Evaluation von Synergieeffekten zentraler Speichersysteme in Niederspannungsnetzen durch integrative Modellbildung

Doctoral thesis (2022)

Security of supply, affordability, and sustainability form the pillars of a new energy policy towards renewable generation and decarbonization. However, the dynamics of the power generation due to the ... [more ▼]

Security of supply, affordability, and sustainability form the pillars of a new energy policy towards renewable generation and decarbonization. However, the dynamics of the power generation due to the increasing amount of renewable energies cause temporal and local discrepancies between generation and consumption. Resulting energy transports between grid sections and different voltage levels cause additional load flows. To ensure grid stability, the grid operator provides system services and grid extension measures. With the help of energy storage systems with grid-serving control and placement strategies, the flexibility of the electricity supply can be increased. Besides, a high amount of renewable energy can be used locally while maintaining grid stability. A centralized installation approach focussing single grid sections, instead of many decentralized home storage units, offers economic and environmental advantages. Furthermore, the operation strategy can be optimized by the global view of the grid operator and thus be adapted to local conditions. This research evaluates synergy effects of central storage systems by integrative computational analysis using a rural low-voltage grid section in Luxembourg. Three linked simulation levels are used to calculate operational strategies, storage dimensioning as well as placement based on 15-minute smart meter data. The operation strategy is developed within a power system simulation and is used to control a parameterizable simulation model of a vanadium-redox-flow-battery. The operating strategy focuses on reducing the maximum power flow at the transformer and reactive power compensation to maintain voltage stability. A future photovoltaic scenario is being adopted by doubling the status quo photovoltaic generation. The simultaneous optimization of storage utilization and power reduction at the transformer provides the storage design parameters power and capacity. Storage placement is determined by the system boundary and the resulting data selection. A final sensitivity analysis evaluates an optimized storage placement while enhancing the voltage profiles. The results of this work are a differentiated active as well as reactive power related operating strategy, automated calculation algorithms to determin control parameters, optimized battery design parameters as well as the methodical approach to transfer calculation algorithms to further grid sections. [less ▲]