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Electric Power Applications, IEE Proceedings B

Issue 5 • Date September 1983

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Displaying Results 1 - 12 of 12
  • Electrification of Taiwan main-line railway from Keelung to Kaohsiung

    Publication Year: 1983 , Page(s): 289 - 301
    Cited by:  Papers (1)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1726 KB)  

    The paper discusses the electrification at 25 kV AC of a heavily used mixed-traffic railway in Taiwan. Descriptions are given of the thyristor-controlled electric locomotives and multiple passenger units, together with the technical considerations used in the design of the power and communication equipments. Extensive tests of system performance are described, and results are summarised of power-system behaviour at fundamental and harmonic frequencies, together with a statistical evaluation of interference into the telecommunication cable system. View full abstract»

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  • Ward-Leonard characteristics from nonlinearly-controlled series-motor drives

    Publication Year: 1983 , Page(s): 302 - 309
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (946 KB)  

    Two methods are explored for improving the manoeuvrability of fork-lift trucks driven by chopper-controlled series motors. The first method attempts nonlinear feedforward cancellation of one system state (speed) but is shown to be unstable by simulation and analytical solution of the system equations. The instability results from neglect of field inductive effects in the feedforward model. A second method employs synthesised torque and transient-velocity estimates derived purely from armature current feedback. The method is shown by simulation to be highly tolerant of uncertainty in the vehicle and drive parameter estimates and to produce overall control characteristics resembling those of Ward-Leonard drives. The manual handling of the truck on a variable-gradient test track shows a considerable improvement on conventional linear current control systems. View full abstract»

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  • Loss-optimal PWM waveforms for variable-speed induction-motor drives

    Publication Year: 1983 , Page(s): 310 - 320
    Cited by:  Papers (5)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (995 KB)  

    The paper calculates and provides results on loss-optimal commutation tables suitable for application in digital PWM commutation steering circuits for variable-speed induction-motor drives. The work differs from other works on this subject, because a special induction-motor-loss model is incorporated into the PWM waveform optimisation procedure, and because optimised waveforms with up to seven commutations per quarter period are provided. View full abstract»

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  • Book review: Power Electronics

    Publication Year: 1983
    Save to Project icon | PDF file iconPDF (121 KB)  
    Freely Available from IEEE
  • A cycloconvertor-linked induction heating system

    Publication Year: 1983 , Page(s): 321 - 330
    Cited by:  Papers (2)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1142 KB)  

    A naturally commutated cycloconvertor-type frequency-changer system operating in the inverting mode has been used for the first time for the induction heating of metals, thus dispensing with the usual DC link. The proposed scheme has been mathematically analysed. Control schemes have been devised and are experimentally verified. The induction heating system based on this new concept has a number of advantages over the existing induction heating systems and has very good scope for commercial exploitation. View full abstract»

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  • Equivalent rotor impedance of sheet-rotor induction motors

    Publication Year: 1983 , Page(s): 331 - 340
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (910 KB)  

    A theory is developed which allows the equivalent resistance and reactance of sheet rotors of various geometrical configurations to be determined. Two factors are presented which relate the resistance to that of a simple rotor with zero-resistance end rings and the reactance to the magnetising reactance. The analysis assumes a sinusoidal travelling current-density wave at the stator surface but the treatment of winding harmonics is indicated. The most common forms of sheet rotor are considered as special cases. Experimental evidence is given in support of the findings. View full abstract»

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  • Optimum design of shaded-pole motors by means of 2-phase symmetrical components

    Publication Year: 1983 , Page(s): 341 - 346
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (604 KB)  

    By application of the 2-phase symmetrical components to the shaded-pole motor, which is regarded as an asymmetrical induction motor, equations for calculation of principal characteristics, such as steady-state torque and double-frequency alternating torque, are derived. Based on these equations, the speed characteristics of the double-frequency alternating torque, effects of the parameters on steady-state torque curves and maximum efficiency are discussed. Parameters for many examples of machines are investigated, and it is shown that their parameter ratios are within certain ranges. Optimum values of parameter ratios are obtained by taking into account efficiency, steady-state torque, alternating torque etc. The limit of the shaded-pole motor, i.e. the best possible performance, is discussed. Experimental confirmation of the theory is given. View full abstract»

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  • Active filters for static power convertors

    Publication Year: 1983 , Page(s): 347 - 354
    Cited by:  Papers (12)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1340 KB)  

    The need for output filters with static power convertors is well known. The paper presents a different way of solving the problem. A new configuration is therefore proposed, which includes both active and passive components. The advantages of this system are, among others, that it can be used for both AC and DC convertors, especially where very low distortion is needed at the output. A method for calculating the different components is proposed, and practical results obtained from a prototype are given. The possibility of using such filters with variable-frequency convertors is discussed. View full abstract»

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  • Analysis of commutation of a current-source inverter feeding an induction motor, using 2-axis variables

    Publication Year: 1983 , Page(s): 355 - 359
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (640 KB)  

    Based on a 2-axis model, a closed-form expression is derived for the current during commutation in the outgoing line of a current-source inverter-fed induction motor. The machine parameters and capacitor voltages affect the variation. Using the currents during commutating and noncommutating periods in a one-sixth cycle, the performance of the induction motor is determined. The computed performance is experimentally verified and the equations are found to give satisfactory results. View full abstract»

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  • A polyphase 500 kA current measuring system with Rogowski coils

    Publication Year: 1983 , Page(s): 360 - 363
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (454 KB)  

    A polyphase current measuring system is described. The design parameters are given, followed by theoretical consideration of how they can be met. The practical realisation, as well as some actual results, are given. It is shown that 450 kA peak AC currents with DC components, having time constants up to 250 ms, can be measured within 2% accuracy. The main advantages of this system are the potential-free measurements and the low cost compared to shunt or CT measuring systems. View full abstract»

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  • Analytic separation of the factors contributing to the eddy-current loss in magnetically nonlinear steel

    Publication Year: 1983 , Page(s): 364 - 372
    Cited by:  Papers (2)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (995 KB)  

    Many approximate solutions for eddy-current loss in solid steel have been published, but little attention has been given to identifying the effects of magnetic nonlinearity on the loss and electromagnetic-field distribution. An analytic solution is described in which these effects are identified, and defined by simple factors which are determined from the B/H-curve for the steel; this curve is represented by the function B = aHb. Saturation harmonics are accounted for approximately by the use of the single derived function B1 = AHb1 this is validated by a separate analytic investigation. Comparison with the limiting nonlinear theory, for which B = ±BS, leads to a definition of BS which relates it to the shape of the B/H-curve. An experimental investigation to test the theory is also described. View full abstract»

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  • Corrigendum: Linear induction motor: equivalent circuit model

    Publication Year: 1983
    Save to Project icon | PDF file iconPDF (143 KB)  
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