report 240612

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

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The relevant extract regarding Harmonics from The Central Electricity Authority (Technical

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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.

Study Conducted by Interface Electronics Pvt Ltd, Chennai

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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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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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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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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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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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IEEE Std. 519-1992

Table 5


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Bus voltage THD Waveform of 11kV Incomer


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Main Current THD Waveform of 11kV Incomer


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Bus voltage spectrum of 11kV Incomer (h=1 to 10)


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Main Current spectrum of 11kV Incomer (h=1 to 10)


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Power factor at 11kV Incomer


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Unbalance current and Voltage in 11kV Incomer


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Line Voltage in 11kV Incomer


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Line Current in 11kV Incomer


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report 240612

Documents

interface

thompson ups2

power quality

bus voltage

electrical

main current

ahharmonictrend

11kv power