By Topic

Industrial Electronics, 1998. Proceedings. ISIE '98. IEEE International Symposium on

Date 7-10 July 1998

Go

Filter Results

Displaying Results 1 - 25 of 76
  • IEEE International Symposium on Industrial Electronics [front matter]

    Page(s): 0_2
    Save to Project icon | Request Permissions | PDF file iconPDF (29 KB)  
    Freely Available from IEEE
  • Contents

    Page(s): v - xvii
    Save to Project icon | Request Permissions | PDF file iconPDF (950 KB)  
    Freely Available from IEEE
  • Author's index

    Page(s): 0_4 - 0_7
    Save to Project icon | Request Permissions | PDF file iconPDF (162 KB)  
    Freely Available from IEEE
  • An alternative Chua's circuit implementation

    Page(s): 441 - 444 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (268 KB)  

    This paper proposes a novel nonlinear smooth function to implement the Chua's circuit. This new function provides a similar smoothness as to the cubic polynomial function, but a faster response and a simpler circuitry can be obtained. Some bifurcation phenomena and the chaotic attractors are observed experimentally from a practical circuit point of view View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis of real-time data transmission in the DLL of IEC/ISA fieldbus

    Page(s): 694 - 699 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (620 KB)  

    Fieldbus provides real-time data communication among field devices in process control and factory automation systems. IEC and ISA recently approved the Committee Draft of the data link layer of fieldbus standard for use in industrial control systems. The data link layer of IEC/ISA fieldbus is operated on the basis of token-passing and scheduling mechanisms. In this paper, the authors analyze the performance characteristics of the IEC/ISA fieldbus, especially the capability of real-time data transmission. A discrete-event simulation model of the data link layer is developed. Using the simulation model, this paper identifies the network parameters that influence the performance of priority mechanism and real-time data transmission, and analyzes the delay performance of IEC/ISA fieldbus with respect to the change of the network parameters. The fieldbus simulation model also integrates a continuous-time simulation model of a control system as an application process. Using the simulation model, this paper investigates the effect of network-induced delay on the performance of a control system View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A digital integrated circuit for switching of parallel connected converters

    Page(s): 363 - 366 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (272 KB)  

    This paper presents the design of a digital integrated circuit (IC) capable of generating PWM control signals for up to four switching DC/DC power converters. For parallel multi-converter applications, the circuit implements the synchronized voltage mode control. The use of the circuit for controlling a power supply system consisting of four parallel connected buck power converters is described View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Implementation of a zero average current error control algorithm for inverters using a digital signal processor

    Page(s): 450 - 455 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (536 KB)  

    Inverter performance is typically measured against its ability to produce a high fidelity output waveform with narrow band switching frequency and fast transient response. The implementation of a new and improved algorithm that belongs to the family of zero average current error (ZACE) methods is reported in this paper. Advantages include microprocessor implementation, efficient computation with decreased computational intensity and software control of operational parameters (such as switching frequency, output frequency and output amplitude). The effectiveness of the new current control algorithm is demonstrated using an experimental concept prototype View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Use of neural networks in policing bursty traffic sources in broadband ISDN ATM networks

    Page(s): 411 - 414 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (252 KB)  

    The paper discusses the possibility of using artificial neural networks to effectively police the user traffic irrespective of its nature in broadband ISDN ATM networks. A multilayer neural network is used to control the user's traffic parameters within their declared values in order to protect the network's resources. This is achieved by actually employing two neural networks in parallel. One is trained to learn (memorise) the characteristics of a compliant source, whereas the other is used to accurately estimate the characteristics (PDF) of the actual offered user traffic. The two are compared and in case of any incompliance an error signal is generated and the user forced to reduce or modify its traffic generation pattern or else risk some of its cells (violating) being discarded. The paper discusses the possible use of neural networks in policing user traffic in broadband ATM networks View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Automation philosophy of a hybrid plant

    Page(s): 628 - 633 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (532 KB)  

    A 4 layered philosophy compatible with industry standards such as ISA-S88.01, IEC1131 and ISO9001-3 has been applied throughout in automating an AECI Bioproducts Lysine plant with batch, semi-continuous and continuous sections. This paper outlines pertinent aspects of the process of creating robust, maintainable automation software View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An alternative solution for the implementation of configurable interfaces oriented to microprocessor-based control systems

    Page(s): 643 - 647 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (528 KB)  

    The aim of this paper is to present an alternative solution for the rapid prototyping and implementation of configurable interfaces oriented to microprocessor-based control systems. To accomplish this, a wide library of tested macrofunctions that allows the configuration of FPGA devices has been developed. Using this library, the implementation of a number of suitable interfaces compatible with microprocessors, microcontrollers and DSPs of different manufacturers is possible. The design of the interfaces and the configuration of the FPGAs is carried out by means of commercial CAD tools in a short period of time View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimal ordering method for coupling point production control system

    Page(s): 568 - 572 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (464 KB)  

    In the coupling point production system (CPPS), inventories are concentrated at the position where supply lead time and demand lead time are equal. Inventory and production planning are made at this position. This position is defined as the “coupling point” (CP). In a CPPS, different products may have the same coupling point on the same production line. The authors propose an optimal ordering method (OOM for CPPS) to prevent running out of stock and to limit re-order quantities. This new method has been applied to a window frame manufacturing process successfully View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Scheduling of cogeneration facilities operating under the real-time pricing agreement

    Page(s): 390 - 395 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (648 KB)  

    South Africa's largest electricity supply industry (ESI), Eskom, has introduced a pilot project aimed at developing and introducing a real-time pricing (RTP) tariff to its customers. The potential electricity cost savings that this tariff will have on the cogeneration industry is modelled. The purpose of this study is to add more insight into the basic concepts surrounding the scheduling of cogeneration. The system configuration is discussed and simplified. The schematic model configuration show the model's input-output characteristics. The model consists of an energy and cost fraction section. After modelling the generation and steam shifting operations, the cost of electrical energy due to the implementation of the RTP tariff structure is calculated from the model. This cost is compared with the cost of energy after optimal Nightsave (Eskom's two-part demand and energy tariff) scheduling is carried out. The advantages that the RTP tariff holds for industries with cogeneration facilities is also discussed View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Face recognition in a heterogeneous population

    Page(s): 594 - 599 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (752 KB)  

    Face recognition technology has many and varied applications, ranging from document verification to crowd surveillance. The use of face recognition technology in access control is, due to its nonintrusive nature, extremely promising. Most face location and segmentation algorithms proposed in the literature have very limited capabilities, with most not able to find a face which is either rotated or scaled. A novel segmentation algorithm which attempts to overcome these restrictions was developed and used in this study. The Eigenface approach (Karhunen-Loeve transform) has been shown to work extremely well when used to extract feature vectors from a face image. It was found to be the most promising of all the published methods and was therefore used. Most face recognition papers in the open literature have generally used Caucasian faces to test their algorithms, no special mention is made of the other population groups. The effect of a heterogeneous population on face recognition is therefore something of an unknown quantity. It is the aim of this paper to investigate the performance of the developed face recognition system, with emphasis on the effect of a heterogeneous population View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Genetic algorithm approach to production ordering problems with inconsistent constraints

    Page(s): 703 - 708 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (424 KB)  

    A method for solving a scheduling problem with many complicated constraints is proposed. For a case study of such problems, the authors deal with an optimal production ordering problem in the acid rinsing process of a steelmaking plant. Strong requirements assigned to the constraints usually deteriorate the objective value, and in many cases it is impossible to satisfy all the constraints completely. Therefore, fundamental constraints of the problem are treated as hard constraints, the other constraints as soft or relaxable constraints. The genetic algorithm is applied to this problem. A two-phase method is proposed in such a way that: in Phase 1, relaxable constraints conflicting strongly with the objective function are found; and in Phase 2, the Pareto optimal solutions for representing the tradeoff between the objective value and the relaxation of the constraints are obtained. This method is effective because the computation load for tuning penalty parameters is decreased. Furthermore, the method gives a better result than the real operation data View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Power converter analysis and design using Matlab: a transfer function approach

    Page(s): 552 - 557 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (524 KB)  

    The design and steady-state analysis of static power converters has usually been realized in the time domain. This approach however is subject to numerical convergence problems and long simulation times, which worsen as the converter's switching frequency increases. This paper proposes a novel design and steady-state analysis method to overcome these problems using Matlab. The method is based on the Fourier transform (FT) and a generalized converter transfer function. Thus obtains steady-state results without requiring the transient power-up, neither the circuit components' initial conditions. The FT and converter transfer function are used to model and solve the converter in the frequency domain. Desired variables are then obtained in the time domain using the inverse FT. The method eliminates numerical problems and reduces simulation times significantly. For example, the simulation of a PWM voltage source inverter operating at 5 kHz takes 320 times longer in PSpice than in the proposed method. It also presents a minor processing time dependency from the converter's switching frequency. The paper includes a detailed presentation of the proposed method, a complete analysis example using Matlab 4.02, together with an evaluation comparing it to conventional simulating techniques. Finally, experimental results with a 10 kVA AC motor drive are presented to validate the proposed analysis and design method View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A practical control of a cost reduced single phase to three phase converter

    Page(s): 445 - 449 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (352 KB)  

    This paper describes the investigation into the performance of a voltage regulated, cost-reduced single-phase to three-phase power converter. A detailed control strategy to regulate the DC bus voltage is explained. The DC bus voltage is regulated by controlling the phase shift angle δ between the supply, and the inverter. The regulation of a DC bus voltage method of the proposed converter was implemented using digital signal processor. The DC bus voltage was kept constant whilst maintaining the inverter as a balanced static VAr compensator. The dynamic performance of the inverter was shown under two conditions, namely: (1) variation of the load over a specific range; and (2) variation of the input voltage with the load kept constant. The results obtained for each condition show that constant DC bus voltage and AC regulation is achieved View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bare shaft testing of rotating DC electrical machines using digital measurements and optimisation techniques

    Page(s): 653 - 656 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (288 KB)  

    With the recent improvements in digital measurement techniques and modelling of electrical machines, researchers have focused on the possibility of commissioning, testing and condition monitoring AC electrical machines. Papers appeared in the literature from the mid 1980s. More recently, in the 1990s, interest has arisen for the bare-shaft testing of electrical machines. Most of the work reported has been in connection with induction machines. However, DC machines are a strong market contender, especially for low-voltage, mobile applications. In this paper, work is reported on DC machines, where a system for bare shaft testing has been developed. The theory used is explained and demonstrated by simulation. The paper concludes on the usefulness of the method and indicates areas for future work View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Genetic algorithms applied to controller design of an electric drive system

    Page(s): 579 - 583 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (372 KB)  

    Classical control methods are still employed in industry. Proper design and tuning of the controllers are essential for the acceptable performance of the controlled system. In the past, a considerable number of methods have been developed for this purpose. This paper presents a novel, alternative technique of controller design based on genetic algorithms and a laboratory-scale direct current drive as application example. Experimental results show the potential of the method View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Parameter identification of induction motors using DC step excitation at standstill

    Page(s): 468 - 471 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (300 KB)  

    The work deals with a method to identify the electrical parameters of a three-phase-squirrel-cage induction-motor. The identification of the electrical parameters is based on analysis of the stator current motor response to a DC step input voltage applied to the stator windings. In this case, an analytical motor model for DC excitation is developed to produce the theoretical dynamic response function. A numerical interpolation method based on the Gauss-Newton interpolation algorithm, is employed to obtain the values of the motor electrical parameters from the digitized current step response and from the theoretical response function. The validation of the method and parameters is performed by comparing simulated and real data of the free acceleration response View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis of a power conditioning system for superconducting magnetic energy storage (SMES)

    Page(s): 546 - 551 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (512 KB)  

    A power conditioning system (PCS) which can be utilized for the compensation of nonlinear and pulsating loads is analyzed in this paper. The PCS consists of a voltage source inverter and a DC current chopper, and uses a SMES as its energy storage device. The whole system is controlled by three regulators acting on the superconducting coil stored energy, the DC-link voltage, and the inverter AC currents. Numerical simulations have been carried out by PSpice to verify the performance of the PCS in different operating conditions View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the design and experimentation of a ZVS PWM 1.5 kW DC-to-DC converter with half of the input voltage across the switches

    Page(s): 611 - 616 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (452 KB)  

    This paper introduces a new three-level DC-to-DC converter which features half of the input voltage across the switches, zero-voltage-switching, operation at constant frequency, regulation by pulse-width-modulation, and low RMS current stress upon power switches. Analysis, practical design considerations and experimental results of a 1.5 kW converter with 60 V, 25 A output, 600 V input, operating at 50 kHz switching frequency are presented and discussed in the paper View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Chaos-based spread spectrum communication systems

    Page(s): 430 - 435 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (452 KB)  

    A new scheme is proposed for spread spectrum communication which modulates directly both analog data and binary data sequences via chaotic carriers. The proposed systems have some standard properties of spread spectrum communication. Computer simulations and performance analysis are given to examine the validity of this scheme View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Utilising a LonWorks control network for factory communication to improve overall equipment effectiveness

    Page(s): 684 - 689 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (620 KB)  

    Overall equipment effectiveness (OEE) enables factories to increase the output of their products and to minimise the number of rejects. This ensures more competitive products. There are a number of software tools that can be implemented to determine and optimise the overall equipment effectiveness of a plant and increase its productivity. One of the biggest problems when using OEE software is to get the machine data reliably into a compatible OEE database. Dedicated sensor wiring and data acquisition devices are needed to retrieve the data and convert it to a database format. Data retrieval systems that depend on dedicated communication wiring are not flexible enough to be used in manufacturing and packaging lines that consist of moveable components. This paper briefly discusses how OEE is computed and how LonWorks networks can be implemented to retrieve machine data and convert it to a computer database that is used by OEE software tools. It shows the flexibility of LonWorks control network and how it can be used to eliminate unnecessary wiring, by utilising existing power lines as a communication medium View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • New approach to medium voltage variable speed drives

    Page(s): 373 - 379 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (540 KB)  

    This paper outlines the approach taken in the development of a new medium voltage variable frequency drive. It examines the existing medium voltage drive formats, their advantages and disadvantages. It also outlines new standards implemented overseas to limit the effect of harmonics on the electricity supply system, and how these limits impacted on the design of the new generation VSDs. It further examines the effect that advances in microprocessors and electronic power devices has had in the design of the new drive topology View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Alternating noise canceling method of equi-status normal mode noise for encoder

    Page(s): 402 - 406 vol.2
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (304 KB)  

    One of the significant and difficult problems in engineering is the cancellation of equi-status normal mode noises (NMNs). The authors previously proposed an alternating noise canceling (ANC) method for removing NMNs even in the presence of the equi-status noise in instrumentation since 1990. As an example, they made two signals as a sensor output and its opposite output signal by alternating the switching. The sensor output includes the true signal and its opposite output signal and noise from the electromagnetic environment. The data processing of the two signals made a reliable signal without any noise on the transmission line. In this case, “any noise” means normal mode noise (NMN) under a quarter frequency of switching. In this paper, the authors discuss a canceling method of equi-status NMNs in instrumentation by a rotary encoder based on the ANC method. They conduct experiments and verify that this method prevents the miscounting of the instrumentation. Naturally, this method also works even if the power spectra between the signal and NMNs are not different i.e. equi-status NMNs View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.