Generalised system model for slipring machines

The general structure of a circuit model of a slipring machine is established in this paper. The model is shown to be advantageous in many types of analysis of a machine when it is a part of a system. A specific circuit model of a synchronous machine (which was derived from Park´s equations) has advantages in the stability analysis of multimachine power systems. The paper provides a more general and basic circuit model (applicable to any slipring machine) utilising the actual physical parameters of the machine. This is done with the view to extending the application of the circuit model to the study of asymmetrical faults or unbalanced operation. In such an analysis, the use of transformed ¿ß0 or dq0 components has no advantages. The advantages of this model in transient analysis over the existing models are shown to be the ease of formulation of the system equations, the elimination of the necessity to invert a time-varying inductance matrix and the ease of obtaining analytical solutions in a linear analysis. The specific circuit model, used for stability analysis, is actually derived from the general circuit model presented. Further, the model is also applicable to any slipring machine with or without m.m.f. harmonics.