A Generalized Model For Quantitative Evaluation Of Reliability Indices of The National Grid System

ABSTRACT

Retbiliry indices ore considered to be remonabk md logic wuys to judge the

perfirmame of rm electric power tystem ReliabiIi~in dices which m proposed by the

IEEE are used ra evaluate the perfmmce of selected distribution.~stemo n the natlonai

grid. Ten yems of outage data (1998 - 200 7) from seven selected disi?ibwtl'on systems on

the national grid were wed as case studies in this resewch work. A generalized model is

developedf or a qsrantimive evalucrti~nof relative indices of the nationd grid ?stem. nte

development of the model stated with identffcation of the system reliabiliv indices and

estimuting the contributions ojsystem indicd to the failure rate of the selected distribution

system on the national gri'd. The computed qvstem reliability indices we used as input

paranietms for the generalized modd ReIative CADI inda is computed by simulation

using ,'KATM 7.7 which automatically generates the graph of &k reidbe CAWI against

names of feeders. The percenmge averuge relafive CAIDIs fir Ibudun, Port-Hmcowt and

Benin distribution system are 71.86%, 52.79% and 75.79% rsspectively, thus, merage

rztiabiliry levels. Rorin, Lkeja Kaduna and Kano dhkibution system have percentuge

average relative CADIS of 11.93'%, 39.76%, 440.1 7% and 41 -08% respechirely with poor

reliabiIitJl levels. With the ald of curve jtting (cj mls, hue distinct model equations were

developedfrorn which a genwalid model is formulafgd for a qarantitutive evaluati~no f

reliability indices of the natiod grid ~XgEen eralked model is a potynomia!faac~on

wbse order depends majorly on t?l~we i of indwhiaIizafrafroafn the distribution systems

ancf the number of distribution feeders.