Influence of Unbalanced Currents on the Design and Operation of Large Turbine Generators

The influence ofunbalanced currents onthe design and operation of large turbine generators is described beginning with a summary of factory unbalanced current tests. Generator design considerations are discussed, including: rotor design features and practice, effects of short time and continuous unbalanced loading, and influence of unbalanced fault capability on major generator parameters. These considerations plus a summary of operating experience confirm that provision for unbalanced fault capability should not be an overriding consideration in the design of large generators, and support the need for industry standards revision.