Surface potential decay of DC-corona-charged PET films on humid electrodes

• Published in: Journal of electrostatics Vol. 78; pp. 17 - 21
• Main Authors: Rouagdia, Karim, Nemamcha, Mohamed, Herous, Lazhar, Dascalescu, Lucian, Mellouki, Hamza
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2015
• Subjects: Corona-charging; Humid electrodes; Polyethylene terephthalate film; Surface potential decay (SPD); Polyethylene terephthalate film; Humid electrodes; Corona-charging; Surface potential decay (SPD)
• ISSN: 0304-3886; 1873-5738
• DOI: 10.1016/j.elstat.2015.09.004

Surface potential decay measurement is a widely used tool to test the electrical properties of insulation materials. The aim of the present paper is to evaluate the effect of a humid electrode on the surface potential decay process. The experiments are performed on 1-mm thick samples of PET films (50 mm × 50 mm) in ambient air (temperature: 25 °C–29 °C; relative humidity: 42%–48%). The samples are placed on a grounded humid electrode (aluminum plate covered by a humid textile: 52 mm × 52 mm), and are charged by exposing them for 10 s to the negative DC corona discharge generated by a high-voltage wire-type dual electrode. The results show that the humid electrode has a significant influence on the surface potential evolution during the first moments after corona charging. Bipolar charge injection is the main physical mechanism that explains this potential decay. •Aim: evaluate the effect of humid electrode on surface potential decay of PET films.•Experiments performed on 1-mm thick samples of PET films in ambient air.•Samples placed on a grounded humid electrode and charged by negative DC corona.•The humid electrode influences surface potential evolution after corona charging.•Charge injection is the main physical mechanism that explains this potential decay.