Woodward HighPROTEC - Page 756

Protective Elements
Setting example for generator unbalance 46G
Given generator data as follows:
Generator MVA rating (from Generator name plate or data sheet): S
Gn
= 30 MVA
Generator rated voltage (from Generator name plate or data sheet): U
Gn
= 4160 V
Generator rated current (FLA, to be calculated): I
Gn
= S
Gn
/(√3*U
Gn
) = 4163.6 A
Generator continuous current unbalance capability: 8% = Pickup = 0.08
(from Generator name plate or data sheet)
Generator unbalance fault capability: 10 s (permissible I2
2
*t) = K-value = 10
(from Generator name plate or data sheet)
Unbalance reset (cooling) time constant: τ-cool = 240 s = K-reset = 240
(from Generator name plate or data sheet)
Maximum allowed tripping time at unbalance pickup: Tmax = 600 s
(please see unbalance tripping curves)
Minimum allowed tripping time at unbalance pickup: Tmin = 0.25 s
(please see unbalance tripping curves)
All double underlined values have to be set in the menu [Protection
Para/Set(x)/Unbalance-Prot/46G[2]-I.Unbalance]
756 MCDGV4 DOK-HB-MCDGV4-2E