A three phase model for transient overvoltage studies on electrical machines during sequential pole closure

This paper addresses the problem of transient overvoltages in electrical machines during sequential pole closure on industrial installations. A three-phase computer model that includes the circuit breaker, high-voltage cable and electrical machine is proposed. Multiconductor transmission line theory and modal analysis are applied to the components and the piecewise Fourier transform is used to simulate sequential pole closure. The basic mechanism of sequential pole closure is analyzed including the case when parallel capacitors are connected. Finally, a sensitivity analysis on the effect of several system and machine parameters on the dielectric stresses during sequential pole closure is presented.