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PostPosted: Tue Feb 14, 2017 8:39 am 

Joined: Mon Jun 01, 2015 8:51 am
Posts: 7
Hello!

Please help with the answer to the question of the right choice of TI and TD parameters for PID FB41 block.
I have a process model in Matlab-simulink, the PID controller is in Step7, FB41 block. Data communication takes place on the OPC protocol. The output of the PID controller (Step7) enters the object in Matlab, where I see the result of the process to scope.

I know that the formula FB41 - K (1 + 1 / Tis + Tds).
Parameters PID controller Matlab I have chosen the following:
Kp=5.7417
Ki=1.6724
Kd=9.4678


I used a variable block FB41 - PV, for input (OPC Read) and output (OPC write).
I also tried to use the signal for the job via the OPC FB41 setpoint (SP_INT), PV ( for the signal after the object) and LMN (for input to object in Matlab).
As a result, in both cases I received a completely different graphics, different from PID controller Matlab and FB41 (Step7) .


How should I choose the parameters of TI and TD, and correctly configure block PID controller FB41 (Step7) knowing the coefficients PID controller Matlab / simulink?

I looked a lot of articles, documentation of FB41, but did not understand how to implement the controller using Matlab and the OPC protocol.

I can send you the Step7 project with the FB41, for example.

I really hope for your help.
Thanks for the answer.
(sos)

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PostPosted: Wed Feb 15, 2017 3:22 am 

Joined: Wed Apr 21, 2010 9:24 pm
Posts: 5
From which OB do you call FB41?


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PostPosted: Thu Feb 16, 2017 1:20 pm 

Joined: Mon Jun 01, 2015 8:51 am
Posts: 7
qqwww wrote:
From which OB do you call FB41?

OB1


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PostPosted: Thu Feb 16, 2017 3:50 pm 

Joined: Wed Apr 21, 2010 9:24 pm
Posts: 5
It is not correct.
You have to use cyclic interrupts like OB30-OB38 for PID regulator.


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