News

Werner Fritz electric motor academy – BLDC motors

Posted on by Linda Andersson
18
Mar

Werner Fritz was head of R&D with Ankarsrum Electric Motors between 1987 to 2024 and has been instrumental for the development of the AEM range of products.

Werner holds a masters degree in electromechanical engineering from the university of Chalmers and worked for Volvo Cars prior to joining Ankarsrum.

Werner Fritz is now working as a senior advisor and is a member of the AEM board.

 

A Brushless DC (BLDC) motor operates on the principles of electromagnetism and is designed to convert electrical energy into mechanical motion. Unlike brushed DC motors, BLDC motors use electronic commutation instead of mechanical brushes and a commutator.

Key Components:

  1. Rotor:
    • Contains permanent magnets.
    • Moves in response to the changing magnetic fields generated by the stator.
  2. Stator:
    • Has windings arranged in multiple phases (typically three-phase: A, B, C).
    • Generates a rotating magnetic field when powered.
  3. Electronic Controller:
    • Switches the current to the stator windings in a precise sequence to maintain rotor motion.
    • Replaces the mechanical commutator and brushes in brushed motors.
  4. Sensors:
    • Hall Effect Sensors (or other feedback mechanisms): Detect the rotor position to synchronize the commutation.

Working Principle:

  1. Electromagnetic Force Generation:
    • When current flows through the stator windings, it generates a magnetic field.
    • This magnetic field interacts with the permanent magnets on the rotor, creating a torque that causes the rotor to spin.
  2. Electronic Commutation:
    • The electronic controller energizes the windings in a specific sequence based on rotor position feedback.
    • This ensures the magnetic fields of the stator and rotor are aligned optimally to produce continuous rotation.
  3. Rotor Position Detection:
    • Sensors, like Hall Effect sensors, determine the rotor’s position and feed this information to the controller.
    • The controller uses this feedback to time the switching of current through the stator windings.
  4. High Efficiency and Precise Control:
    • The absence of brushes reduces friction and wear, improving efficiency and lifespan.
    • Electronic control allows precise regulation of speed, torque, and position.

Types of BLDC Motors:

  1. Inner Rotor BLDC:
    • The rotor is inside the stator.
    • Commonly used for applications requiring compact design and high power density.
  2. Outer Rotor BLDC:
    • The rotor surrounds the stator.
    • Often used in applications needing high torque at low speeds, such as fans and propellers.

Advantages of BLDC Motors:

  • Higher efficiency: Less energy lost to friction and heat.
  • Durability: No brushes mean lower maintenance requirements.
  • Precise control: Ideal for applications needing high precision, such as robotics.
  • Compact and lightweight: Suitable for portable devices and electric vehicles.

 

Common Applications:

  • Electric vehicles (EVs).
  • Drones and UAVs.
  • Cooling fans and pumps.
  • Robotics and automation systems.

The combination of precision and efficiency makes BLDC motors widely used in modern technology.

Ankarsrum Electric Motors offers a new range of BLDC motors with both inner rotor and outer rotor configuration.

Please contact carl.sigfridsson@ankarsrummotors.com for more information.

 

Linda Andersson