Evaluating the performance of decentralized analyses of voltage stability and power flows

Increasing complexity and uncertainty of power system operation have led to a rising interest in decentralized control concepts as a complement or alternative to centralized control. For decision-making on appropriate control actions, such approaches need to perform analyses of the system state and the estimated impact of control actions basing on limited system information. Thus, it has to be ensured that the decentralized analyses yield sufficiently accurate results and enable reliable control. The choice of valid indicators and estimates of control responses depends particularly on the required level of accuracy and the size of the observed area. This paper presents a methodology for evaluating the performance of decentralized analyses of voltage stability and power flows depending on the observability area. The results shall provide developers of decentralized concepts with insights on the suitability of different indicators, the trade-off between accuracy and the size of the observed area, as well as awareness of potential threats due to the use of incomplete data, possibly causing unstable and adverse control effects.