E. Chiodo et al., PROBABILISTIC APPROACH TO TRANSIENT STABILITY EVALUATION, IEE proceedings. Generation, transmission and distribution, 141(5), 1994, pp. 537-544
A new probabilistic approach to transient stability evaluation of elec
trical power systems is proposed. The method is relevant to planning s
tudies, where load level is a major source of uncertainty. The probabi
listic nature of both the load demand and the circuit breaker operatin
g time is taken into account for the purpose of obtaining an analytica
l evaluation of the instability probability. The approach is based upo
n the analytical computation of the probability distribution function
of the critical clearing time for stability in terms of the load deman
d distribution. It allows the expression of the instability probabilit
y as an analytical function of all the relevant system parameters. The
method is illustrated with reference to a simple (one machine - infin
ite bus) system, and the results are compared with those obtained by m
eans of statistical (Monte Carlo) simulation. The time requirement of
the two methods is comparable, but the proposed analytical approach of
fers a remarkable advantage over the Monte Carlo method for a sensitiv
ity analysis with respect to the system parameters.