Question

A single phase inverter gives rms value of output voltage as 115 V and the fundamental output voltage of as 103.5 V. Find the THD (Total Harmonic Distortion).

(a) 0.4 %

(b) 40.8 %

(c) 48.3 %

(d) 4.83 %

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I want to ask this question from Quality of Inverters in section Inverters of Power Electronics

Answer 1

The correct answer is (c) 48.3 %

To elaborate: Vr = 115 V and V1 = 103.5 V

THD =[ (Vr^2 – V1^2)^1/2/ V1 ] x 100 %.