Survey of De-noising Techniques for Partial Discharge Interferences

Partial Discharges (PD) are recognized as one of the main causes of degradation of internal insulation of power equipment and its subsequent failure in high voltage equipment. In most real-time applications such as extruded cables, Gas Insulated Substations (GIS) etc., polymeric insulation systems which invariably used. It is necessary and demand to detect even very low levels of PD pulse discharge and it becomes imperative that improved PD measurement systems capable of accurately detecting and acquiring pulse are utilized for diagnosis. Hence, from the perspective of practical onsite PD measurement and analysis, several non-conventional PD detections and measurement techniques are increasing being utilized. It necessitates meaningful measures to ensure appropriate noise detection and its removal. Detection and analysis of PD signals are significantly influenced by a variety of sources of noise during on-site measurement. Different types of noise interferences affect the measurement of PD signals which includes discrete spectral interference, repetitive pulses from power electronics components, amplifier noises etc. This research survey presents an overview of the state of the art of various PD detection and de-noising in detailed perspective and insight into the various PD detection and measurement techniques. Also, this paper presents the appropriate methods to extract the PD pulses from various types of noises. In addition, a substantially exhaustive compendium of findings reported by several researchers has been carried out and a comprehensive summary of various types of noises and interference signals during measurement of PD including specific benefits and limitations of various de-noising methods to extract PD pulses from noisy data are discussed in this research survey.