A method of diagnosis satellite attitude control system unknown failure

The present invention provides a kind of methods for diagnosing satellite attitude control system unknown failure, the method includes four big steps: first, known fault detection statistic is constructed based on single class pivot analysis, the statistic utilizes the statistical information of data, judges whether test data is fault data, judges time of failure and determines the sample fault direction of test data；Secondly, realizing the isolation of known fault based on the angle between sample fault direction and known fault direction；Again, unknown failure detection statistic is constructed using sample fault direction and calculate corresponding detection threshold value, to realize the detection of unknown failure；Finally, being directed to the sample fault direction of unknown failure, the isolation of unknown failure is realized to the contributory index of statistic using variable, and find the hardware that breaks down.When unknown failure may occur for complicated satellite control system, unknown failure detection and isolation is may be implemented in this method, to improve the diagnosticability and reliability of satellite control system.