ABT meters

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ABT meters


<p>DIN E ISO 9001: 2000</p> <p>MAHARASHTRA STATE ELECTRICITY TRANSMISSION CO. LTD.PUNE PRESENTATION BY</p> <p>S.M. BAKRE , M.E. , M.M.S.EXECUTIVE ENGINEER400 KV R.S. , Jejuri</p> <p>ON ABT METERS</p> <p>WELCOME</p> <p>Basic Concepts Historical Preview Principle of working Meters Generations First - Ferrari or Electromechanical Second - Static Third - Numeric</p> <p>Electromechanical or Ferrari Meters The First Generation meters based on rotation of Aluminum disk within current coil and pressure coil.</p> <p>Static Meter Advantages High Accuracy Low cost</p> <p> Limitations Not intelligent Tamper can not be detected. Magnetic Theft</p> <p>ABT Meters ABT means Availability based Tariff .</p> <p>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.</p> <p>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.</p> <p>ABT Concept Traditional Concept :dw / dt Modern Concept :dw/df . df/dt dw/df :- ABT Meters df./dt :- Frequency Trend</p> <p>Underfrequency Relay (UFR) UFR Settings 48.8 Hz 48.6 Hz 48.2 Hz</p> <p>Frequency Trend Relay ( FTR )</p> <p>df/ dt Relay</p> <p>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 .</p> <p>ABT tries to improve a quality of power and curtail the following</p> <p> 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.</p> <p>ABT Operation and Billing &amp; Payment Mechanism The SEBs 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.</p> <p>ABT Operation and Billing &amp; Payment Mechanism</p> <p>Based on the declared demand and available supply, the LD provides a schedule to the SEBs and the CGS for drawl and generation in 15-minute blocks.</p> <p>ABT Operation and Billing &amp; Payment Mechanism</p> <p> Based on the drawl and generation positions of the SEBs and the CGS stations, the UI bill is computed.</p> <p>The Three-part ABT Tariff</p> <p> Fixed Charge : This is</p> <p>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</p> <p>The Three-part ABT Tariff</p> <p> Energy Charge: All the</p> <p>scheduled energy that is drawn is charged as per the variable energy charge of the station from which power is being drawn.</p> <p>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.</p> <p>Billed Amount Billed Amount = Fixed Charge + Energy Charge + UI Charge</p> <p>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.</p> <p>ABT Meters Intelligent meters Based on polled approach </p> <p>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 .</p> <p>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 .</p> <p>Sampling of a sinusoidal wave IRMS = ( I1 2+ I2 2 + I3 2 +I4 2 .. +In 2 ) -----------------------------------------------------n</p> <p>VRMS</p> <p> ( V1 2 + V2 2 + V3 2 +V4 2 .. +Vn 2 ) = -----------------------------------------------------n</p> <p>V1 I1 + V2 I2 + V3 I3 +V4 I4 .. +Vn In W = ------------------------------------------------------n W cos = ----------------VRMS IRMS</p> <p>Functional Block Diagram of ABT Meter</p> <p>3 Phase , 4 Wire Meters [ 3 wattmeter method ]</p> <p>3 Phase , 4 Wire Meters</p> <p>W = W1 + W2 + W3 = VI cos + VI cos + VI cos = 3 VI cos </p> <p>General Arrangement</p> <p>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.</p> <p>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.</p> <p>METER TESTING LAB SETUP</p> <p>ZERA</p> <p>ABT Meter Testing Dial Test - No. of blinkings per kWh Accuracy Test 0.2 Min. Current test Max current test</p> <p>Test Terminal Block (TTB)</p> <p>Testing of ABT Meters</p> <p>Manufacturers of ABT meters</p> <p>Status of ABT meters at 400 KV Jejuri SSFeeder / 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</p> <p>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 .</p> <p>Advantages of ABT Meters</p> <p> These meters</p> <p>have higher accuracy of the order of 0.2 .</p> <p>Advantages of ABT Meters</p> <p> These meters are capable of displaying energy as per applicable tariff I.e. TOD and ABT tariff.</p> <p>Advantages of ABT Meters In the advent of load survey data , it is possible to monitor the consumption pattern.</p> <p>Advantages of ABT Meters Using polled approach , the CPU detects abnormality in the metering system.</p> <p>Advantages of ABT Meters</p> <p> The starting current of is very less i.e. 0.1 % of base current. Thus 1 A meter will record 1 mA consumption.</p> <p>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.</p> <p>Advantages of ABT Meters These meters are</p> <p>friendly.</p> <p>user</p> <p> 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 .</p> <p>Advantages of ABT Meters MD can be reset through any of the modes : MRI Manual Laptop Auto</p> <p>Advantages of ABT Meters</p> <p> Remote data retrieval possible through internet and mobile. Can be used in AMR [ Automatic Meter Reading ]</p> <p>OPEN ACCESS, WHEELINGOpen 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.</p> <p>OPEN ACCESS, WHEELINGSuppose 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).</p> <p>4 Quadrant Import Export Meter</p> <p>Q2 Q1 Export Import Lag Lead Q3 Q4 Export Lag Import Lead</p> <p>ABT SpecificationsParameter ValueStandard</p> <p>IEC 687 , CBIP 88Billing Energy</p> <p>DefinitionVoltage RatingTemperature</p> <p>Type of meter 3 phase , 4 Wire400KV to 11KV/110 /3 V27 0C</p> <p>ABT SpecificationsParameterCurrent RatingMaximum Current [ 200 % of Ib ] Minimum Current [ 0.1 % of Ib ] Class Of Accuracy</p> <p>Value1 Amp</p> <p>2 Amp 1 mA 0.2</p> <p>Frequency</p> <p>50 Hz [ +- 5% ]</p> <p>ABT SpecificationsDisplay Parameters 1 ] 3 Voltages - Vr , Vy , Vb 2 ] 3 Currents - I r , Iy , Ib 3 ] Kwh Import &amp; 4 ] Rkvah [ Lead ] Export modes 5 ] Rkvah [ Lag ] 6 ] Kvah 7 ] Date and Time 8 ] Power Factor 9 ] KVA MD</p> <p>ABT Specifications Modes of MD Reset Manual Auto MRI Laptop Mobile Phone Remote end</p> <p>Load Survey Data 60 days data on FIFO Integration period of 15 minutes LS reset available LS Parameters 3 Voltages 3 Currents Ir , Iy , IbVr , Vy , Vb</p> <p> Date and Time</p> <p> kWh</p> <p> RKVAH [ Lag ] RKVAH [ Lead ]</p> <p>KVAH KVA [ MD ]Pf</p> <p>Load Survey Data [ Graphical ]</p> <p>Tamper Data Meter CPU generates tamper events on polled approach. At least 320 tamper events should be memorized.</p> <p> Current Tamper CT Reverse CT Short CT Unbalance</p> <p>Tamper Data Voltage Tamper PT Missing PT Low</p> <p> Power Tamper Meter bypass</p> <p>ABT Specifications Minimum retention time for NV RAM &gt;= 10 Years Total Energy for billing = true energy + harmonic energy Principle of working sampling PCB SMT [ Surface mounting technology ]</p> <p>Surface Mount Technology [ SMT ] Lesser heat dissipation Long life of PCB and Components No component disconnection due to dry solder.</p> <p>MRI METER READING INSTRUMENT</p> <p>SANDS MRI</p> <p>Specifications of MRIstandard IEC 1109 CBIP 111 ANSI UART , RS-232 , RS-485 130 bps [ bits per second ] to 115 Kbps. 7.2 Volts , 800 mah Nickel Cadmium battery Communication rate of data transfer</p> <p>Battery</p> <p>Storage Capacity</p> <p>8.5 MB</p> <p>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 .</p> <p>MRI Commands DOS Commands DIR Date Time CLS Ver Vol Path Firmware Commands Master import Master export PC_Term SH TP MSZ TPRMRM</p> <p>The following disturbances are recorded by ABT meter :-</p> <p> Harmonics Voltage dips and short interruptions Conducted transients DC &amp; AC magnetic fields Electromagnetic fields Electromagnetic discharge</p> <p>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 &amp; outgoing feeders / transformers / ICTs .</p> <p>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.</p> <p>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.</p> <p>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.</p> <p>Pin ConfigurationNo 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</p> <p>Pin ConfigurationNo 11 12 13 14 15 Pin Vac(L) Vac(N) Vdc(+) Vdc(-) Description Auxiliary AC Supply ( Live ) Auxiliary AC Supply ( Neutral ) Auxiliary DC Supply ( Positive ) Auxiliary DC Supply ( Negative ) Earth connection</p> <p>Reports Generation PC Software Instantaneous Data Billing Data Load Survey Data Tamper Data</p> <p>Reports generated by EMS Energy Loss Report Voltagewise Energy Loss Report Transformerwise Energy Loss Report Power ON/OFF Report Voltage Profile Report</p> <p>Reports generated by EMS Min-Max report for current , voltage , MW , MVAR , PF &lt; frequency. Transformer Loading Report Alarm Report. Meter Replacement Report Load Survey Report Load Shedding Report [ manual data entry ] Meter Detail Report</p> <p>CEA Regulations on Installation &amp; Operation of meters</p> <p> MEAA Meter for energy audit &amp; accounting MIT -Meter for interface tariff MC - Meter for Consumer</p> <p>ABT Metering in MSETCL Interstate ABT Metering Intra-state ABT Metering No of ABT / MFM meters = 9000 No. of interface locations = 1500</p> <p>Basics of Tulip Communication</p> <p>Network Connectivity Devices Modems Repeaters Hubs Bridges Multiplexers Switches Routers Brouters</p> <p>Clint Server Model</p> <p>Modem Performs modulation and demodulation</p> <p>Repeater Perform amplification of the signal to reduce attenuation.</p> <p>Hubs Hub is the multiport repeater</p> <p>Connects two different networks</p> <p>Bridge</p> <p>Multiplexer ( MUX )</p> <p> Combines two or more signals on high speed transmission media</p> <p>Switches Connec...</p>