Advanced Sech-Tanh Optimization Algorithm for Optimal Sizing and Placement of PV Systems and D-STATCOMs in Distribution Networks

Abstract

This paper presents an innovative approach to addressing the simultaneous integration of photovoltaic (PV) systems and distribution static compensators (D-STATCOMs) within distribution networks by employing the Sech-Tanh Optimization Algorithm (STOA). The proposed STOA method uses a discrete-continuous codification scheme to determine the optimal placement (nodes) and sizing (capacities) of PV sources and D-STATCOMs. A power flow analysis based on the successive approximations method is implemented to resolve the power flow equations, evaluating technical parameters such as voltage profiles and power injections. The problem is tackled through a master-slave optimization strategy, wherein the STOA is integrated with the power flow approach to obtain optimal solutions. The performance of this methodology is validated using 33- and 69-bus systems, showing notable improvements over traditional optimization techniques like the vortex search algorithm (VSA) and the sine-cosine algorithm (SCA). The results highlight a reduction of approximately 35.548% and 35.6801% in the objective function when applying STOA across both test systems. Furthermore, STOA exhibits a reduced computational effort in comparison to VSA and SCA, confirming its effectiveness. All numerical analyses were conducted using MATLAB 2024a.