Analysis of asymmetrical faults in synchronous generators by d-q-0 frame of reference

The paper describes the development of a mathematical model in the d-q-0 frame of reference for the analysis of unbalanced operation of synchronous machines. The equations for faults between two phases and between one line and the generator neutral are described. The solution of the equations of the model by digital computer is presented. Initially, the model neglects nonlinearities and subtransients in the synchronous generator. The validity of the method of analysis developed is examined by comparing the computed results with the test results for a 7 MW generator and a 50 MW generator.