Filtro morfológico de extração de envoltória para proteção contra perda de excitação do gerador síncrono

Abstract

Most of the energy consumed in the world is produced by synchronous generators. The loss or failure of one of these machines can directly affect the electrical system, if it is not robust enough to supply the amount of generation lost in a short time. The robustness of the electric power system, plus the correct dimensioning of the components, depends on the protection system that monitors each device, ensuring continuity of electricity supplying. The protection is done by relays, which realize the system disruption based on the voltage and /or current signals. When a severe disturbance is detected, the relays must act in order to send a signal to open the circuit breaker, unplugging equipment or defective portion from the rest of the system. This work aims to propose a new technique for protection against loss of excitation (PE) of synchronous generators, based on a morphological filter to extract the envelopments of a waveform, which is able to differentiate stable power swings (OEP) from loss of field events. The new technique is based on the analysis of voltage and current signals at the generator terminals, and is effective, robust, fast and showing good accuracy and satisfactory performance on detecting power swings and loss of field, when compared to traditional methodologies.