Brushed DC Motor Basics Ⅳ

Now let us take a look at the different types of brushed DC motors.

Four Types of BDCMs
1. Permanent Magnet
2. Shunt - wound
3. Series - wound
4. Compound - wound
● Shunt + Series

There are four types of brushed DC motors.
The first type, is the Permanent Magnet Brush DC Motor. Second, the shunt-wound brushed DC motor. Third is the series-wound DC motor and fourth is the compound-wound brushed DC motor which is a combination of both the shunt and series wound brushed DC motors.

Permanent Magnet(PMDC)
- Most common
- Used in fractional horsepower applications
Examples: Toys, RC app., Slot cars, Appliances, etc…
- More cost effective than wound stators
- Torque, limited b/c of stator field
● Good low end ( low speed ) torque
● Limited high end ( high speed ) torque
- Responds very quickly to voltage changes due to constant stator field ( good speed control )
- Drawback, Magnets lose their magnetic properties over
time

  Permanent magnet brushed DC motors are the most common. These motors use permanent magnets to produce the stator field. They are generally used in applications needing fractional horsepower such as; Toys, Radio Control hobby applications, electric slot cars, appliances, etc. It is more cost effective to use permanent magnets than wound stators because they are cheaper to manufacture. The torque from a permanent magnet brushed DC motor is limited by its stator field, which gives it good low end ( low speed ) torque and a limited high end ( high speed) torque. The permanent magnet brushed DC motor responds very quickly to changes in voltage. This is due to its constant stator field, thus giving it good speed control capabilities. But, they do have a drawback. Permanent magnet brushed DC
motors will loose their magnetic properties over time, thus degrading its stator field and causing the motors performance to decline.