Mold level control apparatus of continuous casting facility

A periodic disturbance restraining unit 23 is provided with a control component oscillating at a frequency equal to a frequency of a periodic disturbance of a mold level, calculates a mold level periodic disturbance restraining state amount by using a mold level control deviation signal from a control deviation calculating unit 21 and outputs a mold level periodic disturbance restraining signal. A control loop robust stabilization unit 24 receives a mold level steady-state deviation restraining signal from a steady-state deviation restraining unit 22 and the mold level periodic disturbance restraining signal, calculates an operating amount of a stopper so that a mold level control loop of the control apparatus is brought into robust stability and outputs an operating amount signal. A periodic disturbance frequency adapting unit 25 receives a mold level detected value signal and a casting speed detected value signal and detects an oscillatory frequency of the mold level as a periodic disturbance frequency and changes calculation characteristics of the periodic disturbance restraining unit and the control loop robust stabilization unit based on a result of the detection.