Tony D Posted May 10, 2005 Share Posted May 10, 2005 What is their definition of "Differential Gain" as I'm betting it's somehow the same as Integral. If they don't have some sort of intgral compensation, it's why the pressure-based algorithm will never work. PWM may be the Time-Based "I" in the equation, but it would be a strange way of doing it. Normally PWM is the output. On a PID controller, the OUTPUT is affected by the loops. And I suspect the PWM is changed by P+I+D=O BAH! RESET RATE will be your INTEGRAL! They are using mixed Pneumatic and Electronic Terminology! On a PNEUMATIC controller, you have Porp, Reset, and Anti-Windup Reset (lets not go down this path!) Anyway, What I said about Integral applies to Reset Rate in an inverse fashion. Instead of being Offset from Setpoint/Time you simply ramp up the Reset Rate to make the Porportional Reset close on the target setpoint faster, and use the Differential as you would Integral to close the final "differential gap" once the Porportional controls to the always-present offset point I mentioned earlier! I'll lay money that is how they are controlling it! They are basically all the same, there are only so many things you can do to the thing to control it... Quote Link to comment Share on other sites More sharing options...
Guest Loose_Screws Posted May 10, 2005 Share Posted May 10, 2005 Take a look here http://www.msefi.com/viewtopic.php?t=3155&start=195. The thread is 14 pages long though. They discuss the algorithm and the proposed settings. I suspect you have some very valuable input for them, your help will be appreciated! Quote Link to comment Share on other sites More sharing options...
Tony D Posted May 11, 2005 Share Posted May 11, 2005 I hate to say this, but after the "help" I recieved when it was a Yahoo Groups site, I'm not too keen about going there any more... In any case, I would bend over, as from what I read on EFHAL's post on Pg4, it's a PD controller, and he has a good explanation of what it'd doing there. The Differential Gain setpoint indeed is a derivitave setpoint, and therfore will be VERY touchy and jittery to minute changes. The concept seems to be to use P and then D to slow the response to prevent overshoot. I would read EFHAL's post on Pg 4 GMHeinrik on the same page, specifically the post on dutycycle MattDupis on Pg 8 GMHeinrik on Page 10 For me, giving up the failsafe of INJ2 channel for Boost control doesn't look to be in the cards for me. I know a Z will run on three cylinders and get me home, but not on zero cylinders! Like I said, I like pneumatic boost controllers! LOL Quote Link to comment Share on other sites More sharing options...
Guest Loose_Screws Posted May 11, 2005 Share Posted May 11, 2005 IFor me' date=' giving up the failsafe of INJ2 channel for Boost control doesn't look to be in the cards for me. I know a Z will run on three cylinders and get me home, but not on zero cylinders! Like I said, I like pneumatic boost controllers! LOL[/quote'] My boost control is not connected to INJ2 channel. It is connected directly to pin X4 of the CPU. I have an FET (like I know what that is) installed externally. Either way, I am running only of INJ1 channel to start with. I'll read again and play around with KPA target and tuning the valve more this week or next. Or wait until another code version is released that better supports boost control. Not a whole lot of people running and testing it yet. Quote Link to comment Share on other sites More sharing options...
Guest Loose_Screws Posted May 13, 2005 Share Posted May 13, 2005 OK...I posted my tuning info in the sticky, http://forums.hybridz.org/showthread.php?t=99689, but thought I would add more here. Right now, I have tuned with duty cycle table instead of KPa targets. Without the boost controller, my WG opens at 8psi. I have it tuned to ramp up to 15psi. If I roll on the throttle after downshifting at cruise, it works great, but I cannot just flat foot it or else it will spike about 18 and the overboost protection is set at 16. But if I start from a deadstop (as in launching and banging out the gears), I can do whatever I want and it stays at or below 15psi. So...I am patiently waiting to upgrade to the next version of 'Extra' as I am sure there will be many enhancements to the boost control algorithm. There are far smarter people than I working on it, so I am just figuring out what works for me and being paitent for the next release. Also, I set the lower TPS bins of the duty cycle table low. This allows me to run lower boost just by modulating pedal position. If I want 15psi, I just step down. If I want 10psi, I just keep my foot at or below 75% of travel. Please ask questions and post up your thoughts. If you want to try and setup boost control, I will gladly help anyway I can. Overall, it's pretty simple to wire up, but not the easiest tune, especially by your self. For me, it's tough to find someone crazy enough to ride with me and hold the laptop! Quote Link to comment Share on other sites More sharing options...
mobythevan Posted May 13, 2005 Share Posted May 13, 2005 For me, it's tough to find someone crazy enough to ride with me and hold the laptop! I have my brother drive and I do the tuning. He likes to drive crazy and I'm crazy enough to ride along The progress sounds encouraging on the boost control. Quote Link to comment Share on other sites More sharing options...
bthomp Posted July 1, 2011 Share Posted July 1, 2011 so what do you do when that 14 page link is gone...? Quote Link to comment Share on other sites More sharing options...
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