摘要:

The paper covers the development of the distribution system in the south-west of England from nationalisation up to the present time. Early rural electrification problems and developments are discussed, together with standardisation during the period of rapid load and system growth. The influence on an Area Board of the change in the price of basic fuels, together with the effects of recession and adjustment to a continually changing environment, are included. Current problems of system maintenance and replacement, the use of mechanical aids to productivity and the ability to cope with widespread system emergencies are discussed, following on to future trends highlighting the impact of computer and telecommunications technology and information systems leading to an integrated resource management system. The importance of utilisation and the role of professional engineers in marketing and advice to consumers, in industrial, commercial and domestic applications, is stressed. The paper demonstrates the wide breadth of engineering now covered in an electricity supply Area Board.

DOI:10.1049/ip-c.1985.0001

出版商:IEE    

年代:1985

数据来源: IET

摘要:

There is much interest in using renewable energy sources, such as wind, wave and solar, to generate electrical energy. Unfortunately, such energy sources are intermittent, and, therefore, conventional sources must still be available to meet the demand during quiescent periods. Hence, the reliability and economic assessment of these novel sources cannot be made using standard capacity-replacement-based methods; instead, energyreplacement methods are required. The paper extends the loss-of-energy-expectation method to evaluate the generation reliability including novel energy sources. These results are then used to calculate the economic benefits of such sources. The approach is illustrated using the IEEE reliability test system. Although the paper concentrates on wind energy sources, the technique and approach are applicable to a generation system containing any type of intermittent energy source.

DOI:10.1049/ip-c.1985.0002

出版商:IEE    

年代:1985

数据来源: IET

摘要:

An adaptive stabiliser that supplements the excitation control signal of a synchronous machine is presented in this paper. A pole-shifting algorithm that radially shifts the poles towards the origin is described. Also, because of the nonlinear characteristics of the synchronous machine, the algorithm is modified such that the system identification is turned off for a short period following the onset of a severe disturbance. Both simulation and experimental results show that the proposed algorithm gives a consistently improved performance, particularly during large disturbances.

DOI:10.1049/ip-c.1985.0003

出版商:IEE    

年代:1985

数据来源: IET

摘要:

The paper considers a novel way of scheduling generations and loads for enhancing stability of overall power systems. Based on a so-called structure-preserving model, an algorithm is proposed for correcting the dynamically insecure system. The algorithm proposed aims at online computer applications. In the event of an emergency, the percentage load to be shed and the busbars which are affected would aid the system operator, as is illustrated by the application of the algorithm on a sample 5-busbar power system. The algorithm aims at minimising deviations from an economically optimum operating point which is the usual choice for alternative operation of power systems.

DOI:10.1049/ip-c.1985.0004

出版商:IEE    

年代:1985

数据来源: IET

摘要:

A control scheme based on a variable-structure-system concept is applied to the problem of automatic generation control of interconnected power systems. The proposed algorithm is simple and easy to implement. The effect of generation-rate-constraint nonlinearity on the dynamic performance of the system for reheat- and nonreheat-type steam turbines is also studied. A comparison of the conventional and the proposed variable-structure control strategies shows that, with the application of the proposed algorithm, the system performance is improved significantly.

DOI:10.1049/ip-c.1985.0005

出版商:IEE    

年代:1985

数据来源: IET

摘要:

A computationally efficient means of determining the location of a static VAR compensator, to maximise its influence over damping of electromechanical oscillations, is presented. The location criterion, which is independent of the ultimate control scheme to be used, is applied to two-machine systems. An extension of the criterion to multi-machine systems, using modal analysis, is demonstrated on a simple three-machine system. Confirmation of the criterion is supplied by transient stability runs on a simple two-machine problem.

DOI:10.1049/ip-c.1985.0007

出版商:IEE    

年代:1985

数据来源: IET

摘要:

A new estimate has been made of the RF power injected by an HVDC convertor pole into the DC yard. The RF power levels measured provide a design basis for either an active or passive RF filter for the protection of a power-line carrier system of a convertor station of this type.

DOI:10.1049/ip-c.1985.0008

出版商:IEE    

年代:1985

数据来源: IET

摘要:

M- toN-phase transformers (M≠N) are considered in the phase co-ordinate frame of reference. Equivalent circuits are derived for zig-zag, Scott, T-T and star-double-star transformers, and the connection tables are given for use in assembling the nodal-admittance-matrix terms in the usual way for power network analysis. The paper concludes with an example of a polyphase load-flow analysis of a network containing some of these transformers.

DOI:10.1049/ip-c.1985.0009

出版商:IEE    

年代:1985

数据来源: IET

摘要:

The opening of one or two conductors in three-phase circuits supplying an ungrounded transformer produces a steady-state overvoltage due to ferroresonance between the lateral capacitance and the transformer nonlinear inductance. Available methods of determining the conditions under which such an overvoltage may occur are mostly based on experimental studies, and hence are limited in application to systems whose design parameters are similar to those used in the tests. A simple and elegant approach, presented here, reveals that an incorrect choice of overvoltage limit leads to the selection of an unsafe lateral length, resulting in a potentially dangerous high voltage across the connected apparatus and protective equipment. Generalised mathematical equations are developed to determine the safe lateral length as a function of transformer size for the prevention of the overvoltage problem due to open conductors in three-phase systems. The computed results are in good agreement with experimental observations.

DOI:10.1049/ip-c.1985.0010

出版商:IEE    

年代:1985

数据来源: IET