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Project: T142700 #0390

This Guide presents the detailed requirements and activities that must be performed for acquiring and installing a stator winding. Adherence to the outlined steps will maximize unit availability and reliability. The primary focus is on the stator winding, which is most often the electrical component that demands the greatest attention during replacement. Rotor field windings are also discussed in detail, as they require periodic replacement or refurbishment, although not generally as often as the stator.

The stator winding may be a multi-turn coil or a Roebel bar style. Since each has its own characteristics with respect to installation, they are discussed separately. Similarly, rotor field winding refurbishment and replacement are discussed in detail to clearly describe the merits of rehabilitation versus simple replacement.

The guide covers the elements for an appropriate stator winding specification and a detailed generic rewind and installation specification is also included. In particular, best manufacturing practices are integrated into the guide to bring relevant points to the attention of the reader. In addition, the need and relevance of both in process and final testing to the quality of a rewind are covered. Generally, the rewind guide is focused on the following activities:

– How to remove an existing winding, both stator and rotor field.

– How to make ready and confirm that the stator core is ready to accept a new winding.

– How to exert control, through the specification, on the replacement winding quality and, to the extent possible, its materials and sub-systems.

– How to perform a successful quality installation of a new stator winding.

– Inspection points and activities for both the manufacturing and installation processes.

The guide makes suggestions regarding appropriate or commonly used criteria for what is considered a quality winding. However, it is recognized that these may neither be standard nor appropriate for a given case. Criteria are presented merely as guidelines and do not, in themselves, guarantee a long winding life since too many variables prevent a conclusive winding life expectancy. The degree of attention to detail by the user of this guide may be governed by the size, age or importance of the machine and the guide can be closely or loosely followed to accommodate these factors. The goal is to provide as much detail as is reasonably possible to permit appropriate customization while ensuring that no important elements have been overlooked. The contents of the guide collectively enhance the likelihood of a successful rewind and of achieving the desired service life.


Hydro generator, Generator, Stator, Rotor, Winding, Rewind, Core, Pole