proposed technique may be applied easily to other power semiconductor devices. Copyright © 2004 John Wiley & Sons, Ltd.