Non-Intrusive Partial Discharges Investigations on Aeronautic Motors

Abstract

OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. This is an author-deposited version published in : http://oatao.univ-toulouse.fr/ Eprints ID : 18225 Any correspondence concerning this service should be sent to the repository administrator: staff-oatao@listes-diff.inp-toulouse.fr AbstractThe present paper reports non-electrically intrusive partial discharge investigations on an aeronautic motor. Relevancy, robustness and repeatability of partial discharge testing procedures, both on insulating materials characterization and on operating aeronautic equipment are essential to ensure reliability of the aircraft systems. The aim of this paper is to be the very first step of defining such procedures and the associated test equipment.To do so, the paper will start by providing an understanding of partial discharge phenomena and will review typical more electrical aircraft architecture. Key characteristics causing partial discharge risk to increase will be highlighted. The impact of harness length, high performance power electronics and voltage level increase on insulation system is demonstrated.Then, an analysis is carried out from motor design perspective to find out which test procedure is relevant to assess each insulation system performance both at atmospheric and reduced pressures. The study helps to realize the benefits of using multiple test sample and procedure to assess insulation system performance level through the design process of the motor. It is shown that a good agreement observed between stator and representative samples. This paper will also review the ability of the non-intrusive test method to detect partial discharge with a full scope of voltage signal from AC to impulse voltage and under different pressures. The paper concludes with an analysis of results and thoughts about future work regarding motor design taking into account partial discharge risk and evolution of proposed procedure.

Advanced Partial Discharge Testing of 540V Aeronautic Motors Fed by SiC Inverter under Altitude Conditions

“…Results are similar with our previous technical report [6], showing that even a complete rewound of the electric motor lead to stable between phases could be noted suggesting that slot insulation is balanced in all slots.…”

“…The phase to phase insulation is now tested, with two phases Table 10) Again, results are similar with our previous technical report [6], with very few variations between what seems to be a balanced phase to phase electrical insulation. On average, the phase to phase insulation is also weaker than the phase to ground insulation system.…”

“…The design of this stator has been extensively detailed in [6] are tables regarding insulation and electric design are recalled below (Tables 5, 6, 7). The two terminals of each of his three phases are accessible.…”

“…A broad range of operating electric motors have been tested on industrial test benches under nominal conditions detection method [5]. Moreover, a previous analysis illustrated the gains of carrying out a detailed and progressive analysis of the insulation system both under AC and impulse voltage from twisted pair sample to a complete stator [6]. But, as a whole, a key link in the testing chain was still missing.…”

Investigations on Partial Discharges Risk in Aeronautical Rotating Machine Fed by HVDC 540VDC Network

“…To measure PDIV, we used the experimental test bench detailed in [5]. In case of twisted pairs, a 50Hz sinusoidal voltage is applied to one magnet wire and the other is grounded.…”