A 100KW, 250 V, 400 A, a long shunt compound generator has an armature resistance of 0.025 ohms. There are 1000 shunt fields turns per pole and 3 series field turns per pole. The series field is connected in a such a fashion that positive armature current produces direct-axis MMF which adds to that of the shunt field. Compute the gross MMF at the rated terminal current when shunt field current is 4.7A and speed is 1150 rpm.

DC Machines topics are: DC machine applications and its circuit models, mmf and flux density waveforms in DC machines, methods of excitation, efficiency and testing of dc machines. DC machines, which can be classified as DC motors and DC generators, convert mechanical energy into electrical energy. They contain AC currents and voltages, but convert AC voltage to DC voltage. DC machines are used in applications where high starting torque and accurate speed control over a wide range are important.  Here are some types of DC machines: DC motors: Use direct current to produce mechanical force.... Show more

DC Machines topics are: DC machine applications and its circuit models, mmf and flux density waveforms in DC machines, methods of excitation, efficiency and testing of dc machines.

DC machines, which can be classified as DC motors and DC generators, convert mechanical energy into electrical energy. They contain AC currents and voltages, but convert AC voltage to DC voltage. DC machines are used in applications where high starting torque and accurate speed control over a wide range are important. 

Here are some types of DC machines:
DC motors: Use direct current to produce mechanical force. DC motors can vary in size and power from small motors in toys and appliances to large mechanisms that power vehicles, pull elevators and hoists, and drive steel rolling mills.
Shunt DC generators: Mainly used for lighting purposes, charging batteries, and supplying field excitation current to alternators.
Compound motors: Used where higher starting torque and fairly constant speed is required. Examples of usage of compound motors are in presses, shears, conveyors, elevators, rolling mills, and heavy planners. 

Other types of DC motors include:
Series DC motor
Permanent magnet DC motor 

DC machines have two main parts:
Stator: Contains parts such as brushes, magnets, and housing for the whole motor
Rotor: Contains the windings, the communicator, and the output shaft 

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