David P. Chassin, Eudoxys Sciences LLC
April 2026
Citation: D.P. Chassin, "Fast optimal capacity expansion (OCE) using softened relaxed optimal powerflow", April 2026, https://github.com/eudoxys/fast_oce.
This notebook presents a method for solving the problem of expanding real and reactive power resources on an electric network as a relaxation of the optimal power flow problem with softened constraints on loads (i.e., addition of static VAR devices), generation capacities (i.e., generator and substation capacity expansion), and line flows (i.e., transmission line capacity expansion).
The relaxations enable the use of convex optimization solvers as illustrated
here using cvxpy. These are discussed in the
first section. The softening of constraints converts the problem from a
canonical optimal powerflow problem to an optimal capacity expansion problem,
which is discussed in the second section.
The method does not support adding generators to PQ busses nor does it support adding new transmission lines or transformers where none are already present as one might find in an optimal sizing and placement problem.
./notebook.sh