Annual Reviews in Control最新文献

This article provides an overview of a new approach to designing controllers for nonlinear systems using data-driven control. Data-driven control is an important area of research in control theory, and this novel method offers several benefits. It can recreate from a data-centred perspective many of the results available in the model-based case, including local stabilization based on Taylor or polynomial expansion, absolute stabilization, as well as approximate and exact feedback linearization. Moreover, the method is analytically and computationally simple, and permits to infer regions of attraction and invariant sets, also when the data are corrupted by noise.

This paper reviews the evolution of Internal Model Control (IMC) techniques developed so far for unstable processes. The IMC strategy has shown significant results over the past two decades, including recent inclusions of fractional-order approaches. After a comprehensive study of various methods, the critical tuning methods and structural changes are clearly accumulated with their significance and limitation concerning controlling unstable time-delay systems. The comparisons with main structural changes and filter designs are also included in the numerical study and in discussion. Finally, the key research gaps and future motivations are indicated in the IMC approaches, considering available methods in the literature.

With an increasing focus on climate action and energy security, an appropriate mix of renewable energy technologies is imperative. Despite having considerable global potential, wave energy has still not reached a state of maturity or economic competitiveness to have made an impact. Challenges include the high capital and operational costs associated with deployment in the harsh ocean environment, so it is imperative that the full energy harnessing capacity of wave energy devices, and arrays of devices in farms, is realised. To this end, control technology has an important role to play in maximising power capture, while ensuring that physical system constraints are respected, and control actions do not adversely affect device lifetime. Within the gamut of control technology, a variety of tools can be brought to bear on the wave energy control problem, including various control strategies (optimal, robust, nonlinear, etc.), data-based model identification, estimation, and forecasting. However, the wave energy problem displays a number of unique features which challenge the traditional application of these techniques, while also presenting a number of control ‘paradoxes’. This review articulates the important control-related characteristics of the wave energy control problem, provides a survey of currently applied control and control-related techniques, and gives some perspectives on the outstanding challenges and future possibilities. The emerging area of control co-design, which is especially relevant to the relatively immature area of wave energy system design, is also covered.

In this paper, leak detection and localization in water distribution networks will be reviewed. In particular, the paper presents the evolution of the methods from model-based towards data-based approaches, listing, describing and comparing the main and/or most recent methods of both categories. Besides, the practical applicability in real water utilities of different existing methods is discussed, outlining the advantages and limitations of model-based and data-driven methods for this task. A well-known case study is used to compare some of the more promising methods and illustrate their performances. Perspectives of the future evolution of the current existing methods are also provided.

The Kalman filter (KF) is a popular state estimation technique that is utilized in a variety of applications, including positioning and navigation, sensor networks, battery management, etc. This study presents a comprehensive review of the Kalman filter and its various enhanced models, with combining the Kalman filter with neural network methodologies. First, we provide a brief overview of the classical Kalman filter and its variants, including the extended Kalman filter (EKF), unscented Kalman filter (UKF), cubature Kalman filter (CKF), etc. It is pointed out that the traditional Kalman filter faces two main problems: system model and noise model parameter identification. To overcome these obstacles, researchers have developed novel solutions by integrating machine learning techniques with the Kalman filter. Secondly, this paper classifies the related models into two categories: both the internal cross-combination of the Kalman filter and neural network and their external combinations. Two different hybrid models and typical structures show that the hybrid model performs more accurately and robustly overall. Finally, the characteristic of the two hybrid models is summarized so that readers can understand them more intuitively.

Multi-time scale techniques based on singular perturbations and averaging theory are among the most powerful tools developed for the synthesis and analysis of feedback control algorithms. This paper introduces some of the recent advances in singular perturbation theory and averaging theory for continuous-time dynamical systems modeled as ordinary differential equations (ODEs), as well as for hybrid dynamical systems that combine continuous-time dynamics and discrete-time dynamics. Novel multi-time scale analytical tools based on higher-order averaging and singular perturbation theory are also discussed and illustrated via different examples. In the context of hybrid dynamical systems, a class of sufficient Lyapunov-based conditions for global stability results are also presented. The analytical tools are illustrated through various new architectures and algorithms within the context of adaptive and extremum-seeking systems. These tools are suitable for the study of model-free optimization and stabilization problems that require the synergistic use of continuous-time and discrete-time feedback. The paper aims to acquaint the reader with a range of modern tools for studying multi-time scale phenomena in optimization and control systems, providing some guidelines for future research in this field.