Improving the starting performance of large salient-pole synchronous machines

We have carried out an engineering study with the aim of enhancing the reliability of the starting system of the salient-pole synchronous machines in a pumping-generating plant. We focused on accurate prediction of the damper bar currents, electromagnetic torque, acceleration time, and bar temperatures during the starting process. We used the time-stepping finite-element analysis (FEA) for a multiple-pole model including coupled field-circuit formulation and rotor motion. We also developed an analytical model, incorporating the equivalent circuit parameters, to simulate the starting performance of the generator/motor units. The predicted results from both the FEA model and the,analytical model agree well with experimental investigations. As a result, we were able to propose a way to improve the motor's reliability and allow many additional starts.