Figure 149: Phase Selector Timing For Power Swing Condition - GE MiCOM P40 Agile Technical Manual

P543i/P545i
Configuring Settings-Free Power Swing Detection
The power swing detection based on superimposed current requires no system study. You just need to decide
whether a zone should be blocked or allowed to trip if a power swing is detected. You do this zone by zone using
the zone specific settings. For example the zone 1 setting is Zone 1 Ph. PSB. The available options are Blocking,
Allow Trip, or Delayed Unblock.
3.1.1.1 TIMING OF THE PHASE SELECTOR SIGNALS
Start of
power swing
i (t)
PH1
PH2
: D i exceeds threshold 1 (5%In), so PH1 and PH2 go high
t
1
t : Threshold 2 invoked. PH2 goes low on account of threshold being increased . PH1 remains high,
2
because there continues to be a D i
: PH1 goes low as power swing has diminished and D i goes below threshold 1
t
3
V02769

Figure 149: Phase selector timing for power swing condition

P54x1i-TM-EN-1
3 cycles
t t
1 2
Chapter 10 - Power Swing Functions
End of
power swing
t
3
273