P08028: Magnet Centering Device

Reports to the LVAD Heart Pump and Magnet Centering Device

Report Number 004: Apparent magnetic run-out of HE magnets fabricated prior to August 2006 and of Chinese magnets

Report Number 006: Abstract: Results from rotating the magnets in the magnetic levitation test stand showed that the hall effect sensors were reading an oscillating wave form or a sin wave. The magnitude of this wave was larger then expected and required further inspection. Several tests indicate that the source of this oscillation is that the magnetic field of the magnets is not concentric with the physical magnet. The field appears to be about 0.004 inches (from this point forward referred to as 4 mils) off center over the entire circumference.

Report Number 007: Abstract: The purpose of this experiment is to determine if the magnetic runout changes with zposition. The z-position was changed from -5000 microns to 2000 microns in 400 micron increments. The sensitivity and runout were determined at every point and plotted. It was concluded that the minimum magnetic runout occurred at the peak of sensitivity.

Report Number 010: Abstract: Discuss the problem associated with the magnets inconcentric fields and the current test rig used to correct the problem.

Report Number 014: Abstract: In order to further reduce the total run-out of the Hall Effect (HE) Magnets, a technique was developed to ensure that the magnet was rotating perfectly around its OD. By reducing the physical run-out to virtually zero run-out (VZR; less than 0.0003 inches), we can then look at the true apparent magnetic run-out.

Report Number 016: Abstract: This report attempts to orbit the magnet around the magnetic center, to further reduce the total run-out. To do this we complete the Magnet OD Orbit and then continue with a Standard HESA Test (SHT) using magnet 6I with 1 Layer or washers. This report has links to the experimental data associated with the experiments.

Report Number 023: Abstract: This document describes the results for mapping the characteristics of a Hall Effect Magnet in order to determine the quality of the magnet and the possibility of implementing it into use for the lvad-rotor.

Links - ftp://lvad.rit.edu/array1/LVADServer/Reports/