Processing of high voltage stator insulation system-art or science? an overview

The optimization of processes for the production of high voltage stator coils and bars has often been based on multiple trial runs followed by the qualification and extensive testing of the prototype product. The parameters affecting the steps of flow, gel and cure of the resin matrix within the composite insulation system are many and their interaction extremely complex. The generation of suitable theoretical models, although proposed by many, has been found very difficult in practical application. However extensive characterization and understanding of the theology, reactivity and polymerization process conducted on the base resin can contribute to a better perception of why certain process conditions can be successful and streamline their optimization. Ideally “in-situ” monitoring of the molecular changes occurring during the various process´ steps can further lead to a more direct understanding in real time of the transformation taking place and eventually contribute to process automation. This overview explores the multitude of variables, their interaction and the techniques that can be employed to contribute to convert into a solid science a well-established art