Mechanical circulatory support systems with dual-drive architecture: a reliability and efficiency-oriented approach

Abstract Mechanical circulatory support (MCS) systems are implantable devices designed to assist or replace the pumping function of a failing heart, ensuring adequate systemic circulation. Because they must operate continuously and under variable physiological loads, these systems require compact and energy-efficient electric drives. This study examines an MCS configuration that integrates a dual axial-flux permanent magnet synchronous motor (dual-AFPMSM) and operates it with a load-sharing strategy to improve overall efficiency and extend battery life. In the proposed approach, the torque demanded by the axial-flow pump is distributed between two identical AFPMSMs so that each motor operates closer to its high-efficiency region, thereby reducing AFPMSM losses; this is the fundamental mechanism behind the efficiency gain. The AFPMSM was integrated into the axial-flow pump with priority given to volumetric efficiency and unobstructed blood flow, and application-specific constraints were considered during the mechanical design. Finite element analysis (FEA) was used to validate motor performance under the target operating conditions. A comparison of single- and dual-AFPMSM operation shows that, under rest conditions, load sharing improves efficiency by 11.8%–17.4%, while under exercise conditions it improves efficiency by 6.5%–14.7%. This reduction in electrical power demand translates into up to a 14.6% increase in battery operating time during exercise. These results indicate that a dual-AFPMSM architecture with explicit load sharing is a promising option for next-generation MCS devices, providing reliable circulatory support with improved energy utilization and longer runtime.