abt meter

DIN E ISO 9001: 2000

MAHARASHTRA STATE ELECTRICITY TRANSMISSION CO. LTD.PUNE PRESENTATION BY

S.M. BAKRE , M.E. , M.M.S. EXECUTIVE ENGINEER 400 KV R.S. , Jejuri

ON ABT METERS

WELCOME

Basic Concepts • Historical Preview • Principle of working • Meters Generations • First - Ferrari or Electromechanical • Second - Static • Third - Numeric

Electromechanical or Ferrari Meters • The First Generation meters based on rotation of Aluminum disk within current coil and pressure coil.

Static Meter • Advantages • High Accuracy • Low cost

• Limitations • Not ‘ intelligent ‘ Tamper can not be detected. • Magnetic Theft

ABT Meters • ABT means Availability based Tariff .

The term ‘Availability’ of ABT • Indicates that the power MW should be available. • It may specifically be noted that energy charge (at the specified plantspecific rate) is not based on actual generation and plant output, but on scheduled generation.

Availability as a base • For example if the rated capacity of generator is 50 MW out of which 30 MW generation is available , the base for billing would be 30 MW and not 50 MW. 30 MW would be scheduled generation for calculating deviation if any. If 20 MW power is generated instead of scheduled 30 MW , the penalty of 30-20 = 10 MW would be imposed as UI charge.

ABT Concept • Traditional Concept :dw / dt • Modern Concept :dw/df . df/dt • dw/df :- ABT Meters • df./dt :- Frequency Trend

Underfrequency Relay (UFR) • • • •

UFR Settings 48.8 Hz 48.6 Hz 48.2 Hz

Frequency Trend Relay ( FTR )

•df/ dt Relay

Implementation of ABT was recommended initially at Central Generating Stations in the year 1994 by M/s ECC of USA under the study sponsored by World Bank and Asian Development Bank .

ABT tries to improve a quality of power and curtail the following

• Unacceptable rapid and high frequency deviations • Frequent grid disturbances which result in generator tripping , power outages and grid instability. • The pricing of power is made frequency dependent by ABT.

ABT Operation and Billing & Payment Mechanism • The SEB‟s give the LD its requirement in 15-minute blocks for the next day. • At the same time the CGS stations also provide the LD their 15-minute availability positions.

ABT Operation and Billing & Payment Mechanism

Based on the declared demand and available supply, the LD provides a schedule to the SEB‟s and the CGS for drawl and generation in 15-minute blocks.

ABT Operation and Billing & Payment Mechanism

• Based on the drawl and generation positions of the SEBs and the CGS stations, the UI bill is computed.

The Three-part ABT Tariff

• Fixed Charge : This is

payable by the beneficiary states based on the capacity allocated to them, and is irrespective of the amount of power they draw or schedule to draw

The Three-part ABT Tariff

• Energy Charge: All the

scheduled energy that is drawn is charged as per the variable energy charge of the station from which power is being drawn.

The Three-part ABT Tariff • UI Charge : The UI

(Unscheduled Interchange) charge is levied on those units of energy that are a deviation from the schedule. This UI charge is frequency dependent.

Billed Amount • Billed Amount = Fixed Charge + Energy Charge + UI Charge

The energy is metered in 15-minute time blocks, since frequency keeps changing (and the UI rate with it). The metered energy is then compared with the scheduled energy for that 15minute time block, and the difference (+ or -) becomes the UI energy. Corresponding UI rate is determined by taking the average frequency for the same 15-minute time block into account.

ABT Meters • „ Intelligent „ meters • Based on „polled approach „

Principle of working of ABT meter • The energy is recorded in terms of pulses per kWh . The principle of working of static ABT meter is sampling . The voltage and current singles are received from PT and CT respectively .The samples of these signal at a particular instant are collected by Sample and Hold circuit . The phase difference between voltage and current is also found out . These values are analogue values .

Principle of working of ABT meter • The CPU [ Central Processing Units ] only accepts digital signals . Therefore , the analogue signals are converted to digital by the circuit called ADC [Analogue to digital converter].The CPU processes these input signals for finding KVA [VI] , kWh [ VI cos  ] , RKVA [ VI sin  ] and other parameters . In order to measure the energy in terms of units , the circuit Energy to frequency converter is provided. The energy is converted into pulses . The counter counts number of pulses .

Sampling of a sinusoidal wave IRMS =

VRMS

 ( I1 2+ I2 2 + I3 2 +I4 2 ……….. +In 2 ) -----------------------------------------------------n

 ( V1 2 + V2 2 + V3 2 +V4 2 ……….. +Vn 2 ) = -----------------------------------------------------n

V1 I1 + V2 I2 + V3 I3 +V4 I4 ……….. +Vn In W = ------------------------------------------------------n W cos  = ----------------VRMS IRMS

Functional Block Diagram of ABT Meter

3 Phase , 4 Wire Meters [ 3 wattmeter method ]

3 Phase , 4 Wire Meters

W = W1 + W2 + W3 = VI cos  + VI cos  + VI cos  = 3 VI cos 

General Arrangement

General arrangement • Keypad - 12 numeric plus * and # keys. • LCD Display – 4 row X 20 characters • Optical Port – RS232 electrically apart • Metering Module – with sliding guides. • Calibrated LEDs – for dial test. • MD Reset button sealable • RJ-11 Port - RS-485 interface with MODBUS.

METER TESTING LAB SETUP • Program the AC Power Source to generate a particular waveform. • Configure the reference meter. • Set the pulse counter to zero. • Turn ON / OFF the switch I at the beginning / end of the test. • Record results and make calculations.

METER TESTING LAB SETUP

ZERA

ABT Meter Testing • Dial Test - No. of blinkings per kWh • Accuracy Test 0.2 • Min. Current test • Max current test

Test Terminal Block (TTB)

Testing of ABT Meters

Manufacturers of ABT meters

Status of ABT meters at 400 KV Jejuri SS Feeder / ICT 400 KV Lonikand 400 KV Stg IV ICT – HV Side ICT – LV Side 220 KV Baramati 220 KV Jejuri I 220 KV Jejuri II 220 KV Phursingi

Type MFM MFM ABT ABT MFM MFM MFM MFM

Category T2T T2T T2T T2T T2T T2T T2T T2T

Advantages of ABT Meters • These meters are capable of storing data . Therefore , the features such as load survey , energy history , tamper data etc is available. If the meter is stopped or tampered , the evidence is recorded .

Advantages of ABT Meters

• These meters

have higher accuracy of the order of 0.2 .

Advantages of ABT Meters

• These meters are capable of displaying energy as per applicable tariff I.e. TOD and ABT tariff.

Advantages of ABT Meters • In the advent of load survey data , it is possible to monitor the consumption pattern.

Advantages of ABT Meters • Using polled approach , the CPU detects abnormality in the metering system.

Advantages of ABT Meters

• The starting current of is very less i.e. 0.1 % of base current. Thus 1 A meter will record 1 mA consumption.

Advantages of ABT Meters • The ABT meters have self diagnostic feature by which any error developed in the inside component can be detected. This feature checks that the data stored in the meter is safe and not corrupt.

Advantages of ABT Meters • These meters are

friendly.

user

• The display parameters are easy to understand. • Push button operation to read display parameters is easy. • Data retrieval through MRI [ Meter Reading Instrument ] is simple .

Advantages of ABT Meters • MD can be reset through any of the modes :• MRI • Manual • Laptop • Auto

Advantages of ABT Meters

• Remote data retrieval possible through internet and mobile. • Can be used in AMR [ Automatic Meter Reading ]

“OPEN ACCESS”, “WHEELING” “Open access” and “wheeling” generally involve two parties, one supplying a certain quantum of power to the other through the regional / State grid. Any such transaction involves a number of parties, and disputes could arise in scheduling, energy accounting and commercial settlement, unless an appropriate framework is in place.

“OPEN ACCESS”, “WHEELING” Suppose party - A has contracted to supply 10 MW round the clock to party B (in the same State) at a certain price (which need not be disclosed to others), through the State grid. Suppose the transmission loss apportioned to this transaction has been determined as 0.5 MW. Party - B would then be entitled to receive 9.5 MW, provided party - A is actually injecting 10.0 MW into the State grid at its end. In actual operation, both injection by A and drawl by B may fluctuate over the day and the differential may vary from 0.5 MW. Who would pick up the commercial liability arising on account of these deviations? Since A and B are physically apart and operationally independent, a pragmatic solution for commercial treatment in such a case would be to meter the actual injection of A and actual drawl of B in 15-minute time blocks, and separately compute their deviations from their respective schedules (10.0 MW / 2.5 MWh for A and 9.5 MW / 2.375 MWh for B).

4 Quadrant Import Export Meter

Q2 Q1 Export Import Lag Lead Q3 Q4 Export Lag Import Lead

ABT Specifications Parameter Value Standard

IEC 687 , CBIP 88

Definition

Billing Energy

Type of meter 3 phase , 4 Wire Voltage Rating

400KV to 11KV/110 /3 V

Temperature

27 0C

ABT Specifications Parameter

Value

Current Rating

1 Amp

Maximum Current [ 200 % of Ib ] Minimum Current [ 0.1 % of Ib ] Class Of Accuracy

2 Amp

Frequency

1 mA 0.2

50 Hz [ +- 5% ]

ABT Specifications Display Parameters 1 ] 3 Voltages - Vr , Vy , Vb 2 ] 3 Currents - I r , Iy , Ib 3 ] Kwh Import & 4 ] Rkvah [ Lead ] Export modes 5 ] Rkvah [ Lag ] 6 ] Kvah 7 ] Date and Time 8 ] Power Factor 9 ] KVA MD

ABT Specifications • Modes of MD Reset • • • • • •

Manual Auto MRI Laptop Mobile Phone Remote end

Load Survey Data • 60 days data on FIFO • Integration period of 15 minutes • LS reset available

• LS Parameters • 3 Voltages –

Vr , Vy , Vb

• 3 Currents – Ir , Iy , Ib

• Date and Time

• kWh

• RKVAH [ Lag ] RKVAH [ Lead ]

KVAH KVA [ MD ] Pf

Load Survey Data [ Graphical ]

Tamper Data • Meter CPU generates tamper events on polled approach. • At least 320 tamper events should be memorized.

• Current Tamper • CT Reverse • CT Short • CT Unbalance

Tamper Data • Voltage Tamper • PT Missing • PT Low

• Power Tamper • Meter bypass

ABT Specifications • Minimum retention time for NV RAM >= 10 Years • Total Energy for billing = true energy + harmonic energy • Principle of working – sampling • PCB – SMT [ Surface mounting technology ]

Surface Mount Technology [ SMT ] • Lesser heat dissipation • Long life of PCB and Components • No component disconnection due to dry solder.

MRI – METER READING INSTRUMENT

SANDS MRI

Specifications of MRI standard

IEC 1109 CBIP 111 ANSI

Communication

UART , RS-232 , RS-485

rate of data transfer

130 bps [ bits per second ] to 115 Kbps.

Battery

7.2 Volts , 800 mah ‘Nickel Cadmium ‘ battery

Storage Capacity

8.5 MB

Maintenance of MRI • Charging of MRI is the main maintenance activity to be carried out. For 8 hour working , the MRI should be charged for 1 hour. • If the MRI is not in use , it should be charged once in a week . • It should be checked at least within a month that all MRI commands are working properly . • Clean the surface of MRI with smooth wet cloth .

MRI Commands • DOS Commands • DIR • Date • Time • CLS • Ver • Vol • Path

• Firmware Commands • Master import • Master export • PC_Term • SH • TP • MSZ • TPRMRM

The following disturbances are recorded by ABT meter :-

• · Harmonics • · Voltage dips and short interruptions • · Conducted transients • · DC & AC magnetic fields • · Electromagnetic fields • Electromagnetic discharge

Energy Management Software EMS • The EMS is provided at all substations , Central Monitoring Station [ LD ] , Corporate / Zone / Circle / Division Office . The EMS is implemented for monitoring energy at interface points with inter-state / intra-state grid including all incoming & outgoing feeders / transformers / ICTs .

Energy Management Software EMS • The ABT / MFM meters are installed at the required points . The system software automatically collects data from these meters . The metering system is provided with RS485 communication port [ in form of RJ11 connector on its back ] . The communication cable has RJ11-toRJ11 configuration. The data is collected online on RS485 MODBUS protocol.

Energy Management Software EMS • The data is made available at substations at the refreshing rate of 5 min using multiplexer or Data Concentrator Unit [ DCU ] and interfacing devices. The DCU stores 5 min. data for 30 days [ on FIFO ] basis . The reports can be generated. The EMS at LD has an access to their existing database i.e. Oracle 10g.

The system comprises of the following components • • • • • •

Energy meters [ ABT and MFM ] at each substation. Data Concentrator Unit [ DCU ] at each substation. Global Positioning System [ GPS ] on PC at each substation. Data Acquisition Software [ DAS ] at each substation MYSQL as backend database. Networking [ switches and cables ] at each substation. EMS at LD with access to their existing database i.e. Oracle 10g as backend.

Pin Configuration No 1 2 3 4 5 6 7 8 9 10

Pin VR VY VB IRIN IROUT IYIN IYOUT IBIN IBOUT VN

Description Red Phase Voltage Yellow Phase Voltage Blue Phase Voltage Red Phase Current IN Red Phase Current OUT Yellow Phase Current IN Yellow Phase Current OUT Blue Phase Current IN Blue Phase Current OUT System neutral

Pin Configuration No 11 12 13 14 15

Pin Vac(L) Vac(N) Vdc(+) Vdc(-) г

Description Auxiliary AC Supply ( Live ) Auxiliary AC Supply ( Neutral ) Auxiliary DC Supply ( Positive ) Auxiliary DC Supply ( Negative ) Earth connection

Reports Generation • PC Software • Instantaneous Data • Billing Data • Load Survey Data • Tamper Data

Reports generated by EMS • Energy Loss Report • Voltagewise Energy Loss Report • Transformerwise Energy Loss Report • Power ON/OFF Report • Voltage Profile Report

Reports generated by EMS • • • • • • •

Min-Max report for current , voltage , MW , MVAR , PF < frequency. Transformer Loading Report Alarm Report. Meter Replacement Report Load Survey Report Load Shedding Report [ manual data entry ] Meter Detail Report

CEA Regulations on Installation & Operation of meters

• MEAA – Meter for energy audit & accounting MIT -Meter for interface tariff MC - Meter for Consumer

ABT Metering in MSETCL • • • •

Interstate ABT Metering Intra-state ABT Metering No of ABT / MFM meters = 9000 No. of interface locations = 1500

Basics of Tulip Communication

Network Connectivity Devices • • • • • • • •

Modems Repeaters Hubs Bridges Multiplexers Switches Routers Brouters

Clint – Server Model

Modem • Performs modulation and demodulation

Repeater • Perform amplification of the signal to reduce attenuation.

Hubs • Hub is the multiport repeater

Bridge

•Connects two different networks

Multiplexer ( MUX )

• Combines two or more signals on high speed transmission media

Switches • Connects / disconnects internet connectivity

Routers •Intelligent switches

Brouters • Routers that follow all protocols

Ethernet Cable

RJ-11 Connector

Tulip Communication System

Ensure that

• Proper earthing is done. • Network switch is ‘ ON ‘ • UPS is ‘ ON ‘

How to test Tulip connectivity ? • Contact ‘ ABT Room ‘ at SLDC , Kalwa • At Substation end , make following operations on ABT PC – • Click on ‘ Start ‘ button . • Click on ‘ Run ‘ • Type the word ‘ CMD’ and click ‘ OK ‘ . • Type ‘ IPCONFIG ‘ and press enter button. • Type ‘ PING_code ‘ and press enter button. • The indication ‘healthy ‘ indicates healthiness of the Tulip link.

Check tulip configuration • Visit the following website :www.myconnect.tulipconnect.com • Enter the following :username :- 6086 password :- satisfaction

Maintenance of ABT-Tulip System • AC/DC supply of PC / DCU /Tulip Devices should not be switched off in any case. • The power points should be dedicated and should not be used for other purpose such as mobile charging . • GPS should be always charged and running • The clock of meter /PC/MRI should be accurate and as per GPS.

Maintenance of ABT-Tulip System • Ping test should be conducted daily to ensure that the data is transmitted to SLDC Kalwa at ping 172.16.0.1 • Any change in CTPT ratio should be configured in ABT meter and PC. The CC tool should be used for this purpose. • No new transformer should be taken in service without ABT Configuration .

Maintenance of ABT-Tulip System • The wiring should be proper and should not be disturbed. • The installation should be neat-clean and free from dust. • In case AC supply is to be switched off , the PC should be shut down properly. • In case of CT/PT/ meter failure , proper assessment of energy should be done.

Maintenance of ABT-Tulip System • Data should be retrieved using MRI on first date of the month particularly in respect of T2G feeder.

Problems with ABT / Tulip • ‘ No display ‘ problem.

• • • •

Delay in Report Generation MRI / MRI Software / Training not given PC not working . Antivirus not installed. The Tulip link is not healthy .

Problems with ABT • Energy Audit of Lines is not calculated. • Power ON/OFF Reports - EHV Substations have bus PT and not line PT. Therefore the logic should be only ‘ Current OFF ‘ and not ‘ Voltage OFF ‘ or ‘Power OFF ‘ . • ABT meters operate on auxiliary AC/DC supply . However , at almost all substations , ABT meters are connected on DC . This may create problem when there is DC leakage.

Problems with ABT • UPS of ABT trips on overvoltage / undervoltage at EHV substations . Therefore , it is required to provide stabilizer instead of UPS.

Roadblocks in ABT meter commissioning • At generating stations , the LV of generating transformer is connected directly to 33 KV bus. No CT / PT are provided. • There is no adequate space in switchyard for providing CT/PT. • Metering core not available in CTs. • 5 A CT are provided and not 1 A. • It is difficult to install ABT meter on outdoor panels.

Commissioning of RTU • RTU – Remote terminal Units • DC – data concentrators • Contract given to M/s Siemens vide MSETCL/CO/CE/CRA/RTU/T-0907/7088 dt 31-5-08.

AMR

Connectivity with ERP System • The Data Centers of ERP are connected to Tulip Hub at SLDC kalwa . • The substations are connected to Tulip Hub. • The rate of data transfer is 4 mbps.

• The connectivity is established through following servers – • - ISP Router • ( Internet Service Provider ) • - Tulip intra-net service provider router .

Connectivity with ERP System • Connectivity with Proxy Server • Internet Explorer > • Internet Options > • Connections > • LAN Settings • Enter IP address of Proxy server and Port number

TOD Meters

TOD Tariff TOD Shift Slot A 22.00-6.00 -0.75 per Kwh B 6.00 – 9.00 0 C 9.00 – 12.00 +0.60 per Kwh 12.00 – 18.00 0 B 18.00 – 22.00 1.00 per Kwh D Surcharge /incentive

HT Metering Kiosk

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