Georgios Anagnostou | Imperial College London (original) (raw)
Uploads
Papers by Georgios Anagnostou
IEEE Transactions on Power Systems
This paper proposes a decentralized derivative-free dynamic state estimation method in the contex... more This paper proposes a decentralized derivative-free dynamic state estimation method in the context of a power system with unknown inputs, to address cases when system linearisation is cumbersome or impossible. The suggested algorithm tackles situations when several inputs, such as the excitation voltage, are characterized by uncertainty in terms of their status. The technique engages one generation unit only and its associated measurements, and it remains totally independent of other system wide measurements and parameters, facilitating in this way the applicability of this process on a decentralized basis. The robustness of the method is validated against different contingencies. The impact of parameter errors, process and measurement noise on the unknown input estimation performance is discussed. This understanding is further supported through detailed studies in a realistic power system model. Measured stator current magnitude K Kalman gain matrix k kth time step
In electric grids with large photovoltaic (PV) integration, the PV system dynamics triggered by i... more In electric grids with large photovoltaic (PV) integration, the PV system dynamics triggered by irradiance variation is an important factor for the power system stability. Although there are models in the literature that describe these dynamics, they are usually formulated as block diagrams or flowcharts and employ implicit equations for the PV generator, thus requiring application-specific software and iterative solution algorithms. Alternatively, to provide a rigorous mathematical formulation, a state-space representation of the PV system dynamics driven by irradiance variation is presented in this paper. This is the first PV dynamic model in entirely state-space form that incorporates the maximum power point tracking (MPPT) function. To this end, the Lambert W function is used to express the PV generator's equations in explicit form. Simulations are performed in MATLAB/Simulink to evaluate and compare the proposed dynamic model over the detailed switching modeling approach in terms of accuracy and computational performance.
IEEE Transactions on Power Systems
This paper proposes a decentralized derivative-free dynamic state estimation method in the contex... more This paper proposes a decentralized derivative-free dynamic state estimation method in the context of a power system with unknown inputs, to address cases when system linearisation is cumbersome or impossible. The suggested algorithm tackles situations when several inputs, such as the excitation voltage, are characterized by uncertainty in terms of their status. The technique engages one generation unit only and its associated measurements, and it remains totally independent of other system wide measurements and parameters, facilitating in this way the applicability of this process on a decentralized basis. The robustness of the method is validated against different contingencies. The impact of parameter errors, process and measurement noise on the unknown input estimation performance is discussed. This understanding is further supported through detailed studies in a realistic power system model. Measured stator current magnitude K Kalman gain matrix k kth time step
In electric grids with large photovoltaic (PV) integration, the PV system dynamics triggered by i... more In electric grids with large photovoltaic (PV) integration, the PV system dynamics triggered by irradiance variation is an important factor for the power system stability. Although there are models in the literature that describe these dynamics, they are usually formulated as block diagrams or flowcharts and employ implicit equations for the PV generator, thus requiring application-specific software and iterative solution algorithms. Alternatively, to provide a rigorous mathematical formulation, a state-space representation of the PV system dynamics driven by irradiance variation is presented in this paper. This is the first PV dynamic model in entirely state-space form that incorporates the maximum power point tracking (MPPT) function. To this end, the Lambert W function is used to express the PV generator's equations in explicit form. Simulations are performed in MATLAB/Simulink to evaluate and compare the proposed dynamic model over the detailed switching modeling approach in terms of accuracy and computational performance.