AI Article Synopsis
- Magnetic bearings support rotating machines without contact or lubrication, making them suitable for applications like mechanical heart pumps.
- The LifeFlow heart pump from the University of Virginia utilizes active and passive magnetic bearings to stabilize its impeller, although designing the control for these bearings poses challenges.
- A three-dimensional finite element analysis of the magnetic bearing system was conducted to provide critical parameter values, leading to an optimized controller design and a more efficient motor with a smaller footprint.
Article Abstract
The non-contact and lubrication free support of magnetic bearings make them ideal to support rotating machines. One area of application of magnetic bearings is in the design of the mechanical heart pumps. The LifeFlow heart pump developed by the University of Virginia is one such heart pump which uses active and passive magnetic bearings to support the impeller. The design and controls of such bearings can be quite challenging. One of the major difficulties that one may encounter in designing the controller is to get accurate values of the control parameters such as bias flux, radial and axial stiffness values, forces, etc. In order to obtain these parameters accurately, a three dimensional finite element analysis of the magnetic bearings is crucial. This paper covers the analysis of the magnetic bearing system used in the LifeFlow Heart pump. The main purpose of the analysis was to provide accurate values of air gap flux, forces, radial and axial stiffness in order to design a robust and optimized controller for the bearings. As a result of the analysis, these parameters have been determined and the motor is being redesigned with a smaller footprint to achieve higher efficiency.
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