Full Description
Scope
This procedure is intended for bars/coils for rotating machines rated 11 kV or more at 50 Hz or 60 Hz that are subjected to many transitions from no-load to full-load current during normal operations, and where rapid load variations are typical. Only the thermal cyclic degradation within the groundwall insulation and/or the conductor package and delamination of the groundwall insulation from the conductor are addressed by this test.The procedure is applicable to the following machines:-- Indirectly cooled combustion turbine generators-- Indirectly cooled pumped storage or peaking load hydrogenerators-- Indirectly cooled synchronous condensersNo pass/fail criteria are presented; rathere, the test results on a variety of stator bars and coils are compared.Pass/fail criteria may be established by users of this recommended practice.
Purpose
A test method to determine the relative ability of high-voltage form-wound stator bars and coils of large rotating machines to resist deterioration due to rapid heating and cooling resulting from machine load cycling is described. The test procedure is primarily intended for machines where the stator windings are indirectly cooled by air. This procedure provides a recommended practice for performance of thermal cycle testing of form-wound stator bars and coils without the use of simulated core. Since thermal cycling tests will result in aging of the insulation of the bar or coil, prototype or spare bars or coils obtained from a normal production run must be used in the test.Thermal cycle testing of bars and coils confined in a simulated core, that would simulate the effects of the core, would require different parameters and therefore is not covered by this procedure.
Abstract
New IEEE Standard - Superseded.A test method to determine the relative ability of high-voltage, form-wound stator bars and coils of large rotating machines to resist deterioration due to rapid heating and cooling resulting from machine load cycling is described.
