All Electric Ships Integrated Power Systems: Dependable Design based on Fault Tree Analysis and Dynamic Modeling

The all-electric ship concept is becoming a standard for ships with large power requirements. At present, the design of the onboard power system [i.e., the integrated power system (IPS)] is done through a well-proven process. This process relies on historical data and trial-and-error procedures developed in nearly 30 years of design experience to address the ship’s complexity. Nowadays, the evolution in IPSs is pushed forward by the introduction of more demanding requirements, which can be complied with only by using new power system architectures and introducing onboard innovative subsystems. However, introducing innovation by means of a design process defined on the basis of past experience is inefficient. Thus, new design paradigms are needed. In this regard, concepts and tools from other technical areas can be used to achieve a “dependable design process” able to ease the introduction of innovation in ships’ IPSs. In this paper, after a brief presentation of the conventional process and the actual drivers pushing toward its revolution, the dependable design process is proposed. The latter integrates both dependability enforcing techniques and dynamic power system modeling. Insights about the process integration in the overall ship design process are given, while an application example is used to show the effectiveness of the proposed approach.