Question

Briefly discuss, in your own words (in less than 200 words), how the Simulink software package within MATLAB is able to simulate system midels through block diagram representation of one or more differential equations. Include examples of key system blocks used and other software library features.

Answer 1

Solution

Block Diagram

A block diagram is a visual representation of a model in the Simulink Editor. The editor allows you to add blocks which is selected from block libraries representing elementary model components. Elementary components includes the integrator, gain, and sum blocks. Blocks are connected to each other with signal and event lines to visually construct the model equations.

Block Diagram Semantics

A classic block diagram of a system is drawn graphically with blocks and lines. The history of these block diagrams is derived from engineering areas such as Feedback Control Theory and Signal Processing. A block within a block diagram defines a model in itself. The relationships between elementary models are represented by signal lines connecting the blocks. The blocks and lines in a block diagram collectively describe the overall model of a system.

Simulink extends classic block diagrams by:

• Adding a set of equations (block methods) to each block which defines the time-based relationships between the input signals, output signals, andalso the block state variables.

• Adding parameters to the each block that specify the coefficients from the model equations.

• Providing an engine for numerical solution of the block diagram by evaluating the relationships over time, where time starts at a user-specified “start time” and ends at a user-specified “stop time

• . Here ,Blocks are the main elements you use to build models in Simulink. Use the Library Browser to browse and search the block libraries. When you find the block you want to use, add it to your model.