| 摘要 |
PURPOSE:To perform the control of the induction motor without using an A-D converter by a method wherein a microcomputer, in the memory of which a torque to amplitude characteristic, a torque of phase difference characteristics, a rotational speed to slip characteristic and a rotational angle to sine wave value characteristic are memorized, is used. CONSTITUTION:The deviation ER of a speed command VCMD and an actual speed TSA is calculated by an adding and subtracting circuit 15. The microcomputer 22 is equipped with a processing device 22a, a control program memory 22b and a data memory 22c, and the deviation ER which is proportionally integrated to the deviation ER sent from a polarity discriminating circuit 17 is inputted. The microcomputer 22 calculates the three-phase sine wave Iu, Iv and Iw, and the primary current amplitude I based on the torque to amplitude characteristic, the torque to phase difference characteristic, the rotational speed to slip characteristic and the rotational angle to sine wave value characteristic memorized in the data memory 22c, and gives the calculated value to the induction motor control circuit 30. Accordingly, the motor 11 can be controlled by the small bit microcomputer. |
