Provided is a motor having a magnetic polar unit in which a permanent magnetic polar array having arranged therein alternately a plurality of permanent magnetic polar elements in alternate opposite poles is made to face a plurality of electromagnetic coil arrays alternately excited at opposite poles, and the permanent magnetic polar array is made to move thereby; wherein the motor further comprises a sensor for detecting the periodical magnetic change accompanying the movement of the permanent magnetic polar array, the output of the sensor is directly returned as a direct drive waveform to the electromagnetic coils, and this drive circuit forms the excitation signal based on the return signal.