A control apparatus for an electric rotating machine for performing drive control of the electric rotating machine, the control apparatus comprising: - current detection means for detecting electric rotating machine currents (iu, iw) flowing in the electric rotating machine; - position estimation means for estimating the position of a rotor of the electric rotating machine, based on the electric rotating machine currents (iu, iw) detected by the current detection means; - control means for outputting voltage instructions (Vup*, Vvp*, Vwp*), based on the electric rotating machine currents (iu, iw) detected by the current detection means and information about the position (θL) of the rotor estimated by the position estimation means; - voltage application means for applying a voltage for drive control to the electric rotating machine, based on the voltage instructions (Vup*, Vvp*, Vwp*) outputted from the control means; - the control means including a drive voltage instruction calculation section for calculating drive voltage instructions (Vu*, Vv*, Vw*) for driving the electric rotating machine; - the control means including a position estimation voltage generator for outputting position estimation voltage instructions (Vuh, Vvh, Vwh) for estimating the position (θL) of the rotor of the electric rotating machine, - the control means including a noise reduction voltage generator for outputting noise reduction voltage instructions (Vum, Vvm, Vwm) having frequencies different from those of the drive voltage instructions (Vu*, Vv*, Vw*) and from those of the position estimation voltage instructions (Vuh, Vvh, Vwh); and - the control means including adders for adding the position estimation voltage instructions (Vuh, Vvh, Vwh) and the noise reduction voltage instructions (Vum, Vvm, Vwm) to the drive voltage instructions (Vu*, Vv*, Vw*), and outputting the resultant signal as the voltage instructions (Vup*, Vvp*, Vwp*) to the voltage application means; and - a filter for removing the same frequency component as that of the position estimation voltage instructions (Vuh, Vvh, Vwh) from the noise reduction voltage instructions (Vum, Vvm, Vwm) is provided between the noise reduction voltage generator and the adders. - current detection means for detecting electric rotating machine currents (iu, iw) flowing in the electric rotating machine; - position estimation means for estimating the position of a rotor of the electric rotating machine, based on the electric rotating machine currents (iu, iw) detected by the current detection means; - control means for outputting voltage instructions (Vup*, Vvp*, Vwp*), based on the electric rotating machine currents (iu, iw) detected by the current detection means and information about the position (θL) of the rotor estimated by the position estimation means; - voltage application means for applying a voltage for drive control to the electric rotating machine, based on the voltage instructions (Vup*, Vvp*, Vwp*) outputted from the control means; - the control means including a drive voltage instruction calculation section for calculating drive voltage instructions (Vu*, Vv*, Vw*) for driving the electric rotating machine; - the control means including a position estimation voltage generator for outputting position estimation voltage instructions (Vuh, Vvh, Vwh) for estimating the position (θL) of the rotor of the electric rotating machine, - the control means including a noise reduction voltage generator for outputting noise reduction voltage instructions (Vum, Vvm, Vwm) having frequencies different from those of the drive voltage instructions (Vu*, Vv*, Vw*) and from those of the position estimation voltage instructions (Vuh, Vvh, Vwh); and - the control means including adders for adding the position estimation voltage instructions (Vuh, Vvh, Vwh) and the noise reduction voltage instructions (Vum, Vvm, Vwm) to the drive voltage instructions (Vu*, Vv*, Vw*), and outputting the resultant signal as the voltage instructions (Vup*, Vvp*, Vwp*) to the voltage application means; and - a filter for removing the same frequency component as that of the position estimation voltage instructions (Vuh, Vvh, Vwh) from the noise reduction voltage instructions (Vum, Vvm, Vwm) is provided between the noise reduction voltage generator and the adders.