中压船舶电网单相接地故障分析与仿真

Analysis and Simulation of Single-phase Grounding Fault in Marine Medium Voltage Power Grid

单相接地故障是中压船舶电力系统中的频发故障,容易发展成严重的短路故障而威胁系统运行安全。为充分了解该类故障,结合实际中压船电系统给出了零序等效网络,分析了系统中出现单相接地故障时零序电流的分布情况,并以表达式和矢量图的形式阐明了故障线路与非故障线路上零序电流的幅值与相位特征。在MATLAB中建立动态仿真模型验证了分析和结论,为单相接地故障的继电保护提供了参考。

The single-phase-grounding fault is a frequent failure in marine middle voltage power grid, it is easy to develop into serious short-circuit fault which threatens on the system operation safety. In order to understand such failure in detail, zero-sequence equivalent network is provided according to the practical MV ship grid, the distribution of zero-sequence current with single-phase-grounding fault in system is analyzed, and the zero-sequence current characteristic of magnitude and phase of fault and non-fault lines are liberated in the form of expressions and vector diagram. Finally, the provided analysis and conclusions are verified by dynamic simulation s established in MATLAB, which could provide reference of relay protection of single-phase-grounding fault.