2) Explain, using diagrams, armature reaction in a dc motor, the effects it has on the motor and methods to reduce it.
Explanation:
DC motor: A DC motor is any class of electrical machines that converts direct current electrical power into mechanical power. The most common types rely on magnetic fields.
Armature: The part of an electrical motor or generator that produces an electric current when it turns in a magnetic field.
Magnetic flux: Magnetic flux is the number of magnetic field lines (also called as magnetic flux density) passing through A closed surface such as conducting coil. The SI unit of magnetic flux is the weber(Wb).
So in this case, a DC motor, two sorts of magnetic(attractive) fluxes are available, ‘armature flux’ and ‘primary
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The armature flux superimposes with the primary or main field flux and, henceforth, aggravates the fundamental field flux (as appeared in third figure of above picture). This impact is called as armature reaction in DC motors.
The adverse effects of Armature Reaction
The effect of armature reaction is well illustrated in the figure below
1) Armature response debilitates the principle flux. If there should arise an occurrence of a DC generator, weakening of the fundamental flux lessens the produced voltage.
2) Armature response mutilates the fundamental flux, subsequently the position of M.N.A. gets moved (M.N.A. is opposite to the flux lines of fundamental flux). Brushes ought to be set on M.N.A., else, it will prompt starting at the surface of brushes. Thus, because of armature response, it is difficult to decide the precise position of M.N.A.
3) For a loaded DC generator, MNA will be moved toward the pivot (direction of rotation). Then again, for loaded DC motor, MNA will be moved in the course inverse to that of the rotation.
Methods to reduce
2. Now the belt is turning. This makes the secondary clutch turn, which causes the track to turn and the snowmachine to move forward.
The experiment test-bed is composed of a DC motor, an engine, a chain drive, a shaft and other accessorial components. The DC motor is used to drive the engine shaft and its speed can be up to 1450 r/min.
The motor is turned on, the lower part begins turning its belt. The belt is made of rubber so it attracts more electricity than a regular belt would. The lower part builds to have a negative charge and the belt makes a positive charge. The reason this happens is because in the belt there is a silicon part that is built in the belt making it more negative than rubber, the lower part is taking electrons from the belt as it goes over the roller. Causing the electricity to go up into the sphere and flowing through it.
...late 17th century, and beginning of the 18th century, transportation was favored by American society so much, the wealthier would hire chauffer’s to take people places. So not only did the motor produce a better and more efficient life style, it also created a huge business industry, as we know it today called, “valeting”. The actual motor worked like this. “Two cups filled with mercury would contain a magnet and a wire with one being fixed and the other free to move. Whenever a current was passed through the wire, the free moving magnet or wire would revolve around its fixed partner due to the electromagnet forces being produced.” (History of Innovation). This first motor was a prime example of the fact that movement could be created by electricity and electricity could be created by friction. This motor was the most useful and applicable invention in the 1800’s.
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