Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Bode diagram of closed loop transfer functions

Status
Not open for further replies.
B

bunalmis

Full Member level 5
Joined
Jan 3, 2003
Messages
275
Helped
19
Reputation
38
Reaction score
13
Trophy points
1,298
Location
Ireland
Activity points
2,168
I am reading books about drawing bode diagrams.

All drawing examples for the open loop transfer functions.

Why open loop? Why we dont draw the bode diagram of closed loop transfer functions?

Best regards.
 

Re: Bode diagrams ?

You can draw the Bode plots of any math function that is the ratio of two polynomials or just one polynomial to a constant.
 
Re: Bode diagrams ?

If a system will always operate in closed-loop then you will want the bode plot of the closed-loop system, however there are cases where the closed-loop system is used a benchmark for the open-loop system. An example of this is when you add compensators to a system to correct gain or phase margin of the open-loop system, but want to maintain a certain "closed-loop" steady state error, this allows you to adjust gain of the closed-loop system to match the specification, but the system itself operates in open-loop or is only one component of a larger system which may or may not be closed.

You can learn information from the open-loop bode plot about how the closed-loop system.

- Jayson
 

Re: Bode diagrams ?

Jayson thanks. Can you explain?

If system work closed loop why we interest by bode diagram of the open loop system so we can draw the bode diagram of the closed systems.
 

Bode diagrams ?

The bode plot of the open loop system provides you the gain, gain margin and phase margin. Based on this info, you can design the feedback network in order to meet the system requirement (gain, stability, ...).
 

Bode diagrams ?

i think another way to think about this is that, in order to design a closed loop system probably, we must know the behavior of the open loop system (bode plot).
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top