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<< Click to Display Table of Contents >> Navigation: Components and parameters > Elements > Shunt reactor |
A shunt reactance coil can be given in mH (per phase) or Mvar/kvar (three-phase). The button Appearance is used to switch between the two different input possibilities and to convert between them.
PARAMETERS
Shunt reactor
Parameter |
Default |
Unit |
Description |
Name |
|
|
Name |
Unom |
1) |
kV |
Nominal voltage |
Q |
0 |
Mvar |
Reactive power |
L 2) |
0 |
mH |
Induction |
Profile |
Default |
|
Name of the coil power profile |
1) Unom of the node
2) L is converted from Q and vice versa
Connection
Parameter |
Default |
Unit |
Description |
Star point earthing |
no |
yes/no |
Indicates whether the star point is earthed |
Re |
0 |
Ohm |
Earthing resistance with earthed star point |
Xe |
0 |
Ohm |
Earthing reactance with earthed star point |
External node |
|
|
Node with neutral earth connection |
External node
Possibility to connect the neutral point of the reactance coil to the earthing electrode at another node.
Voltage control
Parameter |
Default |
Unit |
Description |
Voltage control on |
off |
on/off |
Indicates whether the voltage control has been switched on or off |
Uon |
0 |
kV |
Voltage above which the shunt reactor switches off |
Uoff |
0 |
kV |
Voltage under which the shunt reactor switches on |
Uon > Uoff
Reliability
Parameter |
Default |
Unit |
Description |
Failure frequency |
0 |
per year |
Mean number of occurrences that the coil fails (short circuit) |
Repair duration |
0 |
minutes |
Mean duration of repair or replacement |
Maintenance frequency |
0 |
per year |
Mean number of occurrences that the coil is in maintenance |
Maintenance duration |
0 |
minutes |
Mean duration of maintenance |
maint. cut-off duration |
0 |
minutes |
Mean duration of cancellation of maintenance in case of emergency |
MODELLING
Load flow and fault analysis
The shunt reactor is modelled with three coils in Wye connection. The rating is given for one coil between phase and neutral. The reactive power is always the three-phase power.
For the load flow and the sequential fault analysis, a shunt reactor is represented as a load with:
Pload = 0
and
Qload = - Qreactor
or
Qload = - Unom,reactor2 × ω C
where:
Qload |
constant X = 100 % |
Qcapacitor |
supplied reactive power at Unom of the shunt reactor |
Unom,capacitor |
nominal phase to phase voltage of the shunt reactor |
ω |
Angular frequency ( 2πf ) |
The shunt reactor is modelled as a constant negative impedance load. This means that the shunt reactor supplies the nominal reactive power at nominal voltage only. The supplied reactive power depends quadratically on the voltage.
IEC 60909
Shunt reactor are not taken into consideration in IEC 60909 calculations.