Schneider Electric - Electrical installation guide 2009
L
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Chapter L
Power factor correction and
harmonic filtering
Contents
Reactive energy and power factor
L2
1.1 The nature of reactive energy
L2
1.2 Equipment and appliances requiring reactive energy
L2
1.3 The power factor
L3
1.4 Practical values of power factor
L4
Why to improve the power factor?
L5
2.1 Reduction in the cost of electricity
L5
2.2 Technical/economic optimization
L5
How to improve the power factor?
L7
3.1 Theoretical principles
L7
3.2 By using what equipment?
L7
3.3 The choice between a fixed or automatically-regulated bank
L9
of capacitors
Where to install power factor correction capacitors?
L0
4.1 Global compensation
L10
4.2 Compensation by sector
L10
4.3 Individual compensation
L11
How to decide the optimum level of compensation?
L2
5.1 General method
L12
5.2 Simplified method
L12
5.3 Method based on the avoidance of tariff penalties
L14
5.4 Method based on reduction of declared maximum apparent
power (kVA)
L14
Compensation at the terminals of a transformer
L5
6.1 Compensation to increase the available active power output
L15
6.2 Compensation of reactive energy absorbed by the transformer
L16
Power factor correction of induction motors
L8
7.1 Connection of a capacitor bank and protection settings
L18
7.2 How self-excitation of an induction motor can be avoided
L19
Example of an installation before and
L20
after power-factor correction
The effects of harmonics
L2
9.1 Problems arising from power-system harmonics
L21
9.2 Possible solutions
L21
9.3 Choosing the optimum solution
L23
Implementation of capacitor banks
L24
10.1 Capacitor elements
L24
10.2 Choice of protection, control devices and connecting cables
L25
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Schneider Electric - Electrical installation guide 2009
L - Power factor correction and
harmonic fi