Study of the multiple faults quantitative injection system for switch mode power supply and its applications

The further development of concept of all electric device puts forward higher requirements on reliability for switch mode power supply. Currently the fault injection method has widely used in reliability evaluation, fault diagnosis and prediction. For the fault injection method based on simulation, it spends lots time on building fault model and is difficult to completely conform to the actual unit under test. At present, the method based on physical implementation only studies on the single vulnerable unit of the power system. Aiming at these problems, a multiple faults quantitative injection system for switch mode power supply is built in this paper to solve these problems. At the first, analyze the reliability of a LED driver to determine the key components and the fault modes that will be injected into the actual circuit. Secondly, complete the software and hardware design of the system to realize the multiple faults quantitative injection, the signal acquisition, characteristic parameter extraction and so on. Finally, fault injection testing is carried out based on the system to set up the fault feature library, and the diagnosis results show that the system has good practicability. The system can provide test data for testability design, and provide a test platform for the research of fault diagnostics and prediction by faults quantitative injection.