DC marine vessels with medium-voltage compact dc power systems are dominated by a significant amount of active loads and a finite number of generation sources. In such scenarios, the network configuration of the dc power system is expected to get dynamically altered to fulfill the required generation and load demands for the desired marine mission. Such varying network configurations make the transient responses significantly different from the conventional ac grids and the prospective dc grids. In this regard, this paper performs systematic transient studies to devise fault management strategies for the dc marine vessels. A platform supply vessel (PSV) is taken as an example of the marine vessel, due to its complex operating scenarios and wider applicability in the marine industry. Pole-to-pole short-circuit faults are considered owing to its severity. A novel current-only directional protection for the dc PSV is proposed based on the directional zonal interlocking and short-time Fourier transform. The efficacy of the proposed method is substantiated by confirming against a range of fault impedances initiated at the generator terminals, load terminals, lines, and buses of the dc PSV. All the analyses are conducted in the real-time simulation model of the dc PSV.

中文翻译：

---

直流船用电力系统：瞬态行为和故障管理方面


配备中压紧凑型直流电源系统的直流船舶主要由大量有源负载和有限数量的发电电源主导。在这种情况下，直流电力系统的网络配置预计会动态改变，以满足所需的海上任务所需的发电和负载需求。这种不同的网络配置使得瞬态响应与传统的交流电网和预期的直流电网显着不同。在这方面，本文进行了系统的瞬态研究，以设计直流船舶的故障管理策略。以平台供应船（PSV）为例，由于其作业场景复杂且在海洋行业中具有更广泛的适用性，因此以平台供应船（PSV）为例。极间短路故障因其严重性而被考虑。提出了一种基于方向分区联锁和短时傅里叶变换的新型直流PSV纯电流方向保护。通过确认直流 PSV 的发电机端子、负载端子、线路和总线处引发的一系列故障阻抗，证实了所提出方法的有效性。所有分析均在直流 PSV 的实时仿真模型中进行。