Chen-Wei Yang

Cosimulation Environment for Event-Driven Distributed Controls of Smart Grid

This paper proposes a cosimulation environment for “hardware in the loop” or “software in the loop” validation of distributed controls in a Smart Grid. The controls are designed using model-driven engineering with the IEC 61499 Function Block architecture. These are connected with plant models, for example, in Matlab/Simulink, through communication channels such as UDP or TCP sockets. This solution enables multi-closed-loop plant-controller simulation. The communication between plant and controller is event-driven. In order to perform a realistic simulation, the proposed solution takes into account computation and communication delays on the controller side in Function Blocks and compensates model time on the plant side in Matlab model accordingly. Causality and accuracy of the method have been formally addressed. This approach has been tested and demonstrated with several Smart Grid-related examples.

Towards an IEC 61499 compliance profile for smart grids review and analysis of possibilities

The electric energy system is changing more and more into a Smart Grid. A key technology in order to transform the actual grid is the information and communication technology. This means that advanced management, automation, control and communication concepts and systems have to be developed in order to cope with changing and challenging future requirements in the intelligent grid; especially the large-scale integration of distributed energy systems and electric vehicles. As a result of this trend, the future grid will consist of a huge number of intelligent electronic devices in order to manage the distributed and complex nature of Smart Girds. In order to guarantee a high level of interoperability, which is a major requirement for Smart Grids and its related components and devices, the International Electrotechnical Commission has introduced the IEC 61850 standard for power utility automation. Since it covers only interoperability and communication issues, a proper design, modeling and implementation approach is required. The main aim of this paper therefore is to discuss the usage of IEC 61850 together with the IEC 61499 reference model for distributed automation and the development of a related IEC 61499 Compliance Profile for Smart Grids.

Smart Grid automation: Distributed protection application with IEC61850/IEC61499

This paper proposes solutions for distributed protection applications, to improve current and design of future protection schemes. This solution utilises advantages of fast and reliable peer-to-peer communication of IEC 61850 and interoperability and configurability of IEC 61499. The integration of the two standards improves protection schemes by decreasing fault clearing times and minimizes the effect of short circuit faults on sensitive loads. Additional advantages include the reductions of the number of hard-wired connections, especially in a large substation where all protection IEDs has a significant number of binary inputs and relay outputs. IEC 61499 is an open standard for designing distributed control systems to promote portability, interoperability and configurability, i.e. vendor independent, flexible and robust solutions. IEC 61499 can be used to represent programmable logic of power system devices, in a standard form and in a vendor independent way. The proposed distributed protection system is implemented and simulated using the developed co-simulation environment.

Programmable logic for IEC 61850 logical nodes by means of IEC 61499

IEC 61850 is a recent standard in substation automation system (SAS) aiming mainly at interoperability. Interoperability is achieved by standardizing communications and data between intelligent electronic devices (IEDs). Data in intelligent electronic devices are modelled in IEC 61850 using an object orientated approach as logical nodes. Although the IEC 61850 standardizes the data and communication in substation design, the implementation of control is intentionally left out of the standard. IEC 61499 function blocks has been proposed to fill the logic void of the IEC 61850 standard. In this paper, intelligent logical node (iLN) architecture is used, which combines both description and control within IEC 61850 logical nodes. An IEC 61850 application presented at the IEC TC57WG10 has been modelled using the iLN architecture with the addition of editable logics within the iLN architecture by means of IEC 61499 function blocks implemented in the ISaGRAF development platform.

Smart Grid applications with IEC 61499 reference architecture

This paper presents implementation of the Distributed Grid Intelligence (DGI) applications such as Intelligent Fault Management and Load Balancing using IEC61499 reference architecture. This enables system level design of distributed applications with a direct pathway to deployment to hardware. The use of IEC 61499 improves scalability, re-configurability and maintainability of automation software. Both applications were verified using co-simulation approach: control and power system simulated on PCs, and power system simulation on a PC networked with the number of distributed hardware running control algorithm. Both DGI applications were deployed to commercial programmable automation devices and embedded controllers. The use of IEC 61499 facilitates deployment of hardware independent function block model to the variety of compliant hardware. The paper also discusses distributed SCADA concept with IEC61499 implemented with the so-called Composite Automation Type (CAT) function blocks which combine functional and visual components. These blocks are used to implement human-machine interface of the FREEDM Smart Grid demonstrator reacting on plugging and unplugging of energy resources.

Intelligent IEC 61850/61499 logical nodes for smart metering

In this paper we present a prototypical smart metering infrastructure (MI) as part of the “distributed nervous system of SmartGrid”. Proposed MI is enabled with distributed programming infrastructure of the international standards IEC 61499, communication and design infrastructure of IEC 61850. The paper introduces IEC 61850 logical device for the smart meter. Based on this definition, the intelligent logical nodes architecture (iLN) is used to organize the distributed intelligence of a “swarm” of such smart meters. The proposed architecture has been applied to the novel Eaton PowerXpert intelligent commercial grade meter and tested in co-simulation environment.

SysGrid: IEC 61850/IEC 61499 based engineering process for Smart Grid automation design

The paper proposes a novel computer-aided model-based system engineering process for Smart Gird applications. The process is supported by the SysGrid tool that plays the roles of system configurator and device configurator. The design process starts with single line diagrams which are automatically transformed to executable function block specifications. The process is based on the Smart Grid control architecture that is a heterogeneous network of controllers communicating in a peer to peer manner. This “artificial nervous system” of the Smart Grid will be capable of self-healing and dynamic adaptation to renewable generation and ever-changing loads. The tool supports system-level design of automation logic in the form of function block networks with compliancy to IEC 61499. The capabilities of SysGrid are demonstrated through the process of designing a distributed protection application.

Towards implementation of Plug-and-Play and distributed HMI for the FREEDM system with IEC 61499

This paper presents an implementation of Plug-and-Play for the FREEDM system with IEC61499 function blocks. The FREEDM system is the envisioned next generation power distribution infrastructure which integrates DRER/ER with the legacy grid and is enabled by novel power electronics and distributed control. Plug-and-Play device integration is one of the key features of the FREEDM system that allows distributed renewable energy resources and distributed energy storage devices to be added or removed from the FREEDM distributed intelligent devices seamlessly. IEC61499 is an open standard for designing distributed control systems, which is investigated in the FREEDM project as an underlying system-level software architecture. Plug-and-Play is achieved by dynamic reconfiguration in IEC61499 to create the necessary function blocks during runtime for enabling Plug-and-Play between the DRER and the DGI devices. The developed Plug-and-Play technology is incorporated into the FREEDM infrastructure implemented in IEC61499 function blocks.

Cyber-physical components for heterogeneous modelling, validation and implementation of smart grid intelligence

This paper presents a practical framework to bring the cyber-physical block diagram models, such as Ptolemy, to the practice of industrial automation. Cyber-Physical Component (CPC) architecture is suggested. CPC aims at the improvement of design, verification and validation practices in automation of Smart Grid. IEC 61499 standard is used as a basis for this architecture. This architecture addresses several design software and system engineering challenges: right equilibrium between abstract representation and “executability” and round-trip engineering. An CPC exhibit such properties as portability, interoperability and configurability thanks to the reliance on open standards. The use of time stamp based execution paradigm adds determinism and predictability at the run-time.

SysGRID: IEC 61850 and IEC 61499 Standard Based Engineering Tool for Smart Grid Automation Design

The so called Smart Grid is said to be distributed in nature with an accompanying control architecture which is made up of a heterogeneous network of controllers communicating in a peer-to-peer manner. The paper proposes a novel computer-aided model-based system engineering process for the design of a Smart Grid applications from the initial design specification through to the validation of the control system and hardware deployment. The process is supported by the SysGRID tool, which plays the roles of a system configurator and device configurator adopted from the International Standard IEC 61850. SysGRID supports system-level design of automation logic in the form of function block networks compliant with the international standard IEC 61499. The capabilities of SysGRID are demonstrated through the process of designing a distributed protection application based on IEC 61850 and the resultant validation process in a close-loop co-simulation.