Calculating Average Power Factor?

In regard to each rated power ,you shall do vector or phasor calculation.

REGARDS

MSJ

In a three phase sinusoidal power distribution service, with phases A, B and C, we can write:

P = Ea Ia COS(a)+ Eb Ib COS(b)+ Ec Ic COS(c)

Q = Ea Ia SIN(a)+ Eb Ib SIN(b)+ Ec Ic SIN(c)

S=√ (P2+Q2)

Power factor generally is defined by :

Fp= (total active power)/(phasor power)=P/S often ≠ COS(Ө)

Therefore in unbalance phasor system, power factor can not be defined as the cosine of the phase angle.

REGARDS

MSJ

1. Calculate the KVA of each feeder:
• KVA₁ = KW₁/pf₁
• KVA₂ = KW₂/pf₂
• KVA₃ = KW₃/pf₃
2. Sum all feeder KVA to get System KVA:
• KVA_System = KVA₁+KVA₂+KVA₃
3. Sum all feeder KW to get System KW:
• KW_System = KW₁+KW₂+KW₃
4. Calculate System pf.
• pf_System = KW_System/KVA_System