Communication networks as smart infrastructure systems play an important role in smart girds to monitor, control, and manage the operation of electrical networks. However, due to the interdependencies between communication networks and electrical networks, once communication networks fail (or are attacked), the faults can be easily propagated to electrical networks which even lead to cascading blackout; therefore it is crucial to investigate the impacts of failures of communication networks on the operation of electrical networks. This paper focuses on cascading failures in interdependent systems from the perspective of cyber-physical security. In the interdependent fault propagation model, the complex network-based virus propagation model is used to describe virus infection in the scale-free and small-world topologically structured communication networks. Meanwhile, in the electrical network, dynamic power flow is employed to reproduce the behaviors of the electrical networks after a fault. In addition, two time windows, i.e., the virus infection cycle and the tripping time of overloaded branches, are considered to analyze the fault characteristics of both electrical branches and communication nodes along time under virus propagation. The proposed model is applied to the IEEE 118-bus system and the French grid coupled with different communication network structures. The results show that the scale-free communication network is more vulnerable to virus propagation in smart cyber-physical grids.

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Recently, a new type of motor, synchronous reluctance motor (SRM), has attracted wide attention from academia and industry because of its potential applications in fans, pumps, and elevator traction systems. Compared with traditional motors, these motors have lower eddy-current loss, less torque ripple, reduced noise, smaller moment of inertia, and faster dynamic response, and they provide a greater operating efficiency and safety and are simpler and easier to maintain. However, the ontology design and operation control of SRMs continue to be significant hurdles that must be overcome prior to practical implementation. In order to facilitate the practical application of SRMs in industry, at the invitation of an elevator company, we designed a large SRM for elevator traction. Herein, we describe the design of the proposed system and present a theoretical analysis of the system. Furthermore, we fabricate a real prototype and the corresponding control system and perform an experimental test under the rated operating conditions and 1.5× overload conditions in order to verify the SRM's performance. The results of the experimental testing were satisfactory and consistent with the theoretical calculations. At present, we have entered the stage of small-batch trial production and we expect to ultimately implement this novel design. Further, the approach to ontology design and operation control in this study can be used to inform the future development of novel SRMs.

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