Power Electronics (3140915) MCQs

MCQs of DC-AC converters – Inverters

Showing 31 to 40 out of 100 Questions
31.
A single phase full bridge inverter has RLC load. The dc input voltage is 230 V and the output frequency is 50 Hz. Find the expression for the load voltage up to the fifth harmonic.
(a) 292 sin 314t + 97.62 sin 314t + 58.57 sin 318t + 28.31 sin 318t + 3.686 sin 318t
(b) 292 sin 314t + 97.62 sin (3 x 314t) + 58.57 sin (5 x 318t)
(c) 292 sin 314t + 97.62 sin (2 x 314t) + 58.57 sin (3 x 318t) + 28.31 sin (4 x 318t) + 3.686 sin (5 x 318t)
(d) 292 sin 512t + 25.62 sin 249t + 6.74 sin 508t
Answer:

Option (b)

32.
A single phase full bridge inverter has RLC load with R = 4 Ω, L = 35 mH and C = 155 μF. The dc input voltage is 230 V and the output frequency is 50 Hz. Find the rms value of the fundamental load current.
(a) 28.31 A
(b) 20.02 A
(c) 16.69 A
(d) 26.90 A
Answer:

Option (b)

33.
A single phase full bridge inverter has RLC load with R = 4 Ω, XL = 11 Ω and XC = 20.54 Ω. The dc input voltage is 230 V. Find the value of fundamental load power.
(a) 1633 W
(b) 1603 W
(c) 1576 W
(d) none of the mentioned
Answer:

Option (b)

34.
A single phase full bridge inverter has RLC load with R = 4 Ω, L = 35 mH and C = 155 μF. The dc input voltage is 230 V and the output frequency is 50 Hz. Find the angle by which the third harmonic current will lead/lag the third harmonic output voltage.
(a) 67.25°
(b) 96.4°
(c) 49.87°
(d) 81.3°
Answer:

Option (d)

35.
Let Vs be the amplitude of the output voltage and P be the output power for a single-phase half bridge inverter. Then the corresponding values for a full bridge inverter would be
(a) 2Vs, 4P
(b) 2Vs, 2P
(c) Vs, P
(d) 2Vs, P
Answer:

Option (a)

36.
In VSI (voltage source inverters)
(a) both voltage and current depend on the load impedance
(b) only voltage depends on the load impedance
(c) only current depends on the load impedance
(d) none of the mentioned
Answer:

Option (c)

37.
The harmonic factor of nth harmonic is given by
(a) Vn
(b) V1/Vn
(c) Vn/V1
(d) None of the mentioned
Answer:

Option (c)

38.
____________ is the measure of the contribution of any individual harmonic to the inverter output voltage.
(a) THD
(b) Distortion Factor
(c) Harmonic Factor
(d) TUF
Answer:

Option (c)

39.
The Total Harmonic Distortion (THD) is the ratio of
(a) rms value of all the harmonic components to the rms value of the fundamental component
(b) average value of all the harmonic components to the rms value of the fundamental component
(c) rms value of all the third harmonic component to the rms value of the fundamental component
(d) rms value of all the fundamental component to the rms value of all the harmonic components
Answer:

Option (a)

40.
The HF (Harmonic factor of nth harmonic) is the ratio of
(a) an average and a rms value
(b) a rms and an average value
(c) two volt-ampere values
(d) two rms values
Answer:

Option (d)

Showing 31 to 40 out of 100 Questions