Methodologies for a simultaneous estimation of power grid parameters and systematic measurement errors

SITZIA, CARLO

2024-02-09

---

Abstract

The thesis presents the development of methodologies for the simultaneous estimation of network parameters (lines and transformers) and compensation of systematic errors of instrument transformers. The estimation methodologies were developed in both single-phase and three-phase versions. Validation was carried out by means of different types of tests on IEEE standard networks, considering different operating conditions and uncertainty configurations. The results of the developed methodologies were compared with those obtained with some methods in the literature and always showed the best estimation results. Thus, the impact of the differences between the assumptions made regarding the measurement chain error and network models and actual behaviour was assessed. Once the possible impact was assessed, more generalized models of the measurement chain and network components were proposed and included in the estimation model. The thesis then addressed the validation of the proposed methodologies on grid emulators, evaluating the presence and impact of distributed generation plants or charging stations. The method also proved to be valid in these tests and, specifically, it was found that the presence of this type of technology can positively affect parameter estimation. In conclusion, the integration of the methodology was carried out on a fault localization algorithm found in the literature. In this context, it was assumed that for both parameter estimation and the fault localization algorithm, a measurement chain composed of protection transformers feeding P class PMUs was used. The method proved to be valid, in the presence of uncertainty in the network and measurement parameters, in reducing the error on fault location.