Electrical machines and drives: present and future

The paper discusses the present and future of electrical machines and variable-speed drives. Although at present improved DC drives are emerging the market for DC drives is expected to fall and AC drives will dominate the market. Different manufacturers have released various universal drives, and it is expected that other similar drives will also emerge. There will be an increase in vector-controlled drives (speed-sensorless implementations as well), permanent magnet synchronous motor drives and different types of reluctance motor drives (switched reluctance motor, synchronous reluctance motor). Various drives, including vector and direct torque controlled drives are also discussed and compared. It is also shown that there will be a revolution in the packaging of drives and also in the application of various intelligent control techniques, (fuzzy, neural, fuzzy-neural etc.) techniques. Drive efficiency will be a critical issue. Trends for minimum configuration DSP controlled drives are also discussed. Results of a survey on the future of drives are also presented. This involves a large number of manufacturers.