Comparing the Low-Cost Measuring Devices for Standstill Frequency Response (SSFR) Testing for Electric Machines

This paper compares the different versions of hardware realization of low-cost device for standstill frequency response SSFR testing. The SSFR testing is a modern method used for testing and parameter identification for electrical machines especially for synchronous machines (high power generators for power stations). This paper shows the methods how to realize this SSFR testing device for machine identification by general purpose components (to achieve universal device not only for SSFR testing but also for purposes of more universal usage (i.e. measuring of non-linear power systems, power system fault identification, nonsymmetrical differences measurement, etc.). This modern method makes it possible to replace the Sudden Short-circuit Measurement Method and thus saves the mechanical construction and lifetime of the machine, which might be otherwise reduced due to the strong dynamic forces that occur in this type of measurement. Proposed devices were realized in university laboratories for purpose of getting acquainted with the practical properties of this method and also for didactic purposes (both in terms of the SSFR method itself and in term of realization of a real equipment with given properties).