Supermizer-energy saving system for 3-phase AC induction motors

Hitherto, mechanical devices such as dampers and valves have been often used to regulate the amount of flowing fluid-air or water, for fans, blowers or pumps with induction motors powered by the commercial mains supply. With this arrangement, only marginal reduction in power consumption is achieved even if the amount of flowing fluid is decreased, on account of the constant motor speed at the fixed commercial mains supply frequency. The amount of flowing fluid is directly proportional to the motor speed. The pressure is proportional to the square of it. The axis power, that is also the consumed power, increases in proportion to the cube of the motor speed. Decreasing the motor speed for achieving a reduced flow rate is therefore an effective means of energy saving on account of the reduction in power consumption. However, as is well known, the induction motor is designed such that its speed will increase when its load is lightened. This results in a reduction in its efficiency on account of the deviation from its rated slip. The Supermizer (SMX) introduced in this paper detects motor load variations accurately at a high sampling rate and regulates both the current and the voltage delivered to any motor so as to bring about maximum energy savings by continuously operating along the built-in optimal operating power factor curve without affecting its torque and speed.<>