  The phasor measurement unit (PMU) placement problem is revisited by taking
into account a stronger characterization of the electrical connectedness
between various buses in the grid. To facilitate this study, the placement
problem is approached from the perspective of the \emph{electrical structure}
which, unlike previous work on PMU placement, accounts for the sensitivity
between power injections and nodal phase angle differences between various
buses in the power network. The problem is formulated as a binary integer
program with the objective to minimize the number of PMUs for complete network
observability in the absence of zero injection measurements. The implication of
the proposed approach on static state estimation and fault detection algorithms
incorporating PMU measurements is analyzed. Results show a significant
improvement in the performance of estimation and detection schemes by employing
the electrical structure-based PMU placement compared to its topological
counterpart. In light of recent advances in the electrical structure of the
grid, our study provides a more realistic perspective of PMU placement in the
electric power grid.
