摘要:

This is a continuation of the author's previous paper on “The Control of the Domestic Load.”†The usual objection to domestic load control of any kind is that it involves encroachment on the consumer's liberty in using his electricity supply as he thinks fit. To dispose of this objection it is now suggested that the consumer be given the opportunity at any moment and for any period of time readily to change over from a controlled to an uncontrolled supply, and vice versa, the consumption during periods in which the load control is made inoperative being charged at an increased price. This need not be accompanied by two-rate metering or accounting, for the change in price can be effected by a gear-change device in the kWh register or in the prepayment mechanism of the meter, actuated in conjunction with the change-over in the operation of the load control. The necessary modification of apparatus is of a minor nature, and so is the extra cost entailed.

DOI:10.1049/ji-2.1942.0029

出版商:IEE    

年代:1942

数据来源: IET

摘要:

This paper gives an account of the results achieved in an investigation into the magnitude of lightning currents and voltages on high-voltage transmission lines in Nigeria and describes a continuation of earlier work started by one of the authors. Three-phase oscillographic and klydonographic records of voltages were obtained, together with magnetic link measurements of lightning currents on pole and lattice mast structures. Continuous records have also been obtained of the interchange of current between the earth and atmosphere during disturbed weather conditions.

DOI:10.1049/ji-2.1942.0033

出版商:IEE    

年代:1942

数据来源: IET

摘要:

The maintenance of a truly constant speed under conditions of varying load is beyond the capability of a centrifugal governor, an increase in load being associated with a fall in speed coterminous with the increase. If, however, the speed is controlled by comparison with some reliable standard of frequency it may be made synchronous with this standard except during those periods when the load is actually changing.In the apparatus described here the speed of an electric motor is synchronized with a pendulum clock and it is shown that the arrangement will apply corrections for speed deviations as small as ±0.03% on nominally constant loads, and will correct variations as large as ±7.5% which may be caused by changing loads.

DOI:10.1049/ji-2.1942.0035

出版商:IEE    

年代:1942

数据来源: IET

摘要:

In recent years the siting of electricity generating stations has tended to be increasingly affected by non-technical considerations such as legal requirements, amenities and so on. These considerations become of special importance when a particular scheme is submitted to a Public Inquiry by the Electricity Commissioners under Section II of the Electricity (Supply) Act, 1919.The object of this paper is to place on record some considerations which may therefore have to be borne in mind when siting power stations in this country, and at the same time to refer to some factors which have a bearing on power station construction irrespective of location.The paper is not intended to be an exhaustive treatise on the various subjects appertaining to the siting of power stations, but rather to act as a guide to undertakers who are contemplating such action.The paper may be divided into two main parts, the first dealing with considerations arising out of parliamentary legislation, and the second with more technical and practical problems.Reference is made in the first part of the paper to the following items:—(1.1) Town and Country Planning Act, 1932.(1.2) Coal Act, 1938.(1.3) Coal Mines Act, 1930.(1.4) Other statutory requirements.The second part deals with:—(2.1) Chimney emissions.(2.2) Sewage effluent for circulating water.(2.3) Amenities.(2.4) Alternative sites.

DOI:10.1049/ji-2.1942.0036

出版商:IEE    

年代:1942

数据来源: IET

摘要:

This paper describes briefly the construction of typical homopolar and heteropolar inductor alternators, and gives a theoretical basis of design which has produced satisfactory results in practice.It is shown how the ratio of alternating flux to total flux can be calculated in the normal case of rectangular rotor slots and in the special case where the rotor teeth and slots are designed to give a sinusoidal alternating flux wave.In discussing the main types of armature windings it is shown how by maintaining a certain relationship between the number of rotor slots and the number of phases, a single-phase winding may be connected to give a polyphase supply.In the derivation of the armature-reaction formula it is shown that some types of windings cause less armature reaction than others, and also that, except in the case of a true polyphase winding, an efficient damping system is necessary.Methods of predetermining the field current on open-circuit and on load are indicated; the necessity of taking precautions to avoid dangerous bearing currents in the homopolar alternator is discussed, and the paper concludes with an investigation of the losses in these alternators.

DOI:10.1049/ji-2.1942.0037

出版商:IEE    

年代:1942

数据来源: IET