Determination Of The Residual Voltage Vg For Various Connection Types; Calculation From The Three Phase-To-Ground Voltages - Woodward HighPROTEC MCDLV4 Manual Del Usuario

2 Hardware

2.6.4 Determination of the Residual Voltage VG for Various Connection Types

2.6.4 Determination of the Residual Voltage VG for Various Connection
Types
The residual voltage can be calculated either from the three phase-to-ground voltages, or
it can be directly measured at the neutral terminal (e. g. of the generator) or over the
broken delta.
The method is selected (via setting parameter »VG[x] . Fuente VG«) for each instance of
the residual voltage protection »VG[x]«
2.6.4.1

Calculation from the Three Phase-to-Ground Voltages

L1 L2 L3
V̲ L 12
V̲ L 23
V̲ L 31
The residual voltage is calculated from the three phase-to-ground voltages with the
following setting:
• »VG[x] . Fuente VG« = «calculado»
The residual voltage can be calculated only if the phase-to-ground voltages (star
connection) are connected to the measuring inputs of the device.
If the phase-to-phase voltages (delta connection) are measured instead of the phase-to-
ground voltages (star connection) it is not possible to calculate the residual voltage.
134
Elemento de Ejemplo
20000 V
100 V
3
3
V̲ L 1'
V̲ L 1
V̲ L 2
V̲ L 3
¡INDICACIÓN!
separately.
Par. cam./VT
Nombre
VT pri
VT sec
VT con
TVT pri
TVT sec
Sinc V
V̲ L 31'
V̲ L 12'
V̲ L 23'
V̲ L 2' V̲ L 3'
MCDLV4
Valor Unidad
20000 V
100 V
Fase a masa
20000
V
100 V
L12
X?.
L1
1
2
L2
3
4
L3
5
N
6
7
8
MCDLV4-3.7-ES-MAN
VL1/VL12
VL2/VL23
VL3/VL31
VG