Airflow control for variable speed blowers

摘要

Apparatus and method for controlling an air distribution system of the type which includes a motor drivingly associated with a blower and a duct system, and further including a target air flow rate signal which represents a target air flow for the air distribution system. The apparatus and method provide control of the motor speed to maintain a rate of air flow in the system at substantially the target air flow rate regardless of the status pressure therein. The apparatus provides a speed signal representative of the speed of the motor, and a control signal in response to the target air flow rate signal and the speed signal, and controls the motor speed in response to the control signal. The central signal is provided independent of the duct system. Motor speed is controlled by applying a voltage to the motor which varies in accordance with the control signal for maintaining the rate of air flow in the system at substantially the target air flow rate regardless of the static pressure therein. The control signal is provided by implementing a constant air flow control algorithm which is responsive to both the target air flow rate signal and the speed signal.