Brushless Dc Motors and Their Applications
A BLDC motor or Brush-Less DC motor is an Electronically Commutated Motor (ECM) or a synchronous motor that uses the electrical power supply of DC (Direct Current). Brushless DC motors comprise of rotors in the form of permanent magnets and stators in the form of windings of the polyphase armature.
DC motors are used for a wide array of applications that feature a high level of starting torque and a capacity to rotate at high speeds. They come in varieties of brushed and brushless motors. BLDC motors are quieter than Brushed motors with low maintenance and longer life.
What are DC motors?
DC motors are electric motors powered by Direct Current. They feature qualities like rotation at high speed and the capacity to deliver a torque of high starting. The torque and speed of the motor are controlled by the drive voltage.
Such motors can be distinguished into Brushed DC motors and brushless DC motors. This is based on whether they are using brushes as an electrode. The Brushed motors have a shorter shelf life since they are equipped with commutators and brushes, both of which are consumable parts.
On the other hand, the BLDC motor lacks brushes, as the name itself suggests. Instead, such motors are driven by turning off the transistor in the drive circuit in on or off modes depending on a signal emerging from a magnetic sensor within the motor.
Since BLDC motors avoid making use of consumable brushes and feature electronic switching of current flow, they are low maintenance and last long. Another highly attractive feature is that they are much quieter than Brushed motors. Such low noise levels make them popular for frequent use in electronic household devices as well as other equipment needing low noise.
Applications of BLDC motors
- Home appliances and consumer durables
Though it is tough to observe BLDC motors in action in daily life, they are frequently found within home appliances of common use. Common examples include refrigerators and air-conditioners. Such appliances deliver warm or chilled air using fans. BLDC motors are typically used to power such fans.
Also, BLDC motors are being used more and more to power electric fans. The household fans feature blades that rotate fast and tend to generate much noise. Hence, BDLC motors are widely used to run models that showcase quiet operation as well as fine and simplified adjustment of power.
Yet another application of such motors is in the case of electrical products of commercial use. Instances are feeding of paper in laser printers, controlling propellers in drones, turning of saws and screwdrivers in power tools. In sum, BLDC motors are highly versatile.
- Precision devices
BLDC motors are used widely in precision devices. Main examples include hard drives of DVD devices, computers, and Blu-ray recorders. A crucial function in such devices is disk rotation. BLDC motors are utilized in spindles that rotate the disks.
The majority of daily applications of this kind mandate a long life of the product. Because of low maintenance needs and long life, BLDC motors have carved a special role in the industry for precision devices.
- Automotive industry
It may be noted that the use of BLDC motors is expanding with every passing day. This growth is most pronounced in the automotive industry. Driving a car involves the application of a wide array of electronic devices. Some of the applications are motors for power steering, motors for oil distribution, motors for head-lamp levelling, motors for electric brakes, motors for electric stabilizer, motors for automatic manipulation of hatches, motors for door locks, and fan motors for seat cooling.
Driving vehicles is risky for drivers and passengers as well as for pedestrians and other users of roads. BLDC motors, with their low maintenance and long life, are used in applications to minimize such risks. Additionally, the quiet operation of such motors helps offer a more relaxing environment for driving.
- Industrial engineering
The use of BLDC motors in this sector focuses mainly on the design of industrial automation or manufacturing engineering. In the arena of manufacturing, BLDC motors are used mainly for actuation systems, positioning, and motion control.
BLDC motors are well suited for applications in manufacturing due to their great speed-torque features, high power density, a wide range of speeds, low maintenance, and high efficiency. The most popular use of BLDC motors in industrial engineering is for industrial robots, servo motors, linear motors, CNC machines, and extruder motors.
- Aeromodelling
BLDC motors have become popular for use in making model aircraft, such as drones and helicopters. The wide array of available sizes and attractive power-to-weight ratios has transformed the market for model flights that are electrically powered and have virtually banished the use of brushed motors in such applications.
BLDC motors have eliminated engines of internal combustion, which were used to power heavy models of aircrafts, and replaced them with lightweight and simple models of electric aircrafts. They have reduced noise pollution linked to model aircraft.
In sum, all can look forward to wider applications of Brushless DC motors in the future. From powering drones to robots, they are the motors of the future.
