Benefits of HTS technology to ship systems

This paper presents results of the 'analysis of high-temperature superconductor benefits for ship systems' study commissioned by U.S. Office of Naval Research (ONR) in 2004. The total power requirement is approaching 100 MW on large U.S. navy surface ships. High-temperature superconductor (HTS) alternating current (AC) synchronous motors and generators scale advantageously compared to other technologies. ONR initiated this study, which focuses on evaluating factors that optimize HTS component weights, sizes, and efficiencies in various ship system configurations. The study concludes that ship electrical systems based on 6.6 kV and 9.9 kV bus voltages are feasible without requiring transformers. On the basis of this analysis, 60 Hz systems at 6.6 kV and 9.9 kV are recommended for both large and small combatant ships. The availability and supportability of commercial-off-the-shelf (COTS) components in 60 Hz systems provides benefits, such as improved reliability, reduced technical risk and reduced cost, while having minimal impact on the system's weight, size, and footprint. Systems using the second generation (2G) HTS wire had improved weight, size, and efficiency benefits over systems using the first generation (1G) HTS wire. The most attractive option for the variable speed drive (VSD) is a diode-clamped pulse width modulated (PWM) drive.