Faster and cheaper development of aircraft power equipment
Europe's aircraft industry has committed to revolutionising energy systems on board aircraft by gradually replacing bulky hydraulic and pneumatic systems with electric ones. As new electric power systems reach higher voltages, partial discharges become a significant issue especially at high altitudes and should be mitigated through careful design. Important design factors to reduce the likelihood of a partial discharge is proper spacing of components and insulation thickness. However, guidelines for evaluating the ability of insulation materials to remain resilient throughout their lifespan are lacking. To help determine how insulation materials can affect partial discharge, researchers within the EU-funded project PDMAN (Partial discharge management in compact insulation systems) conducted numerous tests on wound and connecting components using a variety of voltage waveforms. Components were subjected to accelerated ageing to help reveal under what electrical stress breakdown occurs and degrades performance of insulation materials. The data collected led to the draft of a set of useful guidelines on the design and qualification process of insulation systems used in aerospace applications. Additionally, researchers created a design tool that provides critical information on the quality of insulation and its impact on the component health. Allowing engineers to modify the properties of the insulation materials and monitor how changes affect partial discharge, it enables a more informed decision on insulation requirements for wound and connecting components at an early stage of design. In particular, the innovative decision-making tool helps determine safe clearances between uninsulated electrodes, the partial discharge inception voltage for wound and connecting components, and the minimum insulation thickness to prevent partial discharge. Project members also drafted a document detailing test procedures required to support equipment qualification and assessment during a series production of wound/connecting components. The proposed guidelines and the new tool developed by PDMAN should help reduce development time and cost of new electric power systems. The challenges associated with testing wound components for partial discharge in an aerospace environment were presented at the IEEE Electrical Insulation Conference in Seattle, Washington in 2015 and at a seminar that took place at Rolls Royce in the United Kingdom in the same year.
Keywords
Aircraft, electrical discharges, wound/connecting components, power systems, insulation, PDMAN