Areva MiCOM P441, Technical Manual

Page: 274 / 636

P44x/EN AP/E33 Application Notes
Page 100/220 MiCOM P441/P442 & P444
3.1.5 Zone 1 Phase Reach Settings
Required Zone 1 reach is to be 80% of the line impedance between Green Valley and Blue
River substations.
Required Zone 1 reach = 0.8 x 100 x 0.484 / 79.4
°
x 0.12
Z1 = 4.64 / 79.4
° Ω
secondary.
Z2 = 100 x 0.484 / 79.4° + 50% x 60 x 0.484 / 79.4°
The Line Angle = 80
°
.
Therefore actual Zone 1 reach, Z1 = 4.64 / 80
° Ω
secondary.
3.1.6 Zone 2 Phase Reach Settings
Required Zone 2 impedance =
(Green Valley-Blue River) line imp 50% (Blue River-Rocky Bay) line impedance
Z2 = (100+30) x 0.484 / 79.4
°
x 0.12
= 7.56 / 79.4
° Ω
secondary.
The Line Angle = 80
°
.
Actual Zone 2 reach setting = 7.56 / 80
° Ω
secondary
3.1.7 Zone 3 Phase Reach Settings
Required Zone 3 forward reach =
(Green Valley-Blue River + Blue River-Rocky Bay) x 1.2
= (100+60) x 1.2 x 0.484 / 79.4
°
x 0.12
Z3 = 11.15 / 79.4
°
ohms secondary
Actual Zone 3 forward reach setting = 11.16 / 80
°
ohms secondary
3.1.8 Zone 4 Reverse Settings with no Weak Infeed Logic Selected
Required Zone 4 reverse reach impedance = Typically 10% Zone 1 reach
= 0.1 x 4.64 / 79.4
°
Z4 = 0.464 / 79.4
°
Actual Zone 4 reverse reach setting = 0.46 / 80
°
ohms secondary
3.1.9 Zone 4 Reverse Settings with Weak Infeed Logic Selected
Where zone 4 is used to provide reverse directional decisions for Blocking or Permissive
Overreach schemes, zone 4 must reach further behind the relay than zone 2 for the remote
relay. This can be achieved by setting: Z4
≥
((Remote zone 2 reach) x 120%) minus the
protected line impedance:
Remote Zone 2 reach =
(Blue River-Green Valley) line imp 50% (Green Valley-Tiger Bay) line impedance
= (100+40) x 0.484 / 79.4
°
x 0.12
= 8.13 / 79.4
° Ω
secondary.
Z4
≥
((8.13 / 79.4
°
) x 120%) - (5.81 / 79.4
°
)
= 3.95 / 79.4
°
Minimum zone 4 reverse reach setting = 3.96 / 80
°
ohms secondary