Electronic Circuit Simulation Research Articles

Simulation method for DSP-controlled active PFC high-frequency power converters

A generic simulation approach for digital-signal-processor (DSP) controlled power converter systems is described. Software program statements for simulating a feedback control scheme could also be incorporated in the software code of a DSP-controlled power conversion system. The power electronic circuit simulation technique is based on the substitution of switch-modulated resistors in place of all the active and/or passive power switches; one state equation described by state variables, i.e. inductor currents and capacitor voltages, and the solution of the state equation is computed by an appropriate numerical method. The simulation approach is explained by a practical application example of the DSP-controlled active-switch three-phase power-factor-correction (PFC) converter system.

Electronic-network modelling of rechargeable NiCd cells and its application to the design of battery management systems

In the first part of this paper, the development of a simulation model for a sealed rechargeable NiCd cell is described. Based on the concept of this cell type, a mathematical description of the various physical and electrochemical processes occurring inside the cell can be given. Subsequently, these equations are introduced in the form of electronic components into an electronic-circuit simulator. This enables the user to simulate the most important cell characteristics like voltage, temperature and internal gas pressure simultaneously and coherently under a wide variety of charging, discharging and open-circuit conditions. The construction of the model enables the user to investigate the course of each of the various reactions taking place inside the cell. Moreover, the electrical and thermal interaction with the surrounding electronics attached to the cell and with other cells, e.g., in a battery pack, can also be simulated. In the second part of this paper, some examples of simulations of cell characteristics are presented. The results of the simulated phenomena show good qualitative agreement with measured cell characteristics. An understanding of phenomena such as charge efficiency, self-discharge and overdischarge is presented using the model. Simulation of battery behaviour in an electronic system enables a system designer to design the optimal Battery Management System around the battery. In the third part of this paper, an example of applying the model in an electronic system is given, i.e., a shaver. Also, simulations of several cells connected in series forming a battery or battery pack are described.

Electronic Circuit and System Simulation Methods [Book Reviews

Electronic Circuit and System Simulation Methods [Book Reviews

THE SUPERCOMPUTER TOOLKIT AND ITS APPLICATIONS

The Supercomputer Toolkit is a family of hardware and software modules from which high-performance special-purpose computers for scientific/engineering use can be easily constructed and programmed. The hardware modules include processors, memory, I/O devices and communication devices. The software modules include an operating system, compilers, debuggers, simulators, scientific libraries, and high-level front ends. When faced with a suitable problem, the engineer/scientist connects the modules by means of static-interconnect technology and constructs a problem-specific parallel computation network. The network is loaded from a workstation that serves as a host. When the program is run, results are collected and displayed by the host. The host handles files, does compilation, etc. The computation network, the Toolkit, does the heavy computation. In addition to high performance, the advantage of the Toolkit is its low cost which makes it potentially affordable by small groups as their main number crunching computer. This paper is concerned with the Toolkit version built at the Technion, which is a second generation of the MIT version.1 The paper briefly describes the hardware and software of this new version and its application to elastic-plastic flow, weather prediction and the simulation of electronic circuits. The main topic of the application section is the relation between the Toolkit configuration and the computation structure of these applications. The paper discusses conclusions related to the hardware and software as well as to the techniques for applying the system.

Electronic circuit simulation in a mixed-language environment

Simulation of complex systems, that include analogue and digital circuitry and even non-electrical devices, may be simplified if libraries developed in different hardware description languages can be used in one design. This paper describes a method of co-simulation with Alecsis simulator/language environment and VHDL pre-developed libraries. Mixed-signal co-simulation results are presented.

Computer simulation of the transmission of modulated signals through linear analog circuits using fast Fourier transforms

An algorithm is proposed for computing transformations of modulated signals in linear circuits by the spectrum method and by applying fast Fourier transforms. The algorithm computes transformations of oscillations with complex modulation and large angle modulation indexes in analog circuits. The accuracy of the proposed method is discussed. A program is described for analyzing modulated oscillations in linear selective circuits that complements the known electronic circuit simulation programs.

Generalised TLM switch model for power electronics applications

A generalised model of a switch suitable for power electronic circuits simulation, based on the transmission-line modelling or matrix (TLM) method, is presented. It consists of an inductive stub model terminated by a resistance having a small or large value depending on whether the switch is on or off, respectively. In the previous TLM switch model, a series resistance is always required to be added to the model to represent the voltage drop during the conduction state, whereas in the new proposed switch model, depending on the state of the switch, the on or off resistance forms an integrated part of the model, To demonstrate the application of the generalised TLM switch model, a voltage-source inverter (VSI) feeding an inductive load was considered. Results from the simulation are in complete agreement with expected theoretical waveforms.

An efficient technique for the time-domain simulation of power electronic circuits

A general-oriented time-domain simulation algorithm for power electronic circuits is presented. The methodology is based on stepwise quadratic formulation of circuit state variable trajectory with progressive analysis of switches' operation. At each simulation step, the circuit topology is transformed into a purely resistive network which is analyzed by the modified nodal analysis (MNA) technique. The rate of change of each state variable is determined by its parasitic resistance and instantaneous value. The trajectory of each state variable and switch branch voltage is expressed by a quadratic description. A simple and efficient method is used to determine the switching instants of circuit topologies. The prominent features of this approach include: (1) its simplicity in solving resistive network only throughout the analysis without dealing with any complicated Laplace-transformed equation or differential formula; (2) its generality in determining valid circuit topology without prior understanding of the switching relationships; (3) its directness in calculating the switching instants; and (4) its inherent consideration of the parasitic resistance of each reactive element in the analysis. Two examples illustrating the generality and computational efficiency of the proposed algorithm are presented. The simulated results are favorably compared to the method used in available literature and the commercial software, PSpice.

Correction to Authors'-reply To "Discussion On "Simulation Of Power Electronic Circuits Using Sparse Matrix Techniques"

Correction to Authors'-reply To "Discussion On "Simulation Of Power Electronic Circuits Using Sparse Matrix Techniques"

Computer-aided analysis of power electronic circuits by stepwise topological identification

A new approach for the time-domain simulation of power electronic circuits is developed. The methodology is based on stepwise identification of circuit topology. The simulation process automatically looks for a valid topology in every step. At each simulation instant, the circuit topology is transformed into a resistive network, giving another superior feature of this method: the avoidance of solving complicated s-domain or differential formulas. No small-signal approximation is assumed. Parasitic resistance of the reactive element is included in the circuit model. Several examples illustrating the generality and computational efficiency of this new method are presented. The simulated results are favourably verified with experimental measurements and available literature. © 1997 John Wiley & Sons, Ltd.

Behavior-mode simulation of power electronic circuits

In this paper, a systematic approach for the behavior-mode simulation of power electronic circuits is presented. To solve the problem of switch-state detection in behavior-mode simulation, a simple-to-implement reinitialization technique is introduced. Furthermore, the issue of time-step selection is discussed. It is illustrated through examples that behavior-mode simulation complements the detailed-mode simulation and enhances the efficiency of the computer-aided analysis and design of power electronic circuits.

Discussion on "Simulation of power electronic circuits using sparse matrix techniques" [and reply

In the original paper (Vasudevan et al., see ibid., vol. 42, no. 4, p. 409-13, 1995), the authors claimed the speeding-up of a modified nodal method developed by Sudha et al. (Ref. [3] in the original paper) by using sparsity programming and resistance modeling of the switches, instead of the inductor modeling used in Ref. [3]. As a co-author of Ref. [3], the author wishes to point out that Krishna et al. have not implemented the algorithm in Ref. [3] in the proper manner, while making comparisons for computational speedup. He details how, if sparsity methods are used in the algorithm given in Ref. [3], the computation times can be reduced much more than that given in the paper under discussion.

Simulation of power electronic circuits with principles used in wave digital filters

Simulation is a well-known technique to study complex systems. This paper introduces a new simulation technique based on the theory of wave digital filters. They are candidates to substitute classical analog filters by digital electronic circuits in signal processing. In addition, they show advantages compared with other classes of digital filters such as fast algorithms and simple models of electric components. Therefore, the theory of wave digital filters is used to build a new simulator for transient simulation. So far, the properties of this simulator permit a fair comparison between the new simulation technique and well-known simulation programs. The new simulator is easily linked to a CAD program to design and optimize switch mode power supplies already in use in industry.

Dynamic electric arc model for electronic circuitsimulation

The authors present a physics based electric arc model which can simulate both static and dynamic characteristics of an arc load controlled by an electronic circuit. The proposed model was developed from modifications of the classical Cassie and Mayr equations. It has been test implemented in the Saber circuit simulator. There has been a considerable degree of correspondence between the simulated and experimental results.

Concurrent programming and simulation of decoupled power electronic circuits

The authors describe the parallel simulation of a multistage power electronic circuit using the transmission line modelling (TLM) method. In this approach, a large stiff circuit can be decoupled into smaller subcircuits by TLM links. Each subcircuit is then formulated with a small system matrix and simulated in one program module. The overall simulation is done by running all the program modules in parallel. This parallel simulation allows significant speed improvements over normal sequential simulation, as shown by the results of numerical experimentation.

A rational formulation of thermal circuit models for electrothermal simulation. II. Model reduction techniques [power electronic systems

For pt. I see ibid., vol. 43, no. 9, p. 721-32 (1996). To increase the efficiency of the electrothermal simulation of power electronic circuits and devices, model reduction techniques are applied to develop reduced thermal circuit models of Si chips, thermal packages, and heat sinks. Both the Modal Superposition method and a Component Mode Synthesis method are presented together with a model error estimation and a Ritz vector method. An alternative method for substructuring is also included. The reduced thermal circuit models are verified and implemented in the SABER circuit simulator. The electrothermal model of a full-bridge converter is simulated employing the proposed approach, and the results discussed.

INTERVAL ANALYSIS IN POWER ELECTRONICS

The use of Interval Analysis for numerical simulation of power electronic circuits is discussed in this paper. It is shown that Interval Analysis is an optimal tool for such kind of applications since switching circuits operate upon sequences of time intervals bounded by instants that are zeros of non-linear non-monotonic functions. The main advantages offered by Interval Analysis are pointed out in the context of a new approach proposed to solve the problems of steady-state and transient analysis. In particular, it is shown that for steady-state analysis a robust and fast IA-based method can be adopted which generates a sequence of virtual solutions that converges towards the right steady-state solution within few iterations, without any prior knowledge about the mode of operation of the circuit. Some examples of applications are proposed, including chaos, subharmonics and circuit collapse.

A new algorithm for two-dimensional numerical continuation

Consider a smooth mapping F from R n+2 into R n; such a mapping can be interpreted as a system of n functions in n + 2 unknowns. The zero-set of the mapping is typically a smooth two-dimensional manifold (surface) embedded in the ambient space of dimension n + 2. Our paper describes a numerical algorithm for generating a representation of such a surface which can be displayed graphically. The defining equations are given in implicit form; not only is such a formulation convenient, but it allows surfaces with “folds” in which there is not a functional relationship between the n state space variables and the two distinguished continuation parameters. The algorithm is built as a layer on top of an existing one-dimensional continuation solver, and has been successfully applied to problems with a high-dimensional state space using efficient sparse matrix techniques. Applićations in electronic circuit simulation are described.

Generic circuit response interpolation for robust design

In electronic circuit simulation in the frequency domain the response is a function of frequency, g( omega ). Typically, to estimate g( omega ) the circuit is simulated at a large number of frequency points omega0, and to optimise the circuit a large number of simulations are made. A method for reducing the number of frequency points needed to estimate circuit response is presented in this paper. From an initial base simulation of the circuit an estimate of g( omega ) is developed using a parametric statistical model from a fixed subset of omega0, namely omega1, carefully selected using the proven statistical method of cross-validation combined with simple thinning out of omega ,. The estimated model is used in conjunction with results from future simulations made at the reduced frequency set omega1, to estimate g( omega ) when the circuit is run under different input conditions, providing an efficient method of circuit optimisation. The method is illustrated with an example which explores the effect of reducing frequency points for simulation on model accuracy. This shows the number of frequency points can be significantly reduced while still estimating the response curves accurately.

Simulation of power electronic circuits using sparse matrix techniques

Transient simulation of power electronic circuits is of considerable interest to the designer. The switching nature of the devices used permits development of specialized algorithms which allow a considerable reduction in simulation time compared to general purpose simulation algorithms. This paper presents some sparsity oriented methods to speed up the simulation of transient behavior of such systems. Test results obtained for typical circuits confirm the efficiency and accuracy of the proposed methods.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>