Question

Calculate the line voltage in the delta connection when phase voltage=45 V.

(a) 46 V

(b) 47 V

(c) 45 V

(d) 78 V

The question was posed to me by my college professor while I was bunking the class.

This interesting question is from Induction Motors in division Speed Control of Direct Current Motors & Induction Motors of Electric Drives

Answer 1

The correct choice is (c) 45 V

Explanation: The line voltage in case of delta connection is phase voltage. Line current leads the phase current by an angle of 30°. VL-L=Vph = 45 V.