GE UR Series Instruction Manual page 293

8 THEORY OF OPERATION
2 2
⋅ ⋅
I 2 S 1 I _L
then =
rest
> >
4. If I _L BP and I _R
2 2 2
(
then I I _L BP
= –
rest
b) 3 TERMINAL MODE
Operating conditions are estimated with the following equation:
2
I I _L I _R1 I _R2
= + +
op
2
I is calculated with one of the following 8 equations depending on which corresponding condition is met:
rest
< <
1. If I _L BP and I _R1
4
2 2
( ( ⋅
then I -- - S 1 I _L
=
rest
3
> <
2. If I _L BP and I _R1
4
2 2
( ( ⋅ (
I = -- - S 2 I _L
rest
3
2
2
-- - σ (
2 P
+
loc
3
> >
3. If I _L BP and I _R1
4
2 2
( ( ⋅ (
I -- - S 2 I _L
=
rest
3
2
2
-- - σ (
2 P
+
loc
3
> >
I _L BP I _R1
4. If and
4
2 2
( ( ⋅ (
I = -- - S 2 I _L
rest
3
2
2
-- - σ (
2 P
+
loc
3
< >
I _L BP I _R1
5. If and
4
2 2
( ( ⋅
I -- - S 1 I _L
=
rest
3
2
2
-- - σ (
2 P
+
loc
3
< <
6. If I _L BP and I _R1
4
2 2
( ( ⋅
I -- - S 1 I _L
=
rest
3
2
2
-- - σ (
2 P
+
loc
3
GE Power Management
2
2 2 2
⋅ ⋅ ( )
2 S 2 I _R
+ – BP + 2
BP
2
2 2
) ⋅ ⋅ ( )
2 S 2 I _R BP 4 S 1
+ – +
2
<
BP and I _R2 BP
2 2 2 2
) ( ⋅ ) ( ⋅
S 1 I _R1 S 1
+ +
<
BP and I _R2 BP , then
2 2 2 2
) ) ( ⋅ )
– BP + S 1 I _R1
σ σ )
+ +
rem1 rem2
<
BP and I _R2 BP , then
2 2 2 2
) ) ( ⋅ (
BP S 2 I _R1
– +
σ σ )
+ +
rem1 rem2
>
BP I _R2 BP
and , then
2 2 2 2
) ) ( ⋅ (
– BP + S 2 I _R1
σ σ )
+ +
rem1 rem2
>
BP I _R2 BP
and , then
2 2 2 2
) ( ⋅ ( ) )
S 2 I _R1 BP
+ –
σ σ )
+ +
rem1 rem2
>
BP and I _R2 BP , then
2 2 2 2
) ( ⋅ ) ( ⋅
S 1 I _R1 S 2
+ +
σ σ )
+ +
rem1 rem2
L90 Line Differential Relay
8.2 OPERATING CONDITION CALCULATIONS
2 2 2
⋅ ⋅ ⋅ σ σ
S 1 2 P
BP + + +
loc
2 2 2
⋅ ⋅ ⋅ σ σ
BP 2 P
+ + +
loc
2
2 2
) ) -- - σ ( σ
I _R2 2 P
+ + +
loc rem1
3
2 2 2 2
( ⋅ ) ( ⋅
+ S 1 I _R2 + S 1 BP
2 2 2
) ) ( ⋅ ) (
BP S 1 I _R2 2 S 1
– + +
2 2 2
) ) ( ⋅ (
– BP + S 2 I _R2 – BP
2 2 2
( ⋅ ( ) ) (
S 2 I _R2 BP 2 S 1
+ – +
2 2 2 2
( ) ) ( ⋅
I _R2 BP S 1 BP
– +
rem
rem
σ )
+
rem2
) )
+
2 2
⋅ ) )
BP
+
2 2 2
) ) ( ⋅ ) )
+ 3 S 1 BP +
2 2
⋅ ) )
BP
+
) )
+
8
8-19