Standstill frequency response tests for model identification of a synchronous machine

This paper presents the parameter identification of a specific wound-field synchronous machine prototype designed for an electric vehicle drive train. Standstill frequency response (SSFR) tests, originally developed against the background of stability analyses for large generators, are used here to acquire extensive and detailed data on the machine´s transient behaviour. The test setup for the data recording is presented and also the basic theory of SSFR is shortly introduced. Thereafter the SSFR data is presented and subsequently analysed to derive parameters of direct and quadrature axis electric equivalent circuits. The frequency responses of the resulting circuits are plotted against the test data to show a proper match. To enable control design in the state space, the transformation of the equivalent circuits into state space representation is finally proposed.