Advantages and Disadvantages of Brushed DC Motors vs. Brushless DC Motors

# English Translation To understand their working modes, advantages, disadvantages, etc., more intuitively, a comparative analysis is provided below. ## Structural Difference The term "brush" in brushed and brushless refers to carbon brushes. The key difference between brushed DC motors and brushless DC motors is whether they are equipped with common carbon brushes and commutators (i.e., commutation via brushes and commutator or via inverter circuit).   In brushed DC motors, commutation is always achieved through contact between graphite carbon brushes and a ring-shaped commutator mounted on the rotor. In brushless DC motors, Hall sensors feed back the rotor position to the control circuit, enabling it to determine the commutation timing of the motor phases—this is known as electronic commutation. ## Working Principle - Brushed motors use **mechanical commutation**: magnetic poles are stationary, while coils rotate. - Brushless motors use **electronic commutation**: coils are stationary, while magnetic poles rotate. ## Comparison of Advantages and Disadvantages ### ① Brushed DC Motors **Advantages**:   The biggest advantage is **simple control**; no complex driver is needed, and it can run directly when connected to a DC power supply. Speed can be adjusted via simple resistance division or voltage variation.   Cost is low, with mature manufacturing processes and no need for expensive electronic controllers. **Disadvantages**:   High noise; carbon brushes wear continuously, with a typical lifespan of only several hundred to several thousand hours (short service life). For industrial equipment, this requires regular shutdown maintenance.   Electromagnetic interference (EMI) is significant, as sparks occur during commutation. This not only causes serious radio interference but also prohibits use in flammable and explosive environments. ### ② Brushless DC Motors **Advantages**:   Long service life; no physical contact brushes, so nearly maintenance-free.   Quiet operation and low electromagnetic interference.   Capable of achieving extremely high rotational speeds. **Disadvantages**:   The electronic controller required is expensive.   Complex drive circuits are needed.   Additional position sensors are required.