Aiming at the problem that the design of aerospace electrical system mostly depends on its basic law and expert experience, and there is no digital design and simulation tool, the aerospace electrical system flow simulation technology based on fault injection is proposed. The technology of integration of design and simulation is used to simplify the complex process modeling and accelerate the process of building simulation system and simulation analysis. By analyzing the typical failure modes of the electrical system, the system architecture, function modeling, fault tracing and impact analysis are completed, and the platform scheme based on fault injection (FI) is designed. Aiming at the launch process example of the launch vehicle, two typical faults of the system power supply and communication are completed, and the fault injection simulation test and analysis are carried out. The practical results show that the platform provides information technology and innovative ideas for the verification of aerospace electrical system process scheme, reliability analysis and fault analysis, and can adapt to more complex aerospace system engineering tasks in the future.