Partial Discharge Detection in Pressboards Immersed in Mineral Insulation Oil with Quantum Well Hall Effect Magnetic Field Sensors

Insulation degradation may cause inefficient and faulty operation of transformers. The insulation failures in transformers mostly start with a Partial Discharge (PD) event. For both operational and cost reasons to ensure the best performance and functionality of transformers, early detection of PD events is of great importance. In this paper presents a novel PD detection technique by using a highly sensitive Quantum Well Hall Effect (QWHE) magnetic field sensor and compare the findings with an off-the-shelf silicon magnetic field transducer. The investigation of the QWHE for high voltage engineering problem such as PD detection is given first time in this paper. The aim of the study is to detect PD activity in pressboards immersed in mineral insulation oil experimentally using a new QWHE sensor. The measured experimental data from both sensors are decomposed by Empirical Mode Decomposition (EMD) and Wavelet Decomposition (WD) methods, and PD signals are analyzed comparatively. The results show that QWHE sensors provide more accurate and noise free measurements allowing early and more accurate PD detections.