What is the effect of Leading Power Factor on Electrical System

 Leading power factor means that the current leads the voltage.  In other words, the load is capacitive.

 If the real power load is 10kW at unity power factor, the kVA is 10kVA.

 If the real load power is 10kW at 0.95 power factor (Leading Or Lagging), kVA is 10.52kVA.

The effect of leading power factor on the network are as follows

1) More current would flow in the circuit, this current could go above the cable ratings and higher current means bigger cables.

S = VA

Where:

S = 10.52kVA = 10520VA

V = 415

A =?

10520 = 415 x A

A = S/V = 25.35A in the circuit instead of 24.1A at unity PF


2)  Leading power factor will boost the output voltage of the supply generator. This happens due to over excitation of generators. (Leading PF causes high voltage in the circuit) 

When Electrical devices equipment's are supplied with a voltage higher that its rated voltage, equipment damage/failure would most certainly occur. 


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