Patent ID: 8362735
Filing Date: 2013-01-29
Classification: G05B,H02H,H02P

Abstract:
1. A system for saving power consumed by an induction motor, the system comprising: a source of AC voltage; a processor; a means for controlling power to the induction motor, the means for controlling power connected in series with the source of the AC voltage and the induction motor, the means for controlling including a trigger, the trigger controlled by the processor to fire the means for controlling at a trigger delay into each cycle of the AC voltage, whereas full power is supplied to the induction motor when the trigger delay is zero; a means for measuring current drawn by the motor; a means for measuring the AC voltage; a means for measuring a phase difference between a phase of the AC voltage and a phase of the current; a means for initializing power provided to the induction motor, the means for initializing determining a minimum phase angle, a minimum trigger delay, a maximum trigger delay and an over-current value; and a means for continuously varying the trigger delay between the minimum trigger delay and the maximum trigger delay, if the trigger delay is greater than zero the trigger delay is decremented when the phase difference is less than the minimum phase angle and if the trigger delay is less than the maximum trigger delay, the trigger delay is incremented when the phase difference is greater or equal to the minimum phase angle and the trigger delay.