DOI:10.1049/pi-2.1951.0001

出版商:IEE    

年代:1951

数据来源: IET

DOI:10.1049/pi-2.1951.0002

出版商:IEE    

年代:1951

数据来源: IET

DOI:10.1049/pi-2.1951.0003

出版商:IEE    

年代:1951

数据来源: IET

摘要:

An experimental electronic computing machine has been constructed, using the serial binary-digital system of number representation. The principle of its operation is explained by means of an analogy; and its design and construction are described in detail. Although the machine is small in size, it has been designed with a view to expansion, and will then be intrinsically capable of performing any computation automatically.

DOI:10.1049/pi-2.1951.0004

出版商:IEE    

年代:1951

数据来源: IET

摘要:

A servo system is described whereby a rotating drum has its angular speed and angular position controlled to fine limits by using a crystal oscillator as a stable reference. The device was developed for use as a “magnetic storage system” forming part of a digital computing machine; it has, however, other possible applications.The various components and their functions are described individually and an overall analysis developed. The theoretical performance is compared with that obtained experimentally, and a discussion of the factors affecting the final accuracy is included.

DOI:10.1049/pi-2.1951.0005

出版商:IEE    

年代:1951

数据来源: IET

摘要:

The use of saturable chokes to provide an automatically variable impedance by static means is now well known. The paper is mainly concerned with a method of determining the size and other design details for any given application in as general a way as possible, by basing it only on a knowledge of the load current and voltage magnitude and ratio to be produced.For reasons set out, empirical methods are preferred for information leading to the available impedance ratio from a given core material. The required impedance ratio is deduced from the application in hand. These two aspects are then brought together to give the design details.The effect on the size of the chokes of their two positions relative to the transformer is considered, and the better arrangement for given application is indicated. Highly sensitive devices with a simple control are specially considered.The paper concludes by indicating an approach to the economic consideration of the use of saturable chokes.

DOI:10.1049/pi-2.1951.0006

出版商:IEE    

年代:1951

数据来源: IET

DOI:10.1049/pi-2.1951.0007

出版商:IEE    

年代:1951

数据来源: IET

摘要:

The paper concerns the protection of long high-voltage transmission lines on which the power-swing conditions are complicated by appreciable line-charging currents. Phase-comparison protection only is considered, depending on the difference in phase between the line currents at the two ends of the line. The problem involved is the study of the power-swing conditions and the setting of them on a phase-comparison diagram on which the protection relay characteristic is already drawn.The application of phase-comparison principles is here developed to a stage which suggests their wider use than at present, and limitations are defined in terms of line constants, including line length and voltage.The diagrams obtained show conclusively which load and power-swing conditions appear in the “trip” section of the phase-comparison field, and a simple envelope is derived mathematically and drawn to include all load and power-swing characteristics of the line. It is shown that the relay settings are determined by the no-load and light-load conditions, and not by the power-swing conditions, which are a problem of impedance protection relays. Although complicated to construct, power-swing curves are already available on the impedance diagram 1. The provision of an easily constructed phase-comparison power-swing diagram should assist in applying phase-comparison protection to long lines.

DOI:10.1049/pi-2.1951.0009

出版商:IEE    

年代:1951

数据来源: IET

摘要:

It is shown first that a degenerative feedback produces no improvement in the zero-drift errors of direct-coupled amplifiers.A method is described whereby these errors can be reduced to any desired amount by the use of an auxiliary amplifier. A single auxiliary amplifier, by means of suitable switching, can be used to correct continuously the balance of a number of main feedback systems. The effects of the balancing circuits on stability are discussed with particular reference to the case where the feedback system is a position-control servo-mechanism.

DOI:10.1049/pi-2.1951.0017

出版商:IEE    

年代:1951

数据来源: IET

DOI:10.1049/pi-2.1951.0044

出版商:IEE    

年代:1951

数据来源: IET