Figure - Toshiba GR200 Series Instruction Manual

Connection point in PLC logic
◆
DIFL (Function ID: 41001)
Element ID
830001EBB0
810002EBB1
820000EBB2
830003EBB3
800000EBB0
810000EBB6
820000EBB7
8F0000EBB4
800000EBB5
840002EBB0
800000EBB8
810000EBB9
820000EBBA
800000EBBB
810000EBBC
820000EBBD
800000EBBE
810000EBBF
820000EBC0
800000EBC1
810000EBC2
820000EBC3
Zero-sequence current differential protection (DIFGL)
Zero-sequence current differential protection (DIFGL) function is provided to enhance
sensitivity upon occurrence of an earth fault having high impedance. To perform sensitive
protection in the DIFGL function, residual current (Ie) is applied. Note that the residual
current is introduced by the CT for the residual circuit.
Differential protection characteristics (DIFGL)
2.3.1
Ir-Id plane for DIFGL function
(i)
Figure 2.3-1 shows the percentage restraining characteristic in the DIFGL element.
Differential current (I d0 ) denotes a vector summation of the residual currents in all terminals;
restraining current (I r0 ) denotes a scalar summation of the residual currents in all terminals.
The I d0 and I r0 currents are also derived using Equations (2.3-1) and (2.3-2):
Name Description
ADD.DIFLFS Add File-safe condition
DIFL-CTF_BLOCK DIF-L ctf detect block
DIFL-RDIF_BLOCK Remote differential detect block
DIFL-SV_BLOCK Differential current monitoring block
DIFL-TP_BLOCK DIF-L trip block
DIFL_3PTP Trip signal by DIF-L protection operation (3-phase)
DIFL_ARCBLOCK Autoreclose block signal by DIF-L protection operation
DIFL_BLOCK Block all the above four
DIFL_INST_OP DIF-L protection instant operation command
EXTERNAL_DIFL-CTF External CTF condition
R1.DIFL-A_OP Receiving signal from Remote Terminal 1 (phase-A)
R1.DIFL-B_OP Receiving signal from Remote Terminal 1 (phase-B)
R1.DIFL-C_OP Receiving signal from Remote Terminal 1 (phase-C)
R2.DIFL-A_OP Receiving signal from Remote Terminal 2 (phase-A)
R2.DIFL-B_OP Receiving signal from Remote Terminal 2 (phase-B)
R2.DIFL-C_OP Receiving signal from Remote Terminal 2 (phase-C)
R3.DIFL-A_OP Receiving signal from Remote Terminal 3 (phase-A)
R3.DIFL-B_OP Receiving signal from Remote Terminal 3 (phase-B)
R3.DIFL-C_OP Receiving signal from Remote Terminal 3 (phase-C)
R4.DIFL-A_OP Receiving signal from Remote Terminal 4 (phase-A)
R4.DIFL-B_OP Receiving signal from Remote Terminal 4 (phase-B)
R4.DIFL-C_OP Receiving signal from Remote Terminal 4 (phase-C)
= | I1
I
d0
- 41 -
|
+ I2 + I3
0 0 0
6F2S1914 (0.49)
(2.3-1)
GRL200 (Soft 033 & 037)