Conceptual design of a high temperature superconducting generator

This paper describes the conceptual design of a high temperature superconducting (HTS) generator for mobile radar (MR) applications. The power system for MR consists of a diesel engine, a generator and power conditioning electronics. Significant improvements in power density, performance and system efficiency result if the generator and the power electronics are cryogenically cooled. The generator supplies power to the radar and the auxiliaries of the system. The generator output required is less than 50 volt AC (RMS phase to neutral) to maximize the efficiency of the cryogenically cooled power electronics. The auxiliaries of the system consume power at 120 V AC, 3-phase, at 60 Hz. The generator is designed to meet both requirements. The diesel engine provides the prime power to the generator at 1800 RPM. The generator is a four-pole two stator winding machine supplying power at 50 V AC, 60 Hz, 12-phase to the power electronics, and 120 V AC, 60 Hz, 3-phase to the auxiliaries of the system. The field winding of the generator consists of HTS coils; the stator has two ambient temperature air gap windings. The cooling of the field winding is provided by heat exchange with helium gas cooled by a Gifford McMahon cryocooler.