Probabilistic security analysis of shipboard DC zonal electrical distribution systems

Due to significant gains in terms of survivability, weight, manning, and cost obtained from DC zonal electrical distribution systems (DC ZEDS), various practical applications of DC ZEDS to shipboard electric power systems are expected in the foreseeing future. How to ensure whether shipboard DC ZEDS under different power outage events is secure becomes important for real-time operation and planning of the system. This paper proposes a probabilistic AC/DC power flow based security analysis method. The variations in power generation and load are considered in the analysis by using probabilistic load flow computations. Then, a security index that incorporates the stochastic characteristics of contingency and transmission line priority and electrical load importance considerations is proposed for the security analysis. A navy surface combatant shipboard power system with AC/DC network is used to validate and ensure the performance of the proposed method.