Acoustic emission monitoring is often used in the diagnosis of electrical and mechanical incipient faults in high voltage
apparatus. Partial discharges are a major source of insulation failure in power transformers and the differentiation from
other sources of acoustic emissions is of the utmost importance. Also, it is important to give an indication of the PD
source location in order to obtain a useful diagnosis. This paper reports the developments in partial discharges source
location through the associated acoustic emissions using three different algorithms.
Partial discharges are a major source of insulation failure in electric power transformers. Their detection can be achieved
through the associated acoustic emissions, and this work reports on the investigation of a fibre laser sensor based on a
phase-shifted chirped fibre grating for acoustic emission detection in the power transformer environment. The
performance of the sensing head is characterized and compared for different surrounding media: air, water and oil.
Incipient fault diagnosis is closely related to insulation condition assessment. A great number of methods are available for condition monitoring and diagnosis of power transformer insulation systems, but only few of them can take direct measurements inside the transformer. Fiber optic sensors can be applied to incipient fault diagnosis. In particular, acoustic sensors have been developed for detection and location of partial discharges in oil-filled power transformers. We report the study of extrinsic and intrinsic fiber Fabry-Pérot sensors that can be used to detect the acoustic waves that are generated by a partial discharge inside a power transformer. A comparative analysis is done to determine the best sensing head configuration and some methods to improve the parameter readout sensitivity are proposed. The sensing head behaviour when immersed in different fluids (air, water, and oil) is also investigated.
Incipient fault diagnosis is closely related to isolation condition assessment. There are a great number of methods
available for condition monitoring and diagnosis of power transformer isolation systems, but only few of them can take
direct measurements inside the transformer. Fibre optic sensors can be applied to incipient fault diagnosis. In special,
acoustic sensors are being developed for the detection and location of partial discharges in oil-filled power transformers.
Towards such objective, this work reports investigation on the applicability of fibre Fabry-Pérot interferometers for
acoustic detection both in air and in liquids.