Model Interconnection
Series, parallel, and feedback connections; block diagram building
Interconnecting models of components allows you to construct models of control systems. You can conceptualize your control system as a block diagram containing multiple interconnected components, such as a plant and a controller connected in a feedback configuration. Using model arithmetic or interconnection commands, you combine models of each of these components into a single model representing the entire block diagram.
Functions
feedback | Feedback connection of multiple models |
connect | Block diagram interconnections of dynamic systems |
sumblk | Summing junction for name-based interconnections |
series | Series connection of two models |
parallel | Parallel connection of two models |
append | Group models by appending their inputs and outputs |
blkdiag | Block-diagonal concatenation of models |
imp2exp | Convert implicit linear relationship to explicit input-output relation |
inv | Invert dynamic system models |
ctranspose | Conjugate dynamic system model |
lft | Generalized feedback interconnection of two models (Redheffer star product) |
connectOptions | Options for the connect command |
Topics
Model Interconnection Basics
- Why Interconnect Models?
Interconnecting models of system components allows you to construct models of control systems. - Connecting Models
This example shows how to model interconnections of LTI systems, from simple series and parallel connections to complex block diagrams. - Numeric Model of SISO Feedback Loop
Interconnect numeric LTI models to build a single model of a closed-loop system. - Control System Model with Both Numeric and Tunable Components
Interconnect fixed components and tunable components to build a tunable control system model. - Multi-Loop Control System
Build arbitrary block diagrams with any number of control loops by interconnecting models using the connect command. - MIMO Control System with Fixed and Tunable Components
This example shows how to build a MIMO control system using connect to build a dynamic system model representing a block diagram with both fixed components (Numeric Linear Time Invariant (LTI) Models) and tunable components (Control Design Blocks). - MIMO Feedback Loop
Obtain the closed-loop response of a MIMO feedback loop three different ways. - Using FEEDBACK to Close Feedback Loops
This example shows why you should always use FEEDBACK to close feedback loops.
Analysis Points
- Mark Analysis Points in Closed-Loop Models
Insert analysis points at locations of interest when you build control system models. Use analysis points for extracting system responses from the model. - Control System with Multichannel Analysis Points
Build a control-system model with analysis points for extracting responses at different points in the system.
More About Model Interconnections
- Catalog of Model Interconnections
Block diagram connections correspond to model interconnection commands or arithmetic expressions. - How the Software Determines Properties of Connected Models
When you interconnect models, the resulting model’s properties depend on the properties of the models you are connecting. - Rules That Determine Model Type
Precedence rules determine the resulting model type when you interconnect models of different types. - Recommended Model Type for Building Block Diagrams
Choice of model type can affect numerical accuracy when you interconnect models. - Preventing State Duplication in System Interconnections
This example shows guidelines for building minimum-order models of LTI system interconnections.
