Trap creation of solid dielectric in high field

A three-step experimental method is developed to evaluate trap creation. In test results on PET and PP (polypropylene) films, it is shown that the trap creation rate is proportional to the time of field application while the field is constant and is enhanced exponentially with the applied electrical strength. By introducing the trap creation coefficient and assuming trap density increased to a certain value as the critical condition of electrical breakdown, it is deduced that the lifetime of the dielectric under high electrical strength (E>1 MV/cm) decreases exponentially with the increase of electrical field, which is consistent with the test results