With the growing popularity of efficient brushless motors, replacing AC motors with these motors brings several advantages. In this blog post, we will uncover one of the advantages that can benefit lighter and compact equipment designs. If we just look at the motors, brushless motors are much more power efficient than AC induction motors. This means a smaller brushless motor can do the work of a bigger AC motor. With recent trends in efficiency, brushless motors should be considered during the motor selection process for new designs.
An ideal application example is shown below with a grip conveyor that has two belts on either side, driven by two AC induction motors. AC motors are not the most efficient option when it comes to power-to-torque conversion. Therefore, the motors need to be bigger and heavier than they really need to be.
CHALLENGE Reduce conveyor mass for easier handling & installation
Conventional Equipment: Grip conveyor with two belts on each side driven by two AC gear motors. An inverter (VFD) is typically used for speed control (not shown).
Problems with Conventional Equipment:
SOLUTION BMU Series brushless gear motor + AC input driver
Use a compact and high power
Advantages offered by BMU Series:
| Oriental Motor AC Induction Motor | BMU Series | |
| Output Power | 90 W (1/8 HP) | 60 W (1/12 HP) |
| Frame Size | □ 90 mm (3.54") | □ 80 mm (3.15") |
| Gear Type | Parallel Shaft | Parallel Shaft |
| Gear Ratio | 9:1 | 30:1 |
| Permissible Torque | 4.2 N·m (37 lb-in) | 5.2 N·m (46 lb-in) |
| Mass | 4.7 kg (10 lbs) | 1.4 kg (3 lbs) |
RESULT: The mass can be reduced by 6.6 kg (3.3 kg per unit)
Because of feedback control, brushless motors also offer much better speed regulation than AC induction motors. Read the next post to see how to synchronize the two belt speeds.