ERIGrid Holistic Test Description for Validating Cyber-Physical Energy Systems

Smart energy solutions aim to modify and optimise the operation of existing energy infrastructure. Such cyber-physical technology must be mature before deployment to the actual infrastructure, and competitive solutions will have to be compliant to standards still under development. Achieving this technology readiness and harmonisation requires reproducible experiments and appropriately realistic testing environments. Such testbeds for multi-domain cyber-physical experiments are complex in and of themselves. This work addresses a method for the scoping and design of experiments where both testbed and solution each require detailed expertise. This empirical work first revisited present test description approaches, developed a newdescription method for cyber-physical energy systems testing, and matured it by means of user involvement. The new Holistic Test Description (HTD) method facilitates the conception, deconstruction and reproduction of complex experimental designs in the domains of cyber-physical energy systems. This work develops the background and motivation, offers a guideline and examples to the proposed approach, and summarises experience from three years of its application.This work received funding in the European Community’s Horizon 2020 Program (H2020/2014–2020) under project “ERIGrid” (Grant Agreement No. 654113)

Assessment of flexibility in different ancillary services for the power system

To handle the changing power system and enable the energy transformation, several actions are needed, where the increase of digitalization, automation and more substantial production variability implies a need for flexibility. Solutions providing advances in flexibility are of importance for the future power system. The paper will contribute with knowledge that will support the diversified and efficient use of flexibility, making the electricity system more flexible and delivering the benefits for all system stakeholders. This will both be based on a review of definition and classification of flexibility, flexibility assessment solutions and example of how flexible resources can be utilized in different ancillary services. Different use cases have been developed showing how flexible resources can be utilized in different ancillary services, such as voltage control, management of bottlenecks in the distribution grid and balancing services. The use cases also include a description of the stakeholders involved. Index Terms: Flexibility, Congestion Management, Ancillary services, Voltage ControlacceptedVersio

Power hardware-in-the-loop validation of post-primary voltage control scheme

The concept and experimental validation process of the Web-of-Cells (WoC) based Post-Primary Voltage Control (PPVC) developed in EU FP7 project ELECTRA IRP is presented in this paper. The main objective of PPVC is to provide an optimal and local voltage control replacing the conventional secondary and tertiary voltage control. The Power Hardware-In-the-Loop (PHIL) setup and the experimental results comparing the PPVC approach to traditional voltage control techniques are presented and discussed. The PPVC has demonstrated lower number of tap-changes and faster response to topology changes. To avoid simulation overrun in real-time environment, a slower simulation step is adopted for the electrical network model than the converter and grid emulator controller models in the Simulink model. The PHIL test conducted gives insight to the potential obstacles that may arise with increased number of cells and increased number of nodes in the network. © Copyright 2017 IEEE - All rights reservedacceptedVersio

Assessment of flexibility in different ancillary services for the power system

To handle the changing power system and enable the energy transformation, several actions are needed, where the increase of digitalization, automation and more substantial production variability implies a need for flexibility. Solutions providing advances in flexibility are of importance for the future power system. The paper will contribute with knowledge that will support the diversified and efficient use of flexibility, making the electricity system more flexible and delivering the benefits for all system stakeholders. This will both be based on a review of definition and classification of flexibility, flexibility assessment solutions and example of how flexible resources can be utilized in different ancillary services. Different use cases have been developed showing how flexible resources can be utilized in different ancillary services, such as voltage control, management of bottlenecks in the distribution grid and balancing services. The use cases also include a description of the stakeholders involved. Index Terms: Flexibility, Congestion Management, Ancillary services, Voltage Contro

Assessment of flexibility in different ancillary services for the power system

To handle the changing power system and enable the energy transformation, several actions are needed, where the increase of digitalization, automation and more substantial production variability implies a need for flexibility. Solutions providing advances in flexibility are of importance for the future power system. The paper will contribute with knowledge that will support the diversified and efficient use of flexibility, making the electricity system more flexible and delivering the benefits for all system stakeholders. This will both be based on a review of definition and classification of flexibility, flexibility assessment solutions and example of how flexible resources can be utilized in different ancillary services. Different use cases have been developed showing how flexible resources can be utilized in different ancillary services, such as voltage control, management of bottlenecks in the distribution grid and balancing services. The use cases also include a description of the stakeholders involved. Index Terms: Flexibility, Congestion Management, Ancillary services, Voltage Contro

Assessment of flexibility in different ancillary services for the power system

To handle the changing power system and enable the energy transformation, several actions are needed, where the increase of digitalization, automation and more substantial production variability implies a need for flexibility. Solutions providing advances in flexibility are of importance for the future power system. The paper will contribute with knowledge that will support the diversified and efficient use of flexibility, making the electricity system more flexible and delivering the benefits for all system stakeholders. This will both be based on a review of definition and classification of flexibility, flexibility assessment solutions and example of how flexible resources can be utilized in different ancillary services. Different use cases have been developed showing how flexible resources can be utilized in different ancillary services, such as voltage control, management of bottlenecks in the distribution grid and balancing services. The use cases also include a description of the stakeholders involved. Index Terms: Flexibility, Congestion Management, Ancillary services, Voltage Contro

Assessment of flexibility in different ancillary services for the power system

To handle the changing power system and enable the energy transformation, several actions are needed, where the increase of digitalization, automation and more substantial production variability implies a need for flexibility. Solutions providing advances in flexibility are of importance for the future power system. The paper will contribute with knowledge that will support the diversified and efficient use of flexibility, making the electricity system more flexible and delivering the benefits for all system stakeholders. This will both be based on a review of definition and classification of flexibility, flexibility assessment solutions and example of how flexible resources can be utilized in different ancillary services. Different use cases have been developed showing how flexible resources can be utilized in different ancillary services, such as voltage control, management of bottlenecks in the distribution grid and balancing services. The use cases also include a description of the stakeholders involved. Index Terms: Flexibility, Congestion Management, Ancillary services, Voltage Contro

Post-primary voltage control using optimal power flow for loss minimization within web-of-cells concept

This paper presents the decentralized Post-Primary Voltage Control (PPVC) scheme which is introduced within the Web-of-Cells (WoC) concept in the ELECTRA IRP project. The PPVC improves the traditionally known secondary and tertiary voltage control schemes to develop a robust method coping with the emerging intermittent generation and variable loading in the distribution system. PPVC aims to utilize all available resources within a defined network area for voltage control purposes by taking loss minimization as an objective. To achieve that, the re-definition of voltage set-points in all controllable nodes within the area is performed using an Optimal Power Flow (OPF) algorithm. The proposed PPVC algorithm coordinates tap changers and other reactive power resources such as PV inverters proactively altering their settings for a recurring time-window. The settings are optimally computed by using short-term forecasted load and generation values. The PPVC algorithm has been implemented with MATLAB and the General Algebraic Modeling System (GAMS) tool for optimization and evaluated on The European CIGRÉ MV network, modified with distributed energy resources (DERs). Simulation results showing the impact of PPVC compared to the business-as-usual (BaU) way of voltage control are presented. In addition, laboratory tests coupling the GAMS-based OPF with OPAL-RT have been conducted to present the efficiency of PPVC in real-time applications.acceptedVersio

Design of Experiments aided Holistic Testing of Cyber-Physical Energy Systems

The complex and often safety-critical nature of cyber-physical energy systems makes validation a key challenge in facilitating the energy transition, especially when it comes to the testing on system level. Reliable and reproducible validation experiments can be guided by the concept of design of experiments, which is, however, so far not fully adopted by researchers. This paper suggests a structured guideline for design of experiments application within the holistic testing procedure suggested by the European ERIGrid project. In this paper, a general workflow as well as a practical example are provided with the aim to give domain experts a basic understanding of design of experiments compliant testing.</p