Patent ID: 6979257
Filing Date: 2005-12-27
Classification: B64D,G05D

Abstract:
1. A pressure control system having an inflow unit for admitting pressurized air into a cabin of an aircraft and for regulating the air pressure within the cabin, comprising: an outflow unit including a motor for operating a valve for controllably discharging the pressurized air from the cabin at a specified rate, the outflow unit receiving a motor control signal that sets the speed of the motor in a forward or reverse direction to incrementally open or close the valve at a corresponding valve speed, the valve assuming a corresponding valve position to discharge air from the cabin at the specified rate; a first air pressure sensor disposed within the cabin for determining a cabin pressure level signal representing the air pressure within the cabin; a second air pressure sensor disposed outside the cabin for determining an ambient pressure level signal representing the air pressure outside the cabin; and a control unit coupled to receive the cabin pressure level signal and the ambient pressure level signal and operable, in response thereto, to (i) compute a cabin pressure level rate of change signal based on the cabin pressure level signal, (ii) compute a commanded pressure level signal based at least in part on the ambient pressure level signal, (iii) compute a commanded pressure level rate of change signal based on the commanded pressure level signal end the cabin pressure level signal, (iv) compare the cabin pressure level rate of change signal with the commanded pressure level rate of change signal to thereby determine a cabin pressure rate of change error signal, and (v) generate the motor control signal based on the cabin pressure rate of change error signal, wherein the outflow unit, the first air pressure sensor, and the control unit are coupled together to form a feedback control loop having an operating point, the operating point of the feedback control loop being determined independently from the motor speed, the valve speed, end the valve position feedback.