Scalable Optimization Approach of Optimal PV Sizing Problem for Minimizing Network Loss and Inverter Loss
Shunnosuke Ikeda, Shohei Kusuhara, Akiko Takeda, Hiromitsu Ohmori
The use of photovoltaics (PV) in electric power networks has increased because of advantages such as power loss reduction, environmental friendliness, voltage profile improvement, and postponement of system upgrades. However, using PVs of an inappropriate size leads to greater power losses due to variations in PV outputs and demand loads. This paper formulates the optimal sizing PV problem (OPSP) for minimizing inverter losses and network losses. The OPSP is a large-scale and non-convex optimization that is difficult to solve. To resolve this computational issue, this paper proposes a new approach that consists of two steps. The first step is to relax the original non-convex problem into a convex one and to prove that the convexification is exact provided that over-satisfaction of the load is allowed. The second step is to decompose the original large-scale optimization into small-scale sub-problems. Moreover, the decomposed sub-problems can be computed in parallel. Numerical simulations implementing parallel processing verify the effectiveness of our approach.