Quadrilateral Characteristic For Phase Faults; Figure 48: Impedance Reach Line Construction - GE MiCOM P40 Technical Manual

Chapter 7 - Distance Protection
Zone Type
Q Ph-Earth Offset
where k = (Z - Z ) / 3Z
ZN 0 1
Note:
Not all products feature all zones.
Note:
With default settings applied, Directional Zones 1, 2, and 4 should appear Quadrilateral.
3.2.2

QUADRILATERAL CHARACTERISTIC FOR PHASE FAULTS

Quadrilateral characteristics are available for phase fault protection. A mix of Directional Forward, Directional
Reverse, and Offset characteristics is available. Zone 1 and Zone 2 are Directional Forward. Zone 4 is Directional
Reverse. Other zones can be set independently as Offset, Directional Forward, or Directional Reverse. Each zone is
independent and is defined by an Impedance Reach Line, a Reverse Impedance Reach Line, and two resistive
blinders. The two resistive blinders (Resistive Reach Line and Reverse Resistive Reach Line) are parallel to the zone
characteristic impedance angle. The two reactance lines of each Quadrilateral exhibit a characteristic tilt. In the
phase fault characteristics the tilt of the Reverse Impedance Reach Line is preset, whilst you can choose the tilt
angle for the Impedance Reach Line.
3.2.2.1 PHASE FAULT IMPEDANCE REACH LINE
The tilt of the top line can be set independently for each zone. It is defined by a reach setting, Z, and a tilt angle, σ,
as shown in the following diagram:
V02722

Figure 48: Impedance Reach line construction

Referenced to the fault current I, the angle of tilt is equal to the setting σ. A negative angle sets a downward tilt
and a positive angle sets an upward tilt. Operation can occur when the operating signal lags the polarizing signal.
A negative angle sets a downward tilt and a positive angle sets an upward tilt.
For all V/I vectors below the Impedance Reach line, the following condition is true:
Ð (V/I - Z) £ σ
126
Impedance Reach Z
ZQ Gnd. Reach * (1 + k )
ZN
and is defined by two settings: kZN Res Comp and KZN Res Angle.
1
+jX
Z
Reverse Impedance Reach Z'
ZQ' Gnd Rev Rch * (1 + k )
ZN

V I Z

V I
+R
Reverse Resistive
Resistive Reach R
RQ Gnd Resistive RQ' Gnd Res. Rev
P446SV-TM-EN-1
P446SV
Reach R'