Modeling and Experimental Verification of Ultrasound Transmission in Electro Insulation Oil

Abstract

A verification study of ultrasound transmission numerical simulation results with experiment results is presented in this paper. The work considers a model of a transformer tank which is filled with electro insulating oil. In the experiment, performed under laboratory conditions, an ultrasound wave is generated by a piezoelectric transducer that is fixed in the centre of the tank and measured by another transducer mounted inside the tank at three distances: 10, 20 and 30 cm from the sound source. The transducer is able to measure and generate acoustic waves in the ultrasound frequency band up to 1 MHz. The simulation considers numerical calculation of acoustic pressure distribution inside the tank in which acoustic source emits waves with frequency equal to 100 kHz. Verification analysis has confirmed consistency of the numerically calculated values with the measurement results.

Solving a Set of Spherical Equations for Localization of Partial Discharges by Acoustic Emission Method

“…On the opposite sides of the tank three piezoelectric transducers were mounted. The AE signal measured was transferred through lters and ampliers circuit and was registered by a measuring card to which also the signal from the Rogowski coil was attached for triggering [13]. During tests, the Rogowski coil will serve as a measurement card trigger, when installed directly on the supply lines or bushings of electric power transformers that in normal operation are at high potential, which in adverse conditions can cause damage to the measurement path.…”

“…Signals a), b), c) and e), f), g) were registered with the three transducers, signals d) and h) are measured by the Rogowski coil [3]. transformer tank and also the metrological conditions and numerical procedures are presented in papers [13].…”

“…Based on the Gauss elimination method an algorithm was implemented and the equation set (41) was solved [13].…”

“…For solution of this problem electric signals which occur by PD and are measured by the Rogowski coil have been applied. Detailed explanation of this problem is presented in [13]. In this paper we concentrate just on solution and presentation of the spherical equations.…”

Mathematical model of optical signals emitted by electrical discharges occuring in electroinsulating oil

“…The independent variable was the wavelength component. The model was based on a literature review [20,21].…”