Woodward GCP-20 Series User Manual

Manual 37128A GCP-20 Series - Genset Control
Page 120/190 © Woodward
Phase/Vector Shift Monitoring dϕ/dt
A phase/vector shift is a sudden change in the voltage curve that is caused by a large generator load change. The
measuring circuit detects a change in a single sine wave. This sine wave is compared with a calculated mean
value from previous measurements. Monitoring encompasses all three phases. The threshold value in degrees
specifies the difference in time between the mean and the measured value in reference to a full cycle. Monitoring
can be set in various manners. The phase/vector shift watchdog may be used as an additional means for decoup-
ling from the mains. The minimum voltage that the phase shift is activated is 70 % of the rated secondary volt-
age.
Function: "Voltage cycle duration not within the permissible range" - The voltage cycle duration exceeds the
configured limit value for the phase/vector shift. The result is the power circuit breaker that disconnects from the
mains is opened and an alarm message is displayed. The prerequisite for phase/vector shift monitoring is that the
generator is operating in a mains parallel operation (the MCB and GCB are both closed).
Parameter 184
Phase shifting
monitoring ON
Phase/vector shift monitoring ON/OFF
ON................Monitoring of the mains frequency will be performed for
phase/vector shift. The subsequent parameters of this function are
displayed.
OFF..............Monitoring is disabled, and the subsequent screens of this function
are not displayed.
Parameter 185
Monitoring
----------------
Phase/vector shift monitoring single-/three / only three-phase
single-/three.During single-phase voltage phase/vector shift monitoring, tripping
occurs if the phase/vector shift exceeds the configured threshold
value (
Parameter 186) in at least one of the three phases. Note: If a
phase/vector shift occurs in one or two phases, the single-phase
threshold value (
Parameter 186) is taken into consideration; if a
phase/vector shift occurs in all three phases, the three-phase thresh-
old value (
Parameter 187) is taken into consideration. Single phase
monitoring is very sensitive and may lead to nuisance tripping if the
selected phase angle settings are too small.
only three-phase..During three-phase voltage phase/vector shift monitoring, trip-
ping occurs only if the phase/vector shift exceeds the specified thres-
hold value (
Parameter 187) in all three phases within 2 cycles.
Issuing of class F0 alarm
NOTE
If monitoring is configured to "only three-phase", only the second of the following two parameters
is visible; if monitoring is configured to "single-/threephase", both parameters are visible.
Parameter 186
Phase shift
(One phase) 00°
This screen is visible only
if monitoring is configured to
"one/three-phase".
Phase/vector shift monitoring threshold value single-phase 3 to 30 °
If the electrical angle of the mains voltage shifts more than this configured value in
any single phase, a class F0 alarm is initiated. Depending on the configured mains
decoupling procedure, the GCB, MCB, or an external CB will be opened.
Parameter 187
Phase shift
(3-phase) 00°
Phase/vector shift monitoring threshold value three-phase 3 to 30 °
If the electrical angle of the mains voltage shifts more than this configured value in
all three phases, a class F0 alarm is initiated. Depending on the configured mains
decoupling procedure, the GCB, MCB, or an external CB will be opened.

Woodward GCP-20 Series Specifications

General

Brand	Woodward
Model	GCP-20 Series
Category	Control Unit
Language	English