Historical approach to speed and tie-line control

THE PROBLEM of matching the generation to the load is basic with the electrical industry. Since the very earliest days of a-c systems, the maintenance of a frequency equal to the nominal figure at which the system operates has provided the simplest indication of this balance. Until the late 1920´s very little consideration was given to anything more than approximate accuracy of frequency, with the result that deviations from normal of as much as 1/2 cycle were not at all uncommon. Integrated time was of no consequence.