setting up closed loop boost control

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setting up closed loop boost control

Postby stainless1 on Sun Jul 17, 2022 9:10 am

OK guys here is my question. I have my MAP set up to read in PSI. I've run on just spring for several years, but now I am attempting boost control. Should my Aim Boost table be set up with PSI numbers or Kpa like in the webinars. I've looked in help files but it does not seem to be covered.
I do have my boost cut set in Kpa but not really sure that should be that or PSI.
Anyone have an answer out there.
Thanks
Stainless
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Re: setting up closed loop boost control

Postby stainless1 on Mon Jul 18, 2022 10:11 am

Well I still don't know for sure, but I thought if you had a 0 in normal position that that area had the solenoid shup off. Well not if you put in a minimum duty cycle. It appears whatever you set in minimum duty runs that until the table has a value that exceeds it. So minimum duty is being shut off. The webinar doesn't tell you that either.
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Re: setting up closed loop boost control

Postby stainless1 on Mon Jul 18, 2022 10:31 am

Make that 0 in normal position and aim boost... had the minimum duty cycle number from the time the motor started
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Re: setting up closed loop boost control

Postby Stephen Dean on Mon Jul 18, 2022 11:14 am

Hi,

Having the units displayed as PSI or kPa will not affect the operation of the boost control system,

What do you have the Activation Pressure set to? If this is too low then the Boost Control system will activate earlier than required.

The Normal Position table is used to create a Feed Forward table for the Boost Control system to reference for the amount of Duty Cycle required for a specific Boost Aim, if you have numbers in this table for a low boost aim and Engine Speed then the system will activate as soon as the activate Pressure parameter is exceeded. When I setup these tables I do not have any data for engine speeds below the point that the turbo will start to generate boost.
Stephen Dean
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Re: setting up closed loop boost control

Postby stainless1 on Tue Jul 19, 2022 11:40 am

Thanks, I just made a dyno run... I set minimum duty to 0, I ran to 10k rpm, the boost solenoid never turned on... 0 duty cycle on the data log. It should have given me DC of 40 and 20lbs of boost. My activation pressure was set to 160 kPa which is about 2 lbs of boost under the spring pressure. My data log showed 26.9 lbs of boost at 10K which is spring and creep.
Should activation be in psi? Should max boost be in PS!
I plan to go back into the tables and eliminate everything below 7K for aim and normal position. This system worked in open loop... so that is why I wonder if I need to keep everything in psi or change everything to kPa.
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Re: setting up closed loop boost control

Postby Stephen Dean on Tue Jul 19, 2022 12:47 pm

Hi,

Can you post the tune file from the M84?

What do you have in the Boost PID Gains?
Stephen Dean
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Re: setting up closed loop boost control

Postby stainless1 on Tue Jul 19, 2022 1:10 pm

Well I will give it a try. With any luck it is attached to this post.
Attachments
1K busa 850 inj blown 30 E85 .m84-12
(72 KiB) Downloaded 1454 times
Last edited by stainless1 on Tue Jul 19, 2022 1:34 pm, edited 1 time in total.
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Re: setting up closed loop boost control

Postby Stephen Dean on Tue Jul 19, 2022 1:32 pm

Hi,

Try this.
Attachments
1K busa 850 inj blown 30 E85 .m84-12
(72 KiB) Downloaded 1421 times
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Re: setting up closed loop boost control

Postby stainless1 on Tue Jul 19, 2022 1:37 pm

To make it easy what did you change? I can't make another dyno run until tomorrow evening.
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Re: setting up closed loop boost control

Postby stainless1 on Tue Jul 19, 2022 1:58 pm

So far it appears you added minimum 15 duty cycle and maximum way to much.... that number will put me at boost cut. I previously had minimum 25 in DC. That gave me 25 for the entire run. The 10K run I had 0 minimum DC and it stayed at 0 the entire run. I checked the Aux 3 output and it buzzed the solenoid.
So I am not getting any boost control, the solenoid is not turning on....
So back to my question earlier... should all my boost control tables, cutoff and activation be in psi? Or should I put my MAP output to kPa?
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