Aging of Insulation Materials under Repetitive Impulse Voltage Stress with high dv/dt

Inhalt:
Repetitive Impulse voltages with high frequencies and high dv/dt are leading to faster aging of insulation materials. This paper presents the testing equipment, the procedures, and the test results for two different materials: a typical wire insu- lation and a FR4-PCB material. The tests were performed under application conditions with wire-twists and PCB board samples under real geometric and environmental conditions. For the tests a special generator was developed which can handle up to 4 kV steep-voltage-impulses. Accelerated lifetime tests have been performed and the degradation and break-down mechanisms were analyzed with micro-structural investigation methods. The results of this research are limited to a small number of materials, but the developed test generator and methods are generally applicable and thus can be applied for consecutive investigations with different materials.