MS2 3.4.2 - Closed Loop Boost Control
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MS2 3.4.2 - Closed Loop Boost Control
I've been playing with the closed loop boost control for a while now.
I can get okay results, but I would like clarification on the way the PID terms work.
The way I understand it is like this:
0 = nothing
1 = smallest amount/smallest influence
100 = largest amount/largest influence
Cheers
I can get okay results, but I would like clarification on the way the PID terms work.
The way I understand it is like this:
0 = nothing
1 = smallest amount/smallest influence
100 = largest amount/largest influence
Cheers
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Re: MS2 3.4.2 - Closed Loop Boost Control
Bumping this back to the top.
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Re: MS2 3.4.2 - Closed Loop Boost Control
Yes, except that they top out at 200 instead of 100.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
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Re: MS2 3.4.2 - Closed Loop Boost Control
Why doesn't closed loop boost control use the open loop "boost control duty table" as a feed forward term and apply the PID to this value?
This feature does not work with the current control strategy.
This feature does not work with the current control strategy.
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Re: MS2 3.4.2 - Closed Loop Boost Control
Because the open loop table doesn't specify what boost amount the numbers will actually give you. It uses an initial value table as a feed-forward instead.DisgruntledMotorist wrote:Why doesn't closed loop boost control use the open loop "boost control duty table" as a feed forward term and apply the PID to this value?
This feature does not work with the current control strategy.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
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Re: MS2 3.4.2 - Closed Loop Boost Control
Hi Matt. Maybe I wasn't as clear as I would have liked to have made myself.Matt Cramer wrote:Because the open loop table doesn't specify what boost amount the numbers will actually give you. It uses an initial value table as a feed-forward instead.DisgruntledMotorist wrote:Why doesn't closed loop boost control use the open loop "boost control duty table" as a feed forward term and apply the PID to this value?
This feature does not work with the current control strategy.
I'm familiar with the control strategy, and the initial value function works well.
I believe that closed loop would be much better if the initial value table was actually a feed forward table over the entire rev range of the engine. i.e. if the PID terms were all set to 0, the controller would work just like open loop using the values in the initial value table. And with the PID terms on the duty cycle value would be altered from a calibrated initial duty cycle value, not made up as it goes along.
A maximum percentage authority from the initial value would also make the system much more robust.
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Re: MS2 3.4.2 - Closed Loop Boost Control
That is currently the strategy the MS3 code follows. I am not sure if it can be back ported to MS2 or not.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
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Re: MS2 3.4.2 - Closed Loop Boost Control
As far as I can tell the developers have no desire to continue the development of the ms2. And as I have no desire to buy an ms3 it looks like I'll have to persevere with the ms2 strategy and retune the PID for the different weather conditions of each season.
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Re: MS2 3.4.2 - Closed Loop Boost Control
This is correct. MS2 has been in a "mature" phase for a number of years and no new features are planned.DisgruntledMotorist wrote:As far as I can tell the developers have no desire to continue the development of the ms2.
James
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Re: MS2 3.4.2 - Closed Loop Boost Control
As I understand it MS2 development became problematic as the memory space in the processor had been used up and to add anything means that something has to be removed first.
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Use only these manuals other manuals may cause brain damage or worse.
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Re: MS2 3.4.2 - Closed Loop Boost Control
That does sound familiar, which is a shame.rickb794 wrote:memory space in the processor had been used up and to add anything means that something has to be removed first.
I would happily give up the secondary VE, AFR and Ignition maps, nitrous control and sequential fueling (i don't use and have no intention of using these features) for more robust boost control.