The choice of motor in a drone is critical to its performance, stability, and efficiency. Whether you are building a drone from scratch or selecting a ready-made UAV, understanding which motors are commonly used and how to choose the right one can significantly impact flight time, payload capacity, and maneuverability.
This article provides a comprehensive guide on motors used in drones and practical tips for selecting the ideal motor for your application.
Types of Motors Used in Drones
Brushless DC (BLDC) Motors
BLDC motors are the most widely used motors in modern drones. They are characterized by:
Electronic commutation: No brushes are used, reducing friction and wear.
High efficiency: Converts energy to motion with minimal loss, extending battery life.
Precise speed control: Enables smooth hovering, accurate flight paths, and stable operation.
Low maintenance: Long-lasting with minimal upkeep requirements.
These features make BLDC motors ideal for consumer drones, industrial UAVs, and professional photography drones.
Brushed DC Motors
Brushed motors are typically found in toy drones and entry-level models due to their low cost and simple control. However, they have notable limitations:
Shorter lifespan: Brushes wear out over time.
Lower efficiency: Energy loss through friction reduces flight time.
Limited precision: Less stable flight compared to brushless motors.
Brushed motors are suitable for micro or beginner drones but are rarely used in high-performance applications.
Electronically Commutated (EC) Motors
EC motors are similar to BLDC motors but often used in specialized industrial drones. They combine electronic commutation with optimized control for:
High efficiency
Low noise operation
High torque output for heavy-lift drones
Key Factors to Consider When Choosing a Drone Motor
Selecting the right motor requires evaluating the drone’s design and intended use. Consider the following factors:
Thrust-to-Weight Ratio: Ensure the motor can generate sufficient lift for the drone’s total weight, including payload.
Battery Compatibility: Motors must match the drone’s voltage and current specifications to avoid underperformance or overheating.
Flight Purpose:
Racing drones need high-speed, responsive motors.
Surveying or photography drones prioritize stability and longer flight duration.
Efficiency and Flight Time: High-efficiency motors reduce energy consumption, allowing longer flights without increasing battery size.
Environmental Conditions: Outdoor drones may require motors resistant to dust, humidity, and temperature changes.
Noise Levels: Low-noise motors improve user experience, particularly in residential or sensitive environments.
Practical Tips for Motor Selection
Choose BLDC motors for most consumer, commercial, and industrial drones.
Match propeller size and motor Kv rating to the desired speed and torque.
Consider durability and maintenance requirements, especially for professional applications.
Test motor performance under real load conditions before finalizing your design.
In today’s drone industry, BLDC motors dominate due to their efficiency, stability, and long lifespan. While brushed motors and EC motors have niche applications, selecting the right BLDC motor ensures optimal flight performance, precise control, and extended battery life.
Understanding your drone’s specific needs—weight, speed, payload, and operational environment—is crucial for choosing the most suitable motor, which directly impacts reliability and flight experience.