Protective Elements
Automatic Calculations: Amplitudes, Vector Groups, and Zero Sequence Removal
The calculations performed can be done by matrix calculations. Three steps have to be completed.
1.
Adjust the amplitude according to all transformation ratios (Stepup transformer and CTs).
2.
Adjust the vector group angle by rotating the three-phase system accordingly.
3.
Remove the zero sequence current where necessary (this being valid for winding 1 and winding 2).
Re. 1.: Amplitude Adjustment:
⃗
I
W2
'
= ⃗
I
W2
⋅
k
r
k
r
=
CT
pri , W2
I
B , W2
⋅
I
b , W1
CT
pri ,W1
=
CT
pri ,W2
CT
pri ,W1
⋅
V
LL,W2
V
LL,W1
⋅
(
1
+
Tap Changer
)
Re. 2.: Vector Group Adjustment:
The vector group adjustment is calculated using the following formulas and transformation matrices:
⃗
I
W2
' '
=
[
T
Phase Shift
]
∗ ⃗
I
W2
'
[
T
Phase Shift
]
→
[
T
0,1,2...11
]
Even Connection Groups
Odd Connection Groups
T
0
=
[
1
0
0
0
1
0
0
0
1
]
T
2
=
[
0
−
1
0
0
0
−
1
−
1
0
0
]
T
4
=
[
0
0
1
1
0
0
0
1
0
]
T
6
=
[
−
1
0
0
0
−
1
0
0
0
−
1
]
T
8
=
[
0
1
0
0
0
1
1
0
0
]
T
10
=
[
0
0
−
1
−
1
0
0
0
−
1
0
]
T
1
=
1
√
3
⋅
[
1
−
1
0
0
1
−
1
−
1
0
1
]
T
3
=
1
√
3
⋅
[
0
−
1
1
1
0
−
1
−
1
1
0
]
T
5
=
1
√
3
⋅
[
−
1
0
1
1
−
1
0
0
1
−
1
]
T
7
=
1
√
3
⋅
[
−
1
1
0
0
−
1
1
1
0
−
1
]
T
9
=
1
√
3
⋅
[
0
1
−
1
−
1
0
1
1
−
1
0
]
T
11
=
1
√
3
⋅
[
1
0
−
1
−
1
1
0
0
−
1
1
]
Re. 3.: Zero sequence removal (elimination of the ground current if this can only flow through one winding at the
external asymmetrical faults and will not be transformed to the other winding).
Zero sequence removal will be calculated for the primary winding system, if the W1con value is set to YN or ZN.
A zero sequence current can only flow:
1. If the
neutral
is connected to ground; and
2. The grid on the primary side is grounded as well.
⃗
I
W1
' ' '
=⃗
I
W1
−⃗
I
0 ,
W1
630
MCDLV4
DOK-HB-MCDLV4-2E
Summary of Contents for HighPROtec MCDLV4
Page 3: ...Order Code Order Code 3 MCDLV4 DOK HB MCDLV4 2E...
Page 47: ...Installation and Connection 47 MCDLV4 DOK HB MCDLV4 2E...
Page 164: ...Input Output and LED Settings 164 MCDLV4 DOK HB MCDLV4 2E...
Page 433: ...Parameters 433 MCDLV4 DOK HB MCDLV4 2E...
Page 457: ...Device Parameters 457 MCDLV4 DOK HB MCDLV4 2E...
Page 473: ...Blockings 473 MCDLV4 DOK HB MCDLV4 2E...
Page 988: ...Protective Elements 988 MCDLV4 DOK HB MCDLV4 2E P P Q P Q P Q Q Q P S S...
Page 989: ...Protective Elements 989 MCDLV4 DOK HB MCDLV4 2E Pr Q P Q P Qr...
Page 1023: ...Protective Elements 1023 MCDLV4 DOK HB MCDLV4 2E...
