Woodward HighPROTEC - Page 827

Protective Elements
Transformer: Type Two windings, 3-phase
Power rating (S
T
) 425 MVA
Rated Voltage HV (V
TH
) 145 kV
Rated Voltage LV (V
TL
) 19 kV
HV/LV connection Y0/Δ
Phase shift 1
Rated Frequency (f
N
) 60 Hz
Leakage reactance (X
T
) 0.111 (pu)
(XTG = 0.11607 (pu) = 2.04 Ω)
Power System
Base MVA (S
S
) 100 MVA
Base Voltage (V
S
) 138 kV
Positive sequence impedance during maximum generation Z
max,S1
0.000511 + j0.010033 (pu)
Negative sequence impedance during maximum generation Z
max,S2
0.001046 + j0.017206 (pu)
Positive sequence impedance during minimum generation Z
min,1
0.00105 + j0.016463 (pu)
Positive sequence impedance of the longest transmission line connected to
the unit transformer bus Z
LL1
0.01095 + j0.11546 (pu)
= 0.77 + j8.15 Ω
Zero sequence impedance of the longest transmission line connected to the
unit transformer bus Z
LL0
0.07370 + j0.37449 (pu)
Positive sequence impedance of the shortest transmission line connected to
the unit transformer bus Z
SL1
0.00546 + j0.05773 (pu)
= 0.39 + j4.08 Ω
Zero sequence impedance of the shortest transmission line connected to the
unit transformer bus Z
SL0
0.03685 + j0.18725 (pu)
Distance Protection settings for the shortest transmission line: zone 1 80%Z
SL1
Distance Protection settings for the longest transmission line: zone 2 120%Z
LL1
827 MCDGV4 DOK-HB-MCDGV4-2E