When it comes to DC Motors we find lots of varieties in the market. Each type is useful for performing a special task. Thanks to the wide popularity and usage of dc motors, thousands of companies built millions of motors each year and it became much easier for folks like us to choose one when we have such a wide range of beauties.
Here we will be discussing a few of them. Keep in mind one thing this classification is based upon different kinds of functions rather than sizes and structures.
• Permanent Magnet DC Motor or PMDC Motor
• Separately Excited DC Motor or SEDC Motors.
• Self-Excited DC Motor.
The Permanent Magnet DC Motor of pmdc motors are built with same structure just like an ordinary motor but it may not have the field windings. The main difference between Permanent Magnet Dc Motor and other types of the motor is just the types of magnet used. In PMDC Motors, we use a pair of permanent magnets to operate it.
The shaft of the motor rotates by electrical means due to the change in magnetic flux created by the magnets that in turn provides us with mechanical power. If you want to see an example of PMDC motor then you just need to crack down a simple toy car and the motor that you will obtain by this action will be a Permanent Magnet Brushed Dc Motor.
In the case of Separately Excited DC Motor the supply of direct current is divided into two parts and both the main parts of the motor receive separate supply of current. The field windings and armature have their own different supplies of direct electric current. The torque produced in the motor can only be changed by changing the flux rather than the current supply.
In a self-excited dc motor, the field windings are connected in parallel or in series to the armature windings or partly in parallel and partly in series. Depending upon this properties these motors are further divided into three main categories.
• Shunt Wound Self-Excited DC Motors- windings are connected in parallel to armature.
• Series Wound Self-Excited DC Motors - windings are connected in series with armature.
• Compound Wound Self-Excited DC Motors windings are partly in series and partly in parallel combination with respect to armature.
Article Number: 51104