Starting of DC Motors
At the moment a DC motor is started the armature is stationary and there is no counter EMF being generated. The only component to limit starting current is the armature…
Series-Wound Motor
Since the armature and field in a series-wound motor are connected in series, the armature and field currents become identical, and the torque can be expressed as shown in below…
Shunt-Wound Motor Operation
The speed-torque relationship for a typical shunt-wound motor is shown in Figure 8. A shunt-wound DC motor has a decreasing torque when speed increases. The decreasing torque-vs-speed is caused by…
DC Motor Connections
There are various types of DC motors found in industry today. Each type contains various characteristics that makes it desirable for certain applications. DC Motor Connections The below Figure shows…
DC Motor Speed
The field of a DC motor is varied using external devices, usually field resistors. For a constant applied voltage to the field (E), as the resistance of the field (Rf)…
Generator Action in a Motor
A generator action is developed in every motor. When a conductor cuts lines of force, an EMF is induced in that conductor. Current to start the armature turning will flow…
DC Motor Torque
Torque is defined as that force which tends to produce and maintain rotation. The function of torque in a DC motor is to provide the mechanical output or drive the…
DC Motor Theory
DC motors are widely used to drive various equipment. The speed and torque produced in a DC motor depends on a variety of factors. Inducing a Force on a Conductor…
Compound Generators
Series-wound and shunt-wound generators have a disadvantage in that changes in load current cause changes in generator output voltage. Many applications in which generators are used require a more stable…
Series-Wound DC Generators
When the field winding of a DC generator is connected in series with the armature, the generator is called a series-wound generator (Figure 10). Figure 10a :Â Series-Wound DC Generator…
