Power Quality StudyThe Project ACROPOLIS A R PROPERTY SERVICES,
148, R.K. SALAI Mylapore, CHENNAI - 600 004
Study conducted by Interface Electronics Pvt Ltd 13,Nana Street,
T. Nagar,Chennai, India, 600017 Email:[email protected]
Website:www.ifepwrana.com Tf No: 9884370326
Power Quality Study for ACROPOLIS, A R Property Services, 148, R
K Salai, Mylapore, Chennai.
Report on Power Quality study at ACROPOLIS, Chennai1.
IntroductionThe Client M/S. A R PROPERTY SERVICES CHENNAI, have
requested M/S. Interface Electronics Pvt Ltd, Chennai to conduct a
harmonic study at their software buildings located in Chennai in
order to derive a better understanding of the harmonic distortions
and the level of neutral currents at those buildings and to arrive
at recommendations on remedial measures if needed. Recently there
was a circular from TNEB, which states that all HT I and HT III
consumers should provide harmonic suppression equipment such that
they do not produce harmonics more than the specified limits in CEA
regulation, as per TNERC order no 1 of 2012 dated 30/03/2012. The
relevant extract from the TNERC order no 1 of 2012 dated 30/03/2012
is reproduced below Quote
Unquote
Standards for Connectivity to the Grid) Regulations, 2007 is
also reproduced hereStudy Conducted by Interface Electronics Pvt
Ltd, Chennai
Page
The relevant extract regarding Harmonics from The Central
Electricity Authority (Technical
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
K Salai, Mylapore, Chennai.
Quote
Unquote From the above circulars it is to be understood that the
Harmonics generated by the consumer to be measured at the point of
coupling (PCC) and action to be taken to suppress the same if it is
found to be beyond the limits. Therefore this study is made.
The Single line diagram of the Electrical distribution system
for the premises is shown in annexure. The studies were made during
16/6/2012 and 17/06/2012
2. Electrical Distribution SystemFor ACROPOLIS, 11kV Power is
received from TNEB from a ring main unit. The 11kV power is stepped
down to 433Volts through a 1600 kVA Distribution Transformer and
distributed to various loads through main PCC and Rising mains.
There are three numbers 1010 kVA DG sets operating in parallel
supply power to Main PCC in case of Emergency and Mains Power
Failure. The Distribution Transformer is rated 1600 kVA, Dry Type,
11/0.433 kV with Z=6.25% Power quality monitoring instruments were
connected in the circuits as marked PCC1.PCC6 in the SLD Block
diagram annexed. The recordings of the instrument readings are
given in the excel sheet, details are given below.
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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2. Study details:Krykard Instrument type C A 8335 sl no: -212902
5:8.2.6 was used to collect data. Power Analyzer Transfer software
tool used for studying the data collected by the above instrument
The details of study made are given in the Table 1 .This table
gives where and when the instrument connected in the circuit for
data collection. The Table also gives name of the excel file in
which data are stored. a) The data was collected on the 11 kV
incoming supply side to ascertain the presence of Harmonics. This
is Point of common coupling (PCC). The standard defines it as the
electrical connecting
point or interface between the utility distribution system and
the customer's or user's electrical distribution system. b) The
data also collected by connecting the instrument on the secondary
side of the transformer at different times to record parameters
with different loads like Load with Capacitors connected, Load
without Chiller connected and all loads without Capacitors. c) The
data also collected by connecting the instrument at the load
feeders viz RRD 80 kVA UPS Feeder RRD 250 kVA Feeder Chiller Feeder
Thompson UPS 1 Feeder Thompson UPS 2 Feeder Thompson Server 1
Feeder Thompson Server 2 Feeder to ascertain the level of Harmonics
generated by individual loads .
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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d) In the table 2, the details of average and maximum Total
Harmonic Distortion of Phase voltage, Line voltage Line currents
are tabulated. e) The Current measured, total current distortion
and individual odd current harmonics from 3 to 25 are recorded in
the table 3 .Also based on Isc / IL, permissible %THD limits are
indicated for each measurement. The permissible harmonic limits
depend on the location of PCC. f) In table 4, voltages measured,
total voltage distortion, odd voltage harmonics from 3 to 25 are
tabulated.permisible harmonic limits also indicated in the table.
g) The Table 5 gives the details of maximum Current harmonic
content permitted as per IEEE 519-1992. h) Trend curves of Current
THD,Voltage THD,Unbalance of Voltage, Unbalance of
current,Powerfactor,Line voltage and Line current for measurement
done at HT Incomer (PCC1)are given in following pages, Also Current
and Voltage Harmonic Spectrum upto 25 th harmonic is added in the
pages. 3. Observations:a) At PCC1 the Current and voltage harmonics
are within the stipulated limits as per IEEE512-1992 b) However at
PCC2 voltage harmonics are within limits, but current harmonics are
slightly above the stipulated limits as per IEEE512-1992. c) On
analysis it is observed that the harmonics generated by RRD 80 kVA
UPS Feeder , Thompson UPS1Feeder and Thompson UPS2 Feeder is very
high. d) There is no impact of harmonics due to Chiller load as it
generates Current harmonics only 2-3%
4. Recommendations and Conclusion:a) TNEB metering is located in
the 11 kV incoming supply and the TNEB will check the harmonics at
this point (PCC1).At PCC1 ,the Current and Voltage harmonics are
within the stipulated limits as per IEEE5121992 and no mitigation
of harmonics is required to satisfy TNEB b) However suitable
Harmonic Active Filters for the feeders RRD 80 kVA UPS Feeder ,
Thompson UPS1Feeder and Thompson UPS2 Feeder are recommended to be
installed as the harmonics generated by these feeders are high to
pollute the system.
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
K Salai, Mylapore, Chennai.
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
K Salai, Mylapore, Chennai.
Details of StudySl.No Description1 Main Incomer 11 kV 3 Main
Incomer LT with Full Load 1 Main Incomer LT side with APFC 4 Main
Incomer LT without Chiller Load 5 Chiller 1 6 RRD 80 kVA UPS Feeder
7 RRD 250 kVA UPS Feeder 8 Thompson UPS 1 Feeder 9 Thompson UPS 2
Feeder 10 Thompson Server 1 Feeder 11 Thompson Server 2 Feeder
17-06-2012 16-06-2012 16-06-2012 16-06-2012 16-06-2012
16-06-2012 16-06-2012 16-06-2012 16-06-2012 16-06-2012
16-06-2012
Start :Date (dd-mmyyyy)
12:27:00 PM
Start:Time Finish: Date Finish:Time (hh:mm:ss) (dd-mm(hh:mm:ss)
yyyy)17-06-2012 16-06-2012 17-06-2012 16-06-2012 16-06-2012
16-06-2012 16-06-2012 16-06-2012 16-06-2012 16-06-2012 16-06-2012
4:29:56 PM 12:47:00PM 9:14:12 AM 01:00:00PM 04:24:00PM 03:53:00PM
03:36:00PM 01:40:00PM 02:00:00PM 03:00:00PM 03:10:00PM
04:02:56 01:00:00 10:59:12 00:10:00 00:09:58 00:05:00 00:10:00
00:15:00 00:10:00 00:09:00 00:05:00
Duration Measur EXCEL (hh:mm:ss) ing file Point namePCC1 PCC2
PCC2 PCC2 PCC3 PCC4 PCC5 PCC6 PCC7 PCC8 PCC9 ebicPL mltFL ebicFL
mltPL chill RRD80 RRD250 tups1 tups2 tser1 tser2
Sheet ref
Table 1
11:47:00 AM 10:15:00 PM 12:50:00 PM 04:14:02PM 03:48:00PM
03:26:00PM 01:25:00PM 01:50:00PM 02:51:00PM 03:05:00PM
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
VhHarmonic%,VhHarmonic RMS,AhHarmonic RMS,AhHarmonic%Trend
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Main Incomer 11 kV Main Incomer LT with Full Load Main Incomer
LT side with APFC Main Incomer LT without Chiller Load Chiller 1
RRD 80 kVA UPS Feeder RRD 250 kVA UPS Feeder Thompson UPS 1 Feeder
Thompson UPS 2 Feeder Thompson Server 1 Feeder Thompson Server 2
Feeder
Maximum Harmonic Content details Location
1.478 1.831 1.285 1.761 1.669 1.857 1.954 1.871 1.822 1.694
1.863
U1 THD Avg Max1.7 3 2.1 2.1 2.2 2.1 2.3 2.3 2.6 2.4 2.9
1.436 1.745 1.268 1.691 1.476 1.59 1.74 1.622 1.65 1.541
1.651
U2 THD Avg Max1.6 3 2.5 2 2.3 1.8 2.2 2.4 2.6 2.4 2.9
1.475 1.973 1.454 2.073 1.671 1.882 1.963 1.877 1.86 1.672
1.882
U3 THD Avg Max1.6 3.2 2.7 2.5 2.4 2.1 2.2 2.5 2.7 2.5 3.2
1.482 1.942 1.405 1.997 1.726 1.946 2.032 1.958 1.896 1.726
1.929
V1 THD Avg Max1.7 3.1 2.4 2.4 2.3 2.3 2.3 2.4 2.9 2.4 3.2
1.468 1.726 1.267 1.603 1.536 1.678 1.822 1.709 1.69 1.61
1.729
V2 THD Avg Max1.7 2.9 2.2 1.9 2.1 1.9 2.1 2.2 2.5 2.4 2.9
1.44 1.879 1.399 1.941 1.546 1.708 1.82 1.706 1.737 1.582
1.749
V3 THD Avg Max1.6 3.2 2.7 2.4 2.3 1.9 2.2 2.4 2.8 2.5 3.1
6.21 6.286 6.446 7.388 2.868 108.5 17.593 62.985 103.08 8.371
11.303
A1 THD Avg Max
9.4 8.9 14 9.2 3.8 118.2 22.6 68.2 112.5 13 21
6.928 5.368 5.617 5.966 2.466 104.61 14.477 62.086 100.77 7.408
8.654
A2 THD Avg Max
8.7 9.3 13 8.6 2.8 112.1 18.7 66.9 109.8 11.8 16.1
6.113 5.862 5.503 6.251 2.63 94.225 16.307 59.559 98.564 8.443
9.168
Table 2 A3 THD Avg Max
10.2 8 15.5 9.2 3 99.2 20.4 64.5 106.4 12.7 16.9
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Measured Currents,Short circuit currents Individual Current
harmonics upto h=25 A2 A3 A1h3 A1h5 A1h7 A1h9 A1h11 A1h13 A1h15
A1h17 A1h19 A1h21 A1h23 Perm Location Measured Phase . Currents
Isc/Il A1 THD in THD in THD in in % in % in % in % in % in % in %
in % in % in % in % issibl in Amps % % % e TDD in % A1 A2 A3
Table 3 Perm Permis Permi Permi issibl sible ssible ssible e for
for for for h=3 V1 V2 V3 in % in %Main Incomer 11 kV Main Incomer
LT with Full Load Main Incomer LT side with APFC Main Incomer LT
without Chiller Load 10620.00 421.50 425.50 415.50 10650.00 425.50
428.90 419.40 10660.00 423.90 427.10 417.70 1.70 3.00 2.10 2.10
1.70 3.00 2.50 2.00 1.60 3.20 2.70 2.50 0.30 0.20 0.50 0.20 1.20
2.80 1.90 1.60 1.30 1.70 2.10 2.00 0.00 0.10 0.10 0.10 0.20 0.40
1.60 0.70 0.10 0.10 0.30 0.20 0.00 0.00 0.10 0.10 0.00 0.00 0.10
0.00 0.00 0.00 0.00 0.00 0.10 0.00 0.00 0.00 0.10 0.00 0.00 0.00
5.00 5.00 5.00 5.00 3.00 3.00 3.00 3.00
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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IEEE Std. 519-1992
Table 5
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Bus voltage THD Waveform of 11kV Incomer
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Main Current THD Waveform of 11kV Incomer
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
K Salai, Mylapore, Chennai.
Bus voltage spectrum of 11kV Incomer (h=1 to 10)
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Bus voltage spectrum of 11kV Incomer (h=11 to 16)
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Bus voltage spectrum of 11kV Incomer (h=17 to 27)
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Main Current spectrum of 11kV Incomer (h=1 to 10)
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Main Current spectrum of 11kV Incomer (h=11 to 16)
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Main Current spectrum of 11kV Incomer (h=17 to 27)
Power Quality Study for ACROPOLIS, A R Property Services, 148, R
K Salai, Mylapore, Chennai.
Power factor at 11kV Incomer
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
K Salai, Mylapore, Chennai.
Unbalance current and Voltage in 11kV Incomer
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Line Voltage in 11kV Incomer
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
K Salai, Mylapore, Chennai.
Line Current in 11kV Incomer
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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Power Quality Study for ACROPOLIS, A R Property Services, 148, R
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