Both the field coils provide for the required amount of magnetic flux, that links with the armature coil and brings about the torque necessary to facilitate rotation at desired speed.

As we can understand, a

So the compound wound DC motor reaches a compromise in terms of both this features and has a good combination of proper speed regulation and high starting toque.

Though its staring torque is not as high as in case of DC motor, nor is its speed regulation as good as a shunt DC motor. Overall characteristics of DC shunt motor falls somewhere in between these 2 extreme limits.

Now we know in shunt motor, And in series motor

Therefore, the current equation of a compound wound DC motor is given by And its voltage equation is,

But from the diagram above we can see, Since the entire supply current flows through the series field winding.

And like in the case of a DC shunt motor, Equation (2) and (3) gives the current equation of a short shunt compound wound DC motor.

Now for equating the voltage equation, we apply Kirchoff’s law to the circuit and get, But since Thus the final voltage equation can be written as, Apart from the above mentioned classification, a compound wound DC motor can further be sub divided into 2 types depending upon excitation or the nature of compounding. i.e.

The compounding characteristic of the self excited DC motor is shown in the figure below.

New Articles
Series and Parallel Inductors Electric PowerMeasurement of LossShunt ReactorIR MeasurementAmpere's Circuital LawClosely Related Articles
Types of DC MotorDC Shunt MotorDC Series MotorDC Compound MotorPMDC MotorBrushless DC MotorsElectrical MotorWorking of MotorDC MotorSpeed Regulation of DC MotorSpeed Control of DC Motor DC Motor WorkingTorque in DC MotorConstruction of DC MotorTesting of DC MachineSwinburne Test of DC MachineLosses in DC MachineWard Leonard MethodArmature Reaction in DC MachineCommutation in DC MachineMethods of Improving CommutationStarting Methods for DC Motor3 Point Starter4 Point Starter
Articles Categories
Basic Electrical Technology
Circuit and Network Theories
Electrical Laws
Engineering Materials
Battery Technologies
Illumination Engineering
Electrical Power Generation
Electrical Power Transmission
Electrical Switchgear
Electrical Protection
Electrical Measurement
Control System
Electrical Transformer
Electrical Motor
Induction Motor
DC Motor
Synchronous Motor
Electrical Generator
Electrical Drives
Electronics Devices
Power Electronics
Digital Electronics
Questions
MCQ