A Novel Stability Model for AC-DC Combined Simultaneous Power Flow

Abstract

Conversion of an already running AC transmission
system, with very high voltage and longer length, into a system
with the mixed operation of AC-DC can bring the benefit of
stability improvement. Of late, most of the developments in
stability analysis are simulation based. Sometimes it is difficult to
draw a generalized conclusion through simulation result. In this
case, an analytical model can be a perfect tool to analyze the fault
and get concrete decision about the future planning. In this paper
a mathematical equation is exposed which can be applied to
determine the stability in case of different types of fault.
Primarily, the stability equation is established for the fault at the
transmission line and then introducing simple logical
modification it can be applicable for the development of
analytical models of all kinds of faults, such as; Fault at the load
terminal, sustained fault at the line, fault at the line where the
generator is located. To expose the efficacy of the developed
stability model two different ways of validation process is
followed and optimistic results are found.