Block diagram reduction

Block reduction rules It is important to note that blocks can be connected in series only if the output of one block is not affected by the next following block. If there are cascaded blocks, we can replace them by their multiply in one block. Any simple feedback loops can be reduced to one block. Complicated block diagram can be treated step by step to reduce it using the following rules:

Rule (1): Negative feedback

Rule (2): Cascade blocks

Rule (3): Parallel blocks

Rule (4): Moving signal backward

Rule (5): Moving signal forward

Rule (6): Moving summing point

Rule (7): Moving summing point

Rule (8): Order of summing points

Example 2

Example 3

Example 4 Consider the diagram below

Reduce cascaded block Reduce feedback block in internal loop

Remove next feedback block in internal loop

Example 5

Example 6