Maximizing technical and economical benefits of distribution systems by optimal allocation and hourly scheduling of capacitors and distributed energy resources

Technical and economic benefits of installing distributed energy resources (DERs) and capacitor banks (C-Bs) can be maximized by optimal allocation of them. The aim of this paper is to enrich technical benefits such as voltage profile, system losses and reliability and also to increase economic benefits by maximizing the savings of energy losses and decreasing the cost of energy not supplied. The work in this paper is divided into three stages; (i) optimal placement of DERs, (ii) optimal placement of C-Bs and (iii) optimal placement of C-Bs with the existence of installed optimal DERs. The daily load variations have been considered to optimally schedule fixed and switched C-Bs. Aim of this work is formulated as a maximum objective function and is solved by a modern optimization algorithm called sine cosine algorithm (SCA). The proposed SCA method is tested on standard IEEE 33 and 69-bus radial distribution systems. Results show that the developed SCA is able to maximize the annual savings and hybrid integration of DGs and C-Bs to distribution networks is preferable than integrating one of them alone. Also, superiority of the proposed algorithm is verified by comparing its results with other optimization methods and by using a non-parametric Wilcoxon statistical test. © 2019, © 2019 Engineers Australia.