Two-dimensional Space Charge Measurement of Scaled Cable Joint Model

Feasibility of Space Charge Measurements on HVDC Cable Joints: Study Group—IEEE DEIS Technical Committee “HVDC Cable and Systems:”

“…Cable accessories, especially cable joints, have become the biggest weak link of the whole cable system, so it is particularly important to detect their health status through space charge detection techniques. At present, research [44,45,49] has improved the PEA detection system towards miniaturization of the pulse generation circuitry [44], which can greatly improve the practicability of the PEA detection system. The key parameters of cable insulation charge transport can be obtained through space charge detection system, and the change of internal charge transport state of insulation can be analyzed.…”

“…Another development affects the length of the measured cable, TSM can provide measurements over 50 cm of cable length by using OCT/OHT or on a full cable length by using IHT [47], whereas PEA with single sensor can be only applied on a thin layer of the cable in the range of cm depending on the acoustic sensor diameter [48]. In [49,50], PEA was used for measuring SC in a thick joint using a 2D multichannel sensor array to scan the longitudinal SC distribution in a length comparable to that of TSM. In [51], authors proposed a numerical model for calibration and interpretation of PEA measurement signals without applying a deconvolution algorithm.…”

“…As a result, most of the signal received by the acoustic sensor propagates into the backing material. Recent developments at Toyohashi University of Technology [49] have shown that a significant increase in the signal detected by the sensor can be obtained by using a polymeric acoustic coupler such as PMMA or Polystyrene. Thus, a good acoustic matching between the joint, the acoustic coupler and the PVDF sensor is obtained.…”

“…The TSM probe could be applied to different sections of the cable joints by utilizing a shield break joint and the current measuring electrode. The PEA cell cost and sized could be significantly reduced by taking advantage of the acoustic sensor line set up proposed in [44,45,49] where the HV pulse amplitude can be minimized together with the size of the PEA cell. In [49] is also shown that PEA sensors potentially could be installed in multiple locations.…”

“…The PEA cell cost and sized could be significantly reduced by taking advantage of the acoustic sensor line set up proposed in [44,45,49] where the HV pulse amplitude can be minimized together with the size of the PEA cell. In [49] is also shown that PEA sensors potentially could be installed in multiple locations. The study group in the future would be focusing on the practical aspects of the application of the HV pulse and the thermal shock for the PEA and TSM techniques respectively.…”