Brushed vs Brushless DC motor

[ramonegumpert]

Dear Sirs/Mdms,

I would like to find out how different is a brushed vs brushless dc motor in terms of size, weight and power .

I can find articles on the net regarding some comparisons between the 2 types. For example, a brushed is less efficient than a brushless motor.

But i cannot find info about :

1. Assuming a brushed and a brushless motor both are of the same size and weight,
which is more powerful in terms of torque produced?

I suspect the brushed motor is less powerful as it is less efficient dues to contacts and frictional losses?

2. Between these 2 types of motor of same dimensions, does a brushed motor have any advantage over the brushless motor?

sincerely,
Ramone

 

[Bob S]

Hello ramone-
One specific advantage a brushless permanent magnet dc motor with a Hall Effect sensor has over a brushed motor is being able to run as a torque motor, at very low or zero RPM, because in a brushed motor there is the danger of damaging the commutator.
Bob S

 

[oswaler]

Dear Ramone,

Thank you for your inquiry regarding the differences between brushed and brushless DC motors. I am happy to provide you with some information on this topic.

Firstly, let me explain the main difference between these two types of motors. A brushed DC motor uses a mechanical commutator to switch the direction of current flow, while a brushless DC motor uses electronic commutation. This means that a brushed motor has physical contacts that can wear down over time, leading to reduced efficiency and potentially lower power output compared to a brushless motor.

To answer your first question, assuming both motors are of the same size and weight, the brushless motor will typically produce more torque than the brushed motor. This is due to the absence of physical contacts and frictional losses in the brushless motor, allowing for more efficient transfer of electrical energy into mechanical energy.

As for your second question, there are some advantages of a brushed motor over a brushless motor in certain applications. For example, a brushed motor is generally less expensive and easier to control compared to a brushless motor. It also has a simpler design, making it more suitable for low-power applications. However, in terms of overall efficiency and performance, a brushless motor is typically the preferred option.

I hope this information helps to answer your questions. For further reading, I recommend looking into the differences in construction, operation, and applications of brushed and brushless DC motors.

Best regards,