EC Motors Versus Brushed DC Motors
:
Brushed DC
| Rotor | Windings and commutator |  |
|---|---|---|
| Stator | Permanent magnets and brushes | |
| Motor voltage | DC voltage at 2 wires |
EC
| Rotor | Permanent magnets |  |
|---|---|---|
| Stator | Windings ; Hall sensors | |
| Motor voltage | PWM DC voltage from driver circuitry ; 3 phases |
Applicational Notes
| No brushes | No wear of brushes No sparkling No surface contact issue |
High lifetime (only bearing life) Low noise Low Electromagn. Interference EMI High reliability Less sensitive to ambient pollution High speed possible |
|---|---|---|
| Magnets in rotor | Lower rotor inertia than DC motor | Fast acceleration – highly dynamic |
| Windings in stator | Windings in contact to housing – good heat transfer | High power/size ratio |
| No commutator | Shorter rotor 20…30% | High power/size ratio |
| Driver circuitry Hall sensors |
Additional costs | Total costs higher than brushed DC motor
Exception: For speed control, brushed DC needs driver circuitry + possibly sensors too |