Experimental Study Of Dynamic Characteristics Of Solar Array Based On Time-Frequency Analysis

With the spacecraft function increased, electricity consumption of the spacecraft increases, the solar array structure presents the development trend of a large area and the high complexity, resulting in dynamics problems caused the attention of scholars at home and abroad. The solar array belongs to the large precious electrical and mechanical equipment, therefore, developing the study of the solar arrays dynamics has an important significance for improving the stability and reliability of the spacecraft.The paper completes the following three aspects work:Firstly, Taking into account the solar array nonlinear factors, such as clearance, friction, collision etc., it isn’t satisfied with requirements that the solar array experimental data is analysed by the application of traditional signal processing method. The introduction of time-frequency analysis is important for the study of the solar array dynamic characters. This article applies the ensemble empirical mode decomposition of the Hilbert-Huang transform to process and analysis the solar array dynamic characteristic data, overcomes the inherent defect of the mode mixing existing the empirical mode decomposition of the Hilbert-Huang transform, and the frequency resolution constant of the short time Fourier transform, the Wigner-Ville distribution, the wavelet transform, gets more accurate the solar arrays dynamic characters.Secondly, the experimental research is carried on the reduction ratio experimental device of the simulated solar arrays on the ground. Experimental contents include three aspects:1) the modal experiments of the simulated solar array system;2) under other experimental conditions keep unchanged, respectively change the synchronous rope preload and the knock point location of the simulated solar arrays. The collected data is processed and analyzed by utilized to the improved Hilbert-Huang transform. The analysis results show:1) As the synchronization rope preload increased, the solar array system stiffness can be enhanced to some extent, and the vibration caused by the hinge mechanism clearance is suppressed. But it isn’t good to be improved that the nonlinear characteristics of the system.2) It is no effect on the response of the sensor that the point thumped position changes. As the knock point location out-shift, the solar array system appears ’frequency drift’ non-linear characteristics due to the Structural flexibility and clearance, which increases the difficulty of the solar array system signal analysis and fault detection.Finally, in order to easy to compare the Hilbert transform method based on EEMD with other time-frequency analysis methods, and process the measured experimental data. It is established by using the GUI of MATLAB that a set of simple system of modern signal processing methods.