# Control Design

Linearize models and design control systems using Simulink® Control Design™ software

To design and analyze control systems modeled in the Simulink environment, consider using Simulink Control Design software.

Simulink Control Design extends Simulink, allowing you to find operating points and compute exact linearizations of Simulink models at various operating conditions. Simulink Control Design provides tools that let you compute simulation-based frequency responses without modifying your model.

Simulink Control Design provides several approaches to tuning Simulink blocks, such as Transfer function and PID Controller blocks. You can use these techniques and tools to:

• Automatically tune feedback loops containing PID Controller or PID Controller (2DOF) blocks.

• Graphically or automatically tune SISO feedback loops containing any tunable Simulink blocks.

• Tune Simulink models of control systems having any structure to meet high-level design goals such as reference tracking, disturbance rejection, and stability margins.

## Topics

### Trimming and Linearization

To obtain a steady-state operating point, you can trim your model using numerical optimization techniques or simulate your model until it reaches a steady-state condition.
• Linearize Nonlinear Models (Simulink Control Design)
Obtain a linear approximation of a nonlinear system that is valid in a small region around an operating point.
• Choose Linearization Tools (Simulink Control Design)
Simulink Control Design software lets you perform linear analysis of nonlinear models using a user interface, functions, or blocks.
Linearize a model at its operating point consisting of initial state values and input signals.
• Linearize at Trimmed Operating Point (Simulink Control Design)
You can linearize a Simulink model at an operating point that meets specified input, output, or state constraints.

### Frequency Response Estimation

• Frequency Response Estimation Basics (Simulink Control Design)
A frequency response describes the steady-state response of a system to sinusoidal inputs. Simulink Control Design lets you estimate the frequency response of a model or perform online estimation of a physical plant.
• Estimate Frequency Response Using Model Linearizer (Simulink Control Design)
Estimate the frequency response of a Simulink model using a manually constructed sinestream input signal.

### Control System Tuning

At the command line, use `systune` or `looptune` to automatically tune control systems modeled in Simulink.