Electricity
Quantity & Quality
Hervé Mougeot
1
Market Overview
Quantity Quality Safety
• Quantity : Allocate energy usage, detailed
cost analysis, cut energy costs, negotiate
better energy contracts, demand control and
peak saving, information for improving
infrastructure, load curtailment and price
response, power factor correction.
• Quality : Availability, troubleshooting,
productivity, preventive maintenance,
quality statistics, information for improving
infrastructure
Quality
U
=
Z
Safety
I
Quantity
• Safety : protect people and property
2
Electrical Network
Production
Transmission
Distribution
Users
LV
HV
MV
Network = Share of the electricity ... and the pollution.
Example : The pollution generated from a disturbing load will be distributed to the
neighbors more or less attenuated depending on the network impedance.
3
Disturbance level
ElectroMagnetic Compatibility
Immunity secured load
Immunity standard load
Compatibility
EN50160
Emission on the network
Emission from single load
IEC1000-3-x
t
4
ElectroMagnetic Compatibility
5
Compatibility
Transient
Swell
Dip
6
3 Phases System
U31
V3
U23
V1
V2
U12
U =V 3
7
Electrical Disturbances
low frequency, conducted
• Amplitude
• Wave Shape
• Frequency
• Symmetry
• Voltage variations
• Voltage Dips
• Interruptions
• Voltage Swells
• Flicker
• Harmonics
• Inter harmonics
• Transients
• Frequency
• Unbalance
8
Voltage Variations
9
Voltage Dips
Ueff
%Un
u
100
ΔU = 30%
(depth)
90
70
t
ΔT = 112ms
(durée)
U
(amplitude)
t (ms)
0
40
80
120
160
200
240
280
0
40
80
120
160
200
240
280
10
Interruptions
Ueff
%Un
u
100
ΔT = 83ms
t
(duration)
1
t (ms)
0
40
80
120
160
200
240
280
0
40
80
120
160
200
240
280
11
Dips, Swells and Interruptions
12
Flicker
8,8Hz
13
Flicker
10
V
V
3% / 0,757
1
0,29% / 1052
Nombre de variations par minute
0,1
1
10
100
1000
Pst = 1 , cas des variations rectangulaires
14
Harmonics
=
+
+
=
1
3
5
n
15
Harmonics
16
Transients
17
Unbalance
U1
vIE
IE
2vIE
IE
ZA
vIE
U2
U3
G
SA
TU U
=
UM
SK
=
(1-Phase-Load)
18
Frequency Variation
19
Disturbances
Dips, Swell,
Interruptions
Harmonics
Flicker
Transients
Unbalance
Frequency
Variation
20
Parameters
Parameters
Value
Limits
Urms LV
230V / 400V
+10% / -10%
Urms MV
20kV
+7% / -7%
Frequency
50 Hz
+2% / -2%
Wave shape
Sinusoidal
THD < 8% en BTA
Symmetry U
U1=U2=U3
2%
21
What to measure
EN 50160
Voltage characteristics in public distribution systems
22
EN 50160 Parameters








Voltage Variations
Flicker Pst/Plt
Harmonics order 2 to 25, THD (40)
Signalling (ripple control) voltages
Frequency
Unbalance
Voltage dips and swells
Interruptions
Measurement over 1 week
23
EN 50 160 - Limits
Parameter
Averaging
time
Limits for 95% of 1 week limits for 1 week
Voltage variations
10 min
 10%
Flicker
Pst 10 min
-15% - +10%
Plt 120 min
Plt < 1
Harmonics
10 min
table up to 25th harmonic
THD
10 min
< 8%
Signaling voltages
3 sec
< 5%of UN
(1...10kHz) 99% of 1
day
Frequency
10 sec
 1%
Unbalance
10 min
< 2%
Voltage dips
Urms 1/2
not defined
Interruptions
Urms 1/2
not defined
+4% / -6%
24
EN 50 160 - Data
Parameter
Averaging
Number of parameters
Data over 1 week
3
3024
Plt 120 min
3
3024
Harmonics
10 min
75
75600
THD
10 min
3
3024
Signaling voltages
3 sec
Frequency
10 sec
1
60480
Unbalance
10 min
1
1008
Voltage dips
Urms 1/2
not defined
Interruptions
Urms 1/2
not defined
time
Voltage variations
10 min
Flicker
Pst 10 min
25
To measure according EN 50 160
=
150.000 data to analyze
for 1 week, for 1 point !
To analyze according EN 50 160
=
1 second with DRANETZ BMI
27
90 curves to analyze
amplitude
4
9
7
2
1
3
5
8
10
6
time
Compression of the information
amplitude
4
3
1
6
2
5
8
9
7
10
number of measuring values
amplitude
4
9
7
2
3
5
1
8
10
6
time
amplitude
4
3
1
6
2
5
8
9
7
10
number of measuring values
amplitude
4
3
1
6
2
5
8
9
7
10
number of measuring values
Amplitude
standard
number of measuring values
95 %
100%
Amplitude
standard
number of measuring values
95 %
100%
Amplitude
standard
number of measuring values
95 %
100%
Amplitude
standard
number of measuring values
95 %
100%
Overview about the Power Quality
How to measure
IEC 61000-4-30
Testing and measurement techniques – Power Quality measurement methods
36
Measurement techniques
Continuity / Change
Permanent / Trigger
Permanent average values
recording
–
Triggered values recording
Events / Trend
FFT
X²
8
A/D
256 s/c
16-Bit
T
(4)
A/D
FIFO
T
1 MHz 12-Bit
Transient
X
39
Measurement methods
40
Event recording
Acquisition
Treatment
Characterization
Measure
Detection
Evaluation
Classification
Analyze
Archive
Recording
41
Voltage Dip / Swell (5.4)
Voltage Interruption (5.5)
• Derived from ½ cycles
(3.22 1cycle refreshed each 1/2cycle, 20msec)
• Reference is either Udin (LV) or
sliding voltage (MV, HV)
• ½ cycles must be synchronised on reference channel
42
Long term recording
Time aggregation
•10/12 cycle (200msec) at 50/60Hz, 150/180 cycles (3sec) at
50/60Hz, interval time varies with actual frequency
• 10min, 2h interval sync to clock (including defined algorithm from
cycle to time aggr.)
• Aggregations are performed using the square root of arithmetic
mean of squared input
• All are non-gapping, 150/180 aggregated out of 15x10/12; 2h out
of 12x10min
43
Time aggregation (4.4/4.5)
• 10/12 cycle (200msec) at 50/60Hz, interval time varies
with actual frequency
• 150/180 cycles (3sec) at 50/60Hz, interval time varies
with actual frequency
• 10min interval sync to clock (including defined
algorithm from cycle to time aggr.)
• 2h interval sync to clock (including defined algorithm
from cycle to time aggr.)
• Aggregations are performed using the square root of
arithmetic mean of squared input
• All are non-gapping, 150/180 aggregated out of
15x10/12; 2h out of 12x10min
44
Time aggregation (4.4/4.5)
Zero Crossing of Fundamental (filtered)
10
150
Synchronised Clock ±20msec
10min
2h
45
Time Clock Uncertainty (4.6)
• For Timestamp of Events and
• Synchronisation of the 10min and 2h interval
• Accuracy of timestamp: ±20/16,7msec at 50/60Hz
(Realisation with e.g.: GPS or DCF 77 sync)
46
Flagging (4.7)
• Only one event extracted out of different events
(dip, swell and interruption influences also frequency,
flicker…)
47
Power Frequency (5.1)
• Obtained every 10sec from the reference channel
• Synchronise the sampling frequency of the system
no fix sampling frequency 'possible' (e.g.: PLL)
• Accuracy of power frequency measurement ±0,01Hz
48
Accuracy for voltage (5.2)
• Accuracy without accessory: ± 0,1% of Udin
(Udin declared input voltage)
• (same for current, but today only recommended)
49
Flicker (5.3)
Flicker algorithm according to IEC 61000-4-15
50
Supply Voltage Unbalance (5.7)
• out of 10/12 cycle
positive and either negative or zero sequence
51
Voltage Harmonics (5.8)
Voltage Interharmonics (5.9)
• Harmonics according new IEC 61000-4-7 Subgroups!
(2002 class1, out of 10/12cyclel with 10 bins)
• Interharmonics acc. new IEC 61000-4-7 Subgroups!
(2002 class1, out of 10/12cycles)
• Gapless (every 10/12 cycles a new set of data)
• Accuracy Class I of IEC61000-4-7
(bandwidth with accuracy 2,5/3kHz 50th harmonic
low ripple)
52
Voltage Harmonics (5.8)
Voltage Interharmonics (5.9)
harmonic
subgroup n+1
interharmonic
subgroup n+2,5
YES 
DFT output
harmonic
n
order
n+1
harmonic
group n+1
S
n+2
n+3
interharmonic
group n+2,5
NO 
harmonic
n
order
n+1
n+2
n+3
DFT output
53
5.10 Mains Signalling Voltage
• either derived from 10/12 cycle or
• interharmonic bin all below 3kHz
54
Where to measure
Compliance / Trouble shouting
55
Transient
User
Network
Swells
Flicker
Dips
Instantaneous
Momentary Temporary Long Duration
Interruptions
Duration
56
Measuring point
Statistics
/
Diagnostic
57
Multi-sites monitoring
58
Multi-sites monitoring
A lot of data :
• To transmit
• To analyze
59
Analysis
60
Embedded analysis
61
How to analyze
Overview / Details
62
Overview
63
Overview
64
Trends
Di ag ram m e tem p ore l
250
200
Volts
150
100
50
0
A Vrms
DEMO
20
15
10
5
0
A VPlt
26/01/2006
Thursday
28/01/2006
Saturday
30/01/2006
Monday
01/02/2006
Wednesday
03/02/2006
Friday
05/02/2006
Sunday
Evénément #109 l e 24/01/2006 18:27:16,080
AVrms C reux i nstantané
65
Trends
66
Overview
67
Events
68
Classification
69
Details
70
Key points
• To measure ALL the parameters at the
same time through differential inputs
• To measure according IEC 61000-4-30
class A
• Adapted trigger mode
• Easy to configure
• Automatic overview
71
Complete solution
72
Solution : DRANETZ BMI
Power Network Monitoring
Power Quality
Compliance
Power Quality
Analysis
Sporadic
Disturbance
Permanent
Disturbance
Voltages Only
Voltages + Currents
Long Term Monitoring
Short Term Monitoring
Key Account
Strategic Point
FIXED MONITORING
Digital
Signals
RMS
Only
ENCORE SERIES
MOBILE INSTRUMENTS
Waveform
+ RMS
Transient
Power Xplorer
PX5
Waveform
+ RMS
Power Guide
4400
Power Visa
73
Selection
Power Network Monitoring
IEC 61000-4-30
Class A
Sporadic
Disturbance
Good Quality ?
Preventive
Maintenance
Voltages RMS
(only)
Voltages +
Currents
RMS
Power Quality
Compliance
Exchange
Point
Permanent
Disturbance
Predictive
Maintenance
Power Quality
Analysis
Voltages + Currents
Waveform
Trouble Shooting
Strategic
Point
Trend recording
Multi-points
Statistics
Low Speed Events
recording
High Speed Events
recording
EN50160
Diagnostic
Power Guide 4400
DranView
Short Term Monitoring
Long Term Monitoring
Mobile
Instrument
Power Visa
Power Xplorer PX5
Reporting
Fixed
Installed
Solution
ENCORE SERIES
Permanent Monitoring
Digital Signals
Analysis / Statistics
RMS
Waveform
Alarms
Transient
74
Questions?
Electricity - Quantity & Quality
75