The partial discharge aging of polyethylene terephthalate (PET) foil with permanent surface discharge stress is investigated using different harmonic distorted voltage waveforms. Distorted voltage waveforms alter the partial
discharge behavior of insulation arrangements by affecting characteristics such as the apparent charge and repetition rate. Consequentially, an influence of the harmonic distorted voltages on the partial discharge aging of insulation materials is expected. The goal of this contribution is to identify the influence of the different harmonic voltage waveforms on the lifetime of the PET foil when constantly exposed to surface discharges.