Protective Elements
Working Principle Synchrocheck (System-to-System)
(Please refer to the block diagram on next page.)
The synchrocheck function for two systems is very similar to the synchrocheck function for generator-to-system
except there is no need to take the breaker closing time into account. The synchrocheck element measures the
three phase-to-neutral voltages »
VL1«, »VL2«, and »VL3« or the three phase-to-phase voltages »VL1-L2«, »VL2-
L3«, and »VL3-L1« of the station voltage bus bar. The line voltage Vx is measured by the fourth voltage input. If all
synchronous conditions are fulfilled (i. e.:
ΔV [VoltageDiff],
ΔF [SlipFrequency],
and
Δφ [AngleDiff]) are within the
limits, a signal will be issued that both systems are synchronous.
437
MRU4
DOK-HB-MRU4-2E