Position controller of motor

A position controller of a motor in which the position time can be shortened even if an external force is applied. A speed control unit ( 13 ) comprises a compensation low-pass filter ( 133 ) having a transfer function corresponding to a delay of a speed control system. The speed control unit ( 13 ) further comprises an integral control system including a speed integrator ( 132 ) for integrating the difference between a speed and a delay speed command to the low-pass filter ( 133 ) compensating the delay in the speed control unit. A proportional control system outputting a command proportional to the speed command, and a multiplying means ( 134 ) for multiplying the sum of outputs from the integral control system and the proportional control system by a speed proportional gain and outputting the result as a torque command. A speed feedback low-pass filter ( 135 ) having a transfer function for preventing a ripple from appearing in the torque command due to a quantization error and/or a positional error at a position detection unit is also provided.