Emprego de um comutador eletrônico de taps para regulação de tensão em redes elétricas a partir do modelo de carga

Abstract

This doctoral thesis proposes a method for regulating the secondary voltage of distribution systems based on the identification of ZIP models of the load (constant impedance, constant current and constant power) at the interface of medium and low voltage distribution networks. The proposed method considers the variation of the secondary voltage within the appropriate limits established in current regulations and the identification of the behavior of the load against this variation, which allows the equipment that regulates the secondary voltage to operate according to pre-established objectives, such as: reduction of losses, load shedding, control over the billing of utility companies and on the injection of distributed generation. For this, the geometric analysis of normalized ZIP load models is proposed in this paper, which in a generalized fashion, describes the behavior of the load power and/or current for voltage variations based on the coefficients that compose the model. It should be noticed that the proposed method is applicable to any equipment that allows variation of the magnitude of the grid voltage. In this work, the proposed method is employed considering as voltage regulating agents the transformers which employ electronic on-load tap changers, which are equipped with a bidirectional communication system, allowing: the regulation of the secondary voltage, the grid monitoring, it also allows obtaining the load model at the point of installation of the equipment and the definition of the optimization goal of the grid that the equipment must prioritize. Throughout the work are presented analyzes regarding the geometric interpretation of standardized ZIP models, as well as the proposed method for regulation of secondary voltage, experimental results regarding the obtaining of load models from electronic tap changers and simulation results employing the voltage regulation method proposed in a standard 13-bus IEEE distribution network.