New Publications are available for Power systems and applications
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New Publications are available now online for this publication.
Please follow the links to view the publication.Web based control and information system
http://dl-live.theiet.org/content/conferences/10.1049/ic_20010045
With the rapid advancement in Internet technology, the application of remote control systems for engineering purposes via the Internet is the theme of the paper, ultimately leading to a cyber learning system. A personal computer that is hosting a Web server is connected to the Internet. Whenever the user performs some action through the GUI (front end) on a web page in a remote PC connected to Internet, the server executes a CGI program that will issue hardware signals through a parallel port/DAQ to perform hardware controls executed by a micro-controller/GPIB. Thus the aim to integrate both information and remote access together to give real-time remote control access via Internet is tested by developing a system with PC, microcontroller/DAQ. The conventional TCP/IP protocol and standard browser interface is used to make it simple and easy. Authentication for access is done through login and password before any control action is performed. Two systems were developed and tested. Experiments on a remotely controlled DC dynamometer using Java Applets and another experiment for utilization of power in household appliances was carried out. This can be further extended and used in distance education systems for practically performing laboratory experiments via Internet, thus eliminating the scheduling and logistical problems when a sixty students classroom needs to perform the experiment with only one experiment setup and limited lab time. (6 pages)Activities and features of the New High Voltage Laboratory at the Ohio State University (USA)
http://dl-live.theiet.org/content/conferences/10.1049/cp_19990554
In the USA, only a handful of high voltage laboratories can be found that are operated by universities. The High Voltage Laboratory at The Ohio State University was designed and constructed in the 1990s. Its major facilities are related to the generation and measurement of high voltage AC, DC and surges. The laboratory has high voltage DC sources (up to 150,000 V), high voltage AC sources (up to 250,000 Vrms), a 1,000,000 V surge generator, and a high voltage Tesla transformer (up to 2.5 MV). Test capabilities include withstand, partial discharge and breakdown tests on gases, liquids and solids, electric and magnetic field tests, reduced-scale model tests, fog chamber tests (accelerated aging) and shielding and attenuation experiments. The laboratory is used for education (teaching high voltage courses and lab sessions), research and independent testing. (4 pages)Discussion on “The functions of the engineer: his education and training”
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1919.0026
Hydro-electric power supply
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1923.0015
The objects of the paper are: (1) To describe briefly the chief constituent parts of a hydro-electric development, and their functions; (2) to discuss some of the economic factors controlling the development and operation of water-power plants; and (3) to consider the question of tidal power where it exemplifies the working of these economic factors.Some researches on the safe use of electricity in coal mines
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1924.0068
The limiting electrical conditions under which ignition of coal dust and firedamp may occur have been worked at in the author's laboratory for the past 14 years, as part of a general investigation of the mechanism of ignition of gases. The paper contains an account of some results of practical interest, and deals with the electrical ignition of coal dust alone, coal dust with gas present, of methane and associated gases by disruptive sparks, steady or impulsive, transient arcs, direct or alternating, with varied voltage and frequency, in all percentages of mixture with air. Examples are given of the application of the results to promote safety in mines, notably the influence of currents of higher frequency than usual, of safety bells, safety lamps which give an alarm signal when dangerous mixtures of gas occur, and an improved earthing plate.Discussion on “High-power fusible cut-outs” before the Institution, 18 March, 1926
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1926.0099
Discussion on “Contact effects between electrodes and dielectrics”
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1929.0083
An ammeter for very high frequencies
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1930.0055
The paper describes the construction and theory of a simple form of hot-wire ammeter intended for use at any frequency up to 100 million cycles per sec. A cylindrical form is adopted in order that the correction factors for various frequencies may be calculated with certainty, and figures are given for an instrument as actually constructed.Storage batteries in relation to modern supply of electric lighting and power
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1928.0042
Discussion on “Some technical considerations concerning power factor in relation to tariffs” before the Meter and Instrument Section, 5th April, 1929
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1929.0143
Discussion on “The steam and electric power plant of Imperial Chemical Industries, Ltd., at Billingham” before the South Midland Centre, at Birmingham, 14th April, 1930
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1930.0146
Corrigendum: Power stations and their equipment
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1932.0063
Discussion on “The electrical high-pressure testing of cables and the localization of faults” before the Meter and Instrument Section, 6th March, 1931
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1931.0107
Discussion on “Note on sheath losses in single-core single-phase cables”
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1929.0084
Discussion on “Electricity in mines” before the North-Western Centre, at Manchester, 3 March, 1925
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1925.0068
Discussion on “Apparatus and methods for accurate maintenance of large a.c. energy meters” before the North Midland Centre, at Leeds, 24th February, 1931
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1931.0066
The author's reply to the discussions on “Some researches on the safe use of electricity in coal mines”
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1924.0076
Discussion on “Some tests and uses of condensers”
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1909.0073
Large electric baking ovens
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1928.0056
Existing types of flame-heated ovens have been examined and described because the successful application of electric baking ovens involves a thorough understanding of the principles of bread-baking and cake-baking.Tests for determining the uniformity of temperature in flame types of ovens are illustrated and summarized, mainly because the electric oven lends itself to greater uniformity of temperature by grading and locating the elements.Constructional details of electric ovens are dealt with as an indication of the suitability of each type for particular locations. Portable and brick-built oven construction is illustrated and explained. British, American and Continental ovens are surveyed.A glossary of terms peculiar to the baking trade has been compiled by the author as no published definitions of the terms have hitherto been available.Operation costs are shown, including maximum-demand averages from more than 100 installations.The demand for the abolition of night baking has a very important bearing on the most suitable type of electric baking oven construction, and the brick-built oven with high heat-storage capacity and high thermal efficiency deserves careful consideration. These ovens are heated during “off peak” periods only.Sphere-gap calibration
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1931.0096
The following report contains an account of experiments carried out at East London College upon spark-over between spheres and the standardization of the sphere-gap as a voltmeter.The origin and objects of the research are described. A detailed account is given of the methods employed in measuring the high voltages, which include the following:—(i) Measurement on primary.(ii) Measurement on secondary tap.(iii) Measurement of current through a high-voltage air condenser.(iv) Use of capacitative potential divider.(v) High-voltage electrostatic voltmeter.(vi) Measurement of frequency and wave-form.The accuracy and convenience of these are discussed.Special apparatus constructed is described, including a high-voltage air condenser and gaps with spheres 62.5 mm and 20mm diam.respectively.A number of experiments on the effect of various conditions upon the spark-over voltage are described.The existing standard recommendations with respect to the proximity of neighbouring objects were confirmed, but it is shown that some of the precautions appear too stringent, whereas some factors particularly the size of earth plate, should be taken into account.It is shown that a strong source of ultra-violet light decreases the spark-over voltage, radiations of wavelength at least less than 3200 Å.U. being necessary. The decrease varies with the intensity of the radiation and does not reach a limit under normal circumstances. Since a weak source of ionization appears adequate for ensuring regularity of results, illumination with ultra-violet light is not recommended, but it is desirable that some degree of initial ionization should be ensured, such as that due to weak corona, although this ionization appears usually to be present without special procedure.The effect of the surface conditions was investigated and found to be very complicated; it is concluded, as in a previous investigation, that a clean polished surface, but not a mirror polish, is desirable.The effect of humidity and different types of contaminated atmospheres was investigated. The effect of humidity alone was a small decrease in spark-over voltage. Smoke of different types produced different effects and varied also according to the humidity. A large decrease of spark-over voltage was produced only by a very thick cloud of smoke. The spark-over voltage was found to be irregular in an atmosphere the humidity of which was changing.The behaviour of spheres of brass, phosphor bronze and mild steel was studied and is compared. In the authors' experiments phosphor bronze was found to be most satisfactory for a number of reasons, but definite consistent differences between the metals were not established.Calibrations are put forward for 20-mm diameter and 62.5-mm diameter spheres up to 80 kV (R.M.S.). The calibrations for 20-mm diameter spheres agree substasntially with those previously put forward as provisional standards by the E.R.A. based on experiments at the British Thomson-Houston C0., Ltd., They also do not show a very great variation from the recent figures adopted by the American Institute of Electrical Engineers. The calibrations for 62.5-mm diameter spheres agree with the revised American I.E.E. figures up to about 50 kV (R.M.S.), but are low compared with the latter for voltages above this figure.The accuracy of the calibrations is discussed and it is concluded that these are limited by the inherent variations of spark-over voltage. It is considered that a probable error up to about 0.5 per cent in a mean of 4 or 5 readings must be admitted for which it has not been found possible satisfactorily to account. Thus the sphere-gap is not considered to be a measuring instrument of the highest grade such as, for example, a standard voltmeter at lower voltages, although it is more reliable than many high-voltge voltmeters at present commonly used in commercial practice.Discussion on “The modern use of pulverized fuel in power stations” before the South Midland Centre, at Birmingham, 2nd December, 1929
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1930.0049
Water penetration effects in lead-sheathed power cables
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1930.0040
The immersion in water of lead-covered cables, with a view to the detection of faults in the lead sheathing, is discussed. Tests of the time taken to show up these defects in power cables at different water pressures are given for various cable samples. The conclusions drawn are that, except possibly in the case of low-voltage cables, no such defects will be discovered during factory routine, and that for high-voltage cables, at least, water immersion should be definitely discontinued.A new method of measuring adsorbed moisture films non-conductors
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1934.0067
A method is described by which the presence of adsorbed moisture on the surface of a solid insulating material in the form of an ellipsoid freely suspended in a closed vessel can be observed and its electrical properties measured.The theory of the instrument is set out, together with a numerical example, and expressions are found for the polarization and conduction currents, and for the resistivity of the film on glazed porcelain. This is of the mean order of 10<sup xmlns="http://pub2web.metastore.ingenta.com/ns/">2</sup> ohms per cm<sup xmlns="http://pub2web.metastore.ingenta.com/ns/">2</sup>. An example is given of the change of the of the film with time.Chemical and physical drying are compared, and a form of electrical hygrometer is described depending on the change of distribution of electric fields on a glazed surface produced by a change in the hygrometric state of the air. By the use of a relay an alarm-bell is rung when a certain hygrometric state is reached.Discussion on “The application of automatic voltage and switch control to electrical distribution systems” before the Mersey and North Wales (Liverpool) Centre, at Liverpool, 20th November, 1933
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1934.0045
Discussion on “Some experiments on single and stranded low-tension fuses”
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1910.0013
The authors' reply to the discussions on “The application of automatic voltage and switch control to electrical distribution systems” at London, Manchester, Liverpool, Newcastle, Bristol and Dublin
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1934.0049
A universal “chart” method of calculating starting rheostats for direct-current motors
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1922.0064
The calculation of the resistances of the sections of a starting rheostat for a series motor requires a knowledge of the magnetization curve of the motor, as well as a determination of two “grading” coefficients (of which one depends on the variation of flux, and the other on the variation of current, during starting). A number of graphical and analytical methods of calculation have been proposed, but these give the solution only for a particular number of sections. The method presented in this paper has the same order of accuracy as analytical methods, but it enables the grading coefficients corresponding to several numbers of sections to be obtained simultaneously from a single set of preliminary calculations, which are considerably simpler than those required with other analytical methods. The basis of the method is the use of charts of grading coefficients which are calculated for various numbers of sections, definite values of the percentage pressure-drop in the motor at full load, and given starting conditions. The grading coefficients for any particular motor are obtained by plotting on the appropriate chart a magnetization characteristic of the motor and determining the intersection of this curve with the appropriate curves on the chart. The complete calculation of a starter can be carried out in a few minutes. The method is particularly suitable for rheostat design departments, as the charts are of universal application. Charts of grading coefficients are given for all practical requirements for industrial control and also for seriesparallel control. A number of worked examples are included, illustrating the application of the method.Discussion on “The medical and surgical applications of electricity” before the South Midland Centre, at Birmingham, 31st March, 1930
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1931.0016
Discussion on “Electro-farming, or the applications of electricity to agriculture” before the Institution, 4 March, 1926
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1926.0079
Discussion on “The steel-melting coreless induction furnace” before the North-Eastern Centre, at Newcastle, 10th April, 1933
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1933.0161
Discussion on “The costing of production at selected stations” before the Scottish Centre, at Edinburgh, 12th December, 1933
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1934.0052
Thermal transference in transformer oils
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1929.0041
The question of thermal transference in transformer oil was brought forward by Mr. W. Pollard Digby in 1915, † and further elaborated in a report of the I.E.E. Research Committee. ‡ Suggestions were there made for an experimental investigation to verify the conclusions reached, and the research reported herein, besides achieving this, has produced further useful information.The cooling power of three transformer oils has been investigated by means of a special apparatus, representing transformer conditions in a simplified form for experimental work.Attention has been given both to the temperature-rise of the oil and to that of the windings. It has been found that classification of oils according to temperature-rise of the fluid does not necessarily yield the same order of merit as classification according to temperature reached by the windings.The physical properties of the oils have been measured, and an attempt has been made to correlate the cooling data with these.It appears that the group of variables (<i xmlns="http://pub2web.metastore.ingenta.com/ns/">ac/v</i>) is important in both cases. Here <i xmlns="http://pub2web.metastore.ingenta.com/ns/">a, c</i> and <i xmlns="http://pub2web.metastore.ingenta.com/ns/">v</i> are respectively the coefficient of expansion of the coil, its specific heat per unit volume, and its kinematical viscosity. The extreme variations of viscosity with temperature limit the precision with which this information can be applied to predict the relative performance of very similar fluids.The temperature-rise of the windings differs from that of the fluid, in that it is influenced by the thermal conductivity of the oil. Further, the influence of the thermal conductivity in this case is probably greater than the influence of the group of properties represented by <i xmlns="http://pub2web.metastore.ingenta.com/ns/">ac/v</i>.The work was carried out, at the National Physical Laboratory, by Messrs. W. F. Higgins and A. H. Davis.The author's reply to the discussions on “Some recent advances in alternating-current measuring instruments” at London and Newcastle
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1927.0061
The production, measurement, and effect of variable wave-form
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1910.0019
Discussion on “The drive of power station auxiliaries” before the North-Western Centre, at Manchester, 20 November, 1923
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1924.0027
The current-carrying capacity of solid bare copper and aluminium conductors
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1924.0119
The current-carrying capacity of bare copper and aluminum conductors is limited by the heating effects produced by the current. The dissipation of this heat is a function of the temperature elevation above the surrounding air, the size of the conductor, and the intrinsic condition of the surface. A cooling-curve method is described which was used in determining the coefficient of heat emissivity for a series of small sample lengths of round and flat copper and aluminium conductors of various sizes and surface conditions. This was checked by the direct electrical heating of longer lengths, which showed the two methods to be in close agreement. Tables for the current-carrying capacity of copper and aluminium busbars have been deduced from the constants obtained and are given in the paper.Recent developments in electricity meters, with particular reference to those for special purposes
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1929.0093
The paper gives a general survey of metering work in this country.Some particulars are given regarding the more usual faults found in service, and the requirements for maintained accuracy are briefly discussed.Various standard types of meters are examined and recent modifications detailed.Methods used for obtaining summated demands and consumption are discussed, together with various types of equipment for special purposes.The development of reactive kVA metering methods is traced and apparatus described. The testing of such apparatus is difficult and calls for a high degree of skill.Finally, a few remarks are made regarding special tariffs and testing procedure.Discussion on “The measurement of X-ray tube current and voltage” before the Institution, 30th March, 1993
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1933.0154
The modern use of pulverized fuel in power stations
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1929.0140
As a result of the experimental work carried out in the Birmingham electric power station, it has been demonstrated that the use of pulverized fuel gives a higher combustion heat efficiency in the boilers than is obtained with mechanical stokers.Boilers having a capacity far greater than those equipped in the past with mechanical stokers can be used, with a consequent reduction in the capital cost of boilers and boiler house; this is a set-off against the higher capital cost of the pulverized-fuel equipment compared with mechanical stokers.The evolution of pulverized-fuel installations is tending towards reduced equipment and greater simplicity in operation; this is effected by eliminating the coal driers and the conveying and storage of the pulverized fuel.The theory of the dynamometer wattmeter
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1910.0021
Future progress in electrical measuring instruments
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1933.0054
Some tests and uses of condensers
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1909.0072
Discussion on “The rotor bearings of electricity meters” before the Meter and Instrument Section, 1st March, 1929
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1929.0133
Discussion on “Electric motor starters” before the South Midland Centre, at Birmingham, 15 March, 1922
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1922.0043
Low-temperature carbonization of fuel, with special reference to its combination with the production of electricity (American practice)
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1930.0015
In this paper consideration is given to the posssibility that the pre-treatment of coal with recovery of by-products may secure and economic advantage in the production of electricity in the United States of America.Reference is made to the trend of opinion in the minds of power station engineers and to the great interest which is maintained in the subject.The economic possibilities are reviewed and stress is laid on the necessity for securing a maximum revenue from the sale of such gas as is produced by the process of pre-treatment, and it is calimed that this result can be obtained only by co-operation with public service companies supplying gas to domestic and industrial concerns.The installation of the McEwen-Runger process at the Lakeside station of Milwaukee Electric Railway and Light Co. is described and an account is given of its development so far as it has been continued in America, the earlier experimental work which originated in England being omitted. Particulars are given of the progress which has been made, together with an indication of the direction which future development will follow.The design of electrical plant, control gear and connections for protection against shock, fire and faults
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1925.0051
The risks to life and plant are set out.Means for prevention are discussed in full and summarized in conclusion.In the main an endeavour has been made to collate present practice and to ventilate some demands which are in a nebulous stage, including the duplication of components, the changing over of live circuits, the meaning of the breaking-capacity rating of circuit breakers, the use and effect of reactances, charging resistances and lightning arresters, and the best means of economy in switchgear without loss of safety.In reviewing known automatic protective systems, stress is laid upon the importance of what has been termed, for the purpose of this paper, the “stability ratio.” Stability takes precedence over sensitivity. In balanced automatic protective systems stability is jeopardized by influences, some of which are of recent discovery and have been brought to light by new conditions of service. They include the unbalancing effect of high-frequency oscillations on main lines, and interference by induction between the main line and the pilot line. Suitable remedies are available and have been applied.The relation of interference with telephone service and fault occurrences on power supply systems provides a further argument in favour of good bonding, earthing the neutral and the instantaneous isolation of faults.Mechanical consideration is given to the layout of switch-gear and to the terminal construction of plant, and a diagrammatic illustration of the alternator main, field, and neutral connections is shown.Discussion on “Electricity in mines” before the North-Eastern Centre, at Newcastle, 8 November, 1926
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1927.0055
Discussion on “Synthetic corundum for jewel bearings” before the Meter and Instrument Section, 6th January, 1933
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1933.0070
The electrical propulsion of ships
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1931.0053
Discussion on “The electrical high-pressure testing of cables and the localization of faults” before the North Midland Centre, at Leeds, 26th January, 1932
http://dl-live.theiet.org/content/journals/10.1049/jiee-1.1932.0055