  Power systems incrementally and continuously upgrade their components, such
as transmission lines, reactive capacitors, or generating units.
Decision-making tools often support the selection of the best set of components
to upgrade. Optimization models are often used to support decision making at a
given point in time. After certain time intervals, re-optimization is performed
to find new components to add. In this paper, we propose a decision-making
framework for incrementally updating power system components. This is an
alternative approach to the classical sequential re-optimization decision
making for an investment problem with modeled budget constraints. Our approach
provides a priority list as a solution with a list of new components to
upgrade. We show that i) our framework is consistent with the evolution of
power system upgrades, and ii) in particular circumstances, both frameworks
provide the same solution if the problem satisfies submodularity property. We
have selected the problem of phasor measurement unit localization and compared
the solution with the classical sequential re-optimization framework. For this
particular problem, we show that the two approaches provide close results,
while only our proposed algorithm is applicable in practice. The cases of 14
and 118 IEEE buses are used to illustrate the proposed methodology.
