论文标题
来自输入输出时间域测量值的Loewner框架中的数据驱动的二次建模
Data-driven quadratic modeling in the Loewner framework from input-output time-domain measurements
论文作者
论文摘要
在这项研究中,我们提出了一种纯粹的数据驱动方法,该方法使用Loewner框架(LF)以及非线性优化技术,通过仿射控制动力学系统推断二次,该系统从输入输出(I/O)时间域测量值中允许Volterra series(VS)表示。所提出的方法广泛采用优化工具来插值在VS框架中得出的对称广义频率响应函数(GFRFS)。 GFRF估计是从谐波激发下的准状态系统响应的傅立叶光谱(相和振幅)获得的。在开发的框架下对这些测量值进行适当的处理允许鉴定具有非平凡稳定平衡的低阶二次状态空间模型,例如在Lorenz '63强制系统中。因此,我们可以在仅从局部稳定的运营状态中收集测量后,可以实现可以与多个平衡分叉的系统的低阶全局模型识别。测试了开发的框架的几个尺寸和复杂性的示例,直到具有罗宾边界条件的粘性汉堡方程的测试用例。在后一种情况下,这项研究实施了采用数据驱动的减少模型推断的新方向,这些推断可以成功地提供适合控制的低阶准确替代预测模型。未来的指示和公开挑战总结了这项工作。
In this study, we present a purely data-driven method that uses the Loewner framework (LF) along with nonlinear optimization techniques to infer quadratic with affine control dynamical systems that admit Volterra series (VS) representations from input-output (i/o) time-domain measurements. The proposed method extensively employs optimization tools for interpolating the symmetric generalized frequency response functions (GFRFs) derived in the VS framework. The GFRF estimations are obtained from the Fourier spectrum (phase and amplitude) of the quasi-steady state system response under harmonic excitation. Appropriate treatment of these measurements under the developed framework allows the identification of low-order quadratic state-space models with non-trivial stable equilibria, such as in the Lorenz '63 forced system. We thus can achieve low-order global model identification for systems that can bifurcate to multiple equilibria after solely collecting measurements from a local stable operational regime. The developed framework is tested for several examples of increasing dimension and complexity, up to a test case of the viscous Burgers' equation with Robin boundary conditions. In the latter case, this study enforces new directions of employing data-driven reduced model inference that successfully can provide low-order accurate surrogate predictive models suitable for control. Future directions and open challenges conclude this work.