【作者】 李安寿；

【导师】 张东来；

【作者基本信息】 哈尔滨工业大学 ， 电力电子与电力传动， 2014， 博士

【摘要】 由于具有便于模块化、集成化、易扩展、易维护等众多优点，分布式电源系统在航天航空、电力系统、新能源等领域得到了长足发展和广泛应用。然而，随着电源技术的发展和需求的提升，分布式电源系统的稳定性问题越来越成为一个日益突出的问题。本文针对分布式电源系统在稳定性判据、稳定性分析等方面存在的一些缺点和不足，从分布式电源系统的建模、小信号稳定性、大信号稳定性及遮挡对航天器电源系统稳定性影响等方面进行了深入的研究。本文建立了适合稳定性分析的分布式电源系统中的源模型、负载模型及开关变换器的小信号和大信号模型。特别是针对开关变换器大信号平均模型在CCM（Continuous Current Mode，电流连续模式）、DCM（Discontinuous Current Mode，电流断续模式）模式切换中存在的问题，提出了一种新的模式切换原则，可以更好地反映开关变换器的大信号动态特性。通过实验手段验证了模型在稳定性分析中的有效性，为后文的稳定性研究奠定了基础。在分布式电源系统的小信号稳定判据研究中，阻抗比判据是一种非常流行的方法。针对目前阻抗比判据存在的保守性问题，本文提出了一种使两级级联分布式电源系统小信号稳定的充要条件阻抗比判据，并讨论了任意集成的分布式电源系统的阻抗比判据。针对负载阻抗设计时圆禁区在波特图上难于计算的问题，提出了一种新的扇形禁区，可很容易地完成负载阻抗的设计。仿真研究证明了本文所提出的阻抗比判据及使用扇形禁区进行负载阻抗设计的有效性。针对Lyapunov直接法和直接仿真法在求取分布式电源系统这样一个非线性系统的吸引域时存在的缺点和不足，本文提出了一种基于间接数值仿真法和蒙特卡罗分析求取系统吸引域的方法。该方法使用上包络法来判定系统各状态变量是否收敛，以滤波器和变换器级联的分布式电源系统为例，求取了系统的吸引域。实验结果证明了使用文中方法求取吸引域的有效性。最后，本文分析了遮挡对航天器电源系统稳定性的影响。根据航天器构造复杂、太阳电池阵安装方式多样的特点，建立了航天器3D模型，考虑了构件的相对运动，提出了一种使用改进的投射阴影法和最小矩形法来精确生成太阳电池阵阴影图形的方法。以月球车为实例分析验证了生成阴影图形方法的正确性和快速性，并根据阴影图形计算了受遮挡后的太阳电池阵的输出特性，进而通过求取不同遮挡条件下系统的吸引域分析了遮挡对整个航天器电源系统稳定性造成的影响。更多还原

【Abstract】 Distributed power system (DPS) has been widely applied in many areas such as aerospace, aviation, power system, new energy resource, etc., due to its advantages of modularization, integration, extensibility, maintainability and so on. However, with the development of power technology and increasing need, there is an increasing demand in the stability and reliability of DPS. The stability problem of DPS becomes a gradually outstanding problem. Aiming at the shortcoming of stability criterion, stability analysis, etc. of DPS, this thesis conducts a relatively deep research from sides of the model establishment, small-signal stability analysis, large-signal stability analysis, etc. In addition, this thesis also researches the impact of shading on the stability of spacecraft power system.The source model, load model and switching converter’s small-signal and large-signal models of the DPS are established, which are suitable for stability analysis. Especially, a new mode transition principle is proposed to solve the mode transition problem between CCM (Continuous Current Mode) and DCM (Discontinuous Current Mode) of the switching converter’s large-signal averaged model. The proposed mode transition principle can better reflect the large-signal dynamic behavior of the switching converters. Experiment validation is made to ensure the effectiveness of the model in the stability analysis, which laid the foundation for the stability study of the following parts.Among the small-signal stability study of the DPS, the impedance criterion is one of the most popular methods. For the conservative problem of the present impedance criterion, a necessary and sufficient impedance stability criterion for the two subsystems cascaded DPS is proposed. And this thesis also discusses the impedance criterion of complex connected DPS. The sector forbidden region, which is a new forbidden region and can be easily calculated in the Bode diagram, is proposed to solve the calculation problem of the round forbidden region in engineering application. Examples and simulations are provided to verify the necessary and sufficient impedance stability criterion and the proposed sector forbidden region for the load impedance specification.To overcome the disadvantages of the Lyapunov direct method and the direct simulation method in estimating the region of attraction of the DPS, a typical nonlinear system, the indirect numerical simulation method based on Monte Carlo analysis is proposed. And the upper envelope method is used to judge the convergence property of the state variables of the system. Taking the filter and converter cascaded DPS as an example, this thesis estimates the system’s region of attraction. The validity of this method has been proved by experimental approaches.Finally, this thesis analyzes the impact of shading on the stability of spacecraft power system. According to the features of spacecraft having complex structure and solar array having various kinds of installation methods,3D model of spacecraft is established to consider the relative movement of the component and an algorithm of precisely calculating the shadow graph of solar array using the modified shadow map method and the minimal rectangle method is proposed. The example of lunar rover’s shadow graph calculation is given to validate the correctness and rapidity of the proposed algorithm. Based on the shadow graph, the solar array’s output characteristic is calculated, and the impact of shading on stability of spacecraft power system is analyzed through estimating the region of attraction of the whole system with different shading conditions.更多还原