1. April 2013
Power Quality, Harmonics and Accuracy

2. Agenda
 What is Power Quality
 Improving Power Quality
 Power Quality in SATEC products
 Accuracy Standards

3. What is Power Quality?
 Definitions of the quality of the supplied voltage (what about the current?)
 Usually referred in negative contexts – power quality problems
 Measurement
– IEC 61000-4-7 Voltage Flicker
– IEC 61000-4-15 Harmonic Measurement
– IEC 61000-4-30 Measurement Accuracy (“Class A”, “Class S”)
– IEC 62052/3-11, 22, 23 Energy Accuracy (“Class 0.2S”, “Class 0.5S”)
 Power Quality
– BS:EN 50160: In use worldwide, in favor of the utilities, voltage only,
statistical standard
– IEEE 519 and IEEE 1159: American standards, practical point of view
– GOST 13019: Russian standard, very comprehensive
– G5/4: British standard for Harmonics (also current)
– Customized: Allows the user to select the best of all, including fault
recording, waveform capture and more

4. Frequency
Voltage Variations
Voltage Flicker
Voltage Dip
Power Quality Parameters

5. Interruptions
Temporary Overvoltage
Transients
Power Quality Parameters

6. Unbalance
Harmonics
Interharmonics
Power Quality Parameters

7. Harmonics
+ =
5
)5sin(
)sin()(
x
xxf 
5
)5sin(
)(
x
xf )sin()( xxf 

8. IEEE1159-EN50160 Levels
IEEE 1159 EN50160
No. Categories Typical Spectral
Content
Typical Duration Typical Voltage
Magnitude
Short Duration Variations
Instantaneous
7 Sag 0.5-30 Cycles 0.1-0.9 pu <1 sec
8 Swell 0.5-30 Cycles 1.1-1.8 pu No
Momentary
9 Interruption 0.5 Cycles-3s <0.1 pu <1 sec
10 Sag 30 Cycles-3s 0.1-0.9 pu No
11 Swell 30 Cycles-3s 1.1-1.4 pu No
Temporary
12 Interruption 3 s-1 min <0.1 pu No
13 Sag 3 s-1 min 0.1-0.9 pu No
14 Swell 3 s-1 min 1.1-1.2 pu No
Long Duration Variations
15 Interruption, Sustained >1 min 0.0 pu Yes
16 Undervoltages >1 min 0.8-0.9 pu Yes 10 min
17 Overvoltages >1 min 1.1-1.2 pu Yes 10 min

9. THD-Total Harmonic Distortion
IN, VN – Individual Harmonics of order N
(%)
.....(
THD(I)
(%)
.....(
THD(V)
I
III
V
VVV
n
n
1
22
3
2
2
1
22
3
2
2
)100
)100





10. ITDD-
I max. demand-
–THD I
IEEETDD
TDD - Total Demand Distortion
(%)
)100
max
22
3
2
2
I
III
demand
n
.....(
TDD(I)



11. K-Factor



n
h
h hIK 1
22
factor

12. Agenda
 What is Power Quality
 Improving Power Quality
 Power Quality in SATEC products
 Accuracy Standards

13. Should we Care about Power Quality?
Comprehensive Research in Europe in 1400 sites at 8 countries reports that
20% experience the following:
 Computer lockouts (20%)
 Light flickering (22%)
 Electronic card failures (18%)
 Power Factor correction system failures (17%)
 Failures in high load switching (16%)
 Neutral conductor overheating (12%)
 Unexpected breaker operation (11%)
 Power meters inaccurate readings (6%)
And of course excess losses and downtime

14. Causes and Solutions
PQ Problem Major Sources Solutions
Frequency The Utility
Voltage variations Load changing
Sync. loads,
Fast PF correction
Voltage flicker
Load changing, mainly
welding
Fast PF correction
Voltage dip
Motor and other load
startups
Motor starters, VFD,
Fast PF correction
Interruptions The Utility
Overvoltage Over PF compensation Fast PF correction
Transients Connections, Switching Controlled switches
Unbalance
Unbalanced loads,
transformer phase shift
Balance the loads
Harmonics Non linear loads, resonance
Active/passive filtration,
detuned capacitors,
Improved VFD operation

15. Agenda
 What is Power Quality
 Improving Power Quality
 Power Quality in SATEC products
 Accuracy Standards

16. RS232/422/485, Profibus, TCP/IP,
Dialup modem, GPRS, RF, USB
Modbus RTU, ASCII, DNP3.0, Modbus/TCP,
DNP3/TCP, Profibus, IEC 61850, IEC 60870
ETC2002
COMMERCIAL & INDUSTRIAL
Multi-Tenant Submetering
Power Measurement
Energy Efficiency & Cost Allocation
Energy Management & Billing
Asset Management
C192PFBFM136 PM172 PM174/5 EM720 EM920 ezPAC
PAS
PM130 PLUS
LAN
ExpertPower™
Server (Pro Edition)
The Full Range of Electricity Management Solutions for Every Application
EM132/3
Substation
Automation
UTILITIES & RENEWABLEALL
Power Quality Analysis
Fault Recording
Revenue Metering
Smart Grid & Demand Response
PM135
Internet
ExpertPower™ Server
(Service Edition)
PM180

17.  Built in analysis to international power quality standards
such as EN50160, IEEE1159, G5/4 and GOST
 Automatic alerts for preventive maintenance
 From simple compliance chart to sophisticated expert
analysis screens

18. EN 50160 Summary Report

19. List of Events
Event
No. Date Time Value Duration
Frequency Variations 67 1809 19/07/2006 17:10.9 48.44 16:3 m
Voltage Dips 122 1986 19/07/2006 14:39.2 69,180 890.0 ms
Long interruption 1 1979 24/12/2006 25:55.9 3,778 5:10 hrs
Transient Overvoltage 133 2263 15/03/2007 55:18.3 180,131 .6 ms
Transient Undervoltage 142 2024 02/01/2007 46:43.8 143,127 .6 ms
THD 3 1998 24/12/2006 12:16.9 0.73 24:43 min
Individual Harmonic H5 9 2271 31/03/2007 28:28.9 2.2 2:16 hrs
Individual Harmonic
H15 2 1984 24/12/2006 13:01.6 0.6 19:60 min
Individual Harmonic
H17 2 1986 24/12/2006 13:01.6 1.14 23:59 min
Individual Harmonic
H19 3 1987 24/12/2006 12:16.9 1.39 24:43 min
Individual Harmonic
H23 3 1992 24/12/2006 12:16.9 1.11 24:43 min
Individual Harmonic
H25 3 1994 24/12/2006 12:16.9 1.17 24:43 min
Individual Harmonic H4 3 1980 24/12/2006 12:16.9 1.97 24:43 min
Total 493
Category
No. of
Events
Worst Case

20. EN50160 Compliance Trends

21. ITI (CBEMA) Curve

22. Deep Analysis of a Dip

23. TDD at 22kV

24. High Individual Harmonics

25. Agenda
 What is Power Quality
 Improving Power Quality
 Power Quality in SATEC products
 Accuracy Standards

26. Full Scale (FS) vs. Reading
 FS Full Scale, error in percents from the maximum
rating
 Example:
Meter with 0.5% FS accuracy connected to 1000A
transformer, the error is 5A. In 500A load the accuracy
is 1% (5/500)
 Reading = Error from the measured value
 In the above example, the 0.5% error will be also in low
load, which means 2.5A only

27. Accuracy vs. Standard
 Various measurement conditions
– Load
– Harmonics
– Power Factor
– Frequency
– and more…
 Various ambient conditions
– Temperature
– EMC (the device and the accuracy)
– Humidity
– and more…
 Tests by independent lab
 Accuracy stability over time
(SATEC is approved for 8 years)

28. Power Factor and Cos 
 DPF = Displacement Power Factor (Cos φ)
 TPF = True Power Factor (incl. harmonics)
Conclusion – practically there is no unity Power Factor.
2
1 iTHD
DPF
TPF



29. Meter Class 0.5 Accuracy
IEC 62053-11

30. CT Class 0.5 Accuracy
IEC 60044-1
Power Factor 0.92 0.50
Error of 45 minutes 0.015% 0.52% 1.14%

31. Power
Meter
CT
Phase
Shift
System
Accuracy
1.58%
System Accuracy
)()()()( 222
zUyUxUzyxU 

32. Meter Class 0.5S Accuracy
IEC 62053-22

33. Power Factor 0.92 0.50
Error of 30 minutes 0.004% 0.34% 0.76%
CT Class 0.5S Accuracy
IEC 60044-1

34. Power
Meter
CT
Phase
Shift
System
Accuracy
1. %
System Accuracy

35. HACS – High Accuracy Current Sensors
 SATEC devices has
numerous amplitude and
phase calibration points

36. Power
Meter
CT -
Included
Phase
shift -
Included
System
Accuracy
%
System Accuracy

37. Comparison
Class 0.5 Class 0.5S
Class 0.5S
with HACSes
(or direct connection)
Power Meter Accuracy 0.8 0.6 0.6
CT Accuracy 0.75 0.5 Included
Phase Shift 1.14 0.76 Included
System Accuracy 1.58 1.09 0.6

38. Accuracy is for Engineers,
Money is for Decision Makers
 1000 kVA transformer
 80% load
 0.90 Power Factor
 0.15 US$/kWh
 The difference between
0.6% to 1.58% equals to
US$ 9,272 each year

39. Accuracy Standard Pyramid
Class A
Class S
Class 0.2S
Class 0.5S
Class 0.5
Class 1
Class 2
%Readings
%FS (Full Scale)
No stated accuracy
---IEC-
Min. Acceptable
Not included:
Class B – meaningless
Class 0.1, 0.2 – only for CTs

40. SATEC
Empowering the Smart Grid
www.satec-global.com