Brushed motors were introduced in the 19th century with the invention of solid-state electronics technology. Brushed motors were the first equipment to produce mechanical energy with the help of electrical energy. A DC power was required to operate a brushed motor. The name brushed motors were given to such motors as these motors used a brush in its components for rotation. The structure of a brushed motor includes being armature, brushes, a commutator, a field magnet, and an axle. The structure for a brushed motor is shown in the figure below.
The brushes used in the brushed motors are used for the rotation of the commutator. The brushes used help to rotate the commutator in the opposite direction as compared to the permanent magnet polarity. To change the direction for the rotation of the motor, the polarity for the brushed is changed. Similarly, by reversing the polarity of the battery attached with the motor the direction for the rotation of the motor is also changed.
Different properties linked with the brushed motor are determined and estimated with the help of different materials used in the structure of the motor. The speed of the DC brushed motor is changed by changing the voltage value which is provided as the input to the motor. The speed of the motor is also changed by changing the magnetic field of the motor. Different kinds of stators with permanent magnet are also used in the brushed DC motors for the rotation purpose of the motors. For the big level industrial brushed motors rotor magnets are used.
The applications of brushed motors are numerous as they are used daily in different appliances and equipment. The brushed motors with permanent magnets are mostly used. These motors are used in the equipment demanding specific horsepower which includes different domestic and industrial appliances. Small dc brushed motors are also hugely used in toys and small robots.
As the name suggests, the brushless motors are the motors without brushes. The design of the brushless motors is more sophisticated as compared to the brushed motors. Permanents magnets are mounted in brushless motors. The number of mounted permanent magnet in brushless motors varies from the brushless motor to motor. A rotor is the main component in the brushless motors and the magnets are used only to drive the rotor. The structure and components of a brushless motor are shown in the figure below.
The brushless motors are also known as the electronically commutated motors and synchronous motors. The brushless motors are powered with the help of DC power but inside the brushless motors, an inverter is used which converts the dc power into ac which is used in the rotation of each phase of the motor.
Brushless motors are used in every field of life due to their efficiency and reliable control. From the complex medical equipment to drones and complex robots, brushless motors are used.
A comparisition between Brashed motors and Brushless motors by topic:
Year of invention
Brushed motors were invented in between 1800
Brushless motors were invented in 1960
Brushed motors: Commutator used in brushed motors has different engineering disadvantages such as friction, replacement of brushes.
Brushless motors: The commutator from brushless motors was replaced by the servo system.
Brushed motors: Conversion of electrical power into mechanical power by brushed motors is not efficient.
Brushless motors: Conversion of electrical power into mechanical power by brushless motors is efficient as compared to brushed motor
Brushed motors: The overall efficiency of the brushed motors is also less as compared to the brushless motors.
Brushless motors: The overall efficiency of the brushless motors is also greater as compared to the brushless motors.
Brushed motors require a proper maintenance in order to keep them efficient in terms of performance.
Brushless motors are maintenance free motors with high speed as compared to brushed motors.
Brushed motors: The working efficiency of the high-quality brushed motors is comparable to a low-quality brushless motors.
Brushless motors: The working efficiency of the high-quality brushless motor is much better than a high-quality brushed motor.
Connection with Battery/ Power Supply
Brushed motors are easily connected to the battery or power supply.
Brushless motors are connected to the power supply with a proper mechanism and polarity.
Brushed motors are less expensive as compared to brushless motors.
Brushless motors are costly as compared to the brushed motors.
Brushed motors efficiency is about 75-80%.
Brushless motors efficiency is about 85-90%.