Main Content

Design Two-Degree-of-Freedom PID Controllers

UsingpiD Tuner, you can tune two-degree-of-freedompiD Controller (2DOF)和Discrete PID Controller (2DOF)blocks to achieve both good setpoint tracking and good disturbance rejection.

About Two-Degree-of-Freedom PID Controllers

A two-degree-of-freedom PID compensator, commonly known as anISA-PID补偿器, is equivalent to a feedforward compensator and a feedback compensator, as shown in the following figure.

The feedforward compensator is PD and the feedback compensator is PID. In thepiD Controller (2DOF)和Discrete PID Controller (2DOF)块，设定点重量b和cdetermine the strength of the proportional and derivative action in the feedforward compensator. For more information, see thepiD Controller (2DOF)和Discrete PID Controller (2DOF)block reference pages.

调整两度自由PID控制器

piD Tunertunes the PID gainsP,I,D, andN. For thepiD Controller (2DOF)blocks, the tuner also automatically tunes the setpoint weightsb和c. You can use the same techniques to refine and analyze the design that you use for tuning one-degree-of-freedom PID controllers.

To tune a 2-DOF PID controller block in a Simulink®model:

  1. Double-click the block. In the block parameters dialog box, clickTune.

    piD Tuneropens, linearizes the model at the model initial conditions, and automatically computes an initial controller design that balances performance and robustness. In this design,piD Tuneradjusts the setpoint weightsb和cif necessary, as well as the PID gains. To see the tuned values of all coefficients, clickShow Parameters.

  2. 分析和完善初始设计，如Analyze Design in PID Tuner. All the same response plots, design adjustments, and options are available for tuning 2-DOF PID controllers as in the single-degree-of-freedom case.

  3. Verify the controller design, as described inVerify the PID Design in Your Simulink Model.

Fixed-Weight Controller Types

When you tune apiD Controller (2DOF)块INpiD Tuner,Typemenu shows additional options for specifying the controller type. These options include controllers with fixed setpoint weights, such as the controllers described inSpecify PI-D and I-PD Controllers.

The availability of some type options depends on theControllersetting in thepiD Controller (2DOF)block dialog box.

Type Description ControllerSetting in Block
PIDF2 二自由度PID控制器derivati过滤器ve term.piD Tunertunes all controller parameters, including setpoint weights. piD
PIDF2-fixbc 二自由度PID控制器derivati过滤器ve term.piD Tunerfixes setpoint weights at the values specified in the controller block. piD
piDF 2-DOF controller with action equivalent to a 1-DOF PIDF controller, with fixedb = 1和c = 1. piD
I-PDF 二自由度PID控制器derivati过滤器ve term, with fixedb = 0和c = 0. piD
IDF-P 二自由度PID控制器derivati过滤器ve term, with fixedb = 0和c = 1. piD
pi-DF 二自由度PID控制器derivati过滤器ve term, with fixedb = 1和c = 0. piD
pi2 2-DOF PI controller.piD Tunertunes all controller parameters, including setpoint weight on proportional term,b. pi
pi2-fixbc 2-DOF PI controller with filter on derivative term.piD Tunerfixes setpoint weightbat the value specified in the controller block. pi
pi 二元控制器具有相当于1-DOF PI控制器的动作，固定b = 1. pi
PDF2 2-DOF PD controller with filter on derivative term (no integrator).piD Tunertunes all controller parameters, including setpoint weights. PD
PDF2-fixbc 带有过滤器的2-DOF PD控制器。piD Tunerfixes setpoint weights at the values specified in the controller block. PD
PD 2-DOF controller with action equivalent to a 1-DOF PD controller, with fixedb = 1和c = 1. PD

相关话题