Design And Experimental Evaluation Of A High-Speed, Directly-Coupled, Multi-Megawatt Permanent-Magnet Machine.

Abstract

This paper reexamines some of the usual assumptions in deploying synchronous machines in multi-megawatt, high-speed application. The detailed design and experimental evaluation of a prototype high-speed, directly-coupled, multi-megawatt permanent-magnet machine that can operate at common gas turbine speeds a power ratings is presented. The maximum, continuous operating speed of the machine being evaluated is 15k rpm to match the shaft speed of compressors and turbines of up to 8 MW in targeted petroleum and chemical industry application. The machine is characterized by high power-density and high efficiency. The design parameters and the predicted performance are corroborated by component, no-load, loaded and short-circuit tests. The thermal model and the cooling system design are evaluated and calibrated by the temperatures registered during the tests. The total measured losses and the allocation of losses across components are compared with the losses predicted by various analytical and numerical models.