Quality Assuring of Stator Winding Production : Using electrical tests to quality assure the process steps of a series stator winding production

Abstract: The demands for sustainable transportation have made battery electric vehicles an increasingly popular subject in the world of both businesses and engineering. This thesis has been made in collaboration with Scania, which is currently investigating the possibility of manufacturing stators and rotors in-house in a series production line. For Scania, the topic of quality assurance is of great importance as Scania wants to ensure their trucks and buses fulfil the quality requirements of both customers and society. The goal of the thesis is to provide Scania with a set of guidelines for what quality assurance steps to perform in a series stator winding production, and where in the production they should be placed. The investigated stator winding type is a continuous hairpin winding, and the investigated quality assurance steps are solely electrical tests used to ensure the safety, functionality, and quality of the stator windings. A process-failure modes and effects analysis were conducted to identify the risks associated with each production step. The results indicates where the quality assurance steps should be taken. Further analysis, based on the provided background of electrical tests, also provides an answer to what electrical tests to perform as quality assurance steps. The result of the thesis is a concept, presented in a flow chart diagram, which indicates what electrical tests to perform and where the tests should be performed in the stator winding production chain.