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Green smart factories will be one of the key elements of the future smart grids. They will play an active role in managing the volatility of power generated by renewable energy sources (RES). In order to do that, the green smart factories must set up energy management systems to control the production processes according to both the on-site power generation by RES and external signals sent by the system operators. The aim of the study is to size energy storage systems and production buffer stocks as the flexibility options, allowing the highest integration of power generated by volatile energy within a manufacturing system. The concept of the net zero energy factory is considered. Algorithms for coordinating the flexibility options optimally have been developed. These algorithms are based on mixed-integer linear programming and aim to maximize the matching between RES power generation and flexible demand. A case study is used to verify the framework results. Key performance indices, such as the system self-sufficiency index and the system self-consumption index have been considered for evaluating the solutions developed. Finally, sensitivity analysis has been performed to assess the robustness of the solutions found.

The power system is changing towards a decarbonized one. The Kyoto protocol and the Paris climate agreement have prompted many nations to approve energy policies based on volatile renewable energy sources (RESs). However, the integration into the grid of the power generated by RESs as well as the electrification of the heating, gas and transportation sectors is becoming a huge challenge. Planning industrial and tertiary sites as net-zero energy systems (NZESs) might contribute to advance the solutions of fully integrating volatile RESs into the power system. This study aims to point out the importance of planning large energy consumer sites such as NZESs, and to depict a holistic modeling approach for this. The methodology is based on a multi-layer approach, which focuses on on-site power generation by RESs, on the improvement of energy efficiency, and on the increase of system flexibility. A qualitative case study has been conducted. It considers the planning of a Net-Zero Energy Data Center located in Germany. Results point out that new interdisciplinary and in particular social analysis methods are necessary. They might be used for accelerating the decision making process during the planning of RES-based on-site power generation systems. Besides, for computation and cooling systems, new technologies that are continuously emerging in the market should be taken into account. If well designed, they contribute to significantly decrease the whole energy demand of data center. Finally, optimal sizing of energy storage systems (electric and thermal) as well as an expedient choice of performance indicators to evaluate technology options are identified as the key factor for decreasing the external energy demand of tertiary sites, such as data center.

As real-time applications in information technology (IT) and operational technology (OT) advance, new innovative concepts become possible. IT/OT convergence opens new pathways to design and operate intelligent cyber-physical systems, such as the Digital Twin (DT) concept, which has been discovered as key technology by several industries. This paper describes how centralized and decentralized DTs can help to monitor and control future power systems with special consideration of their interaction in case of corrupted communication from cyber-attacks. While the virtual representation of substations is regarded from the edge computing perspective the control room of the interconnected power system represents the centralized perspective. The concepts allows to have a system wide perspective, while also keeping detailed information at hand. The future system operator in the control room will benefit from services provided by DTs analytical and control features, rising resilience to cyber-physical anomalies and enhance situational awareness.

This paper provides an introductory, mostly nontechnical exposition of recent Deep Learning concepts, as relevant to NATO information processing requirements. A baseline case of learning confidentiality classification rules for NATO documents is described, originally performed by applying classical machine learning methods. In the course of the investigation described in this paper, the classical approaches have been complemented by Deep Learning experiments. These experiments shed some light on the potential advantages of using Deep Learning approaches for NATO document processing and beyond.

Automatic load shedding is the ultimate countermeasure against imbalance in a power system and can effectively help preventing large blackouts. Taking into account a high penetration of renewable energy sources (RES) in the distribution grid, a clear distinction between load and generation at the PCC becomes increasingly more difficult. For that reason an adaptation of frequency relay parameters and their locations of installation are necessary. In Europe this is rest on a multi-step plan based on values such as the yearly peak load. In this paper a novel probabilistic method for automatic load shedding is presented that uses the average values instead of peak values for load shedding. Its applicability is verified by a dynamic power system model that was developed to compare the classical and novel probabilistic load shedding principle. The method is verified using data from a German TSO.

The use of Demand Side Integration (DSI) makes it possible to control electricity consumption and, at the same time, allows for different ancillary system (e.g. voltage and frequency control) or market services (e.g. load shifting) to be provided. In light of today’s power system, which is faced with a high penetration of renewable energy (more than 20%), DSI has become even more important. These new power systems make it especially necessary to shift plenty of demand to times of high feed-in from wind and solar power plants in order to avoid wasting green energy. Additionally providing ancillary services using DSI can help balancing the system. This paper is focused on the analysis of load shifting potential in the residential and commercial sectors. Therefore a scenario based procedure was developed and applied. It uses a genetic algorithm to consider the time-dependent behavior of the different loads, which are modeled as load blocks. The investigation was conducted in the scope of a VDE/ETG working group in close cooperation with industrial partners. The results determined a practical shifting potential for the investigated sectors (residential and commercial) in Germany which could reach 8 GW in 2030.

The combination of scanning probe microscopy and Raman spectroscopy enables chemical characterization of surfaces at highest spatial resolution. This so-called tip-enhanced Raman scattering (TERS) can be employed for a variety of samples where a label-free characterization or identification of constituents on the nanometer scale is pursued. Present TERS setup geometries are always a compromise for specific dedicated applications and show different advantages and disadvantages: Transmission back-reflection setups, when using immersion objectives with a high numerical aperture, intrinsically provide the highest collection efficiency but cannot be applied for opaque samples. Those samples demand upright setups, at the cost of lower collection efficiency, even though very efficient systems using a parabolic mirror for illumination and collection have been demonstrated. In this contribution it is demonstrated that the incorporation of a dichroic mirror to a transmission TERS setup provides easy access to opaque samples without further modification of the setup.

This paper presents the system design and the first practical experiences of a Distribution Area Monitoring System (DAMS) that was practically applied in the German 110 kV network. With regard to the involved components of the larger ICT system, the software architecture - including standardized Smart Grid communication protocols and interfaces - is described. As a main component, a linear state estimator is presented, that uses only phasor measurements to calculate the complex-valued node voltages. Real measurement data provides the necessary input for observing the typical characteristics in distribution systems and for analyzing accuracy and plausibility of the results. A consecutive state assessment is applied in order detect violations of permissible operation limits.

Coordination of ancillary services provided by decentralized power units has become one of the main grid operation challenges because system service responsibilities are increasingly being shifted to medium- and low-voltage networks. This paper describes an implementation method of considered control algorithms on real power units in German mediumvoltage systems in order to maintain the distribution node voltages within the allowable range. The algorithms adjust active as well as reactive power set points, taking into account sensitivity matrices of critical nodes to ensure voltage stability at any time and in any system state. The remote control of the considered electrical system is designed according to the approved smart grid communication standards. Taking into account the electrical limitations of the considered power units selected cases are validated by load flow calculations in order to demonstrate the technical feasibility of the algorithms and their supporting effect on the distribution grid.

The number of high voltage direct current transmission (HVDC) installations is growing rapidly nowadays, and network operators are working to define grid codes that regulate behaviors of HVDC system to operate under different conditions. This paper presents implementation of a small-scale HVDC lab prototype, which aims at studying the characteristics of the VSC-HVDC system and meeting the requirements of grid code. Some key requirements in grid code are analyzed. Control strategies and design considerations to meet these requirements are presented in this paper. Finally, the validity of the design and the control strategies is verified by simulation and experimental results.

HVDC-Technology is assuming ever greater importance in the transmission of electric power. This requires development of equipment that takes highly precise and time synchronized measurements in DC systems. The data acquisition, the data transfer and a standardized communication interface are important factors to fulfill the requirements for secure and safe power system operation. This paper describes the development of one such system for HVDC measurement with communications interfaces compliant with IEC 61850. Taking the system modeling as the starting point, the finished measurement system and some initial results of the equipment's operation are presented.

This paper presents design and control of a small-scale high voltage direct current transmission (HVDC) lab prototype, which is intended to study the characteristics of the HVDC system and develop strategies to coordinate the operation of offshore wind systems with the network. At first, the configuration of the whole HVDC system is explained. The structure, the scaling approach, the DC cable model and central control user-interface are presented. Then the control strategies and selection of main circuit parameters are discussed. Finally, the validity of the design is verified by simulation and experimental results.