Design and Application of Communication Gateway of EPA and MODBUS on Electric Power System

AbstractThrough the research of EPA Industrial Ethernet technology, MODBUS fieldbus technology, ARM embedded system and μC/OS-II real-time operating system, this paper discusses how to design and develop communication gateway of EPA and MODBUS. The communication gateway can realize bidirectional data transceiving on EPA protocol and MODBUS protocol. The communication gateway can provide a stable, secure, real-time and flexible solution for process control of the power plant

Evaluation of IEEE 802.1 Time Sensitive Networking Performance for Microgrid and Smart Grid Power System Applications

Proliferation of distributed energy resources and the importance of smart energy management has led to increased interest in microgrids. A microgrid is an area of the grid that can be disconnected and operated independently from the main grid when required and can generate some or all of its own energy needs with distributed energy resources and battery storage. This allows for the microgrid area to continue operating even when the main grid is unavailable. In addition, often a microgrid can utilize waste heat from energy generation to drive thermal loads, further improving energy utilization. This leads to increased reliability and overall efficiency in the microgrid area.As microgrids (and by extension the smart grid) become more widespread, new methods of communication and control are required to aid in management of many different distributed entities. One such communication architecture that may prove useful is the set of IEEE 802.1 Time Sensitive Networking (TSN) standards. These standards specify improvements and new capabilities for LAN based communication networks that previously made them unsuitable for widespread deployment in a power system setting. These standards include specifications for low latency guarantees, clock synchronization, data frame redundancy, and centralized system administration. These capabilities were previously available on proprietary or application specific solutions. However, they will now be available as part of the Ethernet standard, enabling backwards compatibility with existing network architecture and support with future advances.Two of the featured standards, IEEE 802.1AS (governing time-synchronization) and IEEE 802.1Qbv (governing time aware traffic shaping), will be tested and evaluated for their potential utility in power systems and microgrid applications. These tests will measure the latency achievable using TSN over a network at various levels of congestion and compare these results with UDP and TCP protocols. In addition, the ability to use synchronized clocks to generate waveforms for microgrid inverter synchronization will be explored

Functional safety networks and protocols in the industrial internet of things era

Functional safety networks are becoming of paramount importance in industrial systems, due to the progressive innovation introduced by the Industry 4.0 paradigm, characterized by high production flexibility, reliability and scalability. In this context, new and challenging applications have emerged such as hyperautomation, which refers to the combination of machine vision, robotics, communication, and learning, with the explicit involvement of humans. This requires the pervasive and ubiquitous connectivity encompassed by the Industrial Internet of Things, typically achieved via wireless systems. As an example, wireless communications are today fundamental to open up to new categories of autonomous devices that can actively collaborate with human personnel in the production process. This challenging scenario has important implications for safety. Indeed, a reliable coordination among sensors, actuators and computing systems is required to provide satisfactory levels of safety, especially in the case of innovative processes and technologies, such as mobile and collaborative robotics. Hence, it becomes imperative to ensure the correct transfer of safety-critical data via communication networks. In this paper, we address the challenges concerned with functional safety networks and protocols in Industrial Internet of Things ecosystems. We first introduce the design characteristics of functional safety networks and discuss the adoption of safety protocols over wireless networks. Then, we specifically address one of such protocols, namely Fail Safety over EtherCAT (FSoE), and provide the results of an extensive experimental session carried out exploiting a prototype system, implemented using commercial devices based on a WiFi network. Finally, the outcomes of the experiments are used as a basis for a discussion about future trends of functional safety in the Industrial Internet of Things era

Analysis of distributed ledger technologies for industrial manufacturing

In recent years, industrial manufacturing has undergone massive technological changes that embrace digitalization and automation towards the vision of intelligent manufacturing plants. With the aim of maximizing efficiency and profitability in production, an important goal is to enable flexible manufacturing, both, for the customer (desiring more individualized products) and for the manufacturer (to adjust to market demands). Manufacturing-as-a-service can support this through manufacturing plants that are used by different tenants who utilize the machines in the plant, which are offered by different providers. To enable such pay-per-use business models, Distributed Ledger Technology (DLT) is a viable option to establish decentralized trust and traceability. Thus, in this paper, we study potential DLT technologies for efficient and intelligent integration of DLT-based solutions in manufacturing environments. We propose a general framework to adapt DLT in manufacturing, and then we introduce the use case of shared manufacturing, which we utilize to study the communication and computation efficiency of selected DLTs in resource-constrained wireless IoT networks

Design and Implementation of a True Decentralized Autonomous Control Architecture for Microgrids

Microgrids can serve as an integral part of the future power distribution systems. Most microgrids are currently managed by centralized controllers. There are two major concerns associated with the centralized controllers. One is that the single controller can become performance and reliability bottleneck for the entire system and its failure can bring the entire system down. The second concern is the communication delays that can degrade the system performance. As a solution, a true decentralized control architecture for microgrids is developed and presented. Distributing the control functions to local agents decreases the possibility of network congestion, and leads to the mitigation of long distance transmission of critical commands. Decentralization will also enhance the reliability of the system since the single point of failure is eliminated. In the proposed architecture, primary and secondary microgrid controls layers are combined into one physical layer. Tertiary control is performed by the controller located at the grid point of connection. Each decentralized controller is responsible of multicasting its status and local measurements, creating a general awareness of the microgrid status among all decentralized controllers. The proof-of concept implementation provides a practical evidence of the successful mitigation of the drawback of control command transmission over the network. A Failure Management Unit comprises failure detection mechanisms and a recovery algorithm is proposed and applied to a microgrid case study. Coordination between controllers during the recovery period requires low-bandwidth communications, which has no significant overhead on the communication infrastructure. The proof-of-concept of the true decentralization of microgrid control architecture is implemented using Hardware-in-the-Loop platform. The test results show a robust detection and recovery outcome during a system failure. System test results show the robustness of the proposed architecture for microgrid energy management and control scenarios

Hybrid System of Distributed Automation

One of the most important tendencies in the development of the industrial automation is the application of intelligent control systems within factories, which focuses heavily on networked architectures. Following this line of thinking, the goal of this dissertation resumes itself in the implementation of a distributed system that controls two physical processes, where the system components not only trade information between each other, but also have that same information be accessible remotely and within HMI equipment. The controllers were conceptualized to offer different functional modes with high customization available. This system also takes resource of an OPC server, so it allows, not only the communication between different manufacturer PLC controllers but also the connection with remotes clients The implemented remote clients hold the intent of demonstrating the versatility of this architecture and are, namely, an operational historian that registers information and a data viewer, which allows the use of more advanced methods of monitoring

GUIDELINES FOR THE DESIGN OF ENHANCED, COST EFFECTIVE NETWORKS IN A MANUFACTURING ENVIRONMENT

Investigations into the transmission of real-time interactive speech over local area networks (LAN) in an industriai/commerciai environment to eventually obviate the need for a private automatic branch exchange and ultimately prepare the way for a single interactive integrated information system (PS) that provides work stations, which are networked via a LAN, with a fully interactive speech and graphics facility commensurate with the future requirements in computer integrated manufacturing (CIM). The reasons for conducting this programme of research were that existing LANs do not offer a real time interactive speech facility. Any verbal communication between workstation users on the LAN has to be carried out over a telephone network (PABX). This necessitates the provision of a second completely separate network with its associated costs. Initial investigations indicate that there is sufGcient capacity on existing LANs to support both data and real-time speech provided certain data packet delay criteria can be met. Earlier research work (in the late 1980s) has been conducted at Bell Labs and MIT. [Ref 25, 27 & 28], University of Strathclyde [Ref 24] and at BTRL [Ref 22 and 37]. In all of these cases the real time implementation issues were not fijlly addressed. In this thesis the research work reported provides the main criteria for the implementation of real-time interactive speech on both existing and newly installed networks. With such enhanced communication facilities, designers and engineers on the shop floor can be projected into their suppliers, providing a much greater integration between manufacturer and supplier which will be beneficial as Concurrent and Simultaneous Engineering Methodologies are further developed. As a result, various LANs have been evaluated as to their suitability for the transmission of real time interactive speech. As LANs, in general, can be separated into those with either deterministic or stochastic access mechanisms, investigations were carried out into the ability of both the: (i) Token Passing Bus LANs supporting the Manufacturing and Automation Protocol (MAP)—Deterministic and (u) Carrier Sense Multiple Access/Collision Detection (CSMA/CD) LANs supporting the Technical Office Protocol (TOP)— Stochastic to support real time interactive speech, as both are used extensively in commerce and manufacturing. The thesis that real time interactive speech can be transmitted over LANs employed in a computer integrated manufacturing environment has to be moderated following the tests carried out in this work, as follows:- The Token Passing LAN presents no serious problems under normal traffic conditions, however, the CSMA/CD LAN can only be used in relatively light traffic conditions i.e. below 30% of its designed maximum capacity, providing special arrangements are made to minimise the access, transmission and processing delays of speech packets. Given that a certain amount of delay is inevitable in packet switched systems (LANs), investigations have been carried out into techniques for reducing the subjective efifect of speech packet loss on real-time interactive systems due to the unacceptable delays caused by the conditions mentioned above

Fieldbus technology in industrial automation

http://ieeexplore.ieee.org/Fieldbus technology in industrial automation is not only relatively complex because of the number of solutions possible, but also, and above all, because of the variety of applications. Ironically, these in turn are responsible for the multitude of solutions available. If the analysis of the basic needs is relatively standard, as they will always involve connecting sensors, actuators, and field controllers with each other, the options in architecture are numerous and can impose the need for certain services. The required performances themselves and the quality of service expected fundamentally depend on the applications. This article traces this technology from its beginnings, which go back to the first industrial networks in the 1970's. The principal stages of development are recounted, from the initial requirement specifications to the current state of international standardization. The diverse technical solutions are then analyzed and classified. In particular, we study the temporal aspects, the medium access control protocols and application relationships

Stormwater Intelligent Control System (2005)

Water restrictions, pollution control, volume balances, and the emergence of stormwater utilities have lead to the development of an automated intelligent system (“I-Water”) for water use and control. With the use of this system, water stored in stormwater ponds or in the surficial aquifer is not discharged to surface waters because it is used to meet water demands, such as, lawn irrigation, environmental protection, agriculture, drinking and industrial uses. The drop in groundwater levels and the increasing use of reclaimed water illustrates a need for alternative water supplies. Ground water depletion is occurring which is adding to the destruction of wetland areas and reduced spring flows. The supply of available reclaimed water continues to rise but so does the demand for irrigation water. The automation, water quality monitoring, and database that an Intelligent Water (“I-Water”) controller provides can make stormwater reuse systems more feasible thus helping to reduce stormwater pollutant loadings, maintain watershed volume balances, and provide an alternative irrigation water supply. Using advanced technology is an efficient and effective way to manage this valuable freshwater resource. Telecommunications has made it possible to monitor water flow, valves, collect data, read instrumentation such as water quality sensors and control things remotely and in \u27real time\u27. Presented in this report is an automated controller integrating multiple sensors, used to collect data that can be monitored daily (if desired) via home or office computers and that can remotely control the flow of water using home or office computers. The automated controller can be operated at the installation site or via telecommunications from a remote site. The “I-Water” will make stormwater volume control using reuse systems more feasible by decreasing O&M costs. Remote on-line monitoring to provide more reliable data at a greater frequency of collection is possible with the “I-Water” or similar systems. The I-Water” will provide access to pollutant monitoring to assure that the stormwater is safe to use for non-potable purposes. The “I-Water” is available for deployment