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The open circuit terminal voltage versus the field current (open circuit characteristics) for a separately excited dc

Posted: Sun May 15, 2022 2:20 pm
by answerhappygod
The open circuit terminal voltage versus the field current (open circuit

characteristics) for a separately excited dc generator driven at 1000 rpm is

given below:

𝑰𝒇

(A) 0 0.1 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2

𝑬𝒈(V) 12 16 30 55 75 90 100 110 115 120 122 123

Assume the machine is connected as a shunt generator and driven at 100

rpm and has a field resistance of 100Ω,

a. Use excel spreadsheet to draw the open circuit characteristics from the

given data

b. Determine the open circuit voltage and exciting current of the shunt

generator

c. Find the critical resistance with the help of the graph

d. Find the resistance to induce 105V with the help of the O.C.C.