Calços elásticos para atenuação do ruído em transformadores elétricos a seco

Abstract

Dry-type electrical transformers are widely used due to their efficiency and safety; however, one of the challenges associated with their operation is the noise emission caused by mechanical vibrations, which can affect both acoustic comfort and the structural integrity of the equipment. These vibrations mainly result from electromagnetic forces acting on the core and windings, propagating through the mounting structures. To address this issue, the use of elastic pads has been studied as an effective solution for vibration attenuation and, consequently, noise reduction. Given this context, the main objective of this work is to analyze the effectiveness of using elastic pads in attenuating vibrations and thus reducing the noise emitted by dry-type transformers. The methodology adopted included a literature review, technical analysis of vibration generation and transmission mechanisms, a study of the properties of elastomeric materials used in pads, and the physical-mechanical sizing of these elements based on the operational parameters of a 150 kVA three-phase transformer. The study also included the three-dimensional modeling of the pads and their integration into the transformer's structure, as well as the development of a preventive maintenance plan with practical guidelines for the inspection, replacement, and performance monitoring of the elastic pads over time. The results showed that elastic pads are effective in reducing noise levels by up to 10 dB, depending on the type of material used and the quality of the installation. This reduction is perceptible to the human ear and represents a significant improvement in terms of acoustic comfort and structural preservation. Additionally, the study highlighted that scheduled replacement of the pads, combined with continuous monitoring of vibrations and noise, is essential to ensure the long- term effectiveness of the damping system. It is concluded that the use of elastic pads is a technically viable, cost-effective, and highly efficient solution for noise mitigation in dry-type transformers, providing both operational and environmental benefits. The adoption of this technology contributes to the sustainability of electrical systems by reducing the need for acoustic barriers, improving the work environment, and extending the service life of transformers. The implementation of preventive maintenance practices, as proposed in this study, ensures the continuous performance of these elements and strengthens the long-term reliability of the equipment.