Cost considerations play a very important role in power system operation an
d planning. In traditional reliability analysis, these costs have rarely be
en taken into account, primarily because of the lack of suitable mathematic
al models. The aim of this paper is to introduce one set of such models, To
model the economic aspects of component on system reliability, cost rates
are introduced to the states and cost impulses to the transitions of the Ma
rkov chain. Then, the cost related reliability measures are defined and the
ir relationship td the traditional reliability indices is illustrated, A br
ief discussion on the solution procedures for the modified Markov chain is
offered followed by an illustrative numerical example.