摘要 |
PURPOSE:To control the motor with an extremely limited torque ripple by producing a current pattern in multi-phases employing a magneto-sensitive element for detecting the density of the magnetic flux. CONSTITUTION:As the density of two field system fluxes interlinked with two armature windings changes roughly in a sine wave following the rotation of the rotor, the output presenting a wave proportional to the sin wave at the output terminal of two magneto-sensitive elements. After added at the input stage of the pattern formation circuit 100, the output is applied to an amplifier 101 to produce the output VR. The waveheight of the output is invariably constant regardless of the rotational speed and variation of the load and the maximum and the minimum level developing at a cycle of electrical angle pi/2 is always fixed, where the relation of about 2<1/2>:1 is established between the two values. In addition, the processing of the output VR with a diode 104 and an amplifier 102 produces a constant output V equivalent to (2<1/2>+1)X(the minimum value of the output VR). The passage thereof through a differential amplifier 103 with the output VR forms a current pattern with a limited ripple. |