Markus Kraiczy

BET Büro für Energiewirtschaft und technische Planung GmbH

The increased integration of variable renewable energy sources into the power grid can, amongst others, lead to fluctuations in voltage, which may result in issues like harmonics, flicker, unbalanced loads, and power oscillations. These factors can negatively impact power quality and the ability to transfer power effectively. Therefore, effectively...

Final Report of the MetPVNet Project.

Dieses Working Paper umfasst eine Kurzfassung des Abschlussberichtes, der im Rahmen des Forschungsprojektes "Entwicklung innovativer satellitengestützter Methoden zur verbesserten PV-Ertragsvorhersage auf verschiedenen Zeitskalen für Anwendungen auf Verteilnetzebene (MetPVNet)" verfasst wurde. Das Vorhaben MetPVNet wurde mit Mitteln des Bundesminis...

The PV penetration in many countries is continuously growing and PV is becoming a major energy source in the future electricity grid worldwide. Therefore, PV systems and PV hybrids need to take over more and more system responsibility by providing ancillary services. Ancillary service “means a service necessary for the operation of a transmission o...

The PV penetration in many countries is continuously growing and PV is becoming a major energy source in the future electricity grid worldwide. Therefore, PV systems and PV hybrids need to take over more and more system responsibility by providing ancillary services. The report highlights the status and the potential of PV and PV hybrids as an anci...

With the increasing penetration of distributed energy resources (DER) in power systems, the need for forecasts at the distribution level increases. In Germany, the upcoming redispatch 2.0 procedure will require DER forecasting and forecast-based congestion management at the distribution level. This paper evaluates the techno-economic benefits of ad...

The increasing penetration from intermittent renewable distributed energy resources in distribution grid brings along challenges in grid operation and planning. To evaluate the impact on the grid voltage profile, grid losses, and discrete actions from assets (e.g. transformer tap changes), quasi-static simulation is an appropriate method. Quasi-sta...

Due to higher penetration of renewable energy sources, grid reinforcements, and the utilization of local voltage control strategies, a significant change in the reactive power behavior as well as an increased demand for additional reactive power flexibility in the German power system can be predicted. In this paper, an application-oriented reactive...

New regulatory developments in the German energy sector, such as the introduction of the Redispatch 2.0 procedure or the discussion of market-based procurement procedures for reactive power, drive the need for grid operators to integrated forecasts of distributed generation in their operational planning procedures. In this paper, the benefits of ad...

Over the last two decades, grid-connecte d solar photovoltaic systems have increased from a niche market to one of the leading power generation capacity additions annually. In 2019 the total worldwide installed photovoltaic electricity generation capacity exceeded 630 GW. It is forecasted that 1 TW will be reached by 2022. This further development...

The study aims to develop practicable grid planning procedures for an advanced reactive power management at the transmission-distribution (T-D) interface by making use of controllable reactive power sources at the distribution level, like distributed energy resources (DER) and reactive power compensators. In Germany, also the high voltage level is...

Over the last two decades, grid-connected solar photovoltaic systems have increased from a niche market to one of the leading power generation capacity additions annually. In 2018 the total installed photovoltaic electricity generation capacity exceeded 500 GW. Another doubling is forecasted until the early 2020s. Therefore, the further development...

Many individual wind and solar integration studies have been conducted in the past. The integration studies have evolved towards looking at the integration of wind and solar at the same time. Integration studies typically simulate a future power system with wind and solar contributions (share or penetration) varying from 5% to more than 50% of annu...

This paper introduces a grid planning approach for reactive power management at the transmission-distribution interface with the support of distributed generators. The main research question is: can reactive power management with distributed generators provide controllable reactive power with a very high availability and can this reduce or avoid th...

In a power supply system with an increasing share of distributed generation, there is a growing need for generators and demand response units at the distribution level to support the operation of the bulk power system by providing ancillary services and/or market flexibility. PV systems are mainly connected to the distribution level and hence coord...

In the future more stringent requirements from transmission system operators (TSOs) on the reactive power exchange at grid interface of EHV-and HV level will lead to an increased necessity to control the reactive power flow within distribution grids. In addition, the change of reactive power behavior of distribution grids due to increasing penetrat...

A significant number of wind and solar integration studies have been conducted in recent years, and methodologies have evolved steadily. Since power system characteristics and data availability vary significantly, the results and methodologies used in these studies have varied accordingly. This article presents findings from an international collab...

The dramatic increase of PV generation implies several challenges in transmission and distribution system operation. As for transmission, major issues relate to the variability, uncertainty, reduction of inertia and regulation capabilities, with consequent higher needs in flexibility resources requirements. Flexibility is considered as the ability...

In this paper, latest results of the industrial project "Q-Study" are presented, which is carried out by "Fraunhofer IWES" together with the German distribution system operator "Bayernwerk Netz GmbH". The proposed project focuses on reactive power management in distribution systems using distributed generators and covers comprehensive research acti...

In recent years, the number of active grid components for voltage regulation in distribution grids has increased significantly. Besides voltage regulators (VRs), such as transformers with On Load Tap Changers (OLTCs), distributed generators can provide a certain voltage support by means of reactive power control (RPC). The different control entitie...

The Management Summary has been prepared by the IEA-PVPS Task 14 Subtask 2 leader Fraunhofer IWES (Germany) with valuable contributions from several IEA-PVPS Task 14 members and other international experts: Barry Mather (NREL, USA), Benoît Bletterie (AIT, Austria), Pieter Vingerhoets (KU Leuven, Belgium), Kenn Frederiksen (Kenergy, Denmark), Kazuhi...

Abstract— Grid integration studies try to assess the impact of future developments on large scale network areas, e.g. nationwide, state-wide or DSO-wide. Goals can be to support strategic alignment in the regulatory framework or to adapt the grid planning principles of DSOs. This paper presents pandapower, an open source software framework that was...

This paper presents recommendations for an effective commissioning and operation of distributed generators (DGs), focussing on the aspect of reactive power control for static voltage support. Error-sensitive tasks in the process chain from commissioning to operation are revealed, based on first-hand field experience of major German and Austrian dis...

Changing reactive power behaviors of distribution systems (e.g., due to higher degrees of cabling and local reactive power provision through distributed generators (DGs)) together with the loss of generator-based reactive power sources at transmission system level may lead to an increased demand of reactive power flexibilities in the distribution g...

Der Weg zu einem nachhaltigen, regenerativen Energieversorgungssystem bedeutet auch und gerade für die Verteilungsnetze einen tiefgreifenden strukturellen Wandlungsprozess. In Abb. 15.1 ist der Aufbau des elektrischen Versorgungssystems mit den einzelnen Netzebenen (NE) und der Anfang 2014 installierten Erzeugungsleistung der erneuerbaren Energien...

In this paper, the impact of voltage support by PV systems, installed at LV level, on the reactive power exchange at the HV/MV connection point is presented. The analysis was performed using a detailed system model of the smart grid re-gion Seebach (south-eastern Bavaria), encompassing LV and MV level. The simulations were performed for different v...

In dieser Veröffentlichung wird ein zentrales Regelungsverfahren vorgestellt, welches die Erfüllung von Blindleis-tungsvorgaben des Hochspannungsnetzbetreibers am 110 kV-Netzverknüpfungspunkt (NVP), mittels gesteuerter Blind-leistungsbereitstellung durch dezentrale Erzeugungsanlagen (DEA) in der Mittelspannungsebene ermöglicht. Das vor-geschlagene...

The massive deployment of grid-connected PV in recent years has brought PV penetration in the electricity grids to levels where the conventional fit-and-forget approach to interconnecting PV reaches its limits. In many cases, constraints and limitations of existing electricity infrastructure already have evolved to one of the key barriers delaying...

During the past four years, national experts from thirteen institutions around the world have worked together within the International Energy Agency (IEA) PVPS Task 14 Subtask 2 – High Penetration PV in Local Distribution Grids. The main aim of this collaboration was to identify industry’s best practices for achieving high penetration levels of PV...

First, we investigate the technical and economic potential of autonomously operating voltage control strategies in low voltage grids with high photovoltaic penetration. The investigated control strategies are based on the reactive power control capabilities of modern photovoltaic inverters and the application of distribution transformers with on-lo...

Im Verteilnetzbetrieb werden neben den Verteilnetztransformatoren zunehmend dezentrale Erzeuger, wie Photovoltaikanlagen, an der Spannungshaltung aktiv beteiligt. Zur Sicherstel-lung eines qualitativ hochwertigen Netzbetriebs sind ungewollte wechselseitige Beeinflus-sungen von PV-Anlagenregelung und Transformatorregelung auszuschließen bzw. auf ein...

In Niederspannungsnetzen mit hohem Anteil dezentraler Energieerzeugungsanlagen ist die Einhaltung des zulässigen Spannungsbands nach DIN EN 50160 eine der Hauptherausforderungen zur Sicherung einer zuverlässigen und qualitativ hochwerti-gen Energieversorgung. Auch Photovoltaikanlagen niedriger Leistungsklassen kön-nen durch Maßnahmen zur lokalen Sp...

A major issue for distribution system operators is to maintain voltage quality in their networks. This holds especially for networks with high local PV penetration. In times of high solar irradiation, reverse power flows can lead to voltage rises and violations of voltage limits at critical nodes. Inverter-based autonomous voltage control strategie...

ABSTRACT: Local reactive power provision by photovoltaic (PV) inverters can contribute to maintaining the voltage in distribution grids and therefore contribute to reduce grid reinforcement measures, caused by an increased PV penetration. This study investigates the interferences and dynamics of a parallel and autonomous operation of HV/MV on-load...

Technically effective and economically efficient voltage control is a major issue in distribution systems with high amounts of installed capacity from dispersed generators, such as photovoltaic. In this paper, the results of an encompassing cost–benefit analysis for different voltage control strategies are presented. The investigated voltage contro...

In diesem Beitrag wird untersucht, wie sich die lokale Spannungsregelung des Um-spannwerks-Transformators und die Blindleistungsregelung der Photovoltaikanlagen gegenseitig beeinflussen können. Es werden mögliche ungewollte Wechselwirkun-gen für den Netzbetrieb dargestellt. Für die Untersuchung wird ein spannungsebe-nen-übergreifendes Simulationsmo...

With the tremendous increase in installed capacity of renewable energy resources in Germany, distribution network operators are facing reverse power flows and voltage violations. Different control approaches for controllable network components and distributed energy units exist to maintain a secure and reliable grid operation. This conference contr...