DC Motors Types And Applications

DC  motors converts direct current into rotary movement of it amature.

The RPM(revolution per second) of these motors depends on it construction and winding coil.

Generally DC motors can only exit in two forms namely, brushless and brushed motors.

• Brushed motors: These type of motor's armature is connected to external circuits or power by means of graphite brushes. The armature contacts is made to slip over the brushes, so it wear over time and needs to be replaced. Heavy power DC motors are usually brushed, like those used in factories, miling machines and trains.

• Brushless motors: Their armature is connected to external power or circuits by means of wooly sheets of brass or steel. More advanced types have their coil as the stator and the magnet as the rotor thus eliminating the need of brushes. They don't need to be replaced as their is no much wear and tears. Low power motors running on 1.5v to 48v are usually brushless.

Direct current motors are classified based on their coil and magnet construction, here are the types.

1. Shunt DC motor.

It's magnetic field is provided by electromagnets. The armature is connected in parallel with the laminated core electromagnet producing the magnetic flux.

It has a great speed regulation due to the fact that it shunt field can be excited separately.

2. Permanent magnet DC motor.

This type of motor uses permanent magnets to produce magnetic flux on the armature. 

It has a great starting torque and controlling high speed which depends on the amount of current applied to it. However, the magnet tends to loose it magnetising power over time. Low power motors are usually composed of  permanent magnets, an example is shown above.

3. Series DC motors.

The filed coil made with few thick turns of copper wire also known as an electromagnet which produces the magnetic field is connected to the armature in series.

It has a large amount of starting torque, but can't regulate it speed, moreover it can be damaged when it's running with no load.

4. Compound DC motors.

It is the combination of shunt and series DC motors characteristics. 

It's made of two magnetic field coils, with one connected in series with the armature and the other one connected in parallel.

It has more advantages than the shunt and series type because it speed is controllable, has a great starting torque, has high speed and it direction of rotation is easily reversible while in operation.

Appllications of DC motors.

DC motors have wide applications and have much advantages than AC motors due to it controllable speed and reversing abilities. This  have increased it popularity in control systems, dynamic braking systems and high speed machines.

They are use in electric trains, driving conveyor belts,drones and robots.