A gain-scheduled controller is a controller whose gains are
automatically adjusted as a function of time, operating condition,
or plant parameters. Gain scheduling is a common strategy for controlling
systems whose dynamics change with time or operating condition. Such
systems include linear parameter-varying (LPV) systems and large classes
of nonlinear systems. To tune gain-scheduled controllers in MATLAB® or Simulink®, you
represent the variable gain as a function of the scheduling variables
tunableSurface command. For an overview
of the workflow for tuning gain-scheduled controllers, see Tune Gain-Scheduled Controllers.
||Create tunable gain surface for gain scheduling|
||Polynomial basis functions for tunable gain surface|
||Fourier basis functions for tunable gain surface|
||Basis functions for tunable gain surface|
||Visualize gain surface as a function of scheduling variables|
||Evaluate gain surfaces at specific design points|
||Get current values of tunable-surface coefficients|
||Set values of tunable-surface coefficients|
Understand the general tuning workflow for using
tune gain-scheduled controllers.
Model a scalar gain that has a bilinear dependence on two scheduling variables.
To tune a gain-scheduled control system in Simulink, model the scheduled gains using Lookup Table or Interpolation blocks.
This example shows how to tune a gain-scheduled controller for a chemical reactor transitioning from low to high conversion rate.
This example uses
generate smooth gain-schedules for a two-dimensional grid of operating
conditions for a control system modeled in Simulink.
Gain scheduling is a strategy for controlling systems whose dynamics change as a function of time, operating condition, or plant parameters.
To tune a gain-scheduled control system, you need a collection of linear models describing the plant dynamics at the selected design points.
A gain surface parameterizes a variable gain in terms of the scheduling variables. Use gain surfaces to model variable gains in a gain-scheduled control system.
Tuning gain-scheduled controllers guarantees suitable performance only near each design point. It is important to validate the tuning results over the full range of operating conditions.
When tuning gain-scheduled controllers, you can specify tuning objectives that depend on the scheduling variables.