Validation of Generation Meter Data in MV-90 xi - Itron, Inc. · Itron Utility Week - October 2013 2 AGENDA • ERCOT Overview • Metering in the ERCOT Market • EPS Meter Data

Validation of Generation Meter Data in

MV-90 xi

Patrick Vinton Supervisor, Meter Data Acquisition &

Renewable Energy Credit Trading Programs

Itron Utility Week

October, 2013

2 Itron Utility Week - October 2013

AGENDA

• ERCOT Overview

• Metering in the ERCOT Market

• EPS Meter Data Collection

• Validation Requirements

• Meter Events – Important?

• Specific Validation Examples

• Results of Validation Checks

• Reference Information

• Questions?


ERCOT Overview

4

ERCOT Timeline

Itron Utility Week - October 2013

History of the Electric Reliability Council of Texas (ERCOT)

• 1941 – Utilities band together to aid war effort

• 1970 – Texas Interconnected System (TIS) forms ERCOT to comply with

North American Electric Reliability (NERC) requirements

• 1981 – ERCOT assumes central operating coordinator role

• 1995 – Texas legislature votes to deregulate wholesale generation

• 1996 – ERCOT becomes first Independent System Operator (ISO) in US

• 1999 – Legislature votes to deregulate retail electric market

• 2001 – Ten control centers merged into one control center

• 2002 – Retail electric market opens, enabling customer choice for 6.1 million

• 2010 – ERCOT implements Nodal Markets

• 2012 – ERCOT has about 600 employees and an annual budget of about

$170 million

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ERCOT Quick Facts


• Market size: about $34 billion

• All generation data is collected and processed using

MV-90 xi

• ERCOT covers 75% of Texas land

• ERCOT handles 85% of Texas load (23 million consumers)

• More than 40,500 miles of transmission lines

• 550+ generation units (more than 74,000 MWs of capacity)

• Peak Demand in ERCOT was set on August 3, 2011 at 68,305

MWs

• Physical assets are owned by transmission providers and

generators, including Municipal Utilities and Cooperatives

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ERCOT Quick Facts


Responsibilities:

The Texas Legislature restructured the Texas electric market in

1999 by unbundling the investor-owned utilities and creating

retail customer choice in those areas, and assigned ERCOT four

primary responsibilities:

• System reliability – planning and operations

• Open access to transmission

• Retail switching process for customer choice

• Wholesale market settlement for electricity production and

delivery.

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The Texas Competitive Model


Generation T&D (“Wires”) End Users

REP

Retailers

REP

Competitive Production Regulated Open Access Competitive Sales

8

ERCOT is one of 10 North American ISOs/RTOs


ISOs/RTOs serve 67% of U.S. population with the goal of providing:

• Reliability

• Efficiency

• Transparency

• Impartiality

ERCOT connections to other grids are limited to direct

current (DC) ties, which allow control over flow of electricity.

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ERCOT Footprint



Metering in the ERCOT Market

11

ERCOT Polled Settlement (EPS) Meter

• Generation metering points

– Transmission Connected

– Distribution Connected (optional)

• Non-Opt-in-Entity (NOIE) metering points

– Bi-directional

– Radial point (optional)

Meter Types


TDSP Metered & Read

• Distribution Connected Generation (can be EPS)

• Radial NOIE Metering point (can be EPS)

• Competitive Loads

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• TDSP Approves Meter Type, as long as it

conforms with;

– ERCOT Protocols

– Applicable ANSI Standards

– Settlement Metering Operating Guide (SMOG)

EPS Meters


• Back-up Meters

– Required (with a couple minor exceptions)

– Same or different manufacturer/type/model


EPS Meter Data Collection

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1250 meters with 19 Different Utilities

EPS Meter Data Collection


– Austin Energy

– AEP-Central

– AEP-West Texas

– Brazos Electric

– Big Country Co-op

– Bryan Texas Utilities

– College Station Utilities

– City Public Service San Antonio

– Denton Municipal Electric

– Garland Electric

– Greenville Electric Utility System

– Lower Colorado River Authority

– Brownsville Public Utilities

– CenterPoint Energy

– Sharyland Electric

– South Texas Electric Co-op

– Texas Municipal Power Authority

– Texas-New Mexico Power Co

– Oncor

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• Performed DAILY by ERCOT

– 7 days a week (yes, weekends AND holidays!)

• Validation, Editing and Estimation (VEE)

– ERCOT Protocols

– Settlement Metering Operating Guide

– Uniform Business Practices (UBP)

• 19 TDSP’s must assist ERCOT in repairing metering

issues and correcting missing or bad data

EPS Meter Data Collection – continued



Validation Requirements

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Why do Extensive Validation of your Meter Data?

Validation, Editing & Estimation (VEE)


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• Per ERCOT Protocols Section 11.1.4, the validation

process will include, but not be limited to, the

following tests:

– Flagging of intervals with missing data;

– Exception reporting if the total number of zero values for any

channel exceeds the tolerance limit;

– Exception reporting if the total number of power outage intervals

exceeds the tolerance limit;

– Channel level exception reporting if any single interval breaches the

upper or lower threshold of the limit;

– Channel level validation of the percent change between two

consecutive intervals being greater than the established tolerance

limit;

Validation, Editing & Estimation (VEE)


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• Per ERCOT Protocols Section 11.1.4, the validation

process will include, but not be limited to, the

following tests:

– Data overlap validation test, which rejects validations when the

current interrogation of data overlaps data previously collected;

– Channel level energy tolerance test, which reports exceptions of

total energy accumulated from the interval data not being equivalent

to the energy calculated from the meter register’s start and stop

readings;

– Validation that the number of expected intervals equals the number

of actual intervals collected during the interrogation process; and

– Validation of data between primary, backup and check meters

where available.

Validation, Editing & Estimation (VEE) – continued


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• What check in MV-90 xi is this?

– Flagging of intervals with missing data;

• Missing data

– Exception reporting if the total number of zero values for any channel

exceeds the tolerance limit;

• Zero Interval Tolerance

– Exception reporting if the total number of power outage intervals exceeds

the tolerance limit;

• Power Outage Interval Tolerance

– Channel level exception reporting if any single interval breaches the upper

or lower threshold of the limit;

• High/Low Limit (Demand)

– Channel level validation of the percent change between two consecutive

intervals being greater than the established tolerance limit;

• Interval Percent (%) Change



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• What check in MV-90 xi is this?

– Data overlap validation test, which rejects validations when the current

interrogation of data overlaps data previously collected;

• Data overlap

– Channel level energy tolerance test, which reports exceptions of total

energy accumulated from the interval data not being equivalent to the

energy calculated from the meter register’s start and stop readings;

• Usage/Energy Tolerance

– Validation that the number of expected intervals equals the number of

actual intervals collected during the interrogation process;

• Interval Tolerance

– Validation of data between primary, backup and check meters where

available.

• Redundant Channel Tolerance




Meter Events

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• AC Power Down

• AC Power Up

• Power Outage (Pulse Status

Report)

• Lapse in Data (Pulse Status

Report)

• Battery Failure

• Start of Test Mode

• End of Test Mode

• RAM Buffer Overflow

• Watchdog Timer Error/Reset

• Time Tolerances

Events in Support of Validating Data


• The following events are also reviewed

by the MV-90 xi Operator;

• Phase Drop-out

• Phase Failure

• Phase Angle Limit

• Phase Restoration

• Potential A Inactive

• Potential B Inactive

• Potential C Inactive

• D80 Interval Errors (fatal errors

on ION meters)


Specific Validation Examples

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Zero Interval Tolerance


• Used to Detect the following;

– When the number of intervals containing a value of

zero exceeds a defined number

• Base Load units generally should not have any zero

intervals

• Non-Base Load units can have zero values and the

tolerance value will be unit specific

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Zero Interval Tolerance – continued


• GOOD for;

– Base Load Units

• Nuclear Plants

• Coal Plants

• Any unit with an excepted steady energy curve

• NOT GOOD for;

– Peaker Units

– Pumping/Switching Units

– Weather Sensitive Units (wind, solar, etc)

• Defined in Channel Master File

27

Zero Interval Tolerance – continued


Which meter is a good candidate for this check?

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High/Low Limit (Demand)


• Monitors an Interval’s Maximum and Minimum value

– Ensures equipment in metering circuit is not being

overloaded or exceeding circuit’s design capacity

– Catches erroneous spikes/dips in data

– Identify energy flow on a line that should not have energy

flow


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High/Low Limit (Demand) – continued


• Interval Max: Max Capacity of Metering Point +10%

• Interval Min: Depends on unit type, i.e., Base Load

units may be set to fail if the interval value drops below

75% of previous 3 years average value.

– Non-Base Load Units may not use this check.

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• Interval Max: Max Capacity of Metering Point +10%,

i.e.,

– 850MW Unit = 935MW (850+85=935)

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• Interval Min: Depends on unit type, i.e., Base Load units

may be set to fail if the interval value drops below 75% of

previous 3 years average value.

– Is unit specific

– Non-Base Load Units may not use this check if the unit regularly

drops to zero

• For this unit, anything below 1200MW is set to fail validation

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Interval Percent (%) Change


• Used to Detect the following;

– Ramp rate exceeds specifications

• Nuclear & Coal Plants generally have slower ramp

rates than Gas or Weather-Sensitive Units

– Loss of Phase (LOP) or Transformer

• Balanced circuits would see a 33% drop

– Setting this tolerance to 25% would catch a LOP or

a loss of a Current Transformer

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Interval Percent (%) Change – continued


• GOOD for;

– Base Load Units

• Nuclear Plants

• Coal Plants

• Any Relatively Steady Energy Curve

• NOT GOOD for;

– Peaker Units

– Pumping/Switching Units

– Weather Sensitive Units (wind, solar, etc)


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Interval Percent (%) Change – continued


Which meter is a good candidate for this check?

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Redundant Channel Tolerance


• Compares, on an Interval-by-Interval basis, the KW

(demand) values between a “PRIMARY” meter and the

designated “BACKUP” meter that shares the same

electrical connection

• Ensures a backup data source where data is deemed

financially critical, such as;

– Grid-Level Monitoring

– Generators

– Inter-Tie Points

• Helps identify meter problems at “critical” points in the Utility Grid

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Redundant Channel Tolerance - continued


There are two (2) options in MV-90 xi

–“Absolute Difference”

–“Channel Tolerance %”

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• “Absolute Difference” Option

– ERCOT uses this option when comparing interval data between 2 meters

– Absolute Difference is in KW

• This is the ‘Absolute Difference’ the 2 meters can differ

on an interval-by-interval basis and still pass Validation


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39



• Factors ERCOT uses to determine “Absolute

Difference” value:

– Meter Point Capacity

– Meter Uncertainties

– Allowable Time Drift between meters

– Transformer Uncertainties (PT’s and CT’s)

• Meter Point Capacity x (meter uncertainties + allowable time drift between meters + PT uncertainty + CT uncertainty) – PT and CT uncertainties can be ignored if BOTH

meters share the same transformers as any error will effect both meters in the same direction

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• Example:

– Meter Point Capacity = 850 MW

– Meter Uncertainties = 0.15% (per meter)

– Allowable Time Drift = 1% of Interval Length (9 seconds per meter)

– Transformer Uncertainties = N/A as they are shared

850 x (0.3% + 2% + N/A) =

850 x 2.3% = 19.55 MW (19,550 KW)

• For this meter point, the meters can differ up to 19.55MW and meet all accuracy requirements

As MV-90 xi is in KW, the value entered in the channel master file would be 19550

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For this meter point, the meters can differ up to 19.55MW and meet all accuracy requirements

But the actual difference is 24.1MW, thereby failing the redundant validation check

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• “Channel Tolerance %” Option

– This option is used when comparing channels

within the SAME meter to identify issues such as

a loss of a current transformer, i.e.,

• If current channels are programmed in meter

channels 5-7, compare Chan 5 to Chan 6, Chan 6

to Chan 7

– Using 25% would catch a loss of a current

transformer or a meter issue


43

Redundant Channel Tolerance (Helpful Hints)


• The “Channel Tolerance %” method does not work well

on pulse meters when the pulses per interval are low • Example: tolerance set to +/-5%. If one meter has 10

pulses and another meter has 9 pulses, there is a 10%

difference and the validation check fails

• IF Possible, use the same meter type for the Backup

meter and program it the SAME as the Primary meter

• Editing: do not have to scale data because of different

multipliers when editing/copying from one to the other

• Set “Call Time” in Backup Meter’s Master File to dial

BEFORE the Primary Meter

• If Primary dials first, the Redundant Check will fail as

there is no Backup meter data to compare to.

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Results of Validation Checks


•EPS Meter Data is the Baseline data in which the ERCOT

Market settles

•All “Load” Data is matched to Generation Data

•Key Performance Indicator (KPI) requirement is that >99.5%

of EPS Meter Data remain unchanged after the settlement

process occurs

•Tracked by Quarter and YTD

•2012 Year-End – 99.89200%

•For 2013;

•1St Qtr 2013 – 99.95381%

•2nd Qtr 2013 – 99.99944%

•3rd Qtr 2013 – 99.99955%

•YTD 2013 – 99.98446%

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• EPS Metering Protocols

• http://www.ercot.com/mktrules/nprotocols/current

–Section 10 & 11

• Settlement Metering Operating Guide (SMOG)

– http://www.ercot.com/mktrules/guides/settlement/smog

• Metering Documentation/Forms

– http://www.ercot.com/mktinfo/metering/eps/index

Reference Information


http://www.ercot.com/mktrules/nprotocols/current







http://www.ercot.com/mktrules/guides/settlement/smog







http://www.ercot.com/mktinfo/metering/eps/index








QUESTIONS?

Documents

Validation of Generation Meter Data in MV-90 xi - Itron, Inc. · Itron Utility Week - October 2013 2 AGENDA • ERCOT Overview • Metering in the ERCOT Market • EPS Meter Data