Multi-objective MILP model for distribution systems reliability optimization: A lightning protection system design approach

Lightning phenomenon is the main cause of power systems faults. These faults may cause momentary or permanent service interruptions, thus system reliability is inherently interdependent with lightning phenomenon. A literature review will show that state-of-the-art solutions have yet to present mathematical explicit models for the interdependency of such two phenomena. In this context, this paper presents a multi-objective mixed integer linear programing (MILP) model for distribution systems reliability optimization while considering lightning phenomenon interdependency. The presented multi-objective MILP model aims the simultaneous minimization of SAIFI and MAIFIE reliability indices and associated costs. These goals are achieved by optimizing the lightning protection system design, which includes selection and allocation of different types of grounding systems along distribution feeders, while considering simultaneously network characteristics. Validation is done using real-life 81 bus 23 kV distribution network data. Test results highlight the efficiency of the presented model in improving system reliability while reducing associated costs. The ease of implementation of design, formulation of parameters and encouraging test results indicate potential for real-life application. The multi-objective MILP model is currently used by a distribution utility as a reliability-oriented tool.