Cyber-Physical System Enabled Smart Grid Based Optimal Controller placement

The controller placement problem

Abstract: Network architectures such as Software-Defined Networks (SDNs) move the control logic off packet processing devices and onto external controllers. These network architectures with decoupled control planes open many unanswered questions regarding reliability, scalability, and performance when compared to more traditional purely distributed systems. This paper opens the investigation by focusing on two specific questions: given a topology, how many controllers are needed, and where should they go? To answer these questions, we examine fundamental limits to control plane propagation latency on an upcoming Internet2 production deployment, then expand our scope to over 100 publicly available WAN topologies. As expected, the answers depend on the topology. More surprisingly, one controller location is often sufficient to meet existing reaction-time requirements (though certainly not fault tolerance requirements).

Cybersecurity in Distributed Power Systems

Abstract: This paper presents the application of cybersecurity to the operation and control of distributed electric power systems. In particular, the paper emphasizes the role of cybersecurity in the operation of microgrids and analyzes the dependencies of microgrid control and operation on information and communication technologies for cybersecurity. The paper discusses common cyber vulnerabilities in distributed electric power systems and presents the implications of cyber incidents on physical processes in microgrids. The paper examines the impacts of potential risks attributed to cyberattacks on microgrids and presents the affordable technologies for mitigating such risks. In addition, the paper presents a minimax-regret approach for minimizing the impending risks in managing microgrids. The paper also presents the opportunities provided by software-defined networking technologies to enhance the security of microgrid operations. It is concluded that cybersecurity could play a significant role in managing microgrid operations as microgrids strive for a higher degree of resilience as they supply power services to customers.

Controls for Smart Grids: Architectures and Applications

Abstract: Control is and will continue to be a key discipline for realizing the objectives of smart grid initiatives. Research in control science and engineering is not limited to one or a few application concepts but is pervasive across the smart grid ecosystem. The principal contribution of this paper is to review, from a system-architectural perspective, how control enables smart grid applications. Application “templates” are presented for direct load control, automated demand response, microgrid optimization, control for distribution grids, wide-area control, and market-centric control. Technological developments, including in power electronics, that are enabling smart grid control research and applications are also itemized and two cross-cutting needs/opportunities for future research discussed. We conclude with a summary of a recent status report on the progress that has been made in the United States, noting also the challenges to further progress, in renewable generation, energy efficiency, and carbon reduction.

Aggregation Points Planning in Smart Grid Communication System

Abstract: Aggregation Point (AP) in neighborhood area network (NAN) plays a key role on smart grid communication. The AP stores and forwards data stream between home area network (HAN) and wide area network (WAN) in the smart grid. In this letter, we study how to plan the APs in the smart grid to minimize the total deployment cost of the opening APs and the connecting cost between the APs and the HANs while considering the capacity of the APs and the traffic demands of the HANs. Our general formulation leads to an NP-hard problem and an approximation algorithm is developed to address it. Numerical results show that our proposed algorithm has great advantages over other heuristic methods. Furthermore, our proposal gives a performance-guaranteed planning scheme of the APs for smart grid communication.

On the load balanced controller placement problem in Software defined networks

Abstract: In Software defined networks (SDNs), controller placement is an important problem which will affect the performance of the network directly. At present, there have been some studies on the controller placement problem in SDN from different aspects such as delay, capacity, reliability and load balance. In this paper, the controller placement problem is discussed from the aspect of delay and load balance at the same time. More precisely, for a given topology, we study how to choose locations of the multiple controllers to minimize the average delay or the worst delay of all control paths under the consideration of load balance. The trade-off between delay and load balance is investigated through simulation. The results show that the load of the control plane can be well balanced with only a little increment of the objective delay.