CHAPTER II 

 SYNCHRONOUS GENERATORS 



1. With normal excitation the resultant air-gap flux in a 60- 

 cycle alternator is 10 6 lines per pole. The flux density is con- 

 stant under the pole face and is zero between the poles. 



If the ratio of pole arc to pole pitch is 0.75 and the coil pitch 

 is 1.0, what is the generated armature voltage per turn? What 

 is the form factor of this e.m.f.? Sketch the graphs of the 

 flux density and the e.m.f. 



2. In problem 1 if the ratio of pole arc to pole pitch is 0.75 and 

 the coil pitch 0.67, what is the generated armature voltage per 

 turn? What is the form factor of this e.m.f.? Sketch the 

 graphs of the flux density and the e.m.f. 



3. In problem 1 if the ratio of pole arc to pole pitch is 0.5 and 

 the coil pitch is 1.0, what is the generated armature voltage per 

 turn? What is the form factor of this e.m.f.? Sketch the 

 graphs of the flux density and the e.m.f. 



4. With normal excitation the resultant air-gap in a 60-cycle 

 alternator is 10 6 lines per pole. The flux density is constant under 

 the pole face and decreases uniformly to zero at points midway 

 between the poles. 



If the ratio of pole arc to pole pitch is 0.75 and the coil pitch 

 is 1.0, what is the generated armature voltage per turn? What 

 is the form factor of this e.m.f.? Sketch the graphs of the flux 

 density and the e.m.f. 



5. In problem 4 if the ratio of pole arc to pole pitch is 0.75 

 and the coil pitch is 0.67, what is the generated armature vol- 

 tage per turn? What is the form factor of this e.m.f.? Sketch 

 the graphs of the flux density and the e.m.f. 



6. In problem 4 if the ratio of pole arc to pole pitch is 0.5 and the 

 coil pitch is 1.0, what is the generated armature voltage per turn? 

 What is the form factor of this e.m.f.? Sketch the graphs of the 

 flux density and the e.m.f. 



7. With normal excitation the resultant air-gap flux in a 60- 

 cycle alternator is 10 6 lines per pole. This flux is sinusoidally 

 distributed along the air-gap. 



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