Estudo da aplicação conjunta de reator a núcleo saturado e capacitor chaveado a tiristor como solução para tensão em regime permanente de rede de distribuição.

Abstract

This study addresses the operational challenges in the electrical energy distribution network resulting from the expansion of distributed generation and electromobility. The objective consists in modeling, analyzing, and mitigating long-duration voltage variations, focusing on the phenomena of daytime overvoltage and nighttime undervoltage. To conduct the research, a computational modeling methodology is adopted within the Matlab/Simulink environment. The IEEE fourteen-bus test system is used as a base, adapted for a voltage of thirteen thousand eight hundred volts, focusing on a peripheral busbar. The method is divided into the calibration of a disturbance scenario without compensation and the subsequent implementation of two mitigating technologies: a twelve-pulse configuration saturated-core reactor and a thyristor-switched capacitor. The modeling parameters are based on standard short-circuit criteria from Brazilian utilities and on quality limits stipulated by the national regulatory agency. The results obtained in the base system validate the severity of the disturbances, recording a critical overvoltage due to photovoltaic solar injection and a critical sag resulting from electric vehicle charging. With the insertion of the mitigating systems, the reactor drains the excess of reactives and limits the overvoltage to the regulatory ceiling. The spectral analysis confirms the cancellation of lower-order harmonics, restricting distortions to the eleventh and thirteenth orders. In the nighttime scenario, the switched capacitor compensates for the reactive demand and restores the voltage in less than one cycle after activation, mitigating transients through synchronous triggering strategies. It is concluded that the joint operation between the magnetic control of the reactor and the electronic flexibility of the switched capacitor constitutes an integrated, robust, and efficient solution. As future perspectives, the development of passive filters for residual harmonics and the application of predictive control algorithms or fuzzy logic are pointed out for real-time adaptation to electromobility behavior.