Question

What is the formula for the voltage across each field coil?

(a) voltage across each field coil = field current * resistance of each field at 75°C

(b) voltage across each field coil = field current / resistance of each field at 75°C

(c) voltage across each field coil = field current + resistance of each field at 75°C

(d) voltage across each field coil = field current – resistance of each field at 75°C

This question was posed to me in class test.

I'd like to ask this question from Design of Field Winding in chapter Design of Synchronous Machines of Design of Electrical Machines

Answer 1

Right answer is (a) voltage across each field coil = field current * resistance of each field at 75°C

Easiest explanation: The field current is first calculated from the machine. Next the resistance value of each field at 75°C is calculated and this gives the voltage across each field coil.