GE D30D00HCHF8AH6AM6BP8BX7A, Инструкция по эксплуатации

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9-8 D30 Line Distance Protection System GE Multilin
9.1 DISTANCE ELEMENTS 9 THEORY OF OPERATION
9
Distance Reach: 14
Ω
Left Blinder Reach: 5
Ω
Distance RCA: 88°
Left Blinder RCA: 88°
Polarizing Current: Zero-sequence
Non-Homogeneity Correction Angle: 3°
Directional RCA: 88°
Z0/Z1 Magnitude: 4.55
Overcurrent supervision: 3 A
Z0/Z1 Angle: –12°
Distance Comparator limit angle: 75°
Z0M/Z1 Magnitude: 0
Directional Comparator limit angle: 75°
Assume the following signals are injected to the relay:
V
A
= 64.71 V
∠
0.0° (pre-fault)
V
A
= 25.43 V
∠
–19.9°
V
B
= 80.22 V ∠ –133.5°
V
C
= 77.33 V
∠
135.7°
I
A
= 4.47 A
∠
–107.8°
I
B
= 2.92 A
∠
68.9°
I
C
= 2.93 A ∠ –51.1°
Based on the entered setting the relay calculates:
K0 = 3.58 ∠ –15.2°
K0M= 0
Z
= 14.00
Ω ∠
88°
Z
D
= 1
Ω ∠
88°
Z
R
= 9.99 Ω ∠− 2°
Z
L
= 4.99
Ω ∠
178°
For the assumed steady-state injection the relay calculates:
V
A
_1 = 58.83 V
∠
–2.1°
V
A
_1M = 64.71 V
∠
0.0°
I_0 = 1.37 A
∠
–68.2°
I
A
_2 = 1.37 A ∠ –68.1°
–V_0 = 29.18 V
∠
8.4°
(V
A
–V
B
)_1 = 93.35 V
∠
32.0°
(V
A
–V
B
)_1M = 112.08 V
∠
30.0°
I
A
–I
B
= 7.39 A ∠ –109.1°
b) MHO PHASE A TO GROUND ELEMENT (BEFORE MEMORY EXPIRES)
I
A
× Z + I_0 × K0 × Z + I
A
× K0M × Z – V
A
= 103.33 V ∠ –3.9°
V
A
_1M = 64.71 V
∠
0.0°
I
A
_2
×
Z
D
= 1.37 V
∠
19.8°
I_0
×
Z = 19.11 V
∠
19.8°
I_0 × Z
D
= 1.37 V ∠ 19.8°
• Overcurrent supervision: | 3 × I_0 | = 4.09 A > 3 A
• Mho difference angle = | –3.9° – 0° | = 3.9° < 75°
• Reactance difference angle = | –3.9° – 19.8° | = 23.7° < 75°