Question

In 3-Φ Semi-controlled rectifier calculate the average value of the voltage if the supply is 440 V and firing angle is 22°.

(a) 571.5 V

(b) 572.8 V

(c) 548.3 V

(d) 524.1 V

I have been asked this question by my college professor while I was bunking the class.

This intriguing question comes from Solid State Controlled Drives in division Introduction to Solid State Controlled Drives of Electric Drives

Answer 1

Right option is (b) 572.8 V

To explain: In 3-Φ Semi-controlled rectifier, the average value of the voltage is 3Vml(1+cos(∝))÷2π=3×440×√2(1+cos(22°))÷6.28=572.8 V.