T2S2G: A Novel Two-Tier Secure Smart Grid Architecture to Protect Network Measurements

False data injection (FDI) attacks are a major security threat to smart grid (SG) communication systems. In FDI attacks, the attacker has the ability of modifying the measurements transmitted by smart grid entities such as smart meters, buses, etc. Many solutions have been proposed to mitigate FDI attacks in the SG. However, most of these solutions rely on centralized state estimation (SE), which is computationally expensive. To engulf this problem in FDI attack detection and to improve security of SGs, this paper proposes novel two-tier secure smart grid (T2S2G) architecture with distributed SE. In T2S2G, measurement collection and SE are involved in first tier while compromised meter detection is involved in second tier. Initially the overall SG system is divided into four sections by the weighted quad tree (WQT) method. Each section is provided with an aggregator, which is responsible to perform SE. Measurements from power grids are collected by remote terminal units (RTUs) and encrypted using a parallel enhanced elliptic curve cryptography (PEECC) algorithm. Then the measurements are transmitted to the corresponding aggregator. Upon collected measurements, aggregator estimates state using the amended particle swarm optimization (APSO) algorithm in a distributed manner. To verify authenticity of aggregators, each aggregator is authenticated by a logical schedule based authentication (LSA) scheme at the control server (CS). In the CS, fuzzy with a neural network (FNN) algorithm is employed for measurements classification. Our proposed T2S2G shows promising results in the following performance metrics: Estimation error, number of protected measurements, detection probability, successful detection rate, and detection delay.

Enlace de reconectadores a un sistema SCADA mediante una red de comunicaciones

El presente artículo detalla la metodología de enlace de una red de comunicaciones al sistema SCADA de la Empresa Eléctrica Azogues C.A. (EEA), partiendo de la necesidad de implementar reconectadores eléctricos a corto y mediano plazo; utilizando reconectadores automáticos OSM por su versatilidad y resistencia en aplicaciones al exterior, protocolos de comunicación IEC 870 DNP3 y Mod Bus para sistemas SCADA y unidades de terminales remotas. Mejorando de esta manera el servicio eléctrico suministrado en la ciudad de Azogues y sus parroquias. Para esto, se realiza el diseño de implementación de la red de comunicaciones que enlace los nuevos reconectadores adquiridos por la empresa; priorizando la infraestructura y recursos que tiene la misma, logrando de esta manera ubicar ocho de estos dispositivos, distribuidos en diferentes zonas de la ciudad utilizando en unos casos la red de fibra óptica y en otros alternativas de solución mediante radio enlaces para aquellos que se encuentran en puntos donde la infraestructura de red no permite su fácil acceso físico, con sus respectivos análisis técnicos y financieros. AbstractThe following paper details the link methodology from a communications network for the SCADA system at Azogues Power Company (EEA), starting from the need to implement electric reconnectors in the short and medium term; using automatic reconnectors OSM for their versatility and endurance when used outdoors, IEC 870 DNP3 communications protocols and ModBus for SCADA systems and remote terminal units. This way there is an improvement in the quality of the power supply service that is distributed in Azogues and its parishes. For this task, an implementation design of a communications network was done, in order to link the new reconnectors that were acquired by the company; setting a priority of the infrastructure and resources that it already had, achieving the placement of eight of these devices that were distributed in different areas of the city, using optic fiber in some cases and radio links in other situations when the network infrastructure didn’t allow the physical access to the facility; everything backed up with the correspondent technical and financial studies

Design and Implementation of an Automatic Hydrological Telemetry System

It is very significant for hydrological telemetry system to gather such real-time information as rainfall and water level of reservoir in order to improve forecasting level of flood prevention and flood disaster. In this paper, a novel hydrological telemetry system is presented. The system mainly consists of remote terminal units (RTUs) and monitoring center. The RTU is mainly designed to collect rainfall and water level, and send this information to the host computer in the monitoring center by GPRS network or other wireless network. The RTU is completely implemented on a low power consumption hardware platform. The host computer receives the data from the RTUs and analyzes them, then gives detailed tables, diagrams and some decision-making conclusions, which helps the competent authorities of the reservoir or the dam to realize remote monitoring and alarming system. The design principles, difficulties and skills are discussed detailedly in the paper. The low power consumption of the RTU and bit error rate for GPRS communication are both tested. A prototype is developed to validate above design cruces.

Security Protocol for Electrical Remote Terminal Units

We dissected disadvantages of the existing transmission protocols and improved its performance of dada communication security. We have proposed a security communication protocol, called as RTUSec, for remote terminal units. RTUSec adds a security layer to the existing three layer model, so that the data security is improved. After analyzing advantage and disadvantage of the present algorithms of cryptography and authentication for data communication, we have designed a security mechanism with DES and HMAC to deal with security problems like spoofing during the communication between Remote Terminal Units and controlling centers.

Design of Electric Vehicle Charging and Swapping Business Management Based on Platform - Plugin Structure

The dynamic compatibility of the device and communication protocols in operation management system of electric vehicles charging station was studied. Using NPAPI plug-in technique of Netscape series browser, the communication plug-in models are set up which separate the channel management and communication protocols translation from the charging and swapping business management system, and the cross-platform package is successfully developed. The protocols identifying, frames composing and decomposing are realized through designing the data structure and the functions in the modules. Practice indicates that with the communication plug-in, different remote terminal units can be compatible dynamically by operation management system on different platform, and charging business management of the system can be completed. Thus the business management system can run stably and efficiently.

A Protocol with Security Mechanism for Electrical RTU

We dissected disadvantages of the existing transmission protocols and improved its performance of dada communication security. We have proposed a security communication protocol, called as RTUSec, for remote terminal units. RTUSec adds a security layer to the existing three layer model, so that the data security is improved. After analyzing advantage and disadvantage of the present algorithms of cryptography and authentication for data communication, we have designed a security mechanism with DES and HMAC to deal with security problems like spoofing during the communication between RTUs and controlling centers.

Identification of Fault Location in Distribution Networks Using Multi Class Support Vector Machines

This paper presents a multi-class support vector machine (SVMs) approach for locating and diagnosing faults in electric power distribution feeders. Different from the traditional Fault Section Estimation methods, the proposed approach uses measurements available at the substation and remote terminal units (RTUs). To show the effectiveness of the proposed methodology, a practical 52 nodes, 3 feeder distribution systems (DS) with loads is considered. Practical situations in distribution systems, such as protective devices (circuit breakers/isolators) placed at different locations and all types of faults with a wide range of varying source short circuit (SSC) levels and fault impedances are considered for studies. The proposed fault location scheme is capable of accurately identify the fault type, location of faulted feeder section and the fault impedance. The results demonstrate the feasibility of applying the proposed method in practical distribution automation (DA) system for fault diagnosis.