Magnetic Bearings for Supercritical CO2 Service

Supercritical CO2 power cycles are being developed for both utility-scaled power generation applications, as well as smaller waste heat recovery applications. Supercritical CO2 cycles are more efficient than current cycles, and the associated turbomachinery components are significantly smaller than that for current steam turbine-based power generation. However, sCO2 cycles operate at a combination of high pressure and high temperature, resulting in turbomachinery design issues that must be addressed so that the sCO2 systems can be developed as quickly as possible with minimum cost. Of particular importance is obtaining acceptable bearing, seal, and rotordynamic performance. The purpose of this SBIR program is to develop and implement a magnetic bearing solution for sCO2 application. Magnetic bearings have several advantages over currently-used bearings, including allowing for an improved different turbomachinery design/layout configuration to be used, so that sealing will be easier. An added benefit is that magnetic bearings can be used as a real-time measurement and diagnostic tool, a capability which is especially useful in diagnosing bearing and rotordynamic problems. This capability will allow sCO2 system technology to develop faster, and with lower risk. The commercial application for the proposed technology is a better bearing/seal/rotordynamic solution, for not only utility scale sCO2 systems, but also for smaller waste heat recovery systems that use sCO2 cycles.