| 摘要 |
<P>PROBLEM TO BE SOLVED: To control the torque of a three-phase AC induction motor for a web winder through a simple circuit. <P>SOLUTION: A torque controller generates a three-phase AC current with an inverter 3 from a DC power source 6, thereby driving the three-phase AC induction motor 1. It measures the number of revolutions of the three-phase AC induction motor 1 with a speed detector 4, thereby getting an angular velocity ωm of a rotor. It adds the angular velocity of the rotor, measured with the speed velocity 4, to the slide angular velocity corresponding to a slide frequency set to an optimal value, thereby getting drive angular velocity. It generates a stator voltage command for zero izing a value obtained by subtracting 9/8 times of the square of a stator current from the square of a torque component current corresponding to a torque command, with a PID control means. It generates a three-phase sine wave, according to a stator voltage command and a field angular velocity command. It controls the inverter 3 with a signal in which the three-phase sine waves are PWM-modulated with a PWM circuit. It keeps its target torque with only the current detector 5 and the speed detector 4, while keeping the slide frequency constant. <P>COPYRIGHT: (C)2011,JPO&INPIT |
