Engineering Board Exam Reviewer · RLC Circuits and Resonance · medium
A 10 kW single-phase load operates at 0.8 power factor lagging. How many kvar of capacitance must be connected in parallel to raise the power factor to unity?
- 8 kvar
- 12.5 kvar
- 7.5 kvar
- 6 kvar
Answer
C. 7.5 kvar
Solution
= -10.8=36.87°. The load's reactive power is Q=P =10,000 36.87°=7500 var. The capacitor must supply this, so QC=7.5 kvar.
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