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Article
Publication date: 17 September 2018

Imen Nouira El Badsi, Bassem El Badsi and Ahmed Masmoudi

This paper aims to investigate the performance of two novel direct torque control (DTC) schemes dedicated to three-switch three-phase inverter (B3-VSI), also called delta…

Abstract

Purpose

This paper aims to investigate the performance of two novel direct torque control (DTC) schemes dedicated to three-switch three-phase inverter (B3-VSI), also called delta inverter, fed induction motor (IM) drives.

Design/methodology/approach

The principle of operation of the B3-VSI-fed IM drive is recalled in a first step. Then, the basis of both proposed DTC strategies is presented. The first DTC scheme considers a subdivision of the stationary plane into three sectors and the application of the intrinsic as well as virtual voltage vectors to achieve the control combinations. While, the second DTC scheme considers a subdivision of the stationary plane into six sectors and a limitation of the voltage vectors incorporated in the look-up table to the three intrinsic ones.

Findings

Simulation and experimental results have revealed that, under steady-state operation and transient conditions, the harmonic content of the IM stator phase currents is lower in the case of the DTC2 strategy, resulting in a lower ripple of electromagnetic torque. Furthermore, it has led to a quasi-circular shape of the locus described by the stator flux vector in the stationary plane.

Research limitations/implications

This work should be extended to the synthesis and performance analysis of a new DTC strategy for B3-VSI-fed IM drive, which emulates the operation of the conventional six-switch three-phase inverter-fed IM drive.

Originality/value

The limitation associated with the reduced number of the intrinsic voltage vectors generated by the B3-VSI has been eradicated, thanks to the suitable synthesis of the look-up table incorporated in the DTC scheme.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 37 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

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Article
Publication date: 1 October 1998

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Industrial Lubrication and Tribology, vol. 50 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 March 1981

John Diffenbach

Your company may find itself traveling down several different paths at once to reach its goals. The secret of success lies in making sure the roads are compatible. At one…

Abstract

Your company may find itself traveling down several different paths at once to reach its goals. The secret of success lies in making sure the roads are compatible. At one time, selecting the right options was a matter of chance. Today, finding the winning combination is almost a science.

Details

Journal of Business Strategy, vol. 2 no. 2
Type: Research Article
ISSN: 0275-6668

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Article
Publication date: 1 January 1988

Nathan IDA

Problem 2 of the International Workshop for Eddy Current Code Comparison is a hollow cylinder with its axis perpendicular to a uniform sinuosoidal field. A total of 10…

Abstract

Problem 2 of the International Workshop for Eddy Current Code Comparison is a hollow cylinder with its axis perpendicular to a uniform sinuosoidal field. A total of 10 solutions, employing 9 different computer codes, are described and compared with analytic results. Most codes were 2‐D finite element and were found to give satisfactory solutions.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 7 no. 1/2
Type: Research Article
ISSN: 0332-1649

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Book part
Publication date: 21 October 2020

Oderlene Vieira de Oliveira, Sérgio Seabra da Silveira Filho and Felipe Alexandre de Lima

The purpose of this chapter is to analyze the reflection of corruption in Brazilian companies listed on Brasil, Bolsa, Balcão (B3). The methodological design comprised a…

Abstract

The purpose of this chapter is to analyze the reflection of corruption in Brazilian companies listed on Brasil, Bolsa, Balcão (B3). The methodological design comprised a qualitative and descriptive approach in which documentary research was used to gather data. Content analysis was employed to treat data retrieved from Standard Financial Statements, Explanatory Notes, and Sustainability Reports, from 2013 to 2017. The findings reveal a low level of disclosure of the companies listed on B3 concerning the reflections of corruption. The disclosed reflections include the increase in the company's operating costs and the impact on the company's future cash flow which can be direct, such as through the reduction of revenues from canceled negotiations, or indirect, through transaction costs due to the misconduct of the company.

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Article
Publication date: 1 March 2002

K.G.B. Bakewell

Compiled by K.G.B. Bakewell covering the following journals published by Emerald: Facilities Volumes 8‐19; Journal of Property Investment & Finance Volumes 8‐19; Property…

Abstract

Compiled by K.G.B. Bakewell covering the following journals published by Emerald: Facilities Volumes 8‐19; Journal of Property Investment & Finance Volumes 8‐19; Property Management Volumes 8‐19; Structural Survey Volumes 8‐19.

Details

Property Management, vol. 20 no. 3
Type: Research Article
ISSN: 0263-7472

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Article
Publication date: 1 March 2003

K.G.B. Bakewell

Compiled by Indexing Specialists (UK) Ltd covering the following journals published by Emerald:Facilities Volumes 8‐20; Journal of Property Investment & Finance Volumes…

Abstract

Compiled by Indexing Specialists (UK) Ltd covering the following journals published by Emerald: Facilities Volumes 8‐20; Journal of Property Investment & Finance Volumes 8‐20; Property Management Volumes 8‐20; Structural Survey Volumes 8‐20.

Details

Property Management, vol. 21 no. 3
Type: Research Article
ISSN: 0263-7472

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Article
Publication date: 25 January 2019

Davood Toghraie, Ramin Mashayekhi, Hossein Arasteh, Salman Sheykhi, Mohammadreza Niknejadi and Ali J. Chamkha

This is a 3D numerical study of convective heat transfer through a micro concentric annulus governing non-uniform heat flux boundary conditions employing water-Al2O3

Abstract

Purpose

This is a 3D numerical study of convective heat transfer through a micro concentric annulus governing non-uniform heat flux boundary conditions employing water-Al2O3 nanofluid. The nanofluid is modeled using two-phase mixture model, as it has a good agreement to experimental results.

Design/methodology/approach

Half of the inner pipe surface area of the annulus section of a double pipe heat exchanger is exposed to a constant heat flux which two models are considered to divide the exposing surface area to smaller ones considering the fact that in all cases half of the inner pipe surface area has to be exposed to the heat flux: in model (A), the exposing surface area is divided radially to two parts (A1), four parts (A2) and eight parts (A3) by covering the whole length of the annulus and in model (B) the exposing surface area is divided axially to two parts (B1), four parts (B2) and eight parts (B3) by covering half of the annulus radially.

Findings

The results reveal that model (B) leads to higher Nusselt numbers compared to model (A); however, at Reynolds number 10, model (A3) exceeds model (B3). The average Nusselt number is increased up to 142 and 83 per cent at models (A3) with Reynolds number 10 and model (B3) with Reynolds number 1000, respectively.

Originality/value

This paper is a two-phase investigation of water-Al2O3 nanofluid in a micro concentric annulus under non-uniform heat flux boundary conditions.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 1 June 1992

U.S. Mishra and M.C. Shukla

This paper deals with the synthesis of water soluble electrodepositable epoxy resins from maleopimaric acid and epoxy resin. Water soluble methylated urea formaldehyde…

Abstract

This paper deals with the synthesis of water soluble electrodepositable epoxy resins from maleopimaric acid and epoxy resin. Water soluble methylated urea formaldehyde resin and melamine formaldehyde resin were also synthesised for curing purposes. The coating compositions were prepared from water soluble epoxy resins, water soluble MF resin, water soluble UF resin, red oxide of iron and zinc phosphate. Thereafter the optimum conditions for electrodeposition were determined in terms of voltage, time, solid contents, pH and bath temperature. These anodic electrocoatings had good film properties such as scratch hardness, flexibility, impact resistance and resistance to water, acid, alkali and solvent.

Details

Pigment & Resin Technology, vol. 21 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 May 2002

K.G.B. Bakewell

Compiled by K.G.B. Bakewell covering the following journals published by Emerald: Facilities Volumes 8‐19; Journal of Property Investment & Finance Volumes 8‐19; Property…

Abstract

Compiled by K.G.B. Bakewell covering the following journals published by Emerald: Facilities Volumes 8‐19; Journal of Property Investment & Finance Volumes 8‐19; Property Management Volumes 8‐19; Structural Survey Volumes 8‐19.

Details

Journal of Property Investment & Finance, vol. 20 no. 5
Type: Research Article
ISSN: 1463-578X

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