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The IEC 61850 standard has brought new opportunities for developing Centralized Substation Protection and Control (CPC) platforms to be used in digital substations. The CPC operation requires a proper signal processing module that provides the necessary parameters and signals accurately and at times needed to ensure the platform’s control and protection services can operate correctly. This paper proposes and implements a sampled values-analog processing module (SV-APM) for a software-based CPC in a digital substation developed in the framework of the EPICS project. The SV-APM decodes the digital messages published by merging units and extracts the information required by control and protection functions implemented in a software-based CPC platform. To check SV-APM performance, a set of tests is carried out using Real-time digital simulator (RTDS) and EPICS platform in Hardware in the Loop configuration (HiL). These tests evaluate SV-APM behavior against disturbances in communication channels, voltage and current variations, harmonic contents and frequency variations. Furthermore, latency tests are carried out to evaluate CPC response times. From tests, it is concluded that SV-APM output satisfactorily fulfills all the time response and accuracy requirements demanded during its development.

This paper deals with the design problem of multivariable Proportional-Integral-Derivative (PID) controllers for square and stable multivariable processes when a linear margin at the Nyquist plot is considered as robustness specification for each closed loop. A tuning method is developed based on the new concept of equivalent loop transfer function, which is proposed for centralized control and allows an independent design for each loop considering the interactions with the other loops through an iterative procedure. For the k-th loop, the PID parameters of the k-th column of the control matrix are calculated in each iteration by a linear programming optimization that maximizes the integral gains while fulfilling the robustness specification and achieving static decoupling. The method uses a frequency response array as representation of the process, which allows its applicability to systems with multiple time delays without requiring model reductions or approximations. The effectiveness of the method is illustrated by means of two simulation examples with dimensions $2 \times 2$ and $3 \times 3$ . Comparisons with other centralized control methodologies show that the proposed approach achieves similar or greater performance and a remarkable better disturbance rejection response.

With the rapid advancement of connected and autonomous vehicles (CAV) in terms of testing and usage, the implementation of the autonomous interchange in the real world has become more realistic than before. Since the beginning of the last decade, the concept of autonomous intersection has been developed with slightly different techniques. This paper introduces a next-generation interchange control algorithm (NIC) that deals with service interchange terminals for the CAV with the ability to adjust the dimensions and geometric designs. It proposes six different geometric designs that have been modeled in a simulation software package (VISSIM) to employ the NIC algorithm. The system depicted a real-world scenario of an interchange with a slight modification on the geometric design to provide smoother entry to the interchange terminal. The analysis of the proposed designs in terms of throughput, capacity, delay, and volume-to-capacity (V/C) ratio indicated different performance measurements based on the analyzed traffic movements. Tight turn with one left dedicated turn provided the highest performance, while wide turn with two left shared turns indicated the lowest performance. Both NIC designs demonstrated significantly higher throughputs and significantly lower delays compared to a current traffic signal system. By applying the NIC with the existence of the CAV, the operation of highway interchange can be significantly improved.

The vast majority of routing approaches for vehicular ad hoc networks (VANETs) are distributed, which are ineffective to exploit the global networking information and easily lead to local optimum, appearing as sparse connectivity and network congestion. Recently, by combining software-defined network architecture together with VANETs, software-defined VANETs (SDVN) is widely concerned, which shows the benefits of centralized control. In this paper, we propose a hierarchical geography routing protocol for SDVN. First, the protocol divides a large region into multiple small grids according to the geographical location and finds a series of grids with good connectivity based on real-time grid vehicle density and historical vehicle transfer probability between grids. Second, we construct a path cost function with load balancing and keep two paths with minimal costs from the selected grids. Finally, a series of relay nodes on each selected path are filtered for routing according to node utility. Simulation results show that the proposed routing algorithm achieves significant gains in terms of delivery ratio, throughput, average delay, and average hop count compared with several existing routing protocols.

Dynamic smart grid operations require that utilities that incorporate intermittent renewable energy resources provide creative and inclusive solutions to reduce and shift electrical demand. Commercial building HVAC systems have been used as a dispatchable load, but are limited by the lack of interoperability. Increased operability can be achieved using a secure and reliable interconnection device, which can provide direct bidirectional communications between the utility and the building automation system (BAS) controllers. This paper developed and tested a building automation intrusion detection system (BAIDS) that can provide a cyber-secure connection between public and private BAS networks. The BAIDS was used in a hardware-in-the-loop experiment that connected an actual photovoltaic array with a BAS control test bed and a building zone model. The BAIDS device allowed for critical control signals to pass from the public network directly to a fan controller in a BAS private network. At the same time, the BAIDS device provided intrusion detection monitoring to identify malicious activity. The network traffic was evaluated using an adaptive resonance theory (ART) artificial neural network. The ART algorithm was able to learn normal traffic activity on the private and public networks. The algorithm was then used to detect unauthorized attempts to access the interconnection device and a malicious cyber-physical attack on the BAS.