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Article
Publication date: 1 April 1994

Z.R. Hu, P.A. Mawby, M.S. Towers and K. Board

The transient thermal behaviour, based on a rigorous transient thermodynamic treatment, of a power VDMOS transistor during turn‐off is presented. The time variation of the…

Abstract

The transient thermal behaviour, based on a rigorous transient thermodynamic treatment, of a power VDMOS transistor during turn‐off is presented. The time variation of the interior lattice temperature within the device is calculated by self‐consistently solving the fully coupled Poisson's equation and transient electron continuity equation together with the transient heat flow equation. The simulation takes account of temperature dependent heat conduction and capacity and includes thermoelectric currents due to temperature gradient. To make the transient thermal simulation more robust, a new analytical expression for heat capacity is used.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 13 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 April 1994

L Sabesan, AK Ray, P Mawby and M Towers

Modelling of a Twin ridge waveguide optical Amplifier is reported here. In this paper appropriate physical mechanism such as current spreading, carrier diffusion…

Abstract

Modelling of a Twin ridge waveguide optical Amplifier is reported here. In this paper appropriate physical mechanism such as current spreading, carrier diffusion, waveguiding and switching etc. have been take into consideration and the effects on characteristics and performance as a switch were investigated. With this model, physical phenomenon appropriate to the device can be analysed with respect to electrical, optical and geometrical parameters. Mixture of analytical and numerical techniques were employed.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 13 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 April 1994

J. Zeng, P.A. Mawby, M.S. Towers and K. Board

In this paper, the 2‐D numerical analysis is used to investigate the electro‐thermal performance of a trench power VDMOS transistor having a much reduced quasi‐saturation…

Abstract

In this paper, the 2‐D numerical analysis is used to investigate the electro‐thermal performance of a trench power VDMOS transistor having a much reduced quasi‐saturation effect over the conventional VDMOS structure. Taking into account all the appropriate physical mechanisms, the analysis self‐consistently solves Poisson's equation, the electron continuity equation and the heat flow equation. The results show that the trench structure introduced enables the device to operate at higher current levels due to a favorable change in current density distribution within the device. However, these two effects can increase the self‐heating of the device, decrease the forward current and degrade the thermal stability of the new structure. Nevertheless the new device is still found to provide a higher quasi‐saturation current than the conventional VDMOS device even when thermal effects are taken into account.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 13 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 February 1995

P.A. Mawby, J. Zeng and K. Board

Poisson’s equation and the electron continuity equation, together withheat flow equation are solved self‐consistently to obtain the latticetemperature profile under…

Abstract

Poisson’s equation and the electron continuity equation, together with heat flow equation are solved self‐consistently to obtain the lattice temperature profile under non‐isothermal conditions in a power VDMOS transistor. The effect of the variable lattice temperature on the forward characteristics of VDMOSTs is presented, and discussed. The results show that self‐heating in power VDMOSTs has a significant effect. The thermal coupling effects on the forward I—V characteristics are compared and discussed between the power VDMOST and the conventional MOSFET.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 5 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 1 April 1992

K. BOARD and P.A. MAWBY

The insulated gate bipolar transistor (IGBT) is an increasingly used power transistor which has the advantage over the more conventional DMOS structure of achieving a

Abstract

The insulated gate bipolar transistor (IGBT) is an increasingly used power transistor which has the advantage over the more conventional DMOS structure of achieving a lower on‐resistance through the high‐injection of electrons and holes into the drift region thereby causing conductivity modulation and a lowering of the electrical resistance.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 2 no. 4
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 3 February 2020

Krzysztof Górecki and Paweł Górecki

The purpose of this paper is to propose a simple electrothermal model of GaN Schottky diodes, and its usefulness for circuit-level electrothermal simulation of…

Abstract

Purpose

The purpose of this paper is to propose a simple electrothermal model of GaN Schottky diodes, and its usefulness for circuit-level electrothermal simulation of laboratory-made devices is proved.

Design/methodology/approach

The compact electrothermal model of this device has the form of a subcircuit for simulation program with integrated circuit emphasis. This model takes into account influence of a change in ambient temperature in a wide range as well as influence of self-heating phenomena on dc characteristics of laboratory-made GaN Schottky diodes. The method of model parameters estimation is described.

Findings

It is shown that temperature influences fewer characteristics of GaN Schottky diodes than classical silicon diodes. The discussed model accurately describes properties of laboratory made GaN Schottky diodes. Additionally, the measured and computed characteristics of these diodes are shown and discussed.

Research limitations/implications

The presented model together with the results of measurements and computations is dedicated only to laboratory-made GaN Schottky diodes.

Originality/value

The presented investigations show that characteristics of laboratory-made GaN Schottky diodes visibly change with temperature. These changes can be correctly estimated using the compact electrothermal model proposed in this paper. The correctness of this model is proved for four structures of such diodes characterised by different values of structure area and a different assembly process.

Details

Microelectronics International, vol. 37 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 7 August 2017

Krzysztof Górecki and Paweł Górecki

This paper aims to propose the electrothermal dynamic model of the insulated gate bipolar transistors (IGBT) for SPICE.

Abstract

Purpose

This paper aims to propose the electrothermal dynamic model of the insulated gate bipolar transistors (IGBT) for SPICE.

Design/methodology/approach

The electrothermal model of this device (IGBT), which takes into account both electrical and thermal phenomena, is described. Particularly, the sub-threshold operation of this device is considered and electrical, and thermal inertia of this device is taken into account. Attention was focused on the influence of electrical and thermal inertia on waveforms of terminal voltages of the considered transistor operating in the switching circuit and on waveforms of the internal temperature of this device.

Findings

The correctness of the presented model is verified experimentally and a good agreement of the calculated and measured electrical and thermal characteristics of the considered device is obtained.

Research limitations/implications

The presented model can be used for different types of IGBT, but it is dedicated for SPICE software only.

Originality/value

The form of the worked out model is presented and the results of experimental verification of this model are shown.

Details

Microelectronics International, vol. 34 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 22 October 2019

Yuri Merizalde, Luis Hernández-Callejo, Oscar Duque-Pérez and Víctor Alonso-Gómez

Despite the wide dissemination and application of current signature analysis (CSA) in general industry, CSA is not commonly used in the wind industry, where the use of…

Abstract

Purpose

Despite the wide dissemination and application of current signature analysis (CSA) in general industry, CSA is not commonly used in the wind industry, where the use of vibration signals predominates. Therefore, the purpose of this paper is to review the use of generator CSA (GCSA) in the online fault detection and diagnosis of wind turbines (WTs).

Design/methodology/approach

This is a bibliographical investigation in which the use of GCSA for the maintenance of WTs is analyzed. A section is dedicated to each of the main components, including the theoretical foundations on which GCSA is based and the methodology, mathematical models and signal processing techniques used by the proposals that exist on this topic.

Findings

The lack of appropriate technology and mathematical models, as well as the difficulty involved in performing actual studies in the field and the lack of research projects, has prevented the expansion of the use of GCSA for fault detection of other WT components. This research area has yet to be explored, and the existing investigations mainly focus on the gearbox and the doubly fed induction generator; however, modern signal treatment and artificial intelligence techniques could offer new opportunities in this field.

Originality/value

Although literature on the use of GCSA for the detection and diagnosis of faults in WTs has been published, these papers address specific applications for each of the WT components, especially gearboxes and generators. For this reason, the main contribution of this study is providing a comprehensive vision for the use of GCSA in the maintenance of WTs.

Details

Journal of Quality in Maintenance Engineering, vol. 26 no. 3
Type: Research Article
ISSN: 1355-2511

Keywords

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Article
Publication date: 10 June 2021

Zhenyu Tang, Xiaoyan Tang, Shi Pu, Yimeng Zhang, Hang Zhang, Yuming Zhang and Song Bo

To use the 4H-SiC material in integrated circuits for high temperature application, an accurate and simple circuit model of n-channel planar 4H-SiC MOSFET is required.

Abstract

Purpose

To use the 4H-SiC material in integrated circuits for high temperature application, an accurate and simple circuit model of n-channel planar 4H-SiC MOSFET is required.

Design/methodology/approach

In this paper, a SPICE model of n-channel planar 4H-SiC MOSFET was built based on the device simulation results and measurement results. Firstly, a device model was simulated with Sentaurus TCAD, with measured parameters from fabricated planar 4H-SiC MOSFET previously. Then the device simulation results were analyzed and parameters for SPICE models were extracted. With these parameters, an accurate SPICE model was built and simulated.

Findings

The SPICE model exhibits the same performance as the measured results with different environment temperatures. The simulation results indicate that the maximum fitting error is 0.22 mA (7.33% approximately) at 200 °C. A common-source amplifier with this model is also simulated and the simulated gain is stable at different environment temperatures.

Originality/value

This paper provides a reliable modeling method for n-Channel Planar 4H-SiC MOSFET and reference value for the design of 4H-SiC high temperature integrated circuit.

Details

Circuit World, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0305-6120

Keywords

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Article
Publication date: 1 April 2005

Jaroslav Mackerle

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming…

Abstract

Purpose

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.

Design/methodology/approach

The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.

Findings

Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Originality/value

This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.

Details

Engineering Computations, vol. 22 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

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