Experimental verification of the sparse design of a square partial discharge acoustic emission array sensor

This study experimentally verified the sparse design of a square partial discharge (PD) acoustic emission array sensor proposed in Xie et al (2014 Meas. Sci. Technol. 25 035102). Firstly, this study developed a square PD acoustic emission array sensor and determined the material, centre frequency, thickness, radius, etc of the element of this array sensor through analysis and comparison with others. Moreover, in combination with a sound-absorbing backing and a matching layer, a single acoustic emission array sensor element was designed, which laid the basis for the experimental verification of the ensuing sparse design. On this basis, the assembly of the square acoustic emission array sensor was designed. It realised the plug-and-play ability of the array elements and formed the basis for the experimental study of the following sparse design. Subsequently, this study established and introduced an experimental system and methods for PD positioning. Finally, it experimentally investigated the sparse design of a square PD acoustic emission array sensor. The 9-element square PD acoustic emission array sensor was used as an example to study the positioning effects on PD using the acoustic emission array sensor in optimum and random sparse structures respectively. The results suggested that: (1) the PD acoustic emission array sensor and corresponding experimental system were effective in detecting and positioning the PD; (2) the square PD acoustic emission array sensor proposed in Xie et al (2014 Meas. Sci. Technol. 25 035102) was feasible. Using this array sensor, it was possible to optimise the sparse distribution structure of this acoustic emission array sensor.