Optimal TDMA Scheduling in Tree-Based Power-Line Communication Networks

Smart Grids (SG) may be the most significant technological change in the history of electric grids, that can help curb the looming energy crisis worldwide, with intelligent generation, transmission and distribution of energy using a robust communication network. Power lines are a very promising solution for carrying data to serve as broadband access network in the context of SG, along with the wireless communication techniques. This paper investigates the design and simulation of a digital communication system optimized for Power Line Communication (PLC) in Smart Grids. For the proposed PLC transceiver, we consider Discrete Multitone (DMT) modulation based on a modified bit loading technique for the subcarriers. Our results reveal that the proposed incremental bit loading algorithm enhances data rate, and reduces computation time, as compared to the originally proposed incremental bit loading algorithm for PLC.

Non Orthogonal Multiple Access (NOMA) for broadband communication in smart grids using VLC and PLC

This chapter presents related and current research on Smart Grids, Test Beds, AMI (Advanced Metering Infrastructure), PLC (Power Line Communication), and other emerging fields within OPNET and Power Line Communication. The author emerges in new research trends to provide adequate information on Smart House, Smart Grid communication, Smart Grid design challenges, and PLC and the Smart Grid. This chapter will pave the way for the information in upcoming chapters.

The success of the smart grid majorly depends on the advanced communication architectures. An advanced smart grid network should satisfy the future demands of the electric systems in terms of reliability and latency. The latest 4th-generation (4G) wireless technology, the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE), is a promising choice for smart grid wide area networks (WAN), due to its higher data rates, lower latency and larger coverage. However, LTE is not a dedicated technology invented for smart grid, and it does not provide Quality of Service (QoS) guarantee to the smart grid applications. In this paper, we propose an optimal LTE uplink scheduling scheme to provide scheduling timeguarantee at the LTE base station for different class of traffic, with a minimal number of total resource blocks. A lightweight heuristic algorithm is proposed to obtain the optimal allocation of resource blocks for each class of traffic. In the simulation, we compare the proposed optimal scheduling scheme and two existing scheduling schemes, the Large-Metric-First scheduling scheme and the Guaranteed Bit Rate (GBR) /Non-GBR scheduling scheme. The comparison results demonstrate that the proposed optimal scheduling can use less resource blocks to satisfy the scheduling time requirements than the other two existing scheduling schemes.

The inclusion of renewable energy in the conventional grid system and the digitalization of the various aspects of the power system have precipitated the transformation of the traditional grid system to a smart grid. Key to the implementation of the smart grid is various communication technologies. The emerging dominance of communication technologies in power systems applications is pivotal to modernizing the conventional grid system. This research presented an overview of the application of communication technologies in the digitalization of the power systems network. It reviews smart grid communication technologies, their features, relevance, and various roles being played toward delivering an effective electrical service to stakeholders. Hence, this study focused on wireless and wired communication technologies applicable to smart grid applications. Based on the review, each communication technology has its strengths and weaknesses; hence in selecting the most appropriate technology for application in a smart grid, a compromise must be made. Therefore, for choosing the most preferred communication technology in any smart grid application, it is important to deploy the efficacy of multi-criteria methods. To serve as a case study, a framework for selecting a communication technology for advanced metering infrastructure is proposed and applied. Based on the spectrum, data rate, and coverage range, the study revealed that WiMAX communication technology is the most preferred, followed by Zigbee; the least preferred communication technology for smart grid communication is Power Line Communication (PLC).

Broadband PLC (power line communication) has become one of the most important communication technologies for Smart Gird applications, especially for AMI (Advanced Metering Infrastructure) and HAN (Home Area Network). Currently, most broadband PLC products are based on OFDM, DMT or Spread-Spectrum technologies. Their performances differ from each other on certain circumstances. This paper proposes a performance testing model to test PLC devices' Transmitting Capacity and Noise Tolerance. Four PLC devices using different modulation technologies respectively are tested. In addition, the performances of different technologies are analyzed and some discussions are made. To reduce the affection of noise brought in by electric appliances, an "isolating socket" is introduced, which can filter the noises on the appliance side.

The smart grid (SG) promises to revolutionize power grid efficiency and reliability by bringing wide-area control and coordination between both power producers and widely distributed consumers. Such improvements, however, depend on reliable communication infrastructures for cooperation, thus creating an interdependence between wide area networks and the power grid. Real-time pricing (RTP) systems coordinate producers and consumers via price signals, and recent research has shown that network disruptions in RTPs can significantly harm or disrupt power grid operation. In this paper, we theorize and demonstrate how strategic network disruptions can further disrupt grid operations in ways that are profitable to a strategic adversary. We quantify the economic impacts of a strategic adversary that utilizes denial of service (DoS) attacks to gain a financial advantage in the power market, without compromising the integrity of the RTP signals. The adversary develops a strategy of when and where to launch DoS attacks by utilizing our algorithm that optimizes prices in her favor. A defender minimizes these financial gains by obfuscating the network targets, reducing the effectiveness of attacks. Our results provide insights to the dependability of RTP when deployed across disruptable wide-area best-effort communication networks.

ABSTRACTSmart grid is a new type of power grid that integrates advanced information communication technology and measurement technology into conventional power grids. It provides an efficient and intelligent energy service. However, the entities in the smart grid are easily hacked and sometimes even collapsed; then the whole grid system could be jeopardized. Therefore, the security of user privacy and communication in smart grids is still facing great challenges. In this paper, we propose a robust, distributed, and privacy-preserving aggregation scheme, RDPA for short, which uses the homomorphic Paillier cryptosystem technique combined with signature technique to ensure the confidentiality and integrality of users’ electricity consumption. In addition, we employ the threshold secret sharing technology and secret factors injection method to improve the robustness of smart grid systems. For example, RDPA can still run well even when a gateway is hacked. The experimental results and analysis demonstrate that RDPA can resist various attacks and protect user privacy, and its security and performance are better than other related schemes.

Smart grid has become the hot topic to domestic and foreign about the development trend of power grid in recent years, and communication technology is foundation of the development of smart grid; the paper forecasts the smart grid communications automation and development trend.Further from intelligent dispatching center, smart grid, smart distribution grid and users, in view of the existing and emerging intelligent and automatic application were communication needs analysis, and provide a reliable basis for the smart grid communications planning.

The concept of smart grid has emerged as a convergence of traditional power system engineering and information and communication technology. It is vital to the success of next generation of power grid, which is expected to be featuring reliable, efficient, flexible, clean, friendly, and secure characteristics. In this paper, we propose an efficient and privacy-preserving aggregation scheme, named EPPA, for smart grid communications. EPPA uses a superincreasing sequence to structure multidimensional data and encrypt the structured data by the homomorphic Paillier cryptosystem technique. For data communications from user to smart grid operation center, data aggregation is performed directly on ciphertext at local gateways without decryption, and the aggregation result of the original data can be obtained at the operation center. EPPA also adopts the batch verification technique to reduce authentication cost. Through extensive analysis, we demonstrate that EPPA resists various security threats and preserve user privacy, and has significantly less computation and communication overhead than existing competing approaches.

The popularity of the Power Line Communication (PLC) system has decreased due to significant deficiencies in the technology itself, even though new wire installation is not required. In particular, regarding the request for high-speed throughput to fulfill smart-grid requirements, Broadband Power Line (BPLC) can be considered. This paper approaches PLC technology as an object of simulation experimentation in the Broadband Power Line Communication (BPLC) area. Several experimental measurements in a real environment are also given. This paper demonstrates these experimental simulation results as potential mechanisms for creating a complex simulation tool for various PLC technologies focusing on communication with end devices such as sensors and meters. The aim is to demonstrate the potential and limits of BPLC technology for implementation in Smart Grids or Smart Metering applications.

In this paper, we present a signcryption scheme called CP_ABSC based on Ciphertext-Policy Attribute Based Encryption (CP_ABE)[7] to secure the multicast communications in smart grids that require access control, data encryption, and authentication to ensure message integrity and confidentiality. CP_ABSC provides algorithms for key management, signcryption, and designcryption. It can be used to signcrypt a message based on the access rights specified by the message itself. A user can designcrypt a ciphertext if and only if it possesses the attributes required by the access structure of the data. Thus CP_ABSC effectively defines a multicast group based on the access rights of the data specified by the data itself, which differs significantly from the traditional Internet based multicast where the destination group is predetermined and must be known by the data source. CP_ABSC provides collusion attack resistance, message authentication, forgery prevention, and confidentiality. It can be easily applied in smart grids to secure the instructions/commands broadcast from a utility company to multiple smart meters (push-based multicast) and the data retrieved from a smart meter to multiple destinations (pull-based multicast). Compared to CP_ABE, CP_ABSC combines encryption with signature at a lower computational cost for signcryption and a slightly higher cost in designcryption for signature verification. We also consider the adoption of attribute-based signature (ABS), and conclude that CP_ABSC has a much lower computational cost than ABS.

Based on the techno-economic pedagogical (TEP) method proposed in [1] that is suitable for designing Broadband over Power Lines (BPL) networks in transmission and distribution power grids, this paper examines the broadband potential of overhead low-voltage/broadband over power lines (LV/BPL) and medium-voltage/broadband over power lines (MV/BPL) networks. In this paper, on the basis of the set of linear simplifications and techno-economic metrics already presented in [1], TEP method demonstrates to undergraduate electrical and computer engineering (ECE) students the behavior of overhead LV/BPL and MV/BPL networks in terms of their modal transmission characteristics when different overhead LV/BPL and MV/BPL topologies occur. The contribution of this paper is four-fold. First, the factors influencing modal transmission characteristics of overhead LV/BPL and MV/BPL networks are investigated with regard to their spectral behavior and end-to-end channel attenuation. Second, the impact of the multiplicity of branches at the same junction is first examined. In the light of cascaded two-way power dividers, TEP method is extended so as to cope with more complex BPL topologies offering a new simplified and accurate circuital approximation. Third, apart from the broadband transmission characteristics of the entire overhead distribution power grid, a consequence of the application of TEP method is that it helps towards the intraoperability/interoperability of overhead LV/BPL and MV/BPL systems under a common PHY framework in the concept of a unified distribution smart grid (SG) power network. Fourth, TEP method can be demonstrated to undergraduate ECE students as case study in order to stimulate their interest for Microwave Engineering and Circuit/System Engineering courses. Citation: Lazaropoulos, A. (2015). Designing Broadband over Power Lines Networks Using the Techno-Economic Pedagogical (TEP) Method – Part II: Overhead Low-Voltage and Medium-Voltage Channels and Their Modal Transmission Characteristics. Trends In Renewable Energy, 1 (2), 59-86. doi: 10.17737/tre.2015.1.2.006

Characterized by time-of-using pricing, better capacity, and usage planning, smart grid has attracted considerable attention in recent years. However, one of the research challenges in smart grid is the privacy issue due to too much sensitive and real-time user data involved. In this paper, we propose a practical privacy-preserving aggregation scheme, named PPPA, for secure smart grid communications. PPPA utilizes the lightweight cryptographic aggregation technique to achieve provable security guarantee, the differential privacy technique to achieve privacy preservation of each individual user, and the quad tree structure to achieve failure tolerance. For data communication from users to control center, data aggregation is conducted directly on ciphertexts at local gateway without decryption, and the aggregation results are reported by relays to the control center. Through extensive analysis, we demonstrate that PPPA can not only provide authentication and guarantee the data integrity, but also achieve strong privacy-preserving for each user, and thus it is feasible in practical smart grid scenarios.

A systematic review of data protection and privacy preservation schemes for smart grid communications