A Novel Wide-Area Backup Protection Based on Fault Component Current Distribution and Improved Evidence Theory

Table 2

Assignment results of BPA values of distance protection of 𝐿₁.

Suspicious faulty line	Action state
	①	②	③	④
𝐿1	𝑥=1, 𝑦2=𝑦3=0	𝑥=1, 𝑦2=𝑦3=0	𝑥=𝑦2=𝑦3=0	𝑥=𝑦2=𝑦3=0
𝐿2 and 𝐿3	𝑥=0, 𝑦2=𝑙3/𝑙2+𝑙3,; 𝑦3=𝑙2/𝑙2+𝑙3	𝑥=0, 𝑦2=𝑙3/𝑙2+𝑙3,; 𝑦3=𝑙2/𝑙2+𝑙3	𝑥=0, 𝑦2=𝑦3=0.5	𝑥=𝑦2=𝑦3=0
𝐿2	𝑥=0, 𝑦2=1, 𝑦3=0	𝑥=0, 𝑦2=1, 𝑦3=0	𝑥=0, 𝑦2=1, 𝑦3=0	𝑥=𝑦2=𝑦3=0
𝐿3	𝑥=0, 𝑦2=0, 𝑦3=1	𝑥=0, 𝑦2=0, 𝑦3=1	𝑥=0, 𝑦2=0, 𝑦3=1	𝑥=𝑦2=𝑦3=0
𝐿1 and 𝐿2	𝑥=1, 𝑦2=𝑦3=0	𝑥=1−𝑃𝐿1_1/𝑃𝐿1_2−𝑃𝐿1_1,; 𝑦2=𝑃𝐿1_2−1/𝑃𝐿1_2−𝑃𝐿1_1, 𝑦3=0	𝑥=0, 𝑦2=1, 𝑦3=0	𝑥=𝑦2=𝑦3=0
𝐿1 and 𝐿3	𝑥=1, 𝑦2=𝑦3=0	𝑥=1−𝑃𝐿1_1/𝑃𝐿1_2−𝑃𝐿1_1,; 𝑦2=0, 𝑦3=𝑃𝐿1_2−1/𝑃𝐿1_2−𝑃𝐿1_1	𝑥=0, 𝑦2=0, 𝑦3=1	𝑥=𝑦2=𝑦3=0