Solid State AC Motor Drives - Conservation Perspectives

This paper presents and discusses techniques for energy conservation by reducing losses in ac motor driven systems, proposed by the technical community in response to surging cost of energy. An important aspect considered is the impact on electric utility systems in terms of harmonics and power factor of operation. The techniques evaluated in this paper are listed below. 1. NASA Power Factor Controller: is a simple device for reducing power losses in lightly loaded ac motors. 2. Conventional Variable Frequency Solid-State Inverters: can control the speed of ac motors by producing adjustable frequency ac voltage, with an enormous potential for energy conservation in pumps and air handling systems. 3. Other Variable Frequency Drives: include cyclo converters, slip-recovery scheme, permanent magnet synchronous motors, etc