Abstract :
R. H. Earle: In the development of the hydraulic division of automatic control systems for hydro electric units, it has been the experience of the writer that the major problem is to obtain the desired action of the turbine gates during the periods of starting and stopping the machine. In response to electrical signals the turbine gates must be opened or closed and the gate opening must be controlled in such a manner as to prevent violent speed changes and to prevent unnecessary shocks to the machine itself, the water conduits, and the power system. As stated by Mr. Wensley this action is secured by modifying the usual governor system, by using motor-operated gates, or by using a special electrically controlled service motor to move the gates.