A Study of Partial Discharge in High Voltage DC Distribution Systems for Hybrid Electric Aircraft

摘要

The electric drive train of +1 MW hybrid electric propulsion systems will need to operate at high voltages (+1000 V) in order to manage the weight of the electric distribution feeders and components. The initiation voltage for partial discharge (PD), which causes damage over time decreasing life, and arcing, which can lead to instantaneous failure, is significantly reduced at the operating altitudes of commercial aircraft. Thus, current design practices, developed mainly through testing experience, limit operation to 230 VAC to prevent PC and arc. The current research is developing a general approach for first predicting the electric field in high voltage hardware, which when coupled with a model for predicting PD inception voltage as a function of altitude will provide an analytical method for determining if PD will occur. This is the first step in developing a design system for designing distribution hardware to operate at high voltage without incurring PD. Cable systems provide the concrete application for this general approach.