ADDRESS FIBER OPTICAL SENSORFOR ACOUSTIC DETECTION OF A PARTIAL DISCHARGE IN A SWITCHGEAR
The paper presents a sensor for detecting a partial discharge in switchgear (SG) and discusses the prospects for its implementation using new technologies for building acoustic sensors on address fiber Bragg structures (AFBS). In an electrical system, a partial discharge (PD) is defined as a local electrical discharge that only partially breaks the insulation between conductors. PD provides an early indication of insulation damage, and therefore monitoring of the PD can be an important tool for assessing the state of any electrical equipment. Although PD measurement is mainly performed during the maintenance of high voltage equipment, continuous PD monitoring is becoming increasingly relevant. During production, operation, or maintenance, the surface of the conductors in SG may be humidified, contaminated, or even damaged. This will negatively affect the quality of the insulation, which can be subsequently detected by measuring the intensity and the number of PD. Recently, sensors based on fiber Bragg structures (FBS) have proven to be useful in various fields of science and technology. In this paper, we consider the FBS Bragg wavelength shift caused by the pulsed acoustic pressure generated during the PD in an airtight switchgear. It uses the address FBS, which, if there are several sensors installed in the SG, may indicate the zone of occurrence of the PD and its intensity, which are determined, unlike many known devices, in the microwave frequency domain. In addition, AFBS free from the influence of electrical and radio interference due to the optical nature of the sensor. The sensor was developed within the framework of the «Smart Grids Plus» concept for a diagnostic monitoring layer based on the passive fiber-optic sensor network of a hybrid structure with radio-photon signal processing.