Reliability assessment of active distribution networks

The paper proposes a methodology to assess the reliability of Active Distribution Networks (ADNs) starting from a defined network infrastructure including traditional assets with the electromechanical components, modern equipment and ICT devices. The inherent risk of ADNs operation is assessed. The Pseudo Sequential Monte Carlo (PSMC) is used to simulate the reliability and the availability of lines, protection systems, automatic sectionalizing devices as well as distributed generators, communication and automation systems by adopting suitable probabilistic models of network components, loads, generation and storage. Power production from renewable intermittent energy sources is also modelled with specific probability functions. The PSMC considers, depending on the assumed regulatory framework, the probability that DERs do not follow the optimal scheduling due to technical (e.g. failures, maintenance, etc.) or economic reasons (e.g. refuse to produce caused by a too low selling price). Once a given regulatory environment is assumed, the methodology is applied to perform quantitative risk evaluation. A case study will be presented and discussed to clarify the methodology and its application to real networks. In the paper, the methodology has been used to find the reliability that the active management of the network should have in order to maintain the system reliability comparable with the current situation.