Feedback Linearization of a Blower in an Anesthesia Workstation

Abstract

Radial compressors, Blowers, which are often used in modern devices for medical ventilation, are known to have non-linear dynamics regarding the generated pressure. To make them accessible for the large field of linear control theory their model needs to be linearized. This paper uses a gray box model of a blower driven by a brushless direct current (BLDC) motor to design a controller based on feedback linearization. The controller is designed to achieve approximate linear closed loop behavior of the system. The controller is then evaluated concerning reference tracking and disturbance rejection in simulation and on a demonstrator system. The evaluation showed that an approximate linear closed loop behavior was achieved.

Keywords

• feedback linearization
• ventilator control
• nonlinear control