High Availability solution for medium voltage BPL communication networks

Nowadays production flows are modular, each module in the enterprise being specialized and used to achieve a particular task. In many cases the modules are interconnected and materials are sequentially processed in each module resulting a final, unique product or assembly. One typical such production module is a flexible cell/system using multiple robots. In such complex enterprise environments, providing continuous services for applications is a key component of a successful implementing of robotized manufacturing. High availability (HA) is one of the components contributing to continuous service provision for applications, by masking or eliminating both planned and unplanned downtime of systems and applications. This is achieved by eliminating hardware and software single points of failure (SPOF). The systems configured for high availability are a combination of hardware and software components configured to work together to ensure automated recovery in case of failure with a minimal acceptable downtime. A high availability solution will ensure that the failure of any component of the solution either hardware, software or system management, will not cause the application and its data to become permanently unavailable. High availability solutions should eliminate single points of failure through appropriate design, planning, hardware selection, software configuring, application control, carefully environment control and change management discipline. In short, one can define high availability as the process of ensuring an application is available for use by duplicating and/or sharing hardware resources managed by a specialized software component. A high availability solution in robotized manufacturing provides automated failure detection, diagnosis, application recovery, and node (robot controller) re integration. The chapter discusses the implementing of a high availability solution in a robotized manufacturing structure (cell, line). The solution is based on a High Availability Linux Cluster which is responsible for data availability and preservation on a NFS (Network File System) file system, and a second cluster – Fabrication Cluster (FC) which runs on Adept robot controllers, developed under the V+ programming language.

The deployment of smart grids has a major role to play in Japan’s aspiration to achieve sustainable energy systems. A smart grid in Japan is designed to have an intelligent monitoring system, which not only keeps track of all the energy coming in from diverse sources but also can detect where energy is needed through a two-way communication system that collects data about how and when consumers use power. This chapter examines the vision, concepts, and elements of Japan’s smart grid development. Smart grids are a part of the Japanese government’s ‘go green’ effort to bring Japan to a leadership position in environmental and energy sustainability. This analysis provides an overview of Japan’s major initiatives in deploying smart grids, including smart communities, large-scale smart grid pilot projects in four major cities, as well as overseas collaboration. Major smart grid awareness promotion bodies in Japan are discussed along with their important initiatives for influencing and shaping policy, architecture, standards, and traditional utility operations. Implementing a smart grid will not happen quickly because when Japan does adopt one, it will continue to undergo transformation and be updated to support new technologies and functionality.

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.

Criteria for smart grid deployment in Brazil by applying the Delphi method

More and more cloud computing services are handled by different Internet operators in distributed Internet data centers (IDCs), which incurs massive electricity costs. Today, the power usage of data centers contributes to more than 1.5% market share of electricity consumption across the United States. Minimization of these costs benefits cloud computing operators, and attracts increasing attentions from many research groups and industrial sectors. Along with the deployment of smart grid, the electrical real-time pricing policy promotes power consumers to adaptively schedule their electricity utilization for lower operational costs. This paper proposes a novel approach to enable electrical energy buffering in batteries to predictively minimize IDC electricity costs in smart grid. Batteries are charged when electricity price is low and discharged to power servers when electricity price is high. A power management controller is used per battery to arbitrate the charging and discharging actions of the battery. The controller is designed as a MPC-based (model predictive control) controller. To this end, an MPC power minimization problem is formulated based on a discrete state-space model with states of battery power level and cost. Extensive simulation results demonstrate the effectiveness of our approach based on real-life electricity prices in smart grid.

Due to complex and terrible channel characteristics of broadband power line communications (BPLC), the asymmetry between the upstream and the downstream is unavoidable, which may cause networking failure or routing instability. Aimed to solve this problem, this paper proposes an asymmetric channel based networking algorithm of the BPLC system, where the signal power adjustment is introduced into the hierarchical networking procedure. Thus, both of the upstream and the downstream can be guaranteed. In order to Evaluate this proposed algorithm, the simulation is conducted in terms of networking efficiency and success rate. Simulation results show that the proposed method is able to improve the supporting ability for data services of smart power grid with better networking performance.

Information and communication technology (ICT) infrastructure plays an important role to realize the full potential of Smart Grid applications. Smart grids utilize ICT entities to enhance efficiency, reliability and sustainability of power generation and distribution network. Majority of the architectures proposed hitherto focus only on a specific architectural aspect, like communication, storage, processing requirement, etc. Recent studies have shown that lack of knowledge on which architecture best satisfies certain information management requirements has hindered large scale smart grid deployments. In this paper, we investigate the cost-benefit analysis of four data processing architectures for various applications in smart grid. We introduce several key cost indicators to analyze hierarchical data processing architectures for the smart grid. In our evaluation, we consider realistic deployments for both dense and sparse environments. Results reported here are significant for smart grid designers, who can use them to discern the architecture that best fits the system requirements.

Broadband Power Line Communications (BPL) has the potential to play a significant role in smart metering and smart grid, due to its ability to transfer data with high rate and low latency over the existing infrastructure. The current planning and design of BPL networks for smart grid is manual, experience based, time consuming, and sub-optimal. In order to automate the planning process, compare multiple scenarios, and optimize the roll-out taking into account various input criteria and constraints, a planning tool is needed. In this paper, evaluation and validation results from the field test of an BPL planning tool for smart grid networks are presented. Two network setups has been first initiated in the laboratory to validate the concept of the BPL planning tool. The BPL planning tool has been then evaluated in the field. The simulation results of the BPL planning tool were fitting with the results of the field test.

In the US, smart grid and, more generally, clean energy policies enjoy a surprisingly wide consensus. Although the consensus is strong, smart grid deployment has been hindered by barriers established by a century old fossil fuel energy policy that has had the effect of entrenching both private firms and the regulatory bureaucracy. This paper will first describe the failures to modernize US electricity markets which have led to a failure to modernize the grid. The paper will then describe the key responses to overcoming those impediments. In brief, smart grid development is central not only to more competitive and more efficient electricity markets, it is central to a clean energy economy. However, before the smart grid can be fully deployed in the US, three things must occur. First, a national innovation policy must be further developed and federal resources must be, and are being, directed to smart grid innovations. Second, federal and state regulators, together with industry and consumers, must renegotiate the traditional regulatory compact with the specific intent of designing a clean energy future and with it a smart grid. And, third, incumbent private utilities will have to retool the way they do business to optimize their use of available funds and innovation opportunities.

In recent decades, virtualization as an abstraction from physical hardware has become a popular solution to resource isolation and server consolidation. With the surge in adoption of virtualization technologies, ensuring High Availability (HA) for applications hosted in virtualized environments emerges as an important problem and has garnered substantial attention. In this paper, we present a brief comparison of virtualization technologies from a HA perspective. The state-of-the-art HA solutions in two mainstream types of virtualized platforms (i.e., hypervisor-based platform and container-based platform) are respectively investigated in terms of limitations and features such as live migration, failure detection, and checkpoint/ restore. One of our key findings is that, compared with hypervisor-based platforms, HA features in container-based platforms are far from enough. From a HA perspective, extensions on top of container technologies are required.

Recently the communication network for power systems becomes one of the major focus in the development and deployment of smart grids. Particularly, how to validate if a real-time network can fulfill the strict requirements on communications, in a few ms or hundreds of μs? The basic approach is by precise simulations of the underneath communication network! However, the time requirements from distributed power applications cannot be met by the general data networks. There are no methods and tools available for such simulations, including the common network simulators OPNET and NS-2, due to the difficulty of simulating different time granularities. In this paper, we propose a simulation method for the modeling and operation of the protocols. First, we analyze the modeling and simulation of real-time Ethernet protocols that are widely used for connecting the most critical and fast response devices in smart grids. Second, we simulate the packet level performance of the real-time Ethernet. Third, we implement the modules for the protocol in the OPNET simulator. As an example, we model and simulate the EtherCAT, a real-time Ethernet protocol. Our extensive simulation results have demonstrated that the proposed methods are accurate and effective in modeling and simulating the packet-level performance of the real-time Ethernets. The methods can be also implemented in other tools to validate the timing critical devices in smart grids, such as super fast protections.

The future smart grid (SG) is envisioned as a very dynamic and decentralized energy network, where electricity is generated in distributed and dispersed ways, while the customers are not only consumers but also producers, playing an active role in energy generation. Bidirectional interactions between producers, consumers, and other entities are possible in the SG. Collaboration and near or real-time interactions are envisioned between all grid stakeholders, but these will depend upon timely communication, monitoring, and control capabilities. To realize the emerging SG infrastructure, several services are needed to empower all stakeholders and enable them to realize the expected interactions. The SG deployment and development have given rise to a strong interdisciplinary research. The SG is designed to integrate the most advanced communication, networking, and computing technologies into electrical power grids to make them smarter. The current status is that most of the blackouts and voltage disturbances could be prevented if we had better and faster communication devices and technologies to run the electrical grid. In order to make the current electrical power grid a smart grid, the design and implementation of a new communication and computing infrastructure for the grid are important research fields. These new technologies are seen as additional instruments that will be available to achieve targets for promoting competition, increasing the safety, reliability, and efficiency of electricity systems, and reducing the environmental impacts of energy generation. However, the boom in SGs also raises many economic and social questions.

The increasing demand for has necessitated the introduction of information and communication technologies (ICT) in the development of the smart grid. Advanced Metering Infrastructure (AMI) and Wireless Sensor Networks (WSNs) are contributing technologies. In this paper, a review on AMI and WSN in the smart grid is carried out. Also, the introduction of WSNs with AMI in the in-home energy management system of the smart grid is also presented with challenges faced in the deployment of WSNs for the smart grid. The low power and low-cost nature of WSN has presented itself as a technology that can be used with AMI and smart home appliances in achieving home energy management within the great goal of the smart grid.

In the last chapter, we talked about some basic things about MVCC in PostgreSQL, and what is bloat in the database and how it can be removed. We explained how autovacuum helps in removing bloat and improving performance. We also covered the best practices to execute maintenance activities like vacuum, reindex in detail. In this chapter, we will talk about the importance of High Availability (HA), and what information we need to build an HA solution and the procedures to implement it in PostgreSQL. We will cover some open source and enterprise tools to implement HA. We will also cover the importance of a pooler, and available poolers on the market and their implementation.

A systematic review of environmental and economic impacts of smart grids