Power supply for generating station auxiliary services

The object of the paper is to analyse the factors governing the design of power supply and distribution systems for generating station auxiliary services. Considerations are limited to methods having practical application when designing modern stations, and, though there are difficulties preventing the achievement of any high degree of standardization of the auxiliary systems, a, number of generally accepted trends can be found. With the commonly adopted use of electric drives for all auxiliary services, the necessary degree of service reliability can be achieved by a suitable design of the auxiliary distribution system, mainly by application of the principle of divided auxiliaries, and by the use of proper sources of auxiliary power supply. In respect of this last point, the common practice in this country is to use unit transformers or shaft generators. A number of typical schemes are represented diagrammatically to illustrate various possible alternatives.