Electric drives for steam-electric generating-station auxiliaries

For several years there has been an increasing trend toward all-electric drives for steam-station auxiliaries on account of the recognized advantages in flexibility-; convenience, low operating cost, and comparable investment cost. Substantial economies in first cost also have been obtained along with further improvements in flexibility through the use of transformers as the sole means of station power supply. Gratifying reliability of performance has been achieved by co-ordinating design, backed by extensive tests, including momentary interruptions of station power supply, and has been incorporated in approximately 500,000 of modern plants of the 850-pound 900-degrees-Fahrenheit powdered-fuel-fired unit type. Operating experience has demonstrated the over-all reliability and economy of all-electric drives for station auxiliaries and of the use of transformers as the sole source of station power supply.