A motor control system includes a motor, an encoder, and a controller including a controller transmitter configured to transmit a torque command to control the motor. The encoder includes a position detector configured to detect a rotational position of the motor, an encoder receiver configured to receive the torque command from the controller transmitter, first disturbance estimating circuitry configured to estimate a first disturbance torque based on the rotational position and the torque command, and an encoder transmitter configured to transmit the rotational position and the first disturbance torque to the controller.