Automatic Control of Hydroelectric Generating Stations

This paper discusses hydroelectric station equipment, operating procedures and the factors involved in applying automatic control. Hydraulic governors and the types of water wheels (impulse, reaction, fixed propeller, and adjustable propeller) are described from the electrical engineer´s viewpoint. A typical automatic control diagram is shown for each of the two methods commonly employed for accelerating the generator and synchronizing it with the system. In one method, termed self-synchronizing, the machine circuit breaker is closed at less than synchronous speed, and the machine synchronizes after its field is applied. In the other method, automatic speed matching and synchronizing equipment bring the machine on the line at correct voltage and phase angle. Considerations involved in applying supervisory control to automatic hydroelectric stations are presented.