Lecture Plan

1
Lecture Plan

• Overview of systems
• Open and Closed Loop Diagrams
• Creating Block Diagrams
• Combining Block Diagrams
• Reducing Block Diagrams
• Systems
• Similarity Of Systems
• - electrical, mechanical etc.
• Dynamic Systems
• Complete systems
• System response

2
Open v Closed loop
Inputs System Outputs Inputs System
Outputs Feedback

• Open loop is simple but vulnerable to changing
  the conditions.
• Closed loop accounts for changes in conditions,
  but complex and may become unstable.

3
Components

• Block
• or / or function of the system signal
• Summing junction
• and/or the system signals
• Take-off point
• The system signal can be used elsewhere, but not
  affected

Voltage V1 kV1
k
Only one input and only one output
Voltage V1 V1 V2 V2
Up to three inputs and only one output
Voltage V1 V1 V1
Only one input and many outputs
4
Mechanical Components

• Spring FKx
• Damper FDv
• Mass FMa
• Source Nise 2004

5
Mechanical Components
Equation Force - Force - Velocity Distance

• Spring
• FKx
• Damper
• FDv
• Mass
• FMa
• Source Nise 2004

6
Mechanical Components
Force - Impedance Distance

• Spring
• Damper
• Mass
• Source Nise 2004

7
Electrical Components
Voltage - Impedance Current

• Capacitor
• Resistor
• Inductor
• Source Nise 2004

8
Other Components
Pressure - Impedance Flow

• Liquid
• Capacitor - Storage tank
• Resistor - Resistance
• Inductor
• Thermal
• Capacitor - Thermal capacitance
• (specific heat capacity)
• Resistor - Thermal Resistance
• Inductor

Temperature difference - Impedance Heat Flow
9
Antenna example
Source Nise 2004
10
Block diagram
Source Nise 2004
11
Tutorial question

• Determine the block diagram for each component?

Source Nise 2004