• Laurids Martedal Bergholdt Dall
  • Yi Wern Foo
4. term, Energy Engineering, Master (Master Programme)
This thesis presents a study of the elec-
tromechanical dynamics associated with the
implementation of long HVAC cables in
power transmission. Transient stability and
large-disturbance voltage stability of generic
multi-machine power systems is assessed by
RMS simulations in DIgSILENT PowerFac-
tory. The stability performance of the OHL
base case system is compared against an
equivalent cable system. Results show that
the 100 % compensated equivalent cable sys-
tem has longer CCT than the OHL base sys-
tem in most cases. Increasing the SR com-
pensation degree may improve the CCT, while
voltage stability analysis show that under-
compensation improve the V; P load-ability.
The cable system displays larger Pmax than
the OHL base system. An advantage of the
cable system is the availability of switch-able
SRs. By decreasing XSR during a large dis-
turbance, the capacitive current generated by
the cables is injected into the network to im-
pose a voltage. Case studies show that SR-
switching can improve system voltages. A
smooth voltage recovery is achieved by se-
quentially switching the buses measuring the
lowest voltages. Further work is required in
order to generalize and quantify the proper-
ties of SR-switching.
SpecialisationElectric Power Systems and High Voltage Engineering
Publication date1 Jun 2016
ID: 234544728