Resumen de Data recovery algorithm in space charge measurement by PEA method
Zhengyi Han, George Chen, Junsheng Cao, Zhiyuan He, Haitian Wang, Wenpeng Li
Purpose – The pulsed electro-acoustic method is widely applied for space charge measurement in solid dielectrics. The signals, however, can be seriously distorted during transmission, especially in non-planar specimens. The purpose of this paper is to find an efficient algorithm to correctly recover the space charge profile for different types of specimens.
Design/methodology/approach – The distortion can be associated with both geometry and material (attenuation and dispersion). Hence the recovery algorithm consists of two parts, respectively. The influences of geometries, causing the divergences of electric force and acoustic waveform, can be corrected by sets of factors. The attenuation and dispersion of the material can be suppressed based on the transfer function matrix in frequency domain, which could be obtained from calibration.
Findings – A general algorithm applicable to three kinds of specimens (single-layer, multi-layer and coaxial-geometry dielectrics) has been proposed. Compared with the other two algorithms in literature, the present one offers the most accurate solution while taking relatively shorter time. In addition, this algorithm is applied on signals measured from a planar low-density polyethylene sample and the results show that the new algorithm is fairly effective with excellent stability in a real system.
Originality/value – As one of the most accurate algorithms, the present one is theoretically one-third quicker than the others. This algorithm would be helpful in applications calling for large calculations, i.e. 3D imaging of space charge distribution in XLPE cable.
