Point-Vector-Based Assessment of Surge Current of Powerful Synchronous Machines from Sudden Short-Circuit Tests

A point version of phase surge-current estimates based on the results of oscillography of transient processes in sudden short-circuit tests is presented. The resulting surge current, determined by a point method, has two main directions: with allowance for the determination of the parameters for identifying the components of the stator current and without it. The resulting surge-current equation makes it possible to calculate the surge current taking into account the identification parameters of all its components. In this case, it becomes possible to check the surge-current estimate for absolute equality to the first vertex in the initial node of the phase current shift, or to detect a deviation of the surge-current estimate from its reliable level.