| 摘要 |
PURPOSE:To obtain a DC drive motor control circuit having high mechanical operability in a mechanical system in which a load varies abruptly by raising the transfer gain of a speed control circuit when the speed of a DC motor exceeds the vicinity of the rated speed and thus preventing the overspeed thereof. CONSTITUTION:In a control circuit of a DC motor connected to a mechanical system having a load abruptly varying with low intrinsic vibration frequency, a gain compensator 8 to which the output from a speed feedback detector 6 is inputted is provided, and the output from the detector 6 is inputted to a subtractor 7 provided in the next stage of a proportional compensator 2 of a speed control system. When the speed of the DC motor is lower than the rated value, the compensator 8 will not produce an output. When it exceeds the rated value, it produces an output proportional to the value exceeded to increase the speed feedback amount. Thus, the response speed of the automatic speed control system is equivalently raised to eliminate the overspeed state of the DC motor at the time of impact rise of the load or the like. |
