GE LPS-D, Инструкция по эксплуатации

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GE Power Management LPS-D Line Protection System 1-
9
1 PRODUCT DESCRIPTION 1.2 INTRODUCTION
1
where ZD is the angle of “maximum torque” and is equal to 65°.
The characteristic timer angle will be fixed at 115°. That is, the function will operate when the input signals are
within ±65° of each other.
If the faulted phase voltage magnitude is too low (as for a close-in Zone 1 fault), the phase directional function
will not operate. This might also occur for a remote fault when the relay is located near a strong source. There-
fore, if the phase voltage is less than the minimum threshold voltage, the positive-sequence memory voltage
from the ground Mho functions is used in place of the phase voltage to polarize the directional function.
c) RIGHT RESISTIVE BLINDER
The right resistive blinder is a two input phase angle comparator. The input signals for the comparator are:
Operate: I
φ
′
· RB 1 - V
φ
Polarize: I
φ
′
· RB 1
where:
The magnitude of RB 1 (Right Blinder for Zone 1) is the point at which the characteristic inter-
sects the R axis. The range of adjustment will be 0.1 to 500.0
Ω
in 0.1
Ω
steps.
The angle of RB 1 is be fixed based on the positive sequence line angle, the zero sequence
line angle, and the K 0 factor. The angle is:
I
φ ′
is the compensated phase current, ( I
A
- I
0
) + K
0
1
•
I
0
The characteristic timer angle will be fixed at 90°. For the Zone 1 ground function, the operate and polarizing
signals are:
1.2.5 LINE PROTECTION SCHEMES
The LPS-D provides four zones of distance protection with overcurrent backup functions. The LPS-D is a
highly flexible system: along with predefined protection schemes, it also has the ability to be programmed by
the user. The custom programmability of the LPS-D is discussed in the next section.
The LPS-D pilot protection schemes are as follows:
• Permissive Underreach Transfer Trip (PUTT)
• Permissive Overreach Transfer Trip (POTT1)
• Permissive Overreach Transfer Trip with blocking functions (POTT2)
• Blocking
• Hybrid
In addition, each of the above schemes includes up to four zones of step distance backup with individual timers
for phase and ground zones.
Phase A:
I
A
′
·
RB
1 –
V
A
I
A
′
·
RB
1
Phase B:
I
B
′
·
RB
1 –
V
B
I
B
′
·
RB
1
Phase C:
I
C
′
·
RB
1 –
V
C
I
C
′
·
RB
1
where:
I
A
′
= (
I
A
-
I
0
) +
K
0
1·
I
0
I
B
′
= ( I
B
- I
0
) + K
0
1· I
0
I
C
′
= (
I
C
-
I
0
) +
K
0
1·
I
0
K
0
1 = | K
0
1| – (ZERSEQANG – POSSEQANG)
2 POSSEQANG
⋅
K0 ZERSEQANG
⋅
+
2 K0
+
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