NeTS: Small: Towards Efficient and Reliable Communication Infrastructure for Network Controlled Cyber Physical Systems with Application in Smart Grids

典型的网络物理系统（cps），如智能电网、无人机（uav）和机器人网络，由物理动力学、传感器、通信网络和控制器组成。将系统测量数据从传感器传递到控制器的通信网络在cps中起着关键作用，类似于人类的神经系统。传统的数据通信网络（如蜂窝网络或WiFi）只关注数据包的传输，而CPS的最终目标是控制物理动态（如稳定电网中的电压和频率）。因此，由于设计目标不匹配，传统的通信网络设计在cps环境下可能不是最佳的。因此，迫切需要研究cps中通信网络的设计，以提高cps的敏捷性、鲁棒性和效率。本课题研究如何有效地设计CPS的系统动态感知通信网络，该网络集成了通信、网络、控制和动态系统等领域，并应用于关键基础设施中CPS的重要和不断发展的领域。项目具体研究任务如下：(a)混合系统联合设计：利用混合系统理论对CPS进行建模，将通信网络的运行模式建模为混合系统的离散状态，将物理动力学建模为连续状态。通过优化混合系统动力学，对通信子系统和控制子系统进行联合设计；(b)通过信息接口分开设计：通信和控制子系统分开设计，并通过指定的接口（如通信服务质量（QoS）或虚拟队列映射）进行桥接；(c)与弹性数据流量共存：实时数据流量可能与弹性数据流量（如Internet数据）共享相同的通信资源。将弹性数据流量的排队动力学与CPS的物理动力学集成在同一框架中，研究了弹性和实时两种流量的调度问题；(d)在智能电网中的应用与实现：在前两项任务中获得的原理、算法和协议作为CPS的案例研究应用于智能电网并得到证实。重点研究了集中式和分散式微电网的电压控制。它们分别在通信和控制子系统联合仿真的软件仿真试验台和使用USRP板和微电网试验台的硬件仿真试验台上实现。

Typical cyber physical systems (CPSs), such as smart grid, unmanned aerial vehicles (UAVs) and robotic networks, consist of physical dynamics, sensors, communication network and controllers. The Communication network, which conveys system measurements from sensors to controllers, plays a key role in CPSs, similarly to the nerve system in human beings. Traditional data communication networks (e.g., cellular networks or WiFi) focus only the delivery of data packets, while the ultimate goal of a CPS is to control the physical dynamics (e.g., stabilizing the voltages and frequencies in power networks). Hence, the traditional design of communication network may not be optimal in the context of CPSs, due to the mismatched goals of designs. This results in a pressing need to study the design of communication networks in CPSs, which helps to enhance the agility, robustness and efficiency of CPSs. This project studies how to efficiently design system-dynamics-aware communication networks for CPS, which integrates the areas of communications, networking, control, and dynamical systems, and has applications to the important and growing field of CPS in critical infrastructures.The project specifically addresses the following research tasks: (a) Joint Design as Hybrid Systems: The theory of hybrid systems is used to model CPS, in which the operation mode of communication network is modeled as the discrete state of a hybrid system, while the physical dynamics are modeled using the continuous state. The communication and control sub-systems are designed jointly by optimizing the hybrid system dynamics; (b) Separate Design via Information Interface: The communication and control sub-systems are designed separately and are bridged via designated interfaces, such as communication quality of service (QoS) or virtual queue mapping; (c) Coexistence with Elastic Data Traffics: The realtime data traffic may share the same communication resource with elastic data traffics such as Internet data. The queuing dynamics of elastic data traffic and the physical dynamics of CPS are integrated in the same framework, and the scheduling for the two types of traffics (elastic and realtime) is studied; (d) Application and Implementation in Smart Grid: The principles, algorithms, and protocols obtained in the previous two tasks are applied and substantiated in smart grids as a case study for CPS. The voltage control in microgrid, both centralized and decentralized, is particularly studied. They are implemented in both software simulation testbed, in which the communication and control sub-systems are co-simulated, and hardware testbed using USRP boards and the microgrid testbed.