ROTARY SPEED SETTING CIRCUIT FOR TURBINE GOVERNOR

PURPOSE:To prevent overexcitation of a transformer or the like in an electric power system in which a turbine generator is incorporated by fixing a condition at the time of completing the speed up of a turbine and a lower limit speed preset value. CONSTITUTION:In a governor of a turbine, OR circuits 24, 26 for giving an up command and a down command are connected to a rotating speed setting device 10. The down command is input to the setting device 10 through a wipe- out circuit 52 controlled by AND circuit 50. An excitation on-operating signal as a speed up completion signal of the turbine and a lower limit speed preset value are input to AND circuit 50, and the AND circuit 50 is adapted to output a down command only when both conditions are satisfied. Thus, the turbine is interlocked so that the rotating speed preset value will not become less than the lower limit value to prevent overexcitation of a main transformer or the like.