Load Impedance Limitation, With Phase Selection With Load Encroachment, Quadrilateral Characteristic Function Activated; Setting Of Minimum Operating Currents - ABB RELION 670 SERIES Applications Manual

Section 8
Impedance protection
8.9.3.8
8.9.3.9
332
£ ×
RFPG 0.8 Z
load min
EQUATION1721 V2 EN
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.
RFPPZx  
1.6 Z
load
EQUATION579 V3 EN
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.

 
 
RFPPZx 1.6 Z

load min
IECEQUATION2307 V2 EN
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).
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).

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.
é × +
2 R 1
× ¶ -
cos
ê
ë
× +
2 1
X

R1Zx
 
 
cos sin


X1Zx
1MRK 506 369-UUS -
ù
R 0
× ¶
sin
ú
û
0
X
Line distance protection REL670 2.2 ANSI
Application manual
(Equation 268)
(Equation 269)
(Equation 270)