Question

A three-phase full converter is driving a DC motor. If a continues current of Im amperes is flowing through the motor load, then find the rms value of supply current drawn by the converter to drive the motor.

(a) Im/√2

(b) Im^2/3

(c) √2Im/√3

(d) √2Im/3

I had been asked this question in an internship interview.

I want to ask this question from Three Phase Converters-3 topic in portion Converters of Power Electronics

Answer 1

The correct choice is (c) √2Im/√3

To explain: The RMS value of the supply current IS over π radians would be

(IS)^2 = (1/π) x (Im)^2 x (2π/3) = Im√2/√3.