Brushless DC Motor Primer
This article gives a broad picture of the landscape of permanent magnet brushless motors and controls from the stand point of motor design, application engineering and manufacturing processes. It is written to give top management of OEM equipment makers, a clear and concise overview of brushless DC motors and associated drive electronics from the stand point of how the application of this technology can enhance the OEM’s own competitive advantages. Motors are often the most expensive part in an OEM product and they also often contribute most to the OEM's equipment's feature set. So it follows that a clear understanding of the latest developments in motor technology is important and indeed necessary for the designers and top managers of OEM's. This overarching article covers the following broad topics:
- From first principles, fundamentals of torque, its definition and generation.
- Different types of electric motors and their pros and cons. An introduction to Motor Constant, a key figure of merit for comparison of different motors.
- Brushless motor benefits.
- Costing of brushless motors and the major cost components.
- Manufacturing processes of brushless motors.
- Nuances of brushless motors: Y versus delta winding, sensorless controls, microprocessor based controls, direct drives, custom versus standard designs, noise reduction techniques, design considerations for very harsh environments, design considerations for weight reduction, design considerations for high reliability.