DOI:10.1049/piee.1964.0011

出版商:IEE    

年代:1964

数据来源: IET

摘要:

The paper describes a method of analysis and design for a new type of multispeed pole-change machine. The development of these new machines, which employ phase-mixing techniques, was outlined in an earlier paper. The analysis initially uses simple current sheets to replace the practical windings and subsequently shows how the additional harmonics produced by practical windings may affect the machine performance. The material is supported by experimental results from two machines.

DOI:10.1049/piee.1964.0012

出版商:IEE    

年代:1964

数据来源: IET

摘要:

The conventional ideas concerning power-system stability are briefly outlined. Some ways in which the automatic voltage regulator and velocity-sensitive governor have modified these ideas by showing their effects qualitatively on alternator swing curves are indicated. They indicate that overall stability cannot with certainty be assessed from the first rotor swing, and the paper concludes by showing how, for some particular system conditions, the machine control devices modify transient stability.

DOI:10.1049/piee.1964.0013

出版商:IEE    

年代:1964

数据来源: IET

摘要:

The paper describes an investigation into the contribution that a conventional velocity governor controlling the input power to a synchronous generator makes to the transient stability of a typical power-system configuration. It seeks to ascertain the corresponding transient-stability effect using an alternative operating signal, derived from rotor acceleration, for the control of input power. A governor actuated from a compound of velocity and acceleration signals is described, and its effect on transient stability is compared. The effects on this stability of varying some of the parameters of the system, the machine and the governor are described. The paper concludes with a brief study of the effect of various governors on the transient stability of a synchronous generator connected to a large system by a single faulted transmission line that is fitted with autoreclosing circuit breakers.

DOI:10.1049/piee.1964.0014

出版商:IEE    

年代:1964

数据来源: IET

摘要:

A power-system computer is described that combines an analogue computer for the representation of the synchronous generator with a network analyser for the representation of the transmission network. These two forms of computer are coupled to give an overall representation that facilitates the study of the transient performance of a synchronous power system in unbalanced fault conditions.In the studies described, the system represented is that of a synchronous generator connected to an infinite busbar through a double-circuit transmission line, one circuit of which is subjected to a series of unbalanced and balanced faults. Studies of the effect of fault type, fault resistance, system neutral earthing and single-phase autoreclosing are included. For purposes of comparison, and in view of their ubiquity on a modern power system, automatic-voltage-regulator and speed-governor representation are included in some of the studies.

DOI:10.1049/piee.1964.0015

出版商:IEE    

年代:1964

数据来源: IET

摘要:

The paper considers the detailed operation of a typical steam-turbine governor of the form widely used in conjunction with synchronous generators connected to large power systems.The role played by the prime-mover governor in the transient performance of the synchronous generator is not yet fully elucidated. The research team at the University of Newcastle upon Tyne has been studying governor effects by computer techniques, and the simulation described is associated with this work.It was regarded as essential to express the governor performance under conditions of transient disturbance of the power system with accuracy, although it was also necessary to have a representation that was simple relative to that of the power system and electrical generator. The paper develops and justifies alternative transfer-function representations of the governor system for the problem defined.

DOI:10.1049/piee.1964.0016

出版商:IEE    

年代:1964

数据来源: IET

摘要:

A systematic experimental and theoretical study was made of the effect of various inherent and extraneous circuit parameters on the commutation oscillations and on the period of commutation overlap in a static power convertor. The initiation of oscillations by a voltage jump occurring across a convertor device at the start and at the end of commutation overlap was analysed for a variety of conditions, and the theoretical deductions were experimentally verified. The period of commutation overlap in a convertor without extraneous capacitances and in steady-state operation was shown to be determined by the sum of the instantaneous values of direct current prevailing at the start and the end of the overlap. Enforced reductions of the period of commutation overlap were found to be obtained by an appropriate adjustment of the magnitudes of the relevant parameters in a controlled-rectifier circuit either with capacitors connected between the anodes of the convertor devices or with capacitors connected between the input terminals of the convertor transformer in the presence of series inductances in the a.c. supply lines.

DOI:10.1049/piee.1964.0017

出版商:IEE    

年代:1964

数据来源: IET

摘要:

Two methods have been evolved to determine the commutation reactance of a transformer operating in a rectifier or invertor circuit. One of the methods, called the commutation-overlap method, gives an accurate value. The other, designated the area-loss method, is simpler in evaluation and gives an approximate value, the approximation being closer as the d.c. waveform approaches smoothness.Using a particular built-in probe-coil arrangement on a 3-phase convertor-transformer (with cylindrical windings of equal height) to probe the leakage flux, it was found that the probed leakage inductance remained invariant in the three conventional short-circuit tests for a 3-phase rectifier-transformer as well as in rectifier and invertor operation of the transformer. It was concluded for the type of transformer used that the short-circuit reactance is independent of the method of test, and that the commutation and short-circuit reactances are identical.

DOI:10.1049/piee.1964.0018

出版商:IEE    

年代:1964

数据来源: IET

DOI:10.1049/piee.1964.0025

出版商:IEE    

年代:1964

数据来源: IET

摘要:

Methods for obtaining the response of a nonlinearity to several uncorrelated inputs are considered. The majority of these methods involve approximate solutions that can lead to rapid calculation of the various output terms, and in most cases a sufficiently high degree of accuracy can be obtained without excessive labour. The concept of the modified nonlinearity is introduced and its value calculated in some cases. It is shown how, under certain conditions, its use may be extended to deal with a double-valued nonlinearity. An example is given to illustrate how the concept may be applied to the design of a simple adaptive system.

DOI:10.1049/piee.1964.0026

出版商:IEE    

年代:1964

数据来源: IET