Research On Fault Diagnosis Of Spacecraft Power Conditioning Unit

With the rapid development of economy and military in our country,the pace of exploring space is accelerating.Spacecraft is expensive and has a special strategic position.More and more attention are paid on the safety and reliability of spacecraft.However,the structure of the spacecraft is complex and the working environment is harsh,which increases the probability of failure.As an important energy system on the spacecraft,the spacecraft power supply system is responsible for the uninterrupted power supply to electrical equipment during the operation of the spacecraft.Once a failure occurs,it may cause serious accidents.Spacecraft power conditioning unit is the brain of power regulation in power supply system.Its importance is self-evident.Therefore,it is of great significance to study the fault of spacecraft power conditioning unit.This paper mainly studies from the following aspects:(1)Spacecraft power supply systems with different topologies are studied,and the working rules and control strategies of the corresponding spacecraft power supply systems are summarized.(2)The models of each component of power controller for spacecraft power supply are established.The injection methods of shunt,charge and discharge regulators are studied,and the effect of faults is simulated and the reasons are analyzed.(3)According to the fault characteristics of each component of spacecraft power conditioning unit,the fault tree of spacecraft power conditioning unit is listed,and the testability analysis of spacecraft power conditioning unit based on multi-signal flow graph model is carried out.(4)The fault characteristic parameters of shunt,battery charging regulator and discharge regulator are extracted,and the sensor placement and fault diagnosis strategy are formulated based on testability analysis.(5)A fault diagnosis system for spacecraft power conditioning unit based on LabVIEW and Matlab/Simulink is developed.By injecting fault into the diagnosis system,the correctness of selecting fault characteristic parameters and the validity of the diagnosis method are verified.