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H-Infinity Synthesis
Frequency-domain controller design
Robust Control Toolbox™ commands let you apply the powerful methods of
H∞ synthesis to
SISO and MIMO control design problems. Commands such as
hinfsyn
perform traditional synthesis of
full-order, centralized controllers. To tune control systems with
predefined architectures and controller structures, you can use
hinfstruct
. For more information about the
difference, see Difference Between Fixed-Structure Tuning and Traditional H-Infinity Synthesis.
Functions
Topics
H∞ Synthesis of Centralized Controllers
- Robust Control of Active Suspension
In this example, use H∞ synthesis to design a controller for a nominal plant model. Then, use μ synthesis to design a robust controller that accounts for uncertainty in the model. - Control of a Two-Tank System
This example shows how to use Robust Control Toolbox™ to design a robust controller (using D-K iteration) and to do robustness analysis on a process control problem.
H∞ Tuning of Fixed-Structure Controllers
- Fixed-Structure H-infinity Synthesis with hinfstruct
This example shows the complete workflow for tuning a control system withhinfstruct
. - Build Tunable Model for Tuning with hinfstruct
Create a generalized LTI model of the system that includes the fixed and tunable elements and weighting functions that represent your design requirements. - Extract Tunable Control System from Simulink Model
This example shows how to create a tunable model for tuning withhinfstruct
, starting with a Simulink® model of your control system. - Tune and Validate Controller Parameters
Usehinfstruct
to tune the tunable parameters in thegenss
model of your control system. - Speed Up Tuning with Parallel Computing Toolbox Software
If you have the Parallel Computing Toolbox™ software installed, you can speed up the tuning of fixed-structure control systems.
About H∞ Control Design
- Difference Between Fixed-Structure Tuning and Traditional H-Infinity Synthesis
Traditional H∞ synthesis designs a full-order, centralized controller. Fixed-structure tuning lets you specify your control architecture and the structure and parameterization of the tunable elements of your system. - Norms and Singular Values
For MIMO systems the transfer functions are matrices, and relevant measures of gain are determined by singular values, H∞, and H2 norms. - Formulating Design Requirements as H-Infinity Constraints
To usehinfstruct
, you express your design requirements as constraints on the closed-loop gain. - H-Infinity Performance
Many types of control objectives can be posed as a minimization of norms of closed-loop transfer functions. - Interpretation of H-Infinity Norm
There are several ways of defining norms of a scalar signal, which have different physical interpretations and provide different measures of performance.