Satellite Fault Diagnosis and Fault Tolerant Control Method Based on Adaptive Observer

Abstract

The invention relates to the technical field of satellite fault diagnosis and fault-tolerant control, and aims to propose a fault diagnosis method, which has good robustness to external interference, is not affected by external interference during the fault diagnosis process, and prevents false positives and missed negatives situation, and can effectively estimate the size of the fault; the present invention, based on the satellite fault diagnosis and fault-tolerant control method of the adaptive observer, first establishes the satellite kinematics and dynamics model under the influence of the actuator fault and external interference, and analyzes the effective factor of the fault on the satellite kinematics and dynamics model. system; secondly, design an observer for the satellite fault system, establish a residual evaluation function based on the output of the observer and the actual output of the system, and obtain the evaluation threshold to achieve the purpose of fault detection; then, when the fault is detected, design the automatic The observer is adapted to complete the fault diagnosis task; finally, based on the estimated value of the fault, a finite-time adaptive fault-tolerant controller is designed. The invention is mainly applied to the occasions of fault diagnosis and fault-tolerant control.

Description

technical field [0001] The invention relates to the technical field of satellite fault diagnosis and fault-tolerant control, in particular to the field of fault-tolerant actuator fault diagnosis and fault-tolerant control for a satellite attitude control system. Specifically, it involves satellite fault diagnosis and fault-tolerant control method based on adaptive observer. Background technique [0002] A spacecraft refers to a space vehicle that operates outside the atmosphere in accordance with the laws of celestial bodies. After decades of exploration and development, spacecraft technology has played an important role in national security, economic development, technological progress, environmental monitoring, weather forecasting, and disaster reduction and relief. The development of the aerospace industry is not only a manifestation of the progress of aerospace science and technology, but also a manifestation of the continuous growth of a country's comprehensive nationa...

AI Technical Summary

Problems solved by technology

However, when carrying out satellite fault diagnosis and fault-tolerant control design based on existing theoretical methods, the existing deficiencies are mainly reflected in the following aspects: (1) Most researchers mainly focus on satellite linearization models for fault diagnosis research, that is, in small The satellite attitude kinematic equation is linearized under the condition of attitude angle, and then the fault diagnosis and fault-tolerant controller design are carried out for the linearized satellite fault model. However, due to the nonlinearity of different degrees in the actual system, it is easy to cause the linear residual generator The diagnostic performance declines, and even false positives and negative negatives occur; (2) Existing fault diagnosis methods seldom consider the influence of spatial disturbance torque, or directly mix the disturbance torque and fault together for estimation, and cannot realize the fault-interference Effective decoupling, these will greatly limit the fault diagnosis accuracy of the satellite attitude control system, and it is difficult to guarantee the robustness of the fault diagnosis method; (3) Most of the previous work assumes that the system state is known, and the fault form is additive faults, while in satellite nonlinear models with multiplicative faults, the fault diagnosis is more complicated because the fault effects are mixed with the state or input of the system

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