SYSTEM LOSS SEGREGATION PROCESS

OBJECTIVE

TO BE ABLE TO MAKE US AWARE OF THE DETAILED PROCEDURE OF SYSTEM LOSS SEGREGATION FROM GATHERING OF SYSTEM DATA TO THE ACTUAL SEGREGATION OF LOSSES.

OUTLINE

I. DATA GATHERINGII. DATA ORGANIZATION / ENCODINGIII. SANITY CHECK PROCESSIV. SYSTEM MODELLINGV. LOAD FLOW SIMULATIONSVI. SEGREGATION OF LOSSES

I. DATA GATHERING

We try to capture as accurate as possible all the information and physical characteristics of the system from the Sub-Transmission Line, Power Transformers down to the individual consumers.

Typical Distribution System

a) Sub-transmission Linesb) Substation Power

Transformersc) Primary Distribution Linesd) Distribution Transformerse) Secondary Distribution

Linesf) Service Dropsg) Voltage Regulatorsh) Capacitorsi) Reactorsj) Other electrical equipment

Substation Transformer

Residential

Sub-Transmission Lines

Primary Distribution Lines (Laterals)

Distribution Transformer

Commercial Industrial

Misc Loads

Secondary Distribution Lines

Service Drop

Primary Distribution Lines (Main Feeder)

BUS ID Assignment

Equipment installedLateral LinesChanges of ConfigurationConductor sizeUnderbuilt (pole to pole)Open Secondary (pole to pole)Service drop

Where can you find the system data ?

In the fieldIn the office (billing and engineering)

What are the requirements of data gathering activities?

Qualified and dedicated technical personnel.Tools /instrument such as measuring wheel or tape, compass, GPS unit, digital camera, binocular, calculator, communication units such as mobile phone or two-way radio, visible markers, and so on.

What are the requirements of data gathering activities?

Gathered data must be placed in a worksheet, staking sheet, map or diagram (it should be understandable for all the members of the team).Logistics support such as vehicle, computers, and dedicated area in the engineering office.

Lessons learned from data gathering in the FIELD

Pilferage reduction (by-pass of metering facilities and fraud to authority)Technical loss reduction (broken neutral, unloaded DTs, no neutral wire, stop meter, and so on)System corrections due to poor workmanship ( octopus tap, non-observance of basic clearances, material substitution, and so on) Plan maintenance activities (clearing program, pole maintenance program, replacement of damage insulators, and so on)Familiarity on the physical location of vital protection/equipment of the systemLocation awareness

Lessons learned from data gathering in the OFFICE

Check and balance of billing records with engineering records Correction of office data versus field dataUn-billed customer/no customer recordRetrieval and safe-keeping of technical data of equipment/materials.

Impact of Data Gathering in Improvement of System Operation

Reduction of System Loss (though not readily quantifiable)Improved service reliability

II. DATA ORGANIZATION and ENCODING

In-charge must be familiar with the ff.:Microsoft Excel program (expert)ERC Guidelines and prescribed instructions in filling-up the ERC-DSL Form.NEA Standard CodingSpecifications of 13.2 kV distribution systemRecommend to acquire AM/FM software

ERC Data Requirements TemplatesERC-DSL-01 Administrative Load DataERC-DSL-02 Customer DataERC-DSL-03 Billing Cycle DataERC-DSL-04 Customer Energy Consumption DataERC-DSL-05 Load Curve DataERC-DSL-06 Bus DataERC-DSL-07 Subtransmission Line Data - OverheadERC-DSL-08 Subtransmission Line Data - Underground/Submarine ERC-DSL-09 Substation Power Transformer Data - Two WindingERC-DSL-10 Substation Power Transformer Data - Three WindingERC-DSL-11 Primary Distribution Line Data - OverheadERC-DSL-12 Primary Distribution Line Data - Underground CableERC-DSL-13 Primary Customer Service Drop Data - OverheadERC-DSL-14 Primary Customer Service Drop Data - Underground ERC-DSL-15 Distribution Transformer DataERC-DSL-16 Secondary Distribution Line DataERC-DSL-17 Secondary Customer Service Drop DataERC-DSL-18 Voltage Regulator DataERC-DSL-19 Shunt Capacitor DataERC-DSL-20 Shunt Inductor DataERC-DSL-21 Series Inductor DataERC-DSL-22 Energy Sales DataERC-DSL-23 Other Technical Data

Lessons Learned in Data Organization / Encoding

Accessibility of information needed;Analysis of system derived easily;Technology is the tool to fast-track the plan

BENEFITS OF DATA ORGANIZATION SYSTEM OPERATION

Development of Distribution System Asset Database

III. SANITY CHECK PROCESS

Checks for the ff: (Sanity Check Program )ConnectivityPhasingRadiality

OthersMultiplicity Program – uniqueness checkerComparator Program – 1 to 1 CheckerFROM-TO Changer Program – Root Checker

Sanity Check 1.2.6

Typical Distribution System

Substation Transformer

Residential

Sub-Transmission Lines

Primary Distribution Lines (Laterals)

Distribution Transformer

Commercial Industrial

Misc Loads

Secondary Distribution Lines

Service Drop

Primary Distribution Lines (Main Feeder)

Check for:1. Connectivity2. Phasing3. Radiality

Interpretation of Results

A B C D E F G H I J K L M NPL_Bus0001 PL_Bus0002 BN 1 1 1 0 24 1 0 1 0 1 0PL_Bus0001 PL_Bus0007 BACN 0 1 1 0 2134 1 0 1 0 1 0PL_Bus0007 PL_Bus0009 BACN 0 2 1 2134 2134 1 1 1 0 1 0PL_Bus0009 PL_Bus0010 BACN 0 3 1 2134 2134 1 1 1 0 1 0PL_Bus0009 PL_Bus0019 CABN 0 3 1 2134 3124 1 1 1 0 1 0PL_Bus0009 PL_Bus0030 BACN 0 3 1 2134 2134 1 1 1 0 1 0PL_Bus0010 PL_Bus0011 BACN 1 4 1 2134 2134 1 1 1 0 1 0

From Bus ID

To Bus ID

Phasing

Terminal Branch

Layer

TreeNumber

Phasing of From_Bus

Phasing of To_Bus

PhasingCheck

Branch Type of From_Bus

Branch Type of To_Bus

Branch Type Check

Radiality Check 1

Radiality Check 2

Interpretation of Results

Interpretation of Results

Interpretation of Results

Interpretation of Results

Interpretation of Results

Interpretation of Results

Interpretation of Results

Interpretation of Results

Interpretation of Results

IV. MODELING PROCESS

Checking of data assignment based on prescribed instructions (Engineering Attributes Programs)Typical values assignmentField data checker

Engineering Attributes Program

V. LOAD FLOW SIMULATIONS / SEGREGATION OF LOSSES

Load flow simulation of system using three-phase unbalanced load flow algorithm.NOTE :

Segregation of System Loss accuracy is totally dependent on the integrity of the network data gathered.

Uses of Load Flow Study

Sensitivity Analysis with Load Flow Study

Analysis of Existing Conditions

Analysis for Correcting PQ Problems

Expansion Planning

Contingency Analysis

System Loss Analysis

Sensitivity Analysis with Load Flow Study1) Take any line, transformer or

generator out of service.2) Add, reduce or remove load to any or

all buses.3) Add new transmission or distribution

lines.4) Increase conductor size on T&D lines.5) Change bus voltages6) Change transformer taps.7) Increase or decrease transformer

size.

ANALYSIS OF EXISTING CONDITIONS

Check for voltage violationsPGC: 0.95 – 1.05 p.u. (For Transmission)PDC: 0.90 – 1.10 p.u (For Distribution)*

*Recommended 0.95 – 1.05 p.u.

Check for branch power flow violationsTransformer OverloadsLine Overloads

Check for system lossesCaps on Segregated DSL

ANALYSIS FOR CORRECTING PQ PROBLEMS

• Voltage adjustment by utility at delivery pointTransformer tap changing

Available TapsAt Primary SideAt Secondary SideBoth Sides

Typical Taps Tap 1: +5%Tap 2: +2.5%Tap 3: 0% (Rated Voltage)Tap 4: -2.5%Tap 5: -5%

Capacitor compensationCompensate for Peak LoadingCheck overvoltages during Off-PeakOptimize Capacitor Plan

• System configuration improvement

EXPANSION PLANNING

New substation constructionSubstation capacity expansionNew feeder segment construction / extensionAddition of parallel feeder segmentReconducting of existing feeder segment/ circuit Circuit conversion to higher voltageAddition of Generating units

CONTINGENCY ANALYSIS

Reliability analysis of the Sub-transmission System and Distribution System

SYSTEM LOSS ANALYSIS

Segregation of System Losses

DSL SEGREGATOR 2.0