Integration of a superconducting magnetic energy storage into a control reserve

To ensure the stability of the power system, the transmission system operators (TSOs) keep a control reserve in readiness. This standby capacity is activated when the power system comes under strain and is typically provided by conventional fossil fuel-fired power plants. With the transition from fossil fuel-based energy production to sustainable renewable energy, the process of maintaining the stability of the grid is becoming more complex. A superconducting magnetic energy storage (SMES) is an efficient and highly dynamic system, which can be integrated into a control reserve. The use of a 40 MW/25 MWh SMES in primary control is simulated, its functionality shown, and the results discussed in this paper. The reserve market is analysed for estimating the cost-effectiveness of the approach. The grid frequency indicates the requirements for the SMES. In order to meet the demands for the prequalification of the TSO, such a storage system has to be pooled together with other providers of balancing energy or has to be collateralized by technical units which are already prequalified. High requirements are made on the power converter. To control the thyristors, a sequence control is used to decrease the reactive power.