Lecture 11 Power factor correction Power factor What

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Lecture 11 Power factor correction

Lecture 11 Power factor correction

Power factor :

Power factor :

綜合功率因數計算: What is the total power factor ?

綜合功率因數計算: What is the total power factor ?

如何計算電容量: Active power Reactive power Apparent power

如何計算電容量: Active power Reactive power Apparent power

example A 3/4 HP electric motor has a power factor of. 85. The nameplate

example A 3/4 HP electric motor has a power factor of. 85. The nameplate current is 10 Amps at 115 Volts, or 1150 Volt Amps. Apparent power = 1150 Volt Amps Active power =. 85 * 1150 = 977. 5 Watts Reactive Power = sqrt(1150^2 - 977. 5^2) = 605 VAR So, we need 605 var of power factor correction. Calculating the required impedance from Q = E^2/X 605 = 115^2/X => X = 115^2/605 = 21 ohms C = 1 /( 2 * pi * f *X) = 1/ (377 * 21) = 126 u. F