Direct and Quadrature Models for High Energy Pulsed Alternators

Rotating machinery can be used to store kinetic energy and convert it to high current electrical energy in the millisecond time frame required by pulsed loads such as electromagnetic launchers. Machines used in these applications, called pulsed alternators, often require nonstandard features, such as low impedance, more than three phases, or compensating windings inside or conductive shields outside the machine. Design and analysis of systems utilizing pulsed alternators require accurate transient modeling. We present a direct and quadrature (DQ) representation of the system dynamics for nonstandard electric machines used in pulsed power applications, which can be used to construct efficient simulation models. Simulation results using the resulting model are presented and compared to an existing model, which has been validated with test data.