Acoustic emission signals associated with prebreakdown state in air high voltage insulating systems

The paper presents the method of acoustic emission (AE) in the study of the state of insulation systems with air as the high-voltage insulation. The tested object was a planar system of electrodes made of aluminum. In addition, the analysis of AE signals and the impact on these signals the presence of dielectric coating on the electrode surfaces of aluminum was tested. We examined the influence of saturation (seal) these coatings on the dielectric strength of the insulation system. The study was conducted at an air pressure values 1·105, 3·105 and 5·105 Pa. The strength of the electrical systems were tested at alternating voltage with a frequency of 50 Hz. Noted pros and cons of using the method of EA in the context of the assessment of high-voltage electric insulation devices. The presented results confirm the possibility of using acoustic emission method, not only for identifying vulnerable areas, but also to predict the time of of further use of high voltage device.