# Electrical Engineers, Proceedings of the Institution of

## Filter Results

Displaying Results 1 - 21 of 21
• ### Test-point condensation in the diagnosis of digital circuits

Publication Year: 1977, Page(s):89 - 94
Cited by:  Papers (16)
| |PDF (788 KB)

The paper shows how simple circuitry can be used to combine test points leading to far fewer points to be observed, while still retaining the full ability to detect faults. Rules are laid down for the design of this circuitry that depend on the relationship between the test points. Practical examples are given of circuits for condensing test points for a number of different circumstances. Finally,... View full abstract»

• ### Mobile radio propagation in British cities at frequencies in the v.h.f. and u.h.f. bands

Publication Year: 1977
Cited by:  Papers (2)
| |PDF (838 KB)

Measurements of the received signal envelope magnitude have been made in three British cities at frequencies of 85.875, 167.2 and 441.025 MHz. In all cases unmodulated carrier waves were radiated from aerials atop tall buildings, or prominent terrain features, and detected using a vehicle-mounted receiver. These measurements have provided the basis for an analysis of the factors affecting the tran... View full abstract»

• ### Signal transfer and degradation in surface-channel charge-coupled devices

Publication Year: 1977, Page(s):103 - 108
| |PDF (949 KB)

The properties of surface-channel charge-coupled shift registers are analysed taking into account all four mechanisms involved in the transfer of charge, namely thermal diffusion, charge gradient-induced drift, fringing-field drift, and interface state trapping. A nonlinear equation for the simulation of the signal transfer and degradation in charge-coupled shift registers in the presence of inter... View full abstract»

• ### Effects of field-dependent mobility on transfer efficiency in m.o.s. b.b.d. analogue delay lines

Publication Year: 1977, Page(s):109 - 113
| |PDF (612 KB)

The effects of field-dependent mobility on transfer inefficiency due to intrinsic transfer limitations, dynamic-dram conductance and threshold-voltage modulation are calculated for an m.o.s. bucket-brigade delay line. The results show significant differences over previous theories at higher clock frequencies, where line performance is critical if quantisation errors are to be minimised in analogue... View full abstract»

• ### Amplitude fluctuation of underwater signals and its effect on the bit-error probability of underwater data-transmission systems

Publication Year: 1977, Page(s):115 - 119
Cited by:  Papers (2)
| |PDF (671 KB)

Two models are proposed for the probability density function (p.d.f.) of the amplitude fluctuations that arise when short-duration sound pulses are transmitted under shallow-water conditions. The models are derived for the conditions in which the prevailing surface-wind directions are parallel and perpendicular to the line of transmission. The probability density functions obtained from the models... View full abstract»

• ### Erratum: Survey of measurements of attenuation by rain and other hydrometeors

Publication Year: 1977
| |PDF (111 KB)
• ### Analysis of fields and inductances in air-cored and iron-cored synchronous machines

Publication Year: 1977, Page(s):121 - 126
Cited by:  Papers (56)
| |PDF (740 KB)

A consequence of the projected trend in turbine-generator design towards large airgaps, airgap windings without slots, and superconducting windings, is a progressive change in the nature of the machine from iron-coredÂ¿ to air-coredÂ¿. A general analysis of fields and winding inductances that is applicable to all configurations is presented. The underlying unity of the various types is brought o... View full abstract»

• ### Comparative design and performance analysis of air-cored and iron-cored synchronous machines

Publication Year: 1977, Page(s):127 - 132
Cited by:  Papers (24)
| |PDF (882 KB)

A consequence of the projected trend in turbine-generator design towards larger airgaps, airgap windings without slots, and superconducting windings, is a progressive change in the nature of the machine from iron-coredÂ¿ to air-coredÂ¿.A simple analysis is presented which enables the main design and performance paramaters of both types of machine to be calculated and compared. A design philosoph... View full abstract»

• ### Laplace analysis and computer simulation of transient current in power transmission lines

Publication Year: 1977, Page(s):133 - 136
| |PDF (556 KB)

A systematic Laplace method is presented for the determination of transient-current propagation in a single transmission line. Earth distortion and skin effects are considered in the analysis. The method permits a quick and accurate evaluation of these currents without using numerical-integration techniques. From the theoretical study, an efficient method of digital simulation is also derived for ... View full abstract»

• ### Laplace analysis and computer simulation of transient current in power transmission lines Pt, 2-Polyphase systems with lossy earth return

Publication Year: 1977, Page(s):137 - 140
| |PDF (444 KB)

In this study, an operational Laplace method is presented for analysing current propagation in 3-phase lines. Basic results obtained in Part 1(see p. 133)are systematically extended to polyphase-line investigations. Modified operational Laplace impedances are used and results can be carried out by a direct use of Laplace transforms and matrix theory. An efficient simulation method is also presente... View full abstract»

• ### Distance protection performance during simultaneous faults

Publication Year: 1977, Page(s):141 - 146
Cited by:  Papers (5)
| |PDF (717 KB)

The paper considers the performance of both unswitched and switched distance protection schemes using polarised-mho relays on systems subjected to simultaneous faults. The disturbances considered are flashoverfaults to earth, cross-country earth faults and open-conductor plus earth faults on a double-circuit 132 kV transmission system. Consideration is also given to protection performance for doub... View full abstract»

• ### On-site investigation of electrohydraulic governors for water turbines

Publication Year: 1977, Page(s):147 - 153
| |PDF (1052 KB)

Hydroelectric generating sets controlled by conventional, mechanical, temporary-droop governors respond rather slowly to changes in system frequency and do not, therefore, realise their full potential as spinning reserves. Because of this, the electrohydraulic governor system described in this paper was developed for on-site evaluation of control strategies on a 32.5 MW set at Sloy power station, ... View full abstract»

• ### Probabilistic techniques in a.c. load-flow analysis

Publication Year: 1977, Page(s):154 - 160
Cited by:  Papers (48)
| |PDF (683 KB)

The paper describes how the previously published formulations for an a.c. probabilistic load-flow analysis can be extended to ensure precise computation of expected values, and how these may be used to obtain more precise values of standard deviations and probability-density curves than was possible thereto. Both of the present formulations linearise the problem around the precise expected value, ... View full abstract»

• ### Estimation of the states during refining in electric-arc-furnace steelmaking

Publication Year: 1977, Page(s):161 - 166
| |PDF (778 KB)

The commercial incentives to obtain improved control of the steelmaking process in the electric-arc furnace are presented, and the progress made in applying computer control is reviewed. The development of a mathematical model of the refining process is shown to be restricted by the complex metallurgical nature of the process and the deficiency of existing plant instrumentation. The ability of a m... View full abstract»

• ### Optimal return difference matrix

Publication Year: 1977, Page(s):167 - 168
Cited by:  Papers (1)
| |PDF (236 KB)

The infinite time LQR optimal control problem is considered, and a relationship is obtained between the optimal return difference matrix and the system matrix. The derivation is based on equivalence of optimal systems and leads to physical interpretation of the result not previously available. View full abstract»

• ### Improvement and prediction of open-loop starting/stopping rates of stepping motors

Publication Year: 1977, Page(s):169 - 172
Cited by:  Papers (3)
| |PDF (573 KB)

The maximum instantaneous starting and stopping rates of stepping motors often restrict applications. Three simple methods of increasing these rates by as much as 300% are described. They apply to any type of motor and merely involve the addition of a cheap and simple circuit between the motor and its normal drive. The start/stop rates for the new techniques are predicted by simple methods which c... View full abstract»

• ### Digital point-on-wave switch for investigating motor starting characteristics

Publication Year: 1977, Page(s):172 - 173
Cited by:  Papers (1)
| |PDF (238 KB)
• ### Effect of corona on the density of ionisation in a highߝvoltage laboratory

Publication Year: 1977, Page(s):174 - 178
Cited by:  Papers (1)
| |PDF (616 KB)

Ion densities in a closed laboratory due to d.c. corona from an impulse-voltage generator and its charging set have been measured by means of a Gerdien-type aspirator. By comparison with natural ionisation, the densities of ions of the same polarity as the generator charging voltage were increased by two orders of magnitude, but ions of opposite sign were greatly reduced in density. Use of a filte... View full abstract»

• ### Computation of axial and radial development of discharges between plane parallel electrodes

Publication Year: 1977, Page(s):179 - 182
Cited by:  Papers (10)
| |PDF (559 KB)

The numerical method for computing the growth of ionisation currents in the presence of space charge has now been extended to cylindrically symmetrical discharges. A full description of the method of calculation is given, together with some preliminary results for the experimental conditions of Doran. The growth of the discharge is computed up to the end of the cathode-directed streamer, and predi... View full abstract»

• ### Optical studies of prebreakdown events in liquid dielectrics

Publication Year: 1977, Page(s):183 - 187
Cited by:  Papers (21)
| |PDF (853 KB)

A combination of time-resolved Schlieren and scattered-light optical techniques has been used to examine the prebreakdown events in dielectric liquids. When a negative high-voltage pulse is applied to the point of a nonuniform gap, a disturbance, associated with discrete shock waves, propagates outwards from the point. For the opposite polarity, the disturbance moves at supersonic velocity, and is... View full abstract»

• ### Unbalanced a.c. bridges for the measurement of dielectric loss

Publication Year: 1977, Page(s):188 - 192
Cited by:  Papers (1)
| |PDF (599 KB)

The ideal a.c. bridge would include a variable conductance standard, but no such component can be made for high frequencies. The need for it can be avoided by working with a slightly unbalanced bridge, in which the unbalanced signal is a measure of the conductance of the specimen. The method is particularly suitable for measurements of dielectric loss, using micrometer-controlled electrodes. There... View full abstract»

## Aims & Scope

The Proceedings of the Institution of Electrical Engineers was published by the IET between 1963 and 1979.

Full Aims & Scope