Please tell me in DETAIL about the following 3 types of fuses or recommend me a good power system protection book or a website link ? 1.Dropout Fuse 2.Striker Fuse 3.Empulsive fuse (not sure if its impulsive or explosion fuse , sorry)

why conductors of low tensile strength 1)produce greater sag and 2)can not be used for larger spans

Can Anyone Answer anyone of these ? Q1) why direct SOLUTION of Load Flow Studies in Not Possile ? Q2)Why majority of Buses in power system are load buses Q3)Why one of the buses in Power system is taken as reference bus (slack or swing) Bus ? Q4)Bus Admittance Matrix is a sparce (means it contains some zero elements ) matrix , give reason