Improving AC Motor Efficiency with Fuzzy Logic Energy Optimizer

摘要

The paper discusses EPA's research program to develop fuzzy-logic-based energyoptimizers for alternating-current (AC) induction motors driven by Adjustable Speed Drives (ASDs). The technical goals of the program are to increase the efficiency of ASD/motor combinations (especially when operating at off-rated torque/speed conditions), develop a generic controller for energy optimization that can be applied to a wide range of motors and ASDs regardless of size and application, and develop a controller for energy optimization that can eliminate the requirement for tachometer or encoder feedback, and still maintain the stability and response of closed-loop control. Electric motors use over 60% of the electrical power generated in the U.S. The U.S. population of approximately 1 billion motors use over 1700 billion kWh per year. Over 140 million new motors are sold each year. A review of the U.S. motor population reveals that 90% of the motors are less than 1 hp (fractional motors) in size, but use less than 10% of the electricity consumed by motors. More that 80% of the electricity used by motors is consumed by less than 1% of the motor population (motors greater than 20 hp). Thus, it is clear that large energy savings from improvement in motor efficiency could be achieved from a relatively small motor population.