Reliability-Centered Maintenance for Overhead Transmission Lines in Composite Power System

Table 1

Scores and weighting factors of condition indicators for determining the line condition index.

Condition indicators	Descriptions	Scores	Weights
Service age	≤10	3	1
	10–20	4
	≥20	6
Insulator type	Porcelain type 1	2	3
	Silicon	2
	Porcelain type 2	4
	Glass	6
Bundle type	No	4	1
	Yes	6
Tower type	Monopole	3	2
	Lattice or H	6
Location	Plain	4	1
	Mountain	6
Weather	Dry	2	1
	Mild	4
	Humid	6
Wind	Low	2	2
	Medium	4
	High	6
Snow	Low	2	2
	Medium	4
	High	6
Dust pollution	Low	2	3
	Medium	4
	High	6
Theft rate	Low	1	4
	Medium	2
	High	4
	Extra high	6
Average number of failures per year (AFR)	Low	1	5
	Medium	2
	High	4
	Extra high	6