太阳能电池阵跟踪驱动过程扰振特性分析

太阳能电池阵对日跟踪驱动过程所产生的扰动是限制高精度航天器技术指标提高的主要因素之一。为获取驱动扰动的规律性特征,本文将太阳能电池阵及其驱动装置考虑为相互耦合的整体系统,从主要驱动环节出发建立其机电一体化扰振分析模型和Simulink动力学仿真模块,通过试验算例验证模型正确性,并分析了电池阵刚柔耦合和质心偏置等因素对扰振特性的影响。结果表明:转速波动将激起电池阵低阶扭振模态,扰动频谱具有步进电动机驱动和柔性结构振动的频率特性,但扭振扰动对刚体运动规律影响很小;质心偏置会引起电池阵平动与转动耦合的空间振动,激扰面外弯曲振型,改变扰振频率分布和放大扰振分量幅值。

Characteristic Analysis of Disturbance Aroused by Solar Array Tracking Drive

The disturbance, aroused by sun-tracking drive of solar array, has become one of the major barriers for improving the performance of high-precision spacecraft. With the aim to obtain the regular characteristic of this disturbance, from the aspects of main driving steps, we presented an electromechanical integration model and a dynamic simulation program, based on Simulink software platform, of the coupling system that consists of solar array as well as drive assembly. The correctness was verified by comparing with experiment results, and effects of solar array rigid-flexible coupling and centroid bias to disturbance characteristics were analyzed. The results indicate that rotation speed fluctuation could activate low order torsion modes of solar array, and disturbance spectrums include both frequency characteristics of motor driving and structure vibration, but torsion vibration has little effect on rotation angle. The centroid bias of solar array could motivate translational-rotational coupling vibration, activate out-of-plane bending modes, change the distribution of disturbance spectrum, and increase the amplitude of disturbance.