By Topic

Electric Power Applications, IEE Proceedings B

Issue 2 • Date March 1981

Filter Results

Displaying Results 1 - 7 of 7
  • Electrification of the Tyne and Wear Metro

    Page(s): 81 - 91
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1411 KB)  

    The Tyne and Wear Metro is the backbone of an integrated public transport system for Tyneside. The paper examines the background to the Metro, the power supply and overhead line equipment, and deals with the general technical considerations which have governed the design of the power system and equipment. Methods of constructions are also discussed, together with the control and operation of the system. Conclusions are drawn in the light of practical experience of the sections of Metro which are now operational. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Attenuation effects of under-track reinforcing on automatic train protection signalling systems

    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (932 KB)  

    The aggregate of steel reinforcement in the concrete plinths and track bed of a particular masstransit railway is found topresent an attenuating environment to the ATP (automatic train protection) signalling system. An attempt is made to investigate the problem via two-dimensional field theory by solving Laplace's equation for the magnetic vector potential. The distributed AC parameters of the secondary circuits formed unintentionally near the track are established. The attenuation of the ATP signals in the presence of steel reinforcement is evaluated for various conditions and is found to be in good agreement with measurements carried out with life-size circuits. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Dedicated-microprocessor scheme for thyristor phase control of multiphase convertors

    Page(s): 101 - 108
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1180 KB)  

    A general-purpose dedicated-microprocessor firing controller scheme is proposed for multiphase thyristor convertors suitable for interfacing with microprocessor-based control systems. It can be described basically as an asynchronous equidistant firing scheme having fast response and including provisions for limit checks and nonlinearity compensation. The hardware and software organisation of an experimental prototype built around the M6800 family of components is elaborated and the performance is verified. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Predicting the pullout torque/speed curve of variable-reluctance stepping motors

    Page(s): 109 - 113
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (561 KB)  

    An efficient numerical technique for predicting the pullout torque of variable-reluctance (VR) stepping motors is described. The method takes account of magnetic saturation and of nonlinearities in the drive circuit, and thus permits reliable prediction of the torque/speed curve to be achieved at the design stage. This is particularly valuable in studying the behaviour at high stepping rates where, hitherto, the influence of the motor and drive parameters has not been properly understood. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Dynamic response of a power-transformer winding under axial short-circuit conditions

    Page(s): 114 - 118
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (589 KB)  

    A model for the dynamic response of a vertical transformer winding, considered as a continuous elastic solid, which produces a partial differential equation, is developed. This model is proposed as a simple means by which some of the many design requirements of large power transformers can be examined. An example is considered and initial and boundary conditions for the partial differential equation are obtained. Various numerical methods of solution are suggested and the computed solution is validated by comparing them with results obtained by other methods. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Effects of 3rd-harmonic voltage content on dielectric losses of solid insulating materials

    Page(s): 119 - 125
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (923 KB)  

    Dielectric losses in solid insulating materials subjected to voltages containing 3rd harmonics are studied. By simple theoretical analysis, some curves are obtained showing the behaviour of the ratio between the dielectric losses in the distorted steady state and in a reference sinusoidal steady state, against 3rd-harmonic content. The reference sinusoidal voltage amplitudes were selected in two different ways; namely, such as to have either peak value or effective value equal to those of distorted waveform. Separate effects of harmonic content and of effective value of the applied voltage are shown through the correspondence of every 3rd-harmonic phase angle. Percentage differences between dielectric losses with sinusoidal and nonsinusoidal voltages are calculated in detail. Theoretical results are then shown to be in very good agreement with experimental data obtained in testing some solid dielectric materials. Emphasis is given to the implication of the results in problems of insulation involving thermal instability in EHV plants. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Inverter drive for switched reluctance motor: circuits and component ratings

    Page(s): 126 - 136
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1666 KB)  

    A variable speed drive using a switched-reluctance motor permits a simpler and cheaper inverter than a PWM inverter for an induction motor. The various inverter circuit options are considered for singlewinding and bifilar-wound motors, noting the advantages of the bifilar 4-phase arrangement from the inverter's viewpoint. The inverter design process for a traction drive with a 3:1 constant power range is explained, followed by the calculation of main and commutation component ratings. Experimental results are given for chopping and for two single-pulse speeds. The control electronics are briefly described. View full abstract»

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