This April, Virtual UAV Manufacturers Meet Up, organized by MicroPilot, provided its audiences with engaging webinars and discussions on subjects most relevant to the industry. A regular participant, ePropelled provided its experts to address efficiency.  

Our Global CTO and MD, Dr. Nabeel Shirazee, supported by our head of UAV, Kenny Grewal, presented a session entitled “How Propulsion Motors and Motor Controllers Can Work Together to Improve Efficiency.”  

In it, Nabeel stressed that motors and controllers need to be designed together because this ensures optimized and most efficient performance. But to achieve this, several factors need to be considered, including: 

  • Motor magnetic, electrical, and thermal parameters 
  • Motor controller parameters 
  • Tuning between motors and motor controllers 

The electric propulsion system for UAVs 

There is much more involved in tuning and matching motors and controllers than hooking them up and making sure they work. Purchasing them separately and plugging them in is not going to ensure that they work together efficiently.  

When looking at the motor, there are multiple parameters we need to consider, including: 

  • The number of magnetic poles 
  • The flux linkage 
  • Resistance  
  • Inductance 
  • Voltage 
  • Current 
  • Speed range 
  • Temperature range 
  • Motor constants 

If that wasn’t enough, we also need to consider a lot of parameters for the controllers, including: 

  • Motor tuning capability 
  • Motor control topology 
  • Voltage range 
  • Current range 
  • Switching frequency 
  • Advance angle control  
  • Cooling 

If motors and their controllers are developed together and matched, their performance will be optimized in ways that are unlikely if they’re purchased from different manufacturers. Even tuning between them can come with caveats that some users might not even be aware of. For example, tuning the motor needs to be done without the propeller first.  

Forgotten parameters 

When the motor and the controller are connected, motor identification algorithm and the motor control topology are a huge part of the optimization. But it’s not the full story. After the tuning is done, the propeller needs to be attached (with adapters if necessary). But which propeller? Its size needs to match the voltage, speed, and thrust requirements and it has to be based on mission parameters. But without knowing what propeller size is best for what mission parameters, how can it be chosen well?  

There are also other design parameters that include, among others, takeoff weight and the required thrust. All of this, and more, needs to be considered to ensure the optimal and most efficient performance from the motor and controller.  

To learn more about the subject, watch the free webinar here. 

Nabeel holds degrees in electrical and electronic engineering and in magnetic engineering. He earned his Ph.D. at Cardiff University, where he developed a permanent magnet lifting system that the university patented. His interest in magnetics and materials science is pushing his research and his work forward and we were very proud that he could present some of his work during the webinar.