Anwendungsorientierte Charakterisierung isolierter Flachdrähte für die Hairpinstatorproduktion ; 1. Auflage

Abstract

The long-term success of electromobility depends crucially on its price competitiveness. To achieve competitive target costs, product and process competencies must be built up quickly and high production volumes must be realized to achieve economies of scale. Since these are largely new technologies, the required quality levels and acceptable scrap rates are only achieved slowly – a significant obstacle to economically viable production. In the field of electric drives for electric vehicles, hairpin technology for the stator has now become established as the state of the art. In this process, insulated flat wires are bent in highly automated processes, inserted into the stator lamination stack, and contacted with each other. Precisely because of the novelty of many product and process technologies, corresponding expertise must first be built up along the entire value chain. The semi-finished product of insulated flat wire represents a critical component. Increasing voltage levels in the electric drivetrain combined with high mechanical loads during production make the insulation susceptible to quality problems that, in the worst case, can lead to failure of the entire electric drive unit. Due to the lack of experience with this technology, there is a fundamental lack of understanding of the interactions between process parameters and the properties of the semi-finished product along the entire value chain. Users need this understanding to translate the requirements of stable production processes into concrete requirements for the semi-finished product. Semi-finished product manufacturers, in turn, must be able to understand the requirements from the application and translate them into corresponding material properties. The aim of this work is to systematically derive requirements for insulated flat wires from the interactions between material properties and process parameters of hairpin stator production, as well as to develop methods and tools to ensure these material requirements are met. The chosen solution approach of application-oriented characterization of insulated flat wires leads to the development of testing procedures that examine properties of insulated flat wires with regard to stable production processes. These procedures are suitable in a further step for describing the requirements for the semi-finished product from a process perspective. The research process of this work follows the framework of Design Science Research. In accordance with this methodology, the work is structured into eight chapters. First, the fundamental theoretical foundations are described, on the basis of which the deficit from industrial practice is derived through a conducted study. The concrete solution approach is developed in three overarching steps: The testing procedures are first conceptualized, then technically and methodologically designed, and finally validated and transferred into the application context.

Authors 1

1. Henrik Born corresponding Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen