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All rights reserved. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying or recording, or by any information storage and retrieval system, without permission in writing from publisher.

BELUK GmbH

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••••Taubenstr. 1 •••• Phone +49 8861 2332-0 •••• Fax +49 8861 2332-51

ϕ

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1. How Electrical Reactive Power Originates

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ϕ

ϕ

[ ]

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2. Recording the Resultant Electric Reactive Power

ϕ

ϕ

ϕ → ϕ

ϕ

ϕ

ϕ ≠

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3. Calculation of Capacitor Bank Size

ϕ

72.08200

var5900tan ==kWh

hkϕ

ϕ → ϕ

ϕ

ϕ

ϕ

ϕ → ⋅ ϕ

ϕ → ϕ → ϕ

⋅

ϕ

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ϕ → ϕ → ϕ

⋅ ϕ ⋅

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4. Selection of Switching Programme and Relay Types

4.1 Response Value (C/k-Value)

= ⋅⋅ ⋅

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4.2 Economy or “Step-back” Switching Programmes

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4.3 Rotational Switching Programme

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5. Function of the Electronic Power Factor Control Relays of C-Series

5.1 Structure and Mode of Operation

5.2 Operating and Signalling Elements on BLR-CA

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5.3 No-Volt Release Feature

5.4 Target Power Factor Setting and Starting Current

5.5 Hand / Automatic Switching

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5.6 Technical Data on BLR-CA (C-series)

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5.7 Connection Diagram of BELUK Power Factor Control Relays

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5.8 Determining the Required Current Transformer

⋅

= ⋅ ρ

ρ Ω

Ω

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•

2 8m 0.0178 mm2,5mm m

0.1142

2

• • =Ω Ω

• Ω

•V

A

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6. Explanatory Notes on the Compensation Procedure in General

ϕ

ϕ

ϕ

ϕ ϕ

ϕ

ϕ

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6.1 Relationship between Response Value (C/k-Value) and cos-ϕϕϕϕ setting

ϕ

ϕϕ

ϕ ϕ

ϕϕϕϕ

ϕϕϕϕ

ϕ

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ϕϕ

ϕ

ϕ

ϕ

ϕ

ϕ

ϕ

ϕ

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6.2 Power Factor Control Relays with Automatic C/k-Adjustment (C-series)

ϕ

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ϕ

1 Transformer switch-over 5A / 1A (except BLR-CC)

2 Alarm ON/OFF 3 Function Switch 4/5 +/- Button 6 Stage indicator 7 TTL-Interface

(except BLR-CC and CD)

8 Display/ Cos ϕ Indication

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7. Reactive Power Compensation in the Four Load Quadrants

7.1.1 Technical Consideration

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ϕϕ ϕ

ϕ

ϕ

ϕϕ

ϕϕ

ϕ

ϕ

ϕ

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Variation of Power Factor on Import and Export of Power

Case a): All power imported

Case b) Power partly supplied by Generator(s)

Case c) All Power supplied by Generator(s) and Power Export

Measuring point: Current Transformer at Main Incomer or at Metering Point

PN S

Q

PN

PV

cosϕ = 0,23S

Q

PG

cosϕ = 0,24S

Q

PG

cos ϕ = 0,73

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7.1.2 Commercial Consideration

ϕ

ϕ

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7.2 Reactive Power Compensation with “Mixed Measurement”

BLRCA-12

20 kV / 50 Hz

50 A / 5 A; k = 10 (Phase L2)

Transformator1250 kVA20 kV / 0,66 kVDd 6

660 V / 50 Hz

Kompensation12 x 60 kvar

660 V / 400 V(Phasen L3/L1)

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Current transformer in L1 Measuring voltage

(H.V.-side) (L.V.-side)

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7.2.1 Calculation of C/k-Value in case if “Mixed Measurement”

ArkV

kkC 10.010320

var606.0/ ≈⋅⋅

⋅=

⋅ ⋅

⋅ ⋅ ≈-

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8. Reactive Power Compensation with more than one Incoming Supply

8.1 Central Compensation by means of Summation Measurement

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1200A 1200A 1200A5A 5A 5A

5A 5A 5A5A

3600A15A

15A5A

240 3 720+ ++ +

• + + = • = • =

0.6 PU 3 k

0.6 33.3 kvar0.4 kV 3 720

0,04Arc•• •

=•

• •=

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0.600.04Ar

x0.05Ar

0,06 0.05Ar0.04Ar

= = •

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8.2 Individual Compensation of Each Incoming Supply

k 1200A5A

240= =

Ar0.182403kV0.4

kvar500,6=

•••

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9. How to Trace Possible Mistakes when connecting Power Factor Control Relays of the Series C

ϕ

= ⋅⋅ ⋅

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= ⋅⋅ ⋅

=

ϕ

ϕ

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10. Indirect Capacitor Control (z) on BELUK Power Factor Control Relays, Type CA

The true Purpose of Harmonic Analysis

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