Power Swing Detect (Ansi 68) - GE D30 Instruction Manual

CHAPTER 5: SETTINGS
Ground directional supervision
A dual (zero-sequence and negative-sequence) memory-polarized directional supervision applied to the ground distance
protection elements has been shown to give good directional integrity. However, a reverse double-line-to-ground fault can
lead to bad operation of the ground element in a sound phase if the zone reach setting is increased to cover high
resistance faults.
Ground distance zones 2 and higher use an additional ground directional supervision to enhance directional integrity. The
element's directional characteristic angle is used as a maximum torque angle together with a 90° limit angle.
The supervision is biased toward operation in order to avoid compromising the sensitivity of ground distance elements at
low signal levels. Otherwise, the reverse fault condition that generates concern has high polarizing levels so that a correct
reverse fault decision can be reliably made.

5.7.5 Power swing detect (ANSI 68)

SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  POWER SWING DETECT
 POWER SWING
 DETECT
D30 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 5-92: Ground directional supervision logic
POWER SWING

FUNCTION: Disabled
POWER SWING

SOURCE: SRC 1
POWER SWING

SHAPE: Mho Shape
POWER SWING

MODE: Two Step
POWER SWING

SUPV: 0.600 pu
POWER SW I2 SUPV ENAB:

Off
POWER SWING

I2 SUPV: 0.2 pu
POWER SWING FWD

REACH: 50.00 Ω
POWER SWING QUAD FWD

REACH MID: 60.00 Ω
POWER SWING QUAD FWD

REACH OUT: 70.00 Ω
POWER SWING FWD

RCA: 75°
POWER SWING REV

REACH: 50.00 Ω
GROUPED ELEMENTS
Range: Disabled, Enabled
Range: SRC 1, SRC 2
Range: Mho Shape, Quad Shape
Range: Two Step, Three Step
Range: 0.050 to 30.000 pu in steps of 0.001
Range: FlexLogic operand
Range: 0.050 to 30.000 pu in steps of 0.001
Range: 0.10 to 500.00 ohms in steps of 0.01
Range: 0.10 to 500.00 ohms in steps of 0.01
Range: 0.10 to 500.00 ohms in steps of 0.01
Range: 40 to 90° in steps of 1
Range: 0.10 to 500.00 ohms in steps of 0.01
5
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