Light-weight IEC 61850 GOOSE based LoM protection for smart grid

This paper presents a novel Loss of Mains (LoM) protection method based on IEC 61850 General Object Oriented Substation Event (GOOSE) protocol. With the increased penetration of distributed generation (DG), the requirements for LoM or anti-islanding protection has become common in the electric utilities. The development of Smart Grids including extensive communication capabilities enables also communication based LoM approaches. Since IEC 61850 standard based systems are the mainstream in the substation communication, expanding this technology deeper in the distribution network provides interesting solution for communication based LoM protection. The standard IEC 61850-7-420 defines logical nodes (LNs) suitable for this purpose but there are not yet available devices applying this part of the standard. Therefore in this research, a light-weight 61850 GOOSE based LoM solution has been developed and demonstrated applying a microcontroller and available open source software. This paper introduces object modeling according to IEC 61850-7-420 defined LNs and an implementation applying GOOSE messages and microcontroller. The validity of the light-weight implementation is demonstrated with a simple laboratory setup that has been used for measuring the message latencies.fi=vertaisarvioitu|en=peerReviewed

Implementing IEC 61850-7-420 DER Logical Nodes in a single board computer

En este artículo se presenta la implementación de una variedad de nodos lógicos (NLs) de sistemas de generación basados en recursos energéticos distribuidos (DER), en una placa electrónica (o SBC) que permite la adquisición y empaquetamiento de señales analógicas de un arreglo fotovoltaico con baterías, con base en el estándar IEC 61850-7-420. Para esto, se usa una placa electrónica SBC (Single Board Computer) integrada con una tarjeta de conversión análogo digital (ADC) que permite la lectura de los valores analógicos del sistema. La SBC se comunica con la tarjeta ADC para empaquetar los datos leídos dentro de los objetos de datos propios del estándar IEC 61850, usando el nodo lógico (NL) respectivo. Se usó una librería con licencia abierta para la creación del servidor IEC 61850 en la placa electrónica, y el driver del fabricante de la tarjeta ADC para comunicar las dos tarjetas efectivamente. Lo que se busca con este trabajo es el desarrollo de nodos lógicos (NLs) para recursos energéticos distribuidos (DER), de tal forma que los fabricantes de tecnologías de generación basadas en fuentes renovables, como la solar y/o la eólica, incorporen los equipos electrónicos inteligentes (IED) y los controladores de acuerdo con la extensión del estándar para estos nodos lógicos. Se presentan las pruebas de comunicación de la implementación realizada y los resultados obtenidos.This article discusses the implementation of a variety of logical nodes (LNs) of power generation systems based on distributed energy resources (DER) in a single board computer (SBC). The SBC allows for the acquisition and encapsulation of analog signals from a photovoltaic (PV) array with batteries, based on the IEC 61850-7-420 standard. To achieve this, an SBC integrated with an analog-digital conversion card (ADC) enables to read the system’s analog values. The SBC communicates with the ADC card to encapsulate the collected data in the IEC 61850 data object by using the corresponding logical node (LN). An open license library was used to create the IEC 61850 server inside the SBC and the driver of the ADC card manufacturer to communicate both cards. This work aims to develop LNs for DERs in such way that manufacturers of power generation technologies based on renewable sources (such as the sun and/or the wind) implement Intelligent Electronic Devices (IED) and controllers in accordance with the scope of the standard for these logical nodes (LNs). Finally, the communication testing of the implementation and the results obtained are presented

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