@phdthesis{LorenzMeyer2024, author = {Lorenz-Meyer, Maximilian Nicolai Lorenz}, title = {State and parameter estimation approaches for online dynamic security assessment in power systems}, doi = {10.26127/BTUOpen-6911}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-69114}, school = {BTU Cottbus - Senftenberg}, year = {2024}, abstract = {With the global effort to decarbonize the energy sector, major changes are being implemented in power systems. This shift drastically alters the system dynamics, prompting the need for innovative online dynamic security assessment (DSA) tools. Such tools are crucial for system operators to gain situational awareness and make corrective or preventive operational decisions, ensuring reliable, secure, and cost-efficient system operation. A key component of online DSA tools is power system dynamic state estimation (DSE), used to obtain real-time estimates of critical system states and parameters, such as the inertia constant or the states and parameters of synchronous generators. Motivated by this, control theory-based approaches for DSE that focus on two key challenges are developed in the present thesis. Firstly, the topic of multi-area inertia estimation is addressed. Secondly, the problem of decentralized state and parameter estimation for synchronous generators is considered. Unlike much of the existing literature on the topic, rigorous analytical convergence guarantees are provided. More specifically, the main contributions of this work are as follows: 1) A robust tuning method for consensus + innovations-based distributed parameter estimation in the presence of disturbances is derived. This technique allows for systematic gain tuning, while providing guaranteed robustness properties and avoiding trial-and-error gain selection. As disturbances, such as measurement noise, perturbations in the communication channels, and model mismatches, arise in any real-world application, the tuning procedure can be utilized for various distributed estimation problems in the context of DSE and other fields. 2) The method presented under Item 1 is employed to develop a robust distributed inertia estimation approach for interconnected power systems. Differing from similar approaches, the proposed scheme requires only peer-to-peer communication of local parameter estimates between neighboring control areas, avoiding the need for a central entity with access to global measurement information. The performance of the approach is validated by simulations. 3) A decentralized unknown input scheme for reconstructing the states of synchronous generators in a multi-machine power system along with critical machine parameters is proposed. Only phasor measurements from a substation near a power plant are required for this. Such a location is more accessible to system operators than the generator's terminal bus, which is the usual measurement location assumed in the literature. Lastly, the performance is validated in a simulation study and using real-world measurement data from the German high-voltage grid.}, subject = {Online dynamic security assessment; Power grid monitoring; Dynamic state and parameter estimation; Robust distributed estimation; Dynamische Sicherheitsbewertung; Stromnetz{\"u}berwachung; Dynamische Zustands- und Parametersch{\"a}tzung; Robuste verteilte Sch{\"a}tzung; Regelungstheorie; Verbundnetz; Sicherheit; Bewertung; Synchrongenerator; Parametersch{\"a}tzung}, language = {en} }