A brushless motor with three coils on the stator will have six wires (two per coil) extending from these coils. In most embodiments, three of these wires will be connected internally, and the remaining three wires will extend from the motor body (as opposed to the two wires that extend from the brushed motor as described earlier). Compared with connecting only the positive and negative terminals of the power unit, the wiring in the brushless motor housing is much more complicated.
Effectiveness
Because these motors can be continuously controlled with the maximum rotational force (torque). In contrast, brushed motors only reach their maximum torque at certain points of rotation. In order for the brushed motor to provide the same torque as the brushless model, a larger magnet is required. This is why even small brushless motors can provide considerable power.
Controllability
The feedback mechanism can be used to control the brushless motor to accurately transmit the required torque and speed. Precise control can reduce energy consumption and heat generation, and can extend battery life when the motor is powered by a battery.
The brushless DC motor system can provide electronic input control, and the driver can be directly connected to the programmable controller. Since the motor does not require a power relay, there is no need for regular maintenance or replacement of the relay, which makes the machine very reliable. Moreover, the time required to set up the motor is greatly reduced.
Due to the lack of brushes, brushless motors also have high durability and low electrical noise generation. For brushed motors, the brushes and commutator are worn out due to the contact of continuous movement, and sparks are also generated during contact. Especially when the brush passes through the gap of the commutator, strong sparks and electrical noise are easily generated. This is why brushless motors have more applications in avoiding electrical noise.
Save space
The compact but powerful brushless DC motor has permanent magnets in the motor rotor. Compared with an AC motor with a frame size of 3.54 inches (90 mm), the brushless DC motor of the same specification is 2.95 inches (75 mm) shorter and the output power is 1.3 times the original.
The compact motor structure allows you to reduce the size of the equipment.
Energy saving
Brushless DC (BLDC) motors are equipped with permanent magnets in the rotor, so the secondary losses generated by the rotor are very small.
For example, under the output power of 1/12 HP (60 W), the power consumption of BLM series brushless DC motors is about 23% less than that of inverter-controlled AC motors, thus realizing energy-saving operation.
No brush = no maintenance
Brushless DC motors (BLDC motors) do not use brushes, which often require replacement and/or maintenance, thus saving time and costs.
