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从法国第一颗地球观测航天器(SPOT1)到最新一代地球观测航天器(PPF1),它们的平台和太阳阵都大大增大了,为处理新的航天器结构,它们的控制算法也进行了修改。为提高航天器的性能,现已设计出不同的控制器和调制器,包括简单的 PD 控制器,直到考虑不同太阳阵结构的降阶 LQG。在精控模式中,对姿态速率稳定性要求很高,但受太阳阵定向机构旋转不规则性的干扰。业已证明,利用安装在中央本体上的飞轮是不能控制这种扰动的,所以定向机构只能采用闭路控制。太阳阵结构引起的各轴之间的耦合很强,且 SPOT4的阻尼极小,加上这种控制器较复杂,这些因素合在一起,就得采用经典控制到现代控制理论的各种分析工具。在推力器控制模式(主要是轨道控制模式)中,分析了由于这种控制模式采取与精控模式(协装模式)不同的结构配置方式而出现的一些特殊问题。因此有些推力器当利用简单的 PD 控制器控制时,它对太阳阵的挠性是不稳定的。这个问题通常不出现。但是,因为每一个推力器在挠性振型中有其自己的传递函数,所以必须认真分析挠性结构的推力器的控制问题。为处理 SPOT4的实际推力器结构,现已设计出一种 LQG 降阶控制器。
From France’s first space-based spacecraft (SPOT1) to the latest-generation Earth observation spacecraft (PPF1), their platforms and solar arrays have greatly increased, and their control algorithms have also been implemented to deal with new spacecraft structures modify. To improve the performance of spacecraft, different controllers and modulators have been designed, including simple PD controllers, until the reduced order LQG of different solar array structures is considered. In the fine control mode, the stability of the attitude velocity is very demanding, but it is disturbed by the rotation irregularity of the solar array orientation mechanism. It has been shown that the use of a flywheel mounted on a central body can not control such disturbances, so that the orienting mechanism can only be closed-circuit controlled. The strong coupling between the axes caused by the solar array structure and the very small SPOT4 damping, coupled with the complexity of such a controller, combine these factors with the use of a variety of analytical tools from classical control to modern control theory . In the thruster control mode (mainly the orbit control mode), some special problems that arise due to this control mode taking a configuration different from the fine control mode (co-ordination mode) are analyzed. As a result, some thrusters are unstable to the solar array’s flexibility when controlled with a simple PD controller. This problem usually does not appear. However, since each thruster has its own transfer function in the flexural mode, careful control of the thruster control of the flexure structure must be carefully analyzed. To deal with the actual thruster structure of the SPOT4, a LQG reduction controller has been devised.