| 摘要 |
PURPOSE:To eliminate the overloads of all induction motors by maintaining suitable load states of the motors in response to the speeds of the respective motors when the motors connected in parallel are operated by power from an inverter. CONSTITUTION:The speed signals N1, N2 of Nos. 1 and 2 induction motors 5, 6 are respectively input to a preferential circuit 101 and a speed difference calculator 200. A low speed side speed signal is selected if the both motors are power driven and a high speed side speed signal is selected if braked on the basis of the command of an operation instructing unit 100 from the circuit 101 to be output to a speed/frequency converter 102 and a speed difference calculator 200. The calculator 200 totalizes the difference between the detected speed and the speeds of the motors. The torques corresponding to the motor speeds are generated by using the difference of the torque current of the current command from the product of the exciting current component of the current command and the total value of the speed differences as the torque current component command value. |
