ResMed is a leading global manufacturer of medical equipment designed to treat and manage sleep apnea and other chronic respiratory problems. The latest battery-powered CPAP and lung ventilation devices bringing patients relief require small electric BLDC motors, and low-power consumption is key to their design.
Because this is a high rotational speed application, these motors are required to work with high frequency voltage and current. This raises the need for a high degree of accuracy when evaluating the efficiency of these BLDC motors during the design phase.
In this presentation, Aleksandr Nagorny, principal engineer at ResMed, walks through the methodology and simulation results of how Infolytica MagNet software was used to perform accurate efficiency estimates for the small high-speed motors. Specifically, the simulation of such motors needs to take into account all types of losses related to the high frequency application, including stator core losses, losses in the magnet, and losses in the bearings from stray magnetic fields. MagNet was crucial to estimating the optimal firing angle for the CPAP motor-blower along with a validating a variety of other design parameters.