Power Quality And Management Set 4 MCQs

Q1 | In a load comprising of resistance and inductance:

Load current lags voltage

Load voltage lags current

Both are in phase

Any of above

Q2 | The power factor of capacitive circuits is:

Leading

Lagging

Both of these

Any of these

Q3 | A circuit having poor power factor will draw:

No current

Low current

Normal current

High current

Q4 | The power factor of purely inductive circuits is:

Leading

Lagging

Both of these

Any of these

Q5 | A 500 kVA circuit drawing 200 kW and an inductive load requires how much capacitance to obtain unity power factor:

100

200

300

400

Q6 | Which of the following statement refer to IEEE definition on power quality?

The concept of powering of any electronic equipment in a manner suitable for the equipment.

The concept grounding sensitive electronic equipment in a manner suitable for the equipment.

The concept of grounding for whatever equipment in a manner suitable for the equipment.

The concept of powering and grounding sensitive electronic equipment in a manner suitable for the equipment.

Q7 | Which of the following explains the reasons for concern with power quality?

End-user equipment become more sensitive to power quality due to many microprocessor-based controls

The adjustable-speed motor drives helps to reduce harmonic levels

Modern load & equipment are less sensitive to power quality variations.

Power electronics equipment do not affect the power quality at all.

Q8 | The following statement describes the effects of poor power quality, EXCEPT

Equipment malfunction

Increased costs from downtime

Premature failure of equipment

Reduced maintenance, repair time and expenses

Q9 | Since most of the industrial loads are inductive type, which of the following will help to correct the power factor?

Increase lagging reactive current demand of the loads

Compensate lagging reactive current by supplying leading reactive current to the power system

Compensate leading reactive current by supplying lagging reactive current to the power system

Reduce leading reactive current demand of the loads

Q10 | Which of the following is an advantages of power factor correction (PFC)?

Electricity bills increased

Power consumption reduced

Increased heating in equipment

Extra kVAr availability from the supply

Q11 | Which of the following represents short duration voltage variation?

Under Voltage

Over Voltage

Voltage Outage

Voltage Interference

Q12 | Which of the following terms describes the transient voltage variation?

The duration is within 0.5 s to 30 cycles

It can be classify to instantaneous, momentary or temporary

It can be solved by using static Var systems

It can be caused by lightning, electrostatic discharge or load switching.

Q13 | Which of the following terms describes the effects of harmonics to industrial power systems?

Disturbance to Electric and Electronic Devices

Extra Fault Current

Lower Losses

Increased costs from downtime