How To Select a DC Motor Coil Based on the Required Working Point and Power Supply 

Although DC motors have a common operating principle, many applications — including portable medical devices like infusion pumps — require one that converts electrical energy to mechanical energy with the highest efficiency to achieve a long, reliable service life. This is typically where an ironless DC motor comes in.
Portescap’s Athlonix™ ironless DC motor with precious metal commutation can be ideal for high-efficiency, high-reliability applications like portable medical devices. In circumstances where these motors 
Hand and motor 041_prvsupport the maximum continuous power needed to operate at the required speed and torque, you only have to select the motor coil. To choose the right motor coil, keep these two key points in mind:
  • The maximum continuous torque of a DC motor depends on the motor’s heat dissipation capability and, therefore, mainly on its dimensions. Changing the coil of a DC motor will not impact its maximum continuous torque.
  • Changing the coil makes it possible to adapt the motor to the available power supply voltage and current to create an efficient motor system.

When identifying the right DC motor, you may not always have the option of customizing the coil. Developing a new coil requires a time and money investment by both the customer and the motor manufacturer. If a current source power supply is available, you can achieve your desired working point using a catalog coil. However, if catalog coils cannot achieve the desired working point, consider a custom-designed coil that is adapted to the power supply.

 Best Practices for Motor and Coil Selection

When your application requires a high-efficiency DC motor and coil, remember these key considerations:

  • Choose your motor size based on the required mechanical power. The motor must be large enough to develop the necessary torque and dissipate the heat generated through losses in the motor.
  • While choosing the motor coil, pay attention to the available power supply. A motor supplier will typically offer a set of coils that can achieve the same working point with different voltage and current requirements.
  • For a high-efficiency motor, the required mechanical power must be created with high speed and low torque. In order to achieve this, select a coil that takes the most advantage of the available power supply.

 A dedicated motor provider that keeps these considerations in mind is ideally suited to help customers identify the right motor and coil combination for their application.

 To discuss further, read the complete white paper or contact an engineer.