The document discusses power factor correction for mining applications using metal enclosed capacitor banks. It provides an example of how improving power factor from 0.5 to 0.98 can reduce the required system capacity by 33%. The document then describes ABB's low and medium voltage metal enclosed capacitor banks, which provide automatic power factor correction to maintain a target power factor. It highlights safety and arc containment features. Finally, it presents a case study of a gold mine where installing a 3-stage 3000 kVAR metal enclosed capacitor bank improved the power factor from 0.73 to 0.9, reducing the maximum demand by 1680 kVA.

1. address
Rob Symonds, Power Products Division, Oct 2013
Metal Enclosed Capacitor Banks for
Mining Power Quality Applications
© ABB Group
November 4, 2013 | Slide 1

2. Why Improve Power Factor?
Power Factor Considerations
The lower the power factor, the more reactive power the
Utilities need to provide. This can result in:


System capacity problems due to inefficient loading of
incoming transformers

© ABB Group
Larger equipment (i.e. poles and wires) required to supply
power
Higher operating costs due to maximum demand charges –
kvar (kVA) tariff, local generation costs and energy loss

3. Example
kW
kVA
kvar1
A consumer using 500kW at 0.5 power factor compared
with a similar 500kW consumer at 0.98 power factor would
require 33% more system capacity to meet requirements
© ABB Group
November 4, 2013 | Slide 3

4. Power Factor Improvement
1000kW
Power Factor
= 0.9
1428kVA
1250kVA
1111kVA
1009kvar
750kvar
482kvar
1500kVA Transformer
Recovered Capacity
= 317kVA (22.19%)
© ABB Group
November 4, 2013 | Slide 4

5. ABBACUS
Low Voltage Power Factor Correction

LV ABBACUS

Rated to 415V

Indoor and Outdoor

Standard Step Sizes


Automatic Operation


© ABB Group
November 4, 2013 | Slide 5
12.5kvar, 25kvar,
50kvar
RVC & RVT controllers
Harmonic Protection

6. ABBACUS
MV Metal Enclosed Capacitor Bank


Inrush and detuned reactors, up to 36kV

© ABB Group
November 4, 2013 | Slide 6
Range of outdoor & indoor aluminium designs to IP55
Switched and fixed options

7. Metal Enclosed Capacitor Bank Concept
Maintaining a target PF by switching capacitor stages
automatically based on load profile

Typical mining operations have a load profile which
varies according to


Day of the week


Time of day
Time of the year
Metal Enclosed APFC banks are energised on
demand

© ABB Group
November 4, 2013 | Slide 7
No under or overcompensation

8. Metal Enclosed Capacitor Bank
Benefits to the Mining Industry

One Stop Shop


Compact Footprint

© ABB Group
November 4, 2013 | Slide 8
System Integration of
primary and secondary
components
Metal Enclosed APFC
occupies 60% of the
floor space of and
equivalent open bank

9. Metal Enclosed Capacitor Bank
Benefits to the Mining Industry
Incomer module
Power module(s):
Detuned design
Control and protection
Inrush design
© ABB Group
November 4, 2013 | Slide 9

10. Metal Enclosed Capacitor Bank
Safety Features
Operator Safety

Live parts enclosed

Interlocking system

Bank de-energised

Capacitors discharged


© ABB Group
November 4, 2013 | Slide 10
Q-ACT Arc fault
Containment Technology
Ceiling over pressure vents

11. Metal Enclosed Capacitor Bank
Q-ACT Arc Containment Technology
Key Benefits


Solution is type tested to IEC 62271-200 : 2003 Clause 6.106

Increase system and process availability

Minimise repair costs after a fault event has occurred

© ABB Group
November 4, 2013 | Slide 11
Increase public and operator safety
Limit system down time

12. Metal Enclosed Capacitor Bank
Case Study
Introduction

Australian gold mine



Minimise power charges
Comply with regulation
Load


DOL motors, variable
speed drives
Load Details


PF 0.73

© ABB Group
November 4, 2013 | Slide 12
11kV
MD 8492kVA

13. Metal Enclosed Capacitor Bank
Case Study Continued…
Analysis

Target PF 0.9

Bank Design


3 Stages

Step size 1000kvar

Sequence 1:1:1

© ABB Group
November 4, 2013 | Slide 13
3000kvar
Detuned

14. Metal Enclosed Capacitor Bank
Case Study Continued…

Protection


© ABB Group
November 4, 2013 | Slide 14
Unbalance
Over current / earth fault

15. Metal Enclosed Capacitor Bank
Case Study Continued…
Metal Enclosed Capacitor
Bank Specifications
Result : reduced 1680 KVA
© ABB Group
November 4, 2013 | Slide 15
Transformer – Generators $$

16. Metal Enclosed Capacitor Bank
Case Study Conclusion
Whether a cable car or a coal mine…the implementation of
reactive compensation can reduce


Transformer and cable sizing, and carbon emission reduction

Fuel saving when generating locally

© ABB Group
November 4, 2013 | Slide 16
kVA demand charges from Utility (kW PF penalties)
Generally a conservative 2-3 year payback

17. Metal Enclosed Capacitor Bank
Case Study Conclusion
Metal Enclosed Capacitor Bank (MECB)

Proven design

Factory tested

Fully Integrated

Modular

Arc Containment Technology (Q-ACT)

Applications

Mining, Water Pumping , Petro Chemical, Airports


© ABB Group
November 4, 2013 | Slide 17
Flexible concept suiting wide range of applications
Cost effective answer to reactive compensation needs
in industry