초록 ▼

A Variable Horizon Predictor (VHP) compensates for dead time, measured disturbances, and time variant dynamics in process control loops. The VHP is comprised of a process model, an uncorrected prediction vector unit, a prediction correction unit, a corrected prediction vector unit, and a horizon sel

A Variable Horizon Predictor (VHP) compensates for dead time, measured disturbances, and time variant dynamics in process control loops. The VHP is comprised of a process model, an uncorrected prediction vector unit, a prediction correction unit, a corrected prediction vector unit, and a horizon selection unit 54. The VHP applies a controller output signal to the process model to form a prediction vector that is stored in the uncorrected prediction vector unit and predicts the process output signal over a prediction horizon. The prediction is corrected by the prediction correction unit, which compares the prediction vector to the process output signal. The corrected prediction vector is then stored in the corrected prediction vector unit. The horizon selection unit isolates a portion of the prediction vector to form a subvector and feeds the subvector to an error vector calculator to form an error signal that is applied to the controller. A multivariable interactive control system is implemented by coupling plurality of VHPs and a plurality of loop interaction compensators to a process having a plurality of control inputs and a plurality of control outputs.

대표청구항 ▼

A variable horizon predictor (41) for use in a control loop (42) having a process under control (46) and a controller (44), wherein the controller (44) has a controller output for providing a control signal and a controller input for receiving an error signal, and the process (46) has a process inpu

A variable horizon predictor (41) for use in a control loop (42) having a process under control (46) and a controller (44), wherein the controller (44) has a controller output for providing a control signal and a controller input for receiving an error signal, and the process (46) has a process input for controlling a process variable, with the process input coupled to the controller output to receive the control signal, and a process output for providing a process output signal representative of the process variable, the variable horizon predictor comprising: a process model (48) having a model input coupled to the controller output to receive the control signal and a model response output for providing a model response signal based on the control signal; a prediction vector unit (51) having a prediction vector output for providing a prediction vector and a model response input coupled to the model response output of the process model (48) to receive the model response signal, wherein the prediction vector comprises predicted future values of the process output signal; a horizon selection unit (54) having a prediction subvector output for providing a selected subvector of the prediction vector and prediction vector input coupled to the prediction vector output of the prediction vector unit to receive the prediction vector, wherein the horizon selection units selects a prediction subvector from the prediction vector; and an error scalar/vector calculator (58) having an error signal output coupled to the controller input and a subvector input coupled to the subvector output of the horizon selection unit to receive the subvector, wherein the error vector calculator produces an error signal based on a set point signal and the prediction subvector.