Thoughts on the Possibility of Damage of High-Voltage Electrical Insulation below the so-called Inception Voltage: The Historical Background – Part I
Partial discharges (PD) may cause damage to high-voltage (h.-v.) electrical insulation and eventually breakdown. It is known, however, that sudden breakdowns occurred in industrial insulations after only a few months in service, although they had passed the suggested international specifications tests. In this paper, we investigate the possibility of damage of an h.-v. insulation even below the inception voltage, giving the historical background which led to certain thoughts. References to previous work are given and a differential equation is proposed regarding the possibility of having charging phenomena below the inception voltage.