| 摘要 |
PURPOSE:To solve the problem of rotation speed irregularity due to cogging torque generated regarding the magnetic pole of the permanent magnet of a DC motor and the salient pole of an armature core. CONSTITUTION:A speed error detection circuit 4 compares the rotary synchronization signal from a frequency generator 3 with a target rotation period and then outputs an error signal and a speed control circuit 5 outputs a torque signal so that the error signal of the speed error detection circuit 4 is lost. A torque pattern generation circuit 7 outputs a specific pattern for one rotation of a motor 1 in synchronization with the output signal of a pulse generator 6. The output of the speed control circuit 5 and that of the torque pattern generation circuit 7 are synthesized by an adder 8 and then a control circuit 2 generates a torque corresponding to signal at the motor 1. By outputting a torque pattern for canceling cogging torque from the torque pattern generation circuit 7, the influence of the cogging torque is lost and the speed controller of a DC motor with improved characteristics without any rotation speed irregularity can be obtained. |
