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2 ENERGY MANAGEMENT SYSTEM AN OVERVIEW AN OVERVIEW

3 COMMSSION HAD ISSUED DIRECTIVE IN THE TARIFF ORDER OF JUNE 2003 TO PREPARE A TOTAL SCHEME OF ‘ABT’ IN CONSULTATION WITH DISCOMs CLEARLY DEFINING THE RESPONSIBILITY OF EACH LICENSEE AND SUBMIT TO THE COMMISSION.  IN PERSUANCE TO THE ABOVE DIRECTIVE DELHI TRANSCO LTD. HAD FINALIZED THE SCHEME FOR EFFECTIVE IMPLEMENTATION OF ‘ABT’ IN DELHI.  SCHEME HAD BEEN SUBMITTED TO THE COMMISSION.

4 NECESSITY FOR ENERGY MANAGEMENT SYSTEM  AVAILABILITY BASED TARIFF WAS APPROVED BY CERC FOR IMPLEMENTATION TO ACHIEVE GRID DISCIPLINE AND ENSURE QUALITY POWER SUPPLY TO THE CONSUMERS.  AS PER ‘ABT’ EACH LICENSEE IS TO SCHEDULE POWER ON DAY AHEAD BASIS IN 15 MINUTES TIME SLOT BASISAND ENSURE ADHERING TO THE SCHEUDLE ACCEPTED BY SLDC.  FOR EFFECTIVE IMPLEMENTATION OF ‘ABT’ THE INFORMATION OF LOAD DRAWAL ON 15 MINUTES TIME SLOT IS NECESSARY.

5 NECESSITY FOR ENERGY MANAGEMENT SYSTEM CONTD…..  ABT ALSO PROVIDES FOR SELF GENERATION OF REACTIVE POWER BY THE LICENSEE-EFFECTIVELY NO DRAWAL OF REACTIVE ENERGY AT THE DRAWAL POINT.  REACTIVE ENERGY IS ALSO PRICED AS PER THE ORDERS OF THE COMMISSION.  ENERGY DRAWAL WITH FREQUENCY STAMPING AVERAGED OVER 15 MINUTES TIME SLOT IS ALSO REQUIRED FOR LOAD DESPATCH CENTRE OF THE LICENSEES TO TAKE CORRECTIVE ACTION.  THIS IS ONLY POSSIBLE THROUGH AN ONLINE ENERGY MANAGEMENT SYSTEM.

6 OBJECTIVES OF EMS SYSTEM IT IS METERING, SYSTEM BASED ON AVAILABILITY BASED TARIFF CONCEPT TO ACHIEVE: ACTIVE ENERGY  ENERGY CONSUMPTION OF EVERY 15 MINUTES TIME SLOT FOR 96 SLOTS IN A SINGLE DAY.  TO COMPARE THE CONSUMPTION IN 15 MINUTES TIME SLOT WITH THE SCHEDULED ENERGY.  TO DETERMINE OVER DRAWAL & UNDER DRAWAL DURING EVERY 15 MINUTES TIME SLOT.  TO DETERMINE THE AVERAGE FREQUENCY IN 15 MINUTES TIME SLOT COMMUNSURATE WITH ENERGY DRAWAL.  TO DETERMINE THE UI PAYABLE/ RECEIVABLE FOR EACH 15 MINUTES TIME SLOT.  TO COMPUTE SUCH UI FOR 24 HRS. BASIS & THEREAFTER ON WEEKLY BASIS.

7 OBJECTIVES OF EMS SYSTEM CONTD…. REACTIVE ENERGY  TO RECORD LAGGING REACTIVE ENERGY DRAWN BY A LICENSEE FROM TRANSCO AT EXCHANGE POINTS BELOW & UPTO 97PU VOLTAGE.  TO RECORD LEADING REACTIVE ENERGY DRAWN BY A LICENSEE FROM TRANSCO AT EXCHANGE POINTS BELOW & UPTO 97PU VOLTAGE.  TO RECORD LAGGING REACTIVE ENERGY PUMPED INTO THE TRANSCO SYSTEM AT & ABOVE 103PU VOLTAGE AT EXCHANGE POINTS.  TO RECORD LEADING REACTIVE ENERGY PUMPED INTO THE TRANSCO SYSTEM AT & ABOVE 103PU VOLTAGE AT EXCHANGE POINTS.  TO COMPUTE SUCH ENERGY FOR ALL EXCHANGE POINTS AND COMPUTE THEM FOR EACH LICENSEE.

8 COMPONENTS OF THE PROPOSED EMS SYSTEM  COMMUNICABLE, PROGRAMMABLE ENERGY METERS-IMPORT/ EXPORT BASED,0.2 PRECISION-AS MAIN METER TO COMPUTE WATT VAR-FOUR QUARDRANTS VA  CHECK METERS-AS BACKUP TO MAIN METER & ACT AS ENERGY BALANCE METERS  GPS SYSTEM-FOR TIME SYNCHRONISING  POWER QUALITY ANALYSER TO MEASURE: WATT VAR-FOUR QUARDRANT VA VOLTAGE SAG & SWELL HARMONIC CONTENTS EQUIPMENT AT S/STNs.

9 COMPONENTS OF EMS COMPONENTS OF EMS  COMPUTER HARDWARE & MICROPROCESSOR  FREQUENCY SAMPLING DEVICE  LAN & ASSOCIATED HARDWARE FOR READING THE METERS AND POWER QUALITY ANALYSER ETC.  MODEM & COMMUNICATION CARD FOR EXPORTING DATA TO TRANSCO SERVER THROUGH COMMUNICATION HARDWARE SUCH AS GPRS,WIRELESS, TELEPHONE, FIBRE OPTIC ON IEC PROTOCOL.  NEED BASED OFFICE AUTOMATION HARDWARE FOR DATA PROCESSING

10 COMPONENTS OF EMS CONTD..  EQUIPMENT AT TRANSCO CONTROL CENTRE  MODEM & COMMUNICATION HARDWARE FOR RECEIVING DATA FROM VARIOUS S/STNs. THROUGH COMMUNICATION  TRANSMIT PROCESSED DATA FROM TRANSCO SERVER TO LICENSEES COMPUTER THROUGH COMMUNICATION LINK.  OFFICE AUTOMATION HARDWARE FOR DATA PROCESSING/RECORDING.

11  COMPUTER AT LICENSEE END TO RECEIVE & DISPLAY DATA PERTAINING TO POWER & ENERGY OF THE LICENSEE.  MODEM & COMMUNICATION HARDWARE FOR RECEIVING DATA FROM TRANSCO  NEED BASED OFFICE AUTOMATION HARDWARE FOR DATA VIEWING. COMPONENTS OF EMS CONTD.. EQUIPMENT AT LICENSEE END

12 SOFTWARE FOR FOLLOWING USES  READ METERS AND COMMUNICATE DATA TO COMPUTER/ MICROPROCESSOR THROUGH LAN.  COMPUTE ENERGY DATA LICENSEE WISE.  COMMUNICATE DATA ON AVERAGED OVER 15 MINUTES TIME SLOT BASIS TO TRANSCO.  PROCESS DATA AS PER THE APPLICABLE ABT ORDERS WITH 15 MINUTES TIME SLOTAND FREQUENCY STAMPING i.e. ACTIVE ENERGY REACTIVE ENERGY ‘UI’ CHARGES

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14 ENERGY MANAGEMENT SYSTEM OF POWER GRID PROPOSED ENERGY MANAGEMENT SYSTEM OF DELHI TRANSCO LTD. ABT, Check Meters & Power Monitor installed at different Exchange-Points Consumption would be available On-Line in every 15 minutes. Readings would be available on-line, so no further action required. Bill will be totally computerized. DTL would raise the bill of Energy On- Line at the office of different Licensees. NREB prepares REA for raising energy bills.REA is prepared on monthly basis ‘UI’ and Reactive Energy accounts are prepared on weekly basis. SEM Meters installed at Exchange Points Energy consumption of each 15minuts time slot downloaded after seven days. Readings sent to NRLDC through Floppy, CD or NRLDC computes readings and sent to NREB. To different States To Generator companies Time Period: Almost Online As there is no human intervention, it is a fool proof and efficient method of Energy Accounting. Time Period:It takes about 8-10 days to process the readings and make the accounts by RLDC/REB. Due to human intervention this method is time consuming and error prone.

15 COMPARISION OF PROPOSED EMS WITH PGCIL SEM SYSTEM PGCIL SYSTEM BEING USED FOR ABT BILLING IN REGIONAL GRIDS PROPOSED EMS BY DTL 1) OFF LINE1) ON LINE 2) PROCESSING & ACCOUNTING AFTER 7 DAYS. 2) BEING ON LINE PROCESSING AND ACCOUNTING IN EVERY 15 MINUTES TIME SLOT 3) THE CORRECTIVE MEASURES SUCH AS LOAD MANAGEMENT IS NOT PROPER AS THE BEHAVIOUR OF DRAWAL VS SCHEDULED ALLOCATION IN DIFFERENT FREQUENCY SPECTRUM KNOWN ONLY AFTER PROCESSING OF THE DATA DOWN LODED AFTER 7 DAYS. 3) THE CORRECTIVE MEASURES CAN BE APPLIED AFTER EVERY 15 MINUTES.

16 COMPARISION OF PROPOSED EMS WITH PGCIL SEM SYSTEM… CONTD. 4) ‘UI’ ACCOUNT SETTLED IN 7 DAYS. 4) ‘UI’ ACCOUNT SETTLEMENT CAN BE POSSIBLE ON DAILY BASIS. 5)METER ERROR IS KNOWN AFTER PROCESSING THE DOWNLOADED DATA AFTER 7 DAYS. 5) METER ERROR DEDUCTION IS SIMULTANEOUS DUE TO INBUILT SELF CHECK MECHANISM AND ANNOUNCIATION OF CORRECTIVE MEASURES REQUIRED. 6) NO PROVISION OF COMPUTATION OF SIMULTANEOUS DEMAND. 6) COMPUTATION OF SIMULTANEOUS DEMAND OF EACH LICENSEE IS POSSIBLE WHICH IS REQUIRED FOR PROPER LOAD MANAGEMENT.

17 7)AUTOMATIC BILLING IS NOT POSSIBLE 7) AUTOMATIC BILLING WITH NO INTERVENTION OF HUMAN FROM METER READING TO ISSUE OF BILLS EVERY PROCESS IS TOTALLY COMPUTARIZED AND HENCE FULLY AUTOMATIC. COMPARISION OF PROPOSED EMS WITH PGCIL SEM SYSTEM… CONTD…

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