GE D30D00HCHF8AH6AM6BP8BX7A, Instruction Manual

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9-10 D30 Line Distance Protection System GE Multilin
9.1 DISTANCE ELEMENTS 9 THEORY OF OPERATION
9
I_0
×
Z
D
= 1.37 V
∠
19.8°
I
A
×
Z
R
+ I_0
×
K0
×
Z
R
+ I
G
×
K0M
×
Z
R
– V
A
= 87.6 V
∠
–109.2°
I
A
×
Z
R
+ I_0
×
K0
×
Z
R
= 91.5 V
∠
–93.0°
I
A
×
Z
L
+ I_0
×
K0
×
Z
L
+ I
G
×
K0M
×
Z
L
– V
A
= 57.0 V
∠
108.7°
I
A
×
Z
L
+ I_0
×
K0
×
Z
L
= 45.8 V
∠
82.9°
• Overcurrent supervision: | 3
×
I_0 | = 4.09 A
>
3 A
• Reactance difference angle = | –3.9° – 24.8° | = 28.7°
<
75°
• Zero-sequence difference angle = | –19.8° – 0.0° | = 19.8°
<
75°
• Negative-sequence directional difference angle = | –19.8° – 0.0° | = 19.8°
<
75°
• Right blinder difference angle = | –93.0° – (–109.2°) | = 16.2°
<
90°
• Left blinder difference angle = | 82.9° – 108.7° | = 25.8°
<
90°
• Fault-type comparator difference angle = | 19.8° – 19.8° | = 0.0°
<
50°
All six comparators and the overcurrent supervision are satisfied.
The Quad Phase A ground element will operate for this fault.