Assessment Of Partial Discharge And Breakdown Behaviour Of Components Exposed To High Voltage Gradients
Work Package Leader: Dr. Luca Lusuardi
Objectives
To analyze the impact of high voltage gradient on partial discharge and breakdown behavior of typical components used in the aerospace environment, and to identify methods for the verification and qualification of new insulation systems.
Description
This task will examine the impact of increasing slew rates on the partial discharge and breakdown behavior of typical components used in the aerospace environment (including the impact of varying pressure, humidity and temperature).
It will include an elaboration on the performance of electrical insulation materials typically used in power electronic systems as a function of rise time and switching frequency of the power converters.
The applicants and the TM will decide together which materials and samples will be subjected to investigation. The list of materials may comprehend samples of currently used materials and materials, not already certified for aerospace applications, but that are likely to be used.
The behavior of the partial discharge inception voltage (PDIV) as a function of voltage gradient, frequency and ambient pressure will be investigated. A model, that considers the dependence of PDIV on voltage gradient, temperature and atmospheric pressure will be investigated and validated through experiments carried out in a controlled environment using a variety of detectors as photon-counters, photomultipliers, antennas and, if feasible, conventional techniques based on conducted current pulses.
The aim of the task is to derive guidelines to (a) prevent PD inception when the aircraft is cruising at high altitudes and (b) understand the voltage to apply during quality tests carried out on complete stators at the ground level.
The task will identify tests/methods for the verification and qualification of new insulation systems.
A suitable test program will be individuated to examine the performance of insulation systems in electrical machines and connecting cables / connectors.
The task will identify the insulation types best suited to manage high voltage gradients and ideally capable of delivering partial discharge-free components. The task will also identify lacks in the verification and qualification standards and propose modifications for defining new methods for the verification and qualification of new insulation systems.