Real-time hybrid testing is a technology which allows the coupling of simulations and component tests in order to simulate complex system dynamics. Delays and time lags caused by actuator dynamics and signal processing deteriorate the stability of the tests in many cases. The application of adaptive feedforward filters to hybrid testing enables circumventing this problem. The stability of the filter itself, however, can be affected by the choice of the algorithm parameters or changes in dynamics of the system being tested. Test safety requirements and practical considerations require a failsafe implementation. In this paper, we propose a method for adjusting the parameters of the adaptive feedforward filter based on power-flows in the test setup. The objective is to maintain a passive behavior of the actuation and control system. The stabilization acts on the leakage factor and the adaptation gain of a least-mean-squares adaptation law. A simple numerical system is used to investigate the effect of the algorithm parameters on the stabilization. The method was applied to an experimental setup including a nonlinear stiffness. Several originally unstable configurations were stabilized, the adaptation process could be continued and interface synchronization was achieved in all test cases.

中文翻译：

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混合测试中自适应前馈滤波器的基于功率流的稳定

实时混合测试是一种允许将模拟和组件测试结合起来以模拟复杂系统动力学的技术。在许多情况下，致动器动力学和信号处理引起的延迟和时间滞后会降低测试的稳定性。自适应前馈滤波器在混合测试中的应用可以避免这个问题。然而，滤波器本身的稳定性会受到算法参数选择或被测系统动态变化的影响。测试安全要求和实际考虑需要故障安全实施。在本文中，我们提出了一种基于测试装置中的潮流来调整自适应前馈滤波器参数的方法。目标是保持驱动和控制系统的被动行为。稳定作用于泄漏因子和最小均方适应法则的适应增益。一个简单的数值系统被用来研究算法参数对稳定性的影响。该方法应用于包括非线性刚度的实验装置。稳定了几个原本不稳定的配置，可以继续适配过程，并在所有测试用例中实现接口同步。