Feasibility vs. Optimality in Distributed AC OPF - A Case Study Considering ADMM and ALADIN
For researchers and practitioners in power systems optimization, this work highlights a practical limitation of ADMM in distributed OPF, though the findings are incremental.
This paper shows that in distributed AC OPF, ADMM with large consensus-violation penalization can exhibit slow progress, and compares its performance with ALADIN on the IEEE 57 bus system.
This paper investigates the role of feasible initial guesses and large consensus-violation penalization in distributed optimization for Optimal Power Flow (OPF) problems. Specifically, we discuss the behavior of the Alternating Direction of Multipliers Method (ADMM). We show that in case of large consensus-violation penalization ADMM might exhibit slow progress. We support this observation by an analysis of the algorithmic properties of ADMM. Furthermore, we illustrate our findings considering the IEEE 57 bus system and we draw upon a comparison of ADMM and the Augmented Lagrangian Alternating Direction Inexact Newton (ALADIN) method.