Simulink Control Design™ - MathWorks

Closed-Loop PID Autotuner

Automatically tune PID gains based on plant frequency responses estimated from closed-

loop experiment in real time

Library: Simulink Control Design

Description

The Closed-Loop PID Autotuner block lets you tune a PID controller in real time against a

physical plant for which you have an initial PID controller that yields a stable loop. The

plant remains under closed-loop control of the initial PID controller during the entire

autotuning process. The block can tune the PID controller to achieve a specified

bandwidth and phase margin without a parametric plant model. If you have a code-

generation product such as Simulink Coder, you can generate code that implements the

tuning algorithm on hardware, letting you tune in real time with or without using

Simulink to manage the autotuning process..

If you have a plant modeled in Simulink and an initial PID controller, you can perform

closed-loop PID autotuning against the modeled plant. Doing so lets you preview plant

response and adjust the settings for PID autotuning before tuning the controller in real

time.

To achieve model-free tuning, the Closed-Loop PID Autotuner block:

(^1) Injects a test signal into the plant to collect plant input-output data and estimate
frequency response in real time. The test signal is combination of sinusoidal
perturbation signals added on top of the plant input.
(^2) At the end of the experiment, tunes PID controller parameters based on estimated
plant frequency responses near the target bandwidth.
(^3) Updates a PID Controller block or a custom PID controller with the tuned
parameters, allowing you to validate closed-loop performance in real time.
Unlike with the Open-Loop PID Autotuner block, the loop remains closed throughout the
experiment. Keeping the loop closed helps to maintain safe operation of the plant during
the estimation experiment.
16 Blocks — Alphabetical List