Page 7 - ELECTRONICON_Katalog_PFC-60Hz
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INTRODUCTION
A. Calculation based on the consumption data
- consumption of active energy: E = 300.000 kWh Example
W
- consumption of reactive energy: E = 400.000 kvarh
B
- number of working hours: t = 600 h
300.000 kWh
E W
1) Calculation of average active power P P= = = 500 kW
t 600 h
1 1
2) Calculation of initial power factor cosφ 1 cosφ = = = 0.6
1
E B 2 + 1 400,000 kvar 2 + 1
E W 300,000 kWh
3) From chart 1, we read the factor 1.13 for the improvement of the power factor from 0.6 to 0.98.
4) Calculation of required capacitor power Q = 500 kW · 1.13 = 565 kvar
C
B. Calculation based on the Energy Bill
- reactive power tariff: T/kvarh
- monthly costs for reactive energy: C
- number of working hours: h
C
Calculation of required capacitor power for cosφ = 1 Q c =
h · T
kvarh
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