1

Reliability Improvement of

Distribution System Using Reliability Centered Maintenance

Tirapong K , Titti S

Provincial Electricity Authority (THAILAND)

www.pea.co.th

2

To presents methodology of RCM for

prediction , evaluation and optimize reliability

activities against budget limit in maintenance

process to improve distribution system

reliability and quality

High impact on

cost of electricity

High correlation with

customer satisfaction

Difficult for utilities to

address in whole picture

Distribution

Reliability

Introduction

Provincial Electricity Authority, Thailand

Maintenance

management

Preventive

maintenance

Money

efficiently

RCM(Reliability Centered Maintenance)

RCM(Reliability Centered Maintenance)

System

selection and

information

collection System

boundary

definition

Maintenance

Table

Failure Mode

and Method

Analysis

Evaluate

improvement

SAIFI,SAIDI

Effect Analysis

and Logic tree

diagram Reliability

Improvement

Opportunity

Graph

Case study

2011

2012

2003

Reliability improvement in Chiangmai municipal area

SAIFI 3.36

SAIDI 72.27

2011

2012

2013

2014

SAIFI < 2

SAIDI <20

FEEDER STUDY

CMD10

2011 INDEX

SAIFI 0.323

SAIDI 9.035

EQUIPMENT

T/L 48

T/R 19

Critical Failure Mode

8

Replace insulated cable instead bare conductor 2

install Bird Guard and insulation cover at bushing , Drop out fuse 3

Replace transformer lead conductor to insulated conductor 4

Patrol and tree trimming 1 1

Correction of Outages

RIO Curve

10

CMD10 RIO curve

11

Failure Rate

Before maintenance

After maintenance

Best case Worst case

CMD10 1.412 0.210 0.377

Failure Rate

13

References

[1] Tackett,M.H., “Evaluation alternative reliability improvement proposals using the RIP

method”,2001 Rural Electric Power, pp. D3/1-D3/8

[2] Udo,V.;Agarwal S.K.;Vojdani,A.;Harlacher,M.I., “Balancing cost and reliability: A quantitative

study at Atlantic Electric”IEEE Trans.Power System, volume12, pp.1103-1111, Mar 1997.

[3] Goswami,P.K.;Chowdhury,S.;Chowdhury,S.P.;Song,Y.H.;Das,J.K. ,“Reliability evaluation of

distribution system”,UPEC2007 Universities Power Engineering Conferen ce.,pp158-166.

[4] Rosendo,J.A.;Gomez-Exposito,A.;Tevar,G.;RodrIguez,M.;“Evaluation and improvement of supply

reliability indices for distribution networks”, 2008 Transmission and Distribution Conference and

Exposition., pp 1-6.

[5] Burke, J., “Using outage data to improve reliability”,IEEE Computer Applications in Power , vol

13.,pp 57-60 ,Apr 2000

[6] Williams,C.;McCarthy,C.;Cook,C.J., “Predicting reliability improvement ”, IEEE Power and Energy

Magazine , vol 6 ,pp 53-60 ,Mar/Apr 2008. .

[7] Brown,R.E.;Hanson,A.P.;Willis, H.L ; Luedtke,F.A.;Born, M.F., “Assessing the reliability of

distribution systems”,IEEE Computer Applications in Power , vol 14.,pp 44-49 ,Jan 2001.

[8] IEEE Guide for Electric Power Distribution Reliability Indices., IEEE Std. 1366-2012, May. 2012.

[9] H. L. Willis, G. V. Welch, and R. R. Schrieber, Aging Power Delivery Infrastructures, New York:

Marcel Dekker, 2001.