Brushless Servo operating principles

By G Craig, Techlyn


Published in:

Electricity+Control, July 2015 (pages 26 – 28)

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A servo motor is a highly specialised device. Like an ordinary electric motor, it requires detailed design and a thorough understanding of the operating principles.

Brushless servomotors have largely replaced brush motors, offering simple construction, absence of electrical rubbing parts (brush/ commutator) and high speed capability. In addition, the heat developed by the windings is developed in the outside (stator) of the motor where it is dissipated by convection and conduction via the motor mountings.


Take note

  • Brush motors have been largely replaced by brushless servo motors.
  • Servo motors must be precisely controlled and be powerful and robust enough to serve their purpose.
  • Great care must be exercised as regards minimising the influence of EMI in the accurate operation of a servo motor.