# Block Diagram Reduction Technique - Transfer Function - Control Systems | Summary and Q&A

3.8K views
April 11, 2022
by
Ekeeda
Block Diagram Reduction Technique - Transfer Function - Control Systems

## TL;DR

Learn how to simplify complex block diagrams and determine the transfer function using the block diagram reduction technique.

## Install to Summarize YouTube Videos and Get Transcripts

### Q: What is the first rule of the block diagram reduction technique?

The first rule is about calculating the output of a block, which is equal to the transfer function of the block multiplied by the input to the block. It helps us determine the output of a block in a block diagram.

### Q: How are blocks connected in series reduced?

Blocks connected in series can be replaced by a single block with a transfer function equal to the multiplication of the individual transfer functions. This simplifies the block diagram and helps find the overall transfer function of the system.

### Q: How are blocks connected in parallel reduced?

Blocks connected in parallel can be replaced by a single block with a transfer function equal to the algebraic sum of the individual transfer functions. The signs of the transfer functions determine whether to add or subtract. This simplifies the block diagram.

### Q: How are summing points and takeoff points rearranged in a block diagram?

Summing points can be interchanged without affecting the output. Takeoff points can be shifted after a block by dividing the takeoff signal by the transfer function of the block. Takeoff points can also be shifted before a block by multiplying the takeoff signal with the transfer function of the block.

## Summary & Key Takeaways

• Block diagrams can be complicated with interconnected loops and feedback loops, making it difficult to determine the overall transfer function of a system.

• The block diagram reduction technique involves rearranging and applying rules to simplify block diagrams and find the transfer function.

• Rules include calculating the output of a block, reducing blocks in series and parallel, interchanging summing points, shifting takeoff points, and more.