Gain scheduling is a common technique for controlling nonlinear systems with dynamics changing from one operating condition to another. Gain scheduling is used when a single set of controller gains does not provide desired performance and stability throughout the entire range of operating conditions for the plant.
Designing a gain-scheduled controller typically involves the following steps:
- Linearize nonlinear plant model at different operating conditions to obtain linear models that describe plant behavior in the vicinity of the operating point that a linear model corresponds to.
- Tune controller gains for all the linear plant models.
- Implement a gain-scheduled controller architecture, where controller gains are “scheduled” with a scheduling variable, such as a measured output or a system state.