A control apparatus includes: a control computing unit that generates an operation amount based on a control deviation, calculated by performing subtraction of a command value and a control amount, and a control gain; an adjustment-execution-command generating unit that generates an adjustment-execution command value indicating ON or OFF; a binary output unit that generates an adjustment-time addition value based on the control deviation and a hysteresis-width setting value; a standard-deviation estimating unit that calculates a low-frequency-component removed signal obtained by removing low-frequency components of the control amount or the control deviation and calculates a standard-deviation estimated value, which is an estimated value of a standard deviation; and a hysteresis-width computing unit that calculates a hysteresis-width computed value based on the standard-deviation estimated value and changes the hysteresis-width setting value of the binary output unit to the hysteresis-width computed value.