ABB Relion 670 series - Load Impedance Limitation, with Phase Selection with Load Encroachment, Quadrilateral Characteristic Function Activated; Setting of Minimum Operating Currents

min
2 1 0
0.8 cos sin
2 1 0
load
R R
RFPG Z
X X
× +
£ × × ¶ - × ¶
× +
é ù
ê ú
ë û
EQUATION1721 V2 EN (Equation 268)
Where:
∂ is a maximum load-impedance angle, related to the maximum load power.
To avoid load encroachment for the phase-to-phase measuring elements, the set resistive
reach of any distance protection zone must be less than 160% of the minimum load
impedance.
load
1.6 ZRFPPZx


EQUATION579 V3 EN (Equation 269)
Equation 147 is applicable only when the loop characteristic angle for the phase-to-phase
faults is more than three times as large as the maximum expected load-impedance angle.
More accurate calculations are necessary according to equation 148.
load min
R1Zx
RFPPZx 1.6 Z cos sin
X1Zx

   







IECEQUATION2307 V2 EN (Equation 270)
All this is applicable for all measuring zones when no Power swing detection function
ZMRPSB (78) is activated in the IED. Use an additional safety margin of approximately
20% in cases when a ZMRPSB (78) function is activated in the IED, refer to the
description of Power swing detection function ZMRPSB (78).
8.9.3.8 Load impedance limitation, with Phase selection with load encroachment,
quadrilateral characteristic function activated
The parameters for shaping of the load encroachment characteristic are found in the
description of Phase selection with load encroachment, quadrilateral characteristic
function (FRPSPDIS ,21).
8.9.3.9 Setting of minimum operating currents
The operation of Distance protection zone, quadrilateral characteristic (ZMQPDIS, 21)
can be blocked if the magnitude of the currents is below the set value of the parameter
IMinPUPP and IMinPUPG.
Section 8 1MRK 506 369-UUS -
Impedance protection
332 Line distance protection REL670 2.2 ANSI
Application manual