Brushless DC Motor: A Motor to Satisfy Needs of Positioning

Posted by Jack Wang on November 6th, 2015

When choosing an efficient motor for your needs, the brushless DC motor is one of the things that you are likely to come across. Most machine designers and engineers prefer Brushless DC motors for specific types of applications, including positioning and material handling. 

What exactly are brushless DC motors and how do they work? 

Brushless DC motors are also known as BLDC motors (or EC / ECM motors especially in HVAC industries) are electric motors that are operated by using an electronic commutation system which is generated by brushless motor driver. Unlike their brushed motor counterparts, brushless DC motors work doesn’t need any carbon brushes to commute, that is, to alter the direction of the current flowing in the wingdings. This feature gives brushless motor lots of nice advantage over brush type dc motors. 

What are their applications in positioning and material handling systems? 

The industrial engineering applications of Brushless DC motors primarily focus on industrial automation design and manufacturing engineering. In the state of art manufacturing facility, these motors are popularin automated assembly line and industrial robots. Brushless servo or steppers are used to position a certain tool for a manufacturing process or a certain part for assembly, such as painting or welding. Brushless motor servo system might need larger initial investment than stepper servo system, however brushless motors supreme dynamic characteristic and the ability to maintain a high rpm (up to 20000 rpm to 30000 rpm) under the high torque (eg: 10Nm or 1400 Oz-in) load on the shaft make the brushless motor worth the investment. 

Why use Brushless DC motors? 

There are many reasons that using Brushless DC motors is become popular in the field where brushed dc motors used to be dominate. The first reason is that the brushless dc motors doesn’t contain a brush, which makes the BLDC motor more reliable, longer lifetime, lower maintenance, lower noise and no electric sparks. Also, the lack of brushes make the high speed brushless motor possible. Their speeds can go beyond 15,000 rpm very easily without worrying about the wear out of brushes or other mechanical parts. Brushless dc motors have longer life expectancies, usually more than 10,000 hours.   High-quality brushless motors are capable of operating with minimal electromagnetic interference and noise compared to brushed motors. 

Other applications 

Brushless DC motors can be applied to a wide range of devices and equipment. In fact, most of application that uses a brushed DC motor can be replaced with a brushless version. Brushless motors can be found in medical instrument, DVD players, electric cars, robotics, material handling, electro-hydraulic actuators and cooling fans for PCs etc. They are capable of generating high torque with a very compact size, making them perfect for things like modern aircraft. Also, with the custom design, the brushless DC motors can work with different voltages, so on the market you can find 12v/24v/36v/48v brushless DC motors very easily. 

Brushless DC motors are more advanced than traditional motors because of their low-friction operation, which generates less heat and will makethe small power tools using BLDC motors last longer. With less heat, power tools will tend to have longer battery life, at up to 50 percent more than when they run with traditional motors. Moreover, tools can have enhanced performance and greater power due to better power transfer ratio and overall higher efficiency of brushless DC motors.

About the Author: 

This article is written by Jack Wang who is associated with GEMS Motor. Jack got his Bachelor's degree in Mechanical Engineering and Master's degree in Electrical Engineering, specialized in electric motor design and motor driver development. Jack was born in greater Shanghai area, China, and had several years of study and work experience in the United States. With the deep knowledge of electric motors and great bilingual skills in Mandarin and English, Jack helps market our electric motor products worldwide. Jack currently holds the position of Director of Marketing at GEMS Motor.