Simple Loop Generator Principle,Working

Simple Loop Generator Principle An electrical generator is a machine which converts mechanical energy (or power) into electrical energy (or power).The energy conversion is based on the principle of the production of dynamically (or due to motion) induced e.m.f.whenever a conductor cuts magnetic flux, dynamically induced e.m.f. is produced in it according to Faraday’s Laws of Electromagnetic...

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Skin Effect of Conductors In Transmission Lines

Skin Effect of Conductors In Transmission Lines When a conductor is carrying steady direct current (d.c.), this current is uniformly distributed over the whole X-section of the conductor. However, an alternating current flowing through the conductor does not distribute uniformly, rather it has the tendency to concentrate near the surface of the conductor as shown in Fig. This is known as skin effect in...

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Why We Can’t Store AC Voltages ?

Why we can not store AC like DC Before going to discussion on "why we can't store ac current in batteries" understand what is AC & DC voltages.AC voltage changes it's polarity 50-60 times per second (50Hz for India,UK & 60Hz for USA).But DC is constant voltage with respect to time.If we consider charging mechanism of electro-chemical cell or battery,it is continuous process of injecting electrons on negative...

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Brake Test on DC Shunt Motor:Efficiency By Direct Loading

In this method, the d.c. machine is loaded and output and input are measured to find the efficiency. For this purpose, two simple methods can be used. Brake test on dc machine:- In this method, a brake is applied to a water-cooled pulley mounted on the motor shaft as shown in Fig.(6.1). One end of the rope is fixed to the floor via a spring balance S and a known mass is suspended at the other...

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Sumpner's Test (Back to Back Test) on Transformer

Well, there are some methods to find out efficiency of transformers like OC & SC test on transformers,but they require direct loading on secondary.but in Sumpner's Test or Back to Back Test we apply phantom loading on transformer,so that we can save large amount of power from wasting. Direct loading means the transformer is to be loaded to its rated capacity for specified number of...

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E.M.F. Equation of a D.C. Generator

We shall now derive an expression for the e.m.f. generated in a d.c. generator. Let Ø= flux/pole in Wb Z = total number of armature conductors P = number of poles A = number of parallel paths = 2 ... for wave winding = P ... for lap winding N = speed of armature in r.p.m. Eg = e.m.f. of the generator = e.m.f./parallel path Flux cut by one conductor in one revolution of the armature, dØ = PØ webers Time...

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D.C. Machine Armature Windings

D.C. Machine Armature Windings The different armature coils in a d.c. armature winding must be connected in series with each other by means of end connections (back connection and front connection) in a manner so that the generated voltages of the respective coils will aid each other in the production of the terminal e.m.f. of the winding.This windings are same in both DC motor and DC generator. Two basic methods of making...

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