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Supporting sponsors => Hydra Support and Questions => Topic started by: Canyonfive on April 23, 2013, 07:41:37 PM



Title: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 23, 2013, 07:41:37 PM
My goal is to get the ebc tuning and working. Ill post what i have done so far and ill try all reasonable suggestions. That said I have MBC that works and im trying the EBC for fun so lets leave the mbc vs ebc for another thread.

How this stuff works so far......

The Solenoid is a 3 port PWM based controller. at 0% duty cycle (more on that later) it sends 100% of the air from your boost source to the wastegate. At 100% duty cycle it would send 0% of the air to your wastegate. If the power fails to the ebc all the air will go to your wastegate so it "fails safe".

Easy explanation of duty cycle. In our case its how much air to bleed off. The solenoid is pulsing on and off. Duty cycle is what % of the "cycle" the valve is open not sending air to the wastegate.
(http://arduino.cc/en/uploads/Tutorial/pwm.gif)
 Frequency is how many times a second that happens. See here >> http://www.youtube.com/watch?v=FKKcVR-2a1I (http://www.youtube.com/watch?v=FKKcVR-2a1I)

Sweet webinars!

Helpful hints on boost control plumbing http://www.youtube.com/watch?v=u3AR3D7t3p4&hd=1 (http://www.youtube.com/watch?v=u3AR3D7t3p4&hd=1)
PID parameters explained http://www.youtube.com/watch?v=16Clfh5eBzg&hd=1 (http://www.youtube.com/watch?v=16Clfh5eBzg&hd=1)
PID Tuning http://www.youtube.com/watch?v=SefKQb9y_B4&hd=1 (http://www.youtube.com/watch?v=SefKQb9y_B4&hd=1)
Helpful hints on boost control plumbing http://www.youtube.com/watch?v=u3AR3D7t3p4&hd=1 (http://www.youtube.com/watch?v=u3AR3D7t3p4&hd=1)
Closed loop boost control setup http://www.youtube.com/watch?v=A_EP5AdvuPk (http://www.youtube.com/watch?v=A_EP5AdvuPk)


Next I plugged it in set the max boost and logged. Min duty 0 max 45 (then 47.5) p=200 i=0 d=0 starting: 2500
(http://www.mazda-speed.com/albums/Hydra-EBC/boost_run_1.jpg)

Too little max duty cycle and the EBC never got to the target boost of 8 psi. Increasing the max to 47.5 allowed it to bleed enough air to increase the psi to my target and then some. Boost peaked at 9 then undershot to 6 then overshot to 9 then under to 6.

 My experience with this whole process is that i find that i cant get the whole system to react quick enough. Too much overshoot and undershoot. The system needs to bleed more air as the rpms increase and more quickly after going over my target. Then add duty cycle more quickly after undershooting the target. 

With the duty cycle set too low there is a boost drop off in the upper rpms.

(http://www.mazda-speed.com/albums/Hydra-EBC/boost_run_3_2.jpg)

 I think because at higher rpms there is more of a pressure drop across the intercooler. So a max duty that gives me a crazy boost spike to 13 and fuel cut may not be enough to hold a stable boost to redline. Knowing this I moved the boost source from the nipple on the outlet pipe to after the intercooler in the same pipe i used for my GFB BOV.

(http://www.mazda-speed.com/albums/Hydra-EBC/photo_18.sized.jpg)

1/4" ID pip thread to nipple. I secured with a nut form the electrical section same dia used there.... nothing in hardware.  :laugh:

This seemed to give the flat response i wanted with no boost dropoff.

(http://www.mazda-speed.com/albums/Hydra-EBC/boost_run_2_2.jpg)


Any thoughts on ways to tell the hydra to lower the duty cycle faster (putting more pressure on the wastegate) to better catch the boost. and thus increase it faster to help with the undershoot? This is my main issue currently. On a side note I upped the frequency from 48hx to to 192hz to put my max duty cycle up in the mid 50's instead of around 40 to give it a bigger range to operate. This has resulted in less overshoot and less undershoot. Perhaps even higher will give better response? PID settings?

(http://www.mazda-speed.com/albums/Hydra-EBC/boost_run_4_2.jpg)

All and all its getting better. Now what can I try and Why to improve this?


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 25, 2013, 12:30:55 AM
Here is a photo of moving to 48Hz to 192HZ

(http://www.mazda-speed.com/albums/Hydra-EBC/48hz_to_192hz_2.jpg)


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 25, 2013, 07:42:33 AM
More Testing.... Lots of ups and downs but I think im finally headed in the right direction!

Basically any pid setting i used resulted in garbage. Therefore garbage in garbage out. Meaning my settings not the pid algorithm..

Did you know you can log that pid algorithm in the hydra? Neat stuff.. surprised no one has mentioned it ANYWHERE. Below its the nifty green line

(http://www.mazda-speed.com/albums/Hydra-EBC/100p20i5d192hz_2.jpg)

So no amount of pid worked. In any reasonable combination. Nothing resembled anything I saw anywhere else. So after reading around it seems most people run these valves slower. So I brought mine down from 192HZ to 16HZ which even venting all the air it could (at 100% its still not really 100%; see pwm stuff again to understand why) it wouldn't get up to my target boost. So I then went up to 24hz (other places say 19.5 but there is no option for it here)

Voila.. 100% shows a MAX of 10psi overshooting by 2 psi which is something I can live with during the PID testing. here it is 160p0i0d at 24hz 6th gear pull on a cold night.....

(http://www.mazda-speed.com/albums/Hydra-EBC/24hzworking_2.jpg)

Now someone else please have a go trying PID settings.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: scotty b on April 26, 2013, 05:13:46 AM
So, uh, how much experience do you have with PID controllers?


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 26, 2013, 06:57:25 AM
So, uh, how much experience do you have with PID controllers?

None please tell me what I'm missing. I tried putting all the pid to zero and I still have issue overboosting.   Ill post later what the logs look like.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: scotty b on April 26, 2013, 07:36:19 AM
Here's a real basic rundown.  Think of having 2 lines, one is your program (or ideal) and the other is your actual.  The job of PID is to keep the actual line on top of the program.  In an instant, you are at one point on your actual line, while the computer is looking at one point on the ideal line (the setpoint).  The difference is the error (well, sort of ;) )

P is proportional.  This is your basic gain adjust.  Bigger gain yields a higher basic output, and will be modified by the I and D further.

I is integral.  It's looking at the difference between program and actual, and every so often it integrates (or adds) more error to try and return to setpoint.  Your 'I' value is actually the time constant (IIRC, you should verify in your manual), so a lower value will make it more aggressive.  'I' also contributes to overshoot, since it continues to add error until it crosses the program, and then starts subtracting error (this is called 'wind-up' and can contribute to oscillations).  In a PID, only 'I' will put your actual back onto your program.

D is derivative.  It's a rate-of-change control.  If actual is on program, then the lines just start to diverge, before P or I start to respond, D will start building the error signal, moving the actual toward the program.  This is sometimes called the 'anticipatory' term.

Here's a more in-depth write up on how it works

http://en.wikipedia.org/wiki/PID_controller

I'll bet you can find good user friendly stuff with a google search that will help in practical application.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 26, 2013, 06:46:56 PM
Right. I got that. If it was using the pid where the situation in steady state than that would be no issue. eg; temperature of coolant with a fan.

There are physical limitations in this system that i think need to be programmed to be taken into account.

1) a duty cycle high enough to vent enough air to close wastegate at the upper rpms after the first boost rise causing said rise at 4k to wayyy overboost. (if you look at the second post)

2) Usually it cant add enough air back onto the wastegate quick enough to prevent boost spike (needs to be more predictive? more agressive at 4k less so after)

3) Then pull enough air off to build boost back


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 26, 2013, 06:49:47 PM
Min 0% max 43% 48Hz p0i0d0

(http://www.mazda-speed.com/albums/Hydra-EBC/48hz_Min0_Max43_p0i0d0_2.jpg)


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 26, 2013, 07:16:02 PM
called ingersoll rand supplier. This valve apparently starts to work at something like 20 psi and goes up to 120 psi. They werent helpful
Called their corporate office. Now we are in business so to speak. The black thing at the bottom with 4 dots regulates the size of the orifice. Which dictates response time. So I should be able to adjust it where the duty cycles become more sensitive. Still digesting this new info.



Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 26, 2013, 08:49:10 PM
Sweet now I'm getting somewhere. He was right to suggest left. Haha. One full turn right almost cut off the signal (blew into where the boost source goes). One full turn left (counter clockwise) and I was able to blow significantly more air. 2 turns didnt yield anymore that i could tell. Now there should be more volume for the system to work with. Now it should work. I think that might also explain some of the other issues I was having as well.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 26, 2013, 09:41:36 PM
Not enough air through the solenoid meant that there was not enough air pushing the wastegate open to open it far enough. So even at 0% duty cycle sending 100% of the air to the wastgate the wastegate was not being opened 100%. And the result was a boost spike.

"So the next time we meet, I will not fail. I will go up to the six-fingered man and say, "Hello. My name is Inigo Montoya. You killed my father. Prepare to die." - The Princess Bride. lol thats how I feel.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 26, 2013, 11:40:51 PM
Bingo. Even at 100% Duty Cycle venting I get wastegate pressure. Success!!! Now its just a job of turning it back until i get the max boost i want.

(http://www.mazda-speed.com/albums/Hydra-EBC/192hz_Min0_Max40_p200i0d0_2.jpg)


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: bossman4 on April 27, 2013, 11:48:53 AM
Talk about a one man band!  Go for it.   I had been using the EBC on 2.6 with some spiking and had not tried the 2.7 because I thought Jeremy was going to come up with something .....instead we have .....Canyonfire......


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 28, 2013, 04:29:26 AM
Lol. Canyonfive. And for everyone out there turning it (the black adjustment at the bottom) 3/4 turns counter clockwise will give about 10 psi at 50% duty cycle paving plenty up and down on the duty cycle range for temp variations and the pid to do its work.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: scotty b on April 28, 2013, 06:00:52 AM
Well done, sir, well done.  You should update your sig and maybe do a write-up for this mod (perhaps include all applicable settings to provide a strong starting point), as I don't think many have used an EBC under standalone ecu control.  Perhaps even FM might take interest and offer it as an option in the Big Enchilada...


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: lassi on April 28, 2013, 11:24:27 AM
Well done, sir, well done.  You should update your sig and maybe do a write-up for this mod (perhaps include all applicable settings to provide a strong starting point), as I don't think many have used an EBC under standalone ecu control.  Perhaps even FM might take interest and offer it as an option in the Big Enchilada...

Everybody, exept Hydra owners, has been using their standalones EBC for years... I`m pretty amazed that they finally made it work.
(That even FM gave up on it and sold MBC`s with an ECU which one of the selling features was just that EBC is just sad...)

Interested in what type solenoid you are using? Picture or link to spec of it?


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: bossman4 on April 28, 2013, 01:24:55 PM
It is the Ingersoll Rand Valve that FM sells  http://www.flyinmiata.com/index.php?deptid=&parentid=&stocknumber=07-26500%20%201990-97 (http://www.flyinmiata.com/index.php?deptid=&parentid=&stocknumber=07-26500%20%201990-97).

I don't have the car or the paper instruction located here (they are in Florida) , so I could not provide a link to the Ingersoll Rand web site.  Maybe Canyonfire has a link.....

BTW, I alerted Jeremy about Canyonfire's posts..... I was very close to breaking down and buying the MBC.......

I am anxious to get to Florida to tweak the settings.......


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 29, 2013, 05:26:18 PM
Here is .75 turns left from factory. 6th gear pull p200 i0 d0

(http://www.mazda-speed.com/albums/Hydra-EBC/48hz_75_left_turn_p200_i0_d0_2.jpg)

So left opens and right closes. I thought of a great analogy. Washing your car....

Think of this setting on the valve as how far you turn on the faucet. Then the duty cycles are like using your thumb to increase or decrease the pressure. If the valve is more closed you get a dribble that you cant really wash your car with. You can put you finger on it and it gets higher but you still cant control the water well with your finger because there is not enough volume (not enough water). Now turn up the valve all the way. That you can wash your car with but putting your finger over the stream is too much for your finger to hold. (too much water). We are looking for that sweet spot on the valve where no thumb is nice for getting the water to sheet off the car and lots of thumb is nice for getting stubborn dirt.

This setting controls the volume of air that goes through the valve. To little and there isnt enough volume to fully open the wastegate. Too much and the valve cant bleed enough air to raise boost above wastegate levels.

 



Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 30, 2013, 12:00:28 AM
(http://www.mazda-speed.com/albums/Hydra-EBC/ppjytime.gif)


Success! I have finally gotten the ebc working on the hydra 2.7. Below is how I tuned my closed loop boost control for the hydra ems.

Step 1: Install your solenoid per FM's instructions with one exception. I prefer to use a boost signal source from the pipe i use for my VTA BOV which is right in front of the TB. DO NOT connect it to the Manifold. Brass 1/8" nipple to 1/4 " id pipe thread from the plumbing dept of home depot with a nut from the electric dept. 1/4" conduit nut (I found mine by the lamps parts section in a repair assorted package) The reason I prefer this location is to account for the increasing pressure drop across the intercooler at higher RPMs and the hydra takes the reading from the manifold anyway.

(http://www.mazda-speed.com/albums/Hydra-EBC/photo_18.sized.jpg)

Step 2: Scratch a line indicating the factory position.

(http://www.mazda-speed.com/albums/Hydra-EBC/photo_19.sized.jpg)

Step 3: Rotate the black area 3/4 turn counter clockwise. I used to small hex wrenches (which are also handy for removing pins from the hydra harness)

Step 4: Set your Boost Target table (just press f7 when in your 2.7 software) tuning maps>Boost Control> Boost Target. Remember if you put numbers in here that your car cannot physically reach you will never reach them and only stress your PID system. Mine is 9psi, but lower at 3400.

(http://www.mazda-speed.com/albums/Hydra-EBC/Boost_target.jpg)

Step 5: Adjust your TPS boost trim table. Make 0% your boost target but negative. Press and hold shift on 0% then right arrow until all fields between 0% and 40% are selected. Now press Edit>interpolate rows. This is just a base. Once your Closed loop boost is setup you can adjust this to suit you driving preferences. Below is what mine is.

(http://www.mazda-speed.com/albums/Hydra-EBC/TPSboosttrim.jpg)

Step 6: Set your Maximum Boost Control Duty Cycle Map to 60% across all fields. Tuning Maps> Boost Control> Maximum Boost Control Duty Cycle. Highlight all fields. Press enter then type 60 then enter. Once your system is operational you can make it higher to account for variations in temperature and humidity.

(http://www.mazda-speed.com/albums/Hydra-EBC/MaxSolDutyCycle.jpg)

Step 7: Set your overboost table. Tuning maps> Maximum Boost. Mine is set for 13psi at which point all ignition and fuel cycles are cut. (Rounds down to 12.9) This is your safety if your settings are way off. If you lose power to your FM boost solenoid then it will only flow wastegate boost.

(http://www.mazda-speed.com/albums/Hydra-EBC/overboost.jpg)

Step 8: Set your PID boost control settings as follows. settings>Boost Control  Boost control Threshold 2500 rpm, P-term 30, I-term 0, D-term 5, Boost target scale psi 0, Boost target scale range 15psi. If your running over 15psi then adjust that range higher

(http://www.mazda-speed.com/albums/Hydra-EBC/Boost_control_settings.jpg)

Step 9: Set your datalogging parameters. Slide the bar to 8 channels then type in the fields until you find what you want. I logged RPM's Load (its more accurate than boost but I log that too), Throttle, Boost PID intergration Sum, Base Boost Target, Boost, Boost Solinoid Control Value, Afr. A note: if you cant log then one of your parameter is typed wrong or not selected correctly.

Step 10: Find an appropriate place to test. I used a flat straight long road with a speed limit over 50 and LOTS of places to pull over. A dyno would be safer and as with all hydra tuning having someone you can trust to drive the car while you tune speeds the process up. That said working alone it took about an hour. I drove there with my MBC hooked up and popped the hoses over once I got there that way if I ever want to switch back I just plumb it back in.

DO NOT TEST IF YOU DO NOT HAVE SAFE AFR's AND TIMING AT THE BOOST LEVELS YOU ARE TRYING TO RUN!!

Step 11: Tune your PID. Below are my pulls and my changes. 3rd gear pulls 100% throttle until redline. When I started I just did the pull until I felt the solenoid open up and the subsequent boost drop. If the P is set too high it will oscillate. 

Min 0 Max 60% P=30 I=0 D=5 << which should be your starting settings.

(http://www.mazda-speed.com/albums/Hydra-EBC/48hz_75_left_turn_min0_max_60_p30_i0_d5_2.jpg)

30 was about right but it was overshooting the boost target to 11.4 psi. Adding P will slow the response and lower the overshoot.
Next is Min 0 Max 60% P=45 I=0 D=5

(http://www.mazda-speed.com/albums/Hydra-EBC/48hz_75_left_turn_min0_max_60_p45_i0_d5_3.jpg)

45 was very close and only over shooting to about 10.4. Close enough for now. To reduce the errors over time I is needed. Using I will stabilize the boost and reduce the small errors towards zero. When adding I you will also be decreasing the effectiveness of P.
Next is Min 0 Max 60% P=45 I=5 D=5

(http://www.mazda-speed.com/albums/Hydra-EBC/48hz_75_left_turn_min0_max_60_p45_i5_d5_2.jpg)

Now I have Control over the small errors to redline but because of the addition of I the system is over shooting again as it has reduced the effectiveness of P. So I added a little P.
Next is Min 0 Max 60% P=50 I=5 D=5

(http://www.mazda-speed.com/albums/Hydra-EBC/48hz_75_left_turn_min0_max_60_p50_i5_d5_2.jpg)

This added p cut the overshoot back down and lead to a nice boost curve. Not amazing but working! Once i saw that the Duty Cycle was now not decreasing I saw that the system was stable and that I could increase the Max Duty Cycle.
Next is Min 0 Max 99% P=50 I=5 D=5

(http://www.mazda-speed.com/albums/Hydra-EBC/48hz_75_left_turn_min0_max_100_p50_i5_d5_2.jpg)

This should be a sufficient base to get it working. There is ALOT more tuning to be done in different temperatures and gears. Lets work together to find those and get the most out of the EBC. As people add posts after this one read on as there are likely many refinements to be had. I will post as I try different settings and trims. If anyone wants the logs or anything else feel free to PM me.

 :bannana:


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on April 30, 2013, 04:30:46 AM
The setting worked in the cool of the night. maybe 85 during the day and 60's at night. Ideally i would add a psi in 1st and 2nd, 0 in 3rd, then lower the target 1 psi in 4th and 5th and 2 in 6th. Tried it tonight but it diddnt seem to lower the target in the upper gears. More on it tomorrow.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on May 02, 2013, 12:16:34 AM
So i changed my gear trim to +2,+1,0,-1,-1,-1 and my tps from -14psi at 0tps and 6.7%, then interpolating to 9psi @ 30% TPS. If you want it more NA like then interpolate to 100% TPS. The reason for the -14psi is I cruise at 10inHG so its operating in full open 0% duty when im just cracking the throttle so it runs a little cooler on the freeway.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: bossman4 on May 02, 2013, 01:38:42 AM
Heading to Florida in 2 weeks, so I can play with mine.

Good work.  Jeremy is looking at another solenoid valve, but with your work, not sure it is worth the hassle for Jeremy.   


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on May 12, 2013, 06:15:50 PM
I adjusted my valve because for my car 3/4 turn might not be quite enough. If anyone else does that the pid needs to be retuned.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: schmoo on May 15, 2013, 05:36:14 PM
Awesome.  :mrgreen:


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: schmoo on June 20, 2014, 05:46:13 PM
Guys,

Any progress? I'm sick of MBC and want to go to EBC so that I don't have to make adjustments between cool morning sessions and hot, afternoon, heat-soaked sessions.

Jeremy noted a new solenoid, but he's only got working in open loop.

How are you guys fairing?


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on June 20, 2014, 10:39:31 PM
I havent had time to work on it. I should MAKE time as it would benefit me in autocross. I have the new solenoid but I havent even set it up in open loop.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: fooger03 on May 07, 2015, 03:13:26 AM
Canyon and company,
How are your EBC settings holding up?

I suspect you're not getting steady boost numbers as the days got colder and warmer?

So I've had the Perrin EBCS Pro for about 2 years now.  http://perrinperformance.com/i-14286955-ebcs-pro-universal-electronic-boost-control-solenoid.html

My results have been "no change" from the FM supplied EBCS.  I spent the last month or so (since it's been getting warm) trying to dial it in, high P, low P, high D, low D, 32hz, 256hz, 64hz, changing thresholds, changing min/max solenoid controls, etc.  The results have been identical to anything anyone has tried with the Ingersol valve.  Boost control simply doesn't work well outside a pretty narrow min/max DC chart which doesn't compensate well for changing conditions.

There is a minority report though:

Most of my testing was done on the freeway, in 6th gear, rolling on the throttle to full throttle.  In that situation, the EBC overshoots everytime except when max DC is set low enough to effectively make it open loop.  The "minority report" is this: when still driving down the freeway, I did a 6-4 rev matching downshift before punching the throttle to see what would happen on the logs.  The results were very surprising - a nearly perfect hit with almost no overshoot, and steady boost until I let off the throttle, all while staying well clear of the min/max DC settings. Exactly what the EBC is supposed to do in that situation.

This made me curious, so I tested farther.

With P I D settings set to 2-0-5, and frequency at 64hz, I did a 6th gear freeway roll-on.  The resulting PID Integration sum and PID control % really laid out what was happening in a "clear as day" fashion. The PID control is incorrectly designed to continue to increase the duty cycle until boost exceeds the boost target.

The entire PID calculation is self integrating.

For those without a calculus background, what that means is that the result of each PID calculation is ADDED to the previously calculated result.  The duty cycle of the EBC is never reduced until the boost exceeds the target boost. What is supposed to happen?  Each new PID calculation is supposed to REPLACE the previous PID calculation.

Here is what I witnessed in my 2-0-5 example: Upon application of full throttle, the PID calculation begins at the minimum DC as defined by the EBC Min Duty Cycle table.  It then adds duty cycle slowly, which resulted in wastegate boost pressure, or slightly higher, until the total duty cycle hit about 40%.  At that point, the boost immediately begins to climb, while the EBC duty cycle continues to climb.  Pretty quickly, the EBC passes 75% DC, and by this point, Boost pressure has crossed the target boost line of 12psi.  Only when the boost pressure exceeded the target did the EBC Duty cycles begin to decrease.  By the time the duty cycles decreased enough to slow the increasing boost pressure, the overboost ignition cut was hitting at 15psi.

What *should* have happened in this scenario, was an instantaneous increase in DC for the EBC, followed by an increase in boost pressure.  As the boost pressure increased, the DC of the solenoid should have quickly decreased, long before ever reaching target boost. This represents a PID controller whose P value and total DC decreases as the error (error: difference between boost target and boost pressure) decreases.

Unfortunately, as the boost pressure nears the target boost, the duty cycle of the EBCS does not decrease, is simply increases more slowly as the error is reduced.

The PID calculation is supposed to calculate the result of the P, I, and D values, and then replace the results of the previous PID calculation - instead, it ADDs those two together.

The result is a controller which is not a P-I-D ("Pee Eye Dee") controller, but rather a I-I^2-D ("Eye Eye-Squared Dee") controller.  That is to say that not only does our EBC NOT have "P control" (The most important part of the PID equation), but it provides an "I" control wind-up double whammy.  What we thought of as the P control exhibits "Proportional windup" - which isn't actually a real-thing (It's really integral windup), and our I control experiences "Integral Windup Squared". (The I term is supposed to continue adding to itself, but because both the I and PID terms add to themselves, the I term both adds to itself, and then adds to the sum of it's previous self additions.)

The inherently stabilizing effect of the D term means that it generally doesn't add up, but even at full go, it will never be powerful enough to overcome the wrongly-integrating PID sum which has built up over time.

When I hit the 6-4 rev-matching downshift on the highway, I didn't give the system any "wind-up" time; I effectively allowed the P term to do what it's supposed to do, and the D term properly arrested it from overshooting.

When properly executed, there is never a need for "minimum and maximum Solenoid DC".  Those were put there as band-aids to make a broken system seem fixable, making wind-up less debilitating.

A correct PID system should probably have the following:
1 - A 2D table with "normal" values - or expected EBCS Duty cycle percentages for defined boost targets
2 - Instead of a minimum duty cycle table, a solenoid start, which is the lower threshold for boost at which point the EBC starts accepting PID inputs (for a boost target of 12psi, you might want the EBC to stay at 100% DC until, say 4.5psi)

A P-value is calculated based on boost error versus normal value:
  You might define your "normal" for a boost target of 12psi to be 53% duty cycle.
  Boost error is calculated as boost target minus boost pressure.
  When boost is low (perhaps 5 psi) the controller might be throwing 98% duty cycle at the EBCS.
  As boost approaches 12 psi, your EBCS Duty cycle appoaches 53%.
  If atmospheric conditions dicatate that you only needed 50% DC to make 12 psi of boost, your EBCS slightly overshoots your target and slowly moves back towards the target before settling above your target.
  If atmospheric conditions dictate that you needed more DC, (perhaps 60%), then your EBCS undershoots your boost target, coming to rest below your desired boost.

The I-Value is calculated based on boost error over time, and does not rely on "normal" value:
  While boost is below the boost target, the "I" or "Integral" term, Integrates - that is to say it increases over time.  During spool up, this "integral windup" can have hugely negative side effects in theory, but in practice, the P term actually compensates to remove a great portion of wind-up.
  The intent of the I term is to eliminate error from overshooting/undershooting the normal value.  If the "normal" term is too high, the P value is prone to overshooting.  The I term is what pulls this overshoot back toward the target boost.  The opposite is true if your normal value is too low, the I term pulls the undershoot up towards your target boost.

The I value and the P value have a relationship which is difficult to explain in words, but mathematically simple.  In the case where the "normal" value is too low to reach the boost target in a given atmospheric condition (such as an extremely hot day), the P value will quickly get the EBCS Duty cycle close to the target.  Once at the target, the I value, which has been integrating since PID control was activated begins to add to the EBCS duty cycle, effectively lowering the error.  As the I value decreases the error, the P value provides less input towards the target.  What is important to note is that the change in the I value towards the target will always be more significant than the change in the P value away from the target.  Eventually, the the I value builds until the P-correction becomes zero.  It's hard to explain, but I'll show it in a chart.

First, what a boost pressure versus boost target might look like for a "normal" set a little too low.
(http://i42.photobucket.com/albums/e311/morphout/Boostvtarget_zpso33jyazq.png) (http://s42.photobucket.com/user/morphout/media/Boostvtarget_zpso33jyazq.png.html)

And second, what the I and P correction values would look like (on top of our "normal" value of +53) to get to the target boost.
(http://i42.photobucket.com/albums/e311/morphout/correction_zpshzzrcukr.png) (http://s42.photobucket.com/user/morphout/media/correction_zpshzzrcukr.png.html)
Note that since the EBCS can never exceed 100% Duty cycle, any corrections to more than 100% will simply max out at 100%

Ideally, you want as high an I value as you can get while not seeing noticeable windup during your longest spool ups (6th gear roll on, high altitude, hot weather), and then adjust your P value to achieve the quickest non-overshoot in cold weather, at low altitude, on a downshift. In a perfect world, if calibrated this way, you would never have to worry about the D term - but the stabilizing effect of the D term lets us get away with a pretty decent margin of error, preventing gross overshoots from oversetting our P value, and stabilizing rapid oscillations.

Using the knowledge I have gained through logging and thinking things through, I decided to try my own hand at Hydra EBCS.  I changed my EBCS output from "boost control" to "3D PWM".  For my PWM chart, I used "boost target, final" for the X axis, which calculates all the fancy boost numbers you put in for gear based trim, tps based trim, etc., to get your final boost target.  I then used "boost pressure" for the Y axis.  Wherever I landed on the 3d PWM gave me the difference between boost target and boost pressure.  I then guessed a "Normal" value for the various boost levels represented on the 3d PWM target boost axis.  I put those "normal" numbers in the cells which corresponded with identical boost target and boost pressure.  So a cell which shows a boost target of 12psi, and a boost pressure of 12psi, received my "normal" for 12psi, which I guessed to be about 67% Duty cycle.

From there, I decided on a P value, and through the magic of excel, I determined how much DC to add or subtract from the 67% based on how far away from my target of 12psi I was.  The higher the measured boost, the lower the DC, and vice versa.  At lower throttle levels, I have lower boost targets (TPS Based boost), and therefore my lower normal number is placed in the appropriate cell, and calculations are determined from there.

What I ended up with was a crude "P" controller, which compared my target to my actual to get an error, and that error was added to my "normal" to get proportional control.  It's nowhere near as good as a true PID controller, but it's a zillion times better than an I-I^2-D controller.  Until Hydra puts a real PID function into the Nemesis, I'll have to resort to my crude P controller.  It works...well enough to move onto other things for a little while...


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: fooger03 on May 15, 2015, 07:49:53 PM
After a little bit of playing around, here's a datalog of a 3-gear pull.  Since my 3D PWM map uses "boost target, final", it references TPS-Based boost, and as you can see here, it also references boost-by-gear.

(http://i42.photobucket.com/albums/e311/morphout/3%20gear%20pull_zpsnthdhhni.png) (http://s42.photobucket.com/user/morphout/media/3%20gear%20pull_zpsnthdhhni.png.html)

This is what a P-Controller looks like.  As you can see, it's a hell of a lot better than anything Hydra has available, but you can definitely see where it would benefit both from a D-term (overshoot arrest) and an I term (correction from a resting position towards the boost target position)

As you can see, the boost comes to a resting point below my target in each gear.  To solve this, I could increase my "normals" for each gear, which would raise the resting boost position.  This would work excellent for both the 8 and 10 psi targets of 1st and 2nd gear, but for 3rd gear and up you can see the potential problem with boost overshoot to boost cut.  Additionally, as the weather gets colder (currently 85*), the resting boost will tend to increase anyways because of the atmospheric issues.  The atmospheric differences is why a working "I" term is important, as it will help correct them.

The problem for highway cruising and throttle roll on goes completely away as far as boost overshoot, because there is nothing to "wind up", it's simply proportional control, and the boost builds slowly enough that the P term isn't going to overshoot either.

If anyone else would like to experiment, I can send out my map file (for reference on what to do with the BA05 output, and what the 3D PWM 11 table looks like) and the excel spreadsheet I used to calculate values for the PWM table.  (Insert your anticipated "normal" values for EBC Duty cycle for each boost pressure, tell it what P value to use, and it spits out your table values)


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: fooger03 on May 18, 2015, 09:41:46 PM
More progress made in the last 24 hours.  While looking at a log I realized that even when the Hydra's boost control maps are not used to control the EBC, it still calculates the EBCS duty cycle based on those maps.  This means that I can use the Hydra's "Calculated boost solenoid duty cycle" as an input for a 2d or 3d map.

We already know that I have an apparently successful "P" control.

We also know that Hydra's EBC contol functions as a "I-I^2-D" control.  If I zero out the second term of Hydra's control, what I'm effectively left with is "I-D" control.

Since I can't seem to get the Hydra to do rudimentary math functions on-the-fly, the only way I know of to do them is with a 3D PWM.  On the first axis, I set up my new 3D PWM map to accept the full output of my P control PWM.  On the second axis, I selected the "EBC Duty Cycle" (I-D control) as an input.  Since I only want the I-D control to be able to change my final duty cycle by 20%, I added only 20% of the I-D output to the P output.

Example: If the P term is calling for 45% duty cycle, and the I-D term is calling for 50% duty cycle, the math is 45+(.2*50)=55

Then I went into the Hydra's native EBC maps, set minimum and maximum duty cycle to 0% / 100% at all times.  (If you set maximum to 80%, the term will still "wind-up" to 100%, and when it needs to come down again, it will need to "unwind" from 100 to 80% before you begin to see this term decrease)  Hydra's "P" term is actually our I term, which I set to 25 currently.  Hydra's "I" term is actually an "I-Squared" term, which doesn't belong in a PID control setup - set this to zero.  Finally, Hydra's "D" term is practically a "D" term - unfortunately this D term will have no control over our "P" term.  It is only able to back off of the I-Term, so it's effect will be much smaller than we want it to be.  I maxed this out at 225.

The results:

Smooth pull from 6th gear highway throttle roll on.
6-4 highway downshift hits boost hard and fast.  Can overshoot high by a PSI because of the lack of a solid D term.  Reduced normal fixes the overshoot at the cost of a PSI of boost.  Working to compensate by reducing the proportional correction a bit, which should slow the rise in boost pressure a little bit.

The 1,2,3 pull from a stop is having mixed results.  2nd and 3rd gear hit hard and fast; first gear is causing me problems.

Hydra's EBC does some other funny business that I haven't pinpointed yet.  Usually when you get into boost, the EBC starts at your minimum duty cycle (0% in this case) and begins control from there.  The problem that I've been having is that in first gear, the EBC begins control at 100%.  This means that before I even start building boost, the native EBC control is throwing an extra 20% (100%*.2=20%) DC into my PWM Control equation.

Working with the engine speed trim, I reduced the DC as far as possible (-50%) up to 2550 RPM.  I then set the native EBC control to begin working at 2450 RPM.  This succesfully reduced the "lead in" on a first gear pull to an additional 10% in my final PWM equation, but that's still 10% more DC than I should have as I try to get to my 1st gear boost target of 8psi. It overshoots and doesn't return fast enough to help before I'm shifting into 2nd.  Ideally, I would like to tell the Native PID controller to begin working everything at 50% DC and go up/down from there.  I could effectively reduce my normals all by 10% to compensate, and the "D" term would have more space to work with to arrest overshoot.  Not sure how to make that happen though.

Here are some logs to leave you with.

6th Gear Roll on
Lines From top to bottom:
1. Final PWM EBC Control value (Line 2 + 20% of Line 5)
2. "P value" - proportional control + "Normal"
3. Boost target
4. Measured Boost
5. Hydra's EBC Output being used as "I-D" control
(http://i42.photobucket.com/albums/e311/morphout/20150518%206th%20gear%20roll_zpspkevqcmn.png) (http://s42.photobucket.com/user/morphout/media/20150518%206th%20gear%20roll_zpspkevqcmn.png.html)

6-4 Downshift
1. Final PWM EBC Control value (Line 2 + 20% of Line 5)
2. "P value" - proportional control + "Normal"
3. Boost target - with boost target reduction approaching redline.
4. Measured Boost
5. Hydra's EBC Output being used as "I-D" control
(http://i42.photobucket.com/albums/e311/morphout/20150518%206-4%20drop%20shift_zpslnizstdn.png) (http://s42.photobucket.com/user/morphout/media/20150518%206-4%20drop%20shift_zpslnizstdn.png.html)

1-2-3 Pull (With missed 3rd gear shift)
White Line - Hydra's EBC Control being used as "I-D" control - note the problem in first gear
Yellow Line - Final EBC PWM control (Yellow line affects this by an increase of up to 20%)
Red Line - Target Boost
Blue Line - Measured Boost
If I didn't get a color correct, I'm colorblind, so screw you.
(http://i42.photobucket.com/albums/e311/morphout/20150518%201-2-3_zpscdxtseam.png) (http://s42.photobucket.com/user/morphout/media/20150518%201-2-3_zpscdxtseam.png.html)


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: fooger03 on May 28, 2015, 02:32:50 PM
Note to self (because I can't work on it at the moment, and I need a convenient place to store ideas):
1. increase I-D weight from 20% to 40%.
2. For low RPMs, map the curve of boost available vs. RPM, index boost target to RPM in the boost target table.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: fooger03 on June 01, 2015, 09:30:35 PM
Here are the results of the latest test.  As mentioned in the post above, for low RPMs, I indexed the boost levels attainable at given RPMs - basically this prevents my "I" term from trying to hit 12.0 psi while I'm at 2200 rpm.  I also increased my "I-D" weight from 20% to 40%, this allows my I and D terms to have a greater effect on my solenoid duty cycle.

The first graph is a 6th Gear roll on from ~ 2200 RPM.  As you can see, My boost target is more closely referenced to my actual boost while I'm gaining RPMs to reach my 12psi boost threshold.

Lines, from top to bottom:
Final P-I-D Control Duty Cycle ("Normal" & "P" + 40% of "I" and "D")
"Normal" + "P" Term
Boost Target value (12 PSI Max)
Measured Boost Value
"I" + "D" terms
(http://i42.photobucket.com/albums/e311/morphout/20150601%20-%206th%20gear%20roll_zpsiwdnjb3q.png) (http://s42.photobucket.com/user/morphout/media/20150601%20-%206th%20gear%20roll_zpsiwdnjb3q.png.html)

Second graph is the 6-4 downshift.  You can see the overshoot and associated undershoot oscillation followed by a stabilization at just below the boost target.  As you can see in the bottom line, the "I" term is continuously trying to push the measured boost up to the boost target after the stabilization.  In this case, as the engine RPMs increase more rapidly than in the 6th gear roll example, the air restriction created by the intercooler, throttle body, and associated intake tract also increase more rapidly, which causes a condition eloquently described as "boost sag" - basically the turbo might need to push 12.7psi at 3400 rpm to get 12psi to the intake manifold, but then it might have to pump 15.2psi at 7000 rpm to get the same 12psi to the intake manifold.  You can certainly see that the measured boost never achieves the target boost after the initial oscillation.  In this case, the influence of the "I" term probably needs to be increased so that measured boost oscillates about the target boost line.

Lines, from top to bottom:
Final P-I-D Control Duty Cycle ("Normal" & "P" + 40% of "I" and "D")
"Normal" + "P" Term
Boost Target value (12 PSI Max)
Measured Boost Value
"I" + "D" terms
(http://i42.photobucket.com/albums/e311/morphout/20150601%20-%206-4%20downshift_zpsabuqhqck.png) (http://s42.photobucket.com/user/morphout/media/20150601%20-%206-4%20downshift_zpsabuqhqck.png.html)

In order to increase the influence of the "I" term, I have two options - the first is to again increase the weight % of the "I-D" term, this time to probably 60% weight.  The second option would be to increase Hydra's internal EBC "P" term.  (Which we know from previous posts is actually the "I" term).  Because I also want to gain more influence from the "D" term (arresting overshoot), the correct action is probably to increase the weight of the "I-D" term.  I'll try it at 60% and post up the outcome.

I wasn't able to run a 1-2-3 run today, because my local test track was a little bit damp.  Maybe next time.  I still have no idea how to solve the first gear Native EBC inversion.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: fooger03 on June 01, 2015, 10:20:12 PM
With more understanding, I would like to revise my recommendations to Hydra for correcting the EBC issue.

1.  The PID term must not integrate.  Instead, successive PID calculations must only replace each previous PID calculation, the result of the PID calculation must act on the "Normal" to control boost.
2.  You must come up with a way to provide "normal" values.  In my work, I have provided "Normal" values based on testing.  I have also seen commercially available applications which seem to produce "normal" values where the User inputs the wastegate pressure and the EBC calculates how much % is needed to achieve that pressure.  A learning EBC would be the easiest user-end option, but also the hardest to program.
3.  Eliminate "Minimum EBC Duty Cycle" and "Maximum EBC Duty Cycle".  They are not necessary.
4.  Determine a way to defer the "I" term until measured boost approaches target boost.  My suggestion is to provide a table for the start value of "I" integration, where for different boost target values I can enter different "I" starting points.  An example: If my boost target is 12 psi, I want my I term to integrate at any boost value above 8psi.  The goal is to reduce/eliminate Integral wind-up.  The indexed "boost-target to RPM" table is a method of preventing overshoot, but it is rough, at best.  Effectively, it's using a chainsaw to do the work of a scalpel.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: fooger03 on June 03, 2015, 04:11:23 PM
This is kind of a note for myself, but I'll include background information for others.

When I decided to limit the "weight" of the I-D terms to 20%, the original intent was to reduce integral windup.  Weighting it at 20% was intended to effectively limit integral windup at 20% - as that would be the most that the I-D terms could influence solenoid duty cycle.  After seeing promising results (indicated by little or no windup) by increasing the "weight" to 40% and indexing the RPM-Based boost targets, I believe it may no longer be necessary to reduce the "weight" of the I-D Terms. I anticipate seeing minimal "windup" by increasing the weight to 100%, and if I do see some windup, I can certainly decrease the I term.  The more important thing here is that by increasing the "weight" to 100%, I gain more input from my D term.

For my next iteration, I'll eliminate the weighting and simply add the P and I-D charts together such that their full combined sums will produce the solenoid duty cycle. As an example, if my P term provides an output of 30% DC and my I-D term provides an output of 12%, my solenoid will see a final duty cycle of 42%.

I'll post up results of my next trial set when I get there.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: fooger03 on June 07, 2015, 10:59:57 PM
Had something funny happen when I was trying to turn off hydra's native EBC so that I could get my normals and P value adjusted for a more predictable response.

I set the native "P" value (real I value) to zero, expecting that this would effectively turn off this control.  After a run that didn't go as expected, I went in and investigated and found that the native component was jumping from 0% to 80-90% back and forth, causing uncontrollable oscillations.  My expectation was that with "native P" set to 0, the D wouldn't really have any effect at all because it wouldn't have any value to counter.

Confused, I set the "D" term to zero and tried another run.  On this run, I only achieved wastegate boost, and upon investigation the Hydra was throwing up a boost target of something like 1.2psi.

There some voodoo going on here that I don't quite understand, but in the meantime I'm going to tune my P and normals with my original method (just the single 3D PWM Graph instead of the second combined PWM graph).  Once I'm confident that I can use the P without terribly overshooting, I'll add the I-D control back in and try and tune my I with the D term left to Zero.

After seeing this result, it occurred to me that the high D term could be the cause of the first gear "inversion", causing my I-D term to start at 100% instead of 0%.  Maybe it will shake out if I can tune my P and I values without throwing a Huge D value at it.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on June 10, 2015, 03:47:08 AM
just conjecture, but with the boost targets so close to actual wastegate pressure do you think that it makes it harder to tune? What if the target was 13psi? Would that be easier?


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: fooger03 on June 10, 2015, 11:03:18 AM
my wastegate is somewhere around 5psi - i think that hitting the 12 psi mark is difficult because it's more than twice my wastegate pressure. Still doing some tweaking of normals/p/i/d terms, and I at least imagine I am getting closer.  The only undesireable trait that I have (and still trying to eliminate) is the initial overshoot on the 6-4 downshift (and as such, is likely present on every other high rpm gear shift, up or down).  Today will be the first day that I get back into the D term, as I've had it off for several days while trying to play around with my P term.  I'll see how much of a difference it makes to the product.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on November 08, 2015, 01:58:52 AM
Going back to try some more testing. Anyone want to work together?


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on November 08, 2015, 04:23:38 AM
3rd gear pull P:150 I:0 D:0 using FM's new valve

(http://www.mazda-speed.com/albums/album695/p150i0d03rdgear_001.jpg)

I worked hard to make the Boost target line match how quick the car is capable building boost (I should put the minimum to 100% and see... more testing later) Im curious if anyone else has gotten it to build quicker. I may have a boost leak somewhere.

I do get over shoot when I drop a gear and floor it.

(Manual MBC below)
(http://www.mazda-speed.com/albums/album695/p150i0d03rdgear2.jpg)


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on November 08, 2015, 07:44:02 AM
More reading.....  :o
Im going to try and setup it their way. Why not. The bolded items are different from what I expected.. It seems The EBC isn't designed to control levels less than the wastegate pressure.. So the minimum for us should be about 8psi... and that should start controlling it only a few hundred RPM less than that pressure is reached in sixth gear.

From Hydra,

"Set the boost control threshold RPM to a point that is at least a few hundred RPM below the point at which your turbocharger reached the mechanical wastegate spring pressure in the highest gear you tested. You may need to come back and adjust this value later if you find that the turbocharger can actually exceed your boost target below the threshold engine speed under any conditions. The electronic boost control system will feed a 100% duty cycle to the solenoid valve whenever the engine speed is below the indicated threshold and load is above 160 mmHg (80 kPa). This should keep the wastegate completely closed to improve spool.

The next step is long and tedious, but very critical. We need to determine which boost PID update rate works best with your boost control solenoid and your mechanical boost control system. The majority of setups are going to work best somewhere in the 12-64Hz range, so start at by first testing 32Hz and 48Hz and move in the direction that seems best. To determine the best update rate, we are going to run the electronic boost control system in open loop mode. To do this, set the maximum boost solenoid duty cycle table to zero which will then cause the boost control solenoid duty cycle to be completely controlled by the setting of the minimum boost solenoid duty cycle table. The x-axis of the table will start at the boost pressure indicated by the boost target scale start setting and have a range determine by the boost target scale range setting. What this table defines is the minimum PWM duty cycle that will be delivered to the boost control solenoid depending on the target boost defined by the boost target table with all the boost trims applied. We know that the system cannot control boost below the mechanical boost control system, so any values in the x-axis below that boost should never be used and can be set to zero. For values starting at the mechanical wastegate spring pressure up to the maximum boost that we will control, it is up to us to determine the duty cycle that we need to feed to the boost control solenoid to produce that amount of boost"

So in short we are to have the boost control probably start around 4k and the range to 8-15psi.
Then we set the max Duty Cycle to zero
Then we will up the minimums to reach our desired boost target...but first!



Assume that your mechanical system produces 15 psi. You have set boost target scale start to 15 psi and boost target scale range to 10 psi. We need to start tuning the boost control system by seeing if we can get it to control boost a little above the mechanical range. In most cases, 2 psi (15 kPa) above the mechanical level is a good start. Given that, set the boost target table to 17 psi across the entire engine speed range and set the 17 psi point (and also the points above and below 17 psi to avoid interpolation issues) on the minimum boost solenoid duty cycle table to a starting duty cycle value, say 30%. Also make sure to keep the maximum boost table a few psi above the target boost level you are trying to reach to prevent fuel cut. Now do a pull in 3rd gear and datalog load, engine speed, boost control solenoid duty cycles and anything else you need to make sure that the engine is still running safely at the boost levels you are trying to reach. The datalog should show the solenoid duty cycles at 100% for engine speeds below boost control threshold RPM (assuming you had the foot down on the accelerator at those points) and then at the 30% duty cycle level above the threshold. If boost did not go above the mechanical level, change the minimum duty cycle value to 40% and try again. If the boost was much higher than the 17 psi target, lower the minimum duty cycle and try again. Repeat this experiment until you find the duty cycle value that produces 17 psi across the widest portion of the engine speed range.




Set the max boost to a few psi above where we are testing so we don't run into fuel cut. ( I set it to 15 psi)
The set our boost target level a few psi above wastegate ( I set it to 10psi)
Next guess at Minimum Duty Cycle ( I guessed 30%)
Do a third gear pull with data log.
Increase duty cycle if you didn't reach your target. Decrease if you exceeded you target.
Repeat as necessary to produce the widest range of boost at you target.


If you reach 100% duty cycle then you need to change the refresh rate. Mine is set to 48Hz.. If its too low i suppose you could adjust it(refresh rate) to get to your boost target with around 50% duty cycle.

Repeat as necessary increasing your boost target followed by your minimum duty cycles in 2 psi increments until you reach your target boost pressure....


Next section
"After the process is finished, connect the 2 psi duty cycle point with the most natural line or curve that crosses through the measured 2 psi points. There are a couple problems that you want to spot right away. The first is that the curve or line should move up and to the right without flattening out or suddenly taking a big jump. If the curve does that, or you were not able to hit some parts of the boost target range, then this is probably not a good update rate to use for boost control. If the curve or line looks good, then save a copy of it with a file name that contains the update rate.
 
So Im not sure  is the minumim duty cycle supposed to have a curve?

Next is setting up the max-min boost solenoid duty cycle engine speed trim table

"If you are still reading, then you found a good open loop duty cycle curve, so open that file before performing the next step. Pick a spot in the middle of your boost control range and set the boost target table to it across the engine speed range. Do a pull in 3rd gear and datalog load and engine speed. If the boost stays nearly constant after the turbocharger fully spools to redline, then you don't need to do anything. If the boost drops or creeps upward, then we can make adjustments to the max-min boost solenoid duty cycle engine speed trim table to compensate. If the boost drops towards redline, then add some trim to the engine speed range where the boost drops. If the boost creeps upward towards redline, then remove some duty cycles in that range to help bring the boost down. If you are patient and carefully datalog each experiment and note the effect that your trims are having, you should be able to end up with the same or very nearly the same level of boost across the entire range from the point the turbocharger spools until redline. "


So basically this is how hydra says to setup OPEN loop boost control... (Tuning the PID is not necessary at this stage.) Which is a way I haven't tried yet. Im posting this before I try in case someone want to jump on the bandwagon with me.



 



Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on November 09, 2015, 01:05:41 AM
It actually works... Oh my. I had it all wrong.  ;D

setting it up on open loop with the max at zero and just using the minimum Duty cycle I figured how the map works..

The minimum duty cycle is the duty cycle needed to hit that boost level.. in my case 36% to hit 10psi. then 38% to hit 11 psi. I need to go back and find out what 8psi is. All the other ones below 8 psi don't really matter because that's below wastegate pressure.

Ill post more later.


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on November 09, 2015, 08:55:11 AM

From Left to right. <1-2-3 pull><6th roll on downshift to 5th floored> <6th floored>
(http://www.mazda-speed.com/albums/HydraEBC/1to3_3rd.jpg)

Here are my Min boost table. Max boost table still set at zero. Currently running in open loop boost control.

(http://www.mazda-speed.com/albums/HydraEBC/MinBoostSoleniod.jpg)

So I need to have the solenoid vent air at a 41.57% duty cycle to get 10 psi of boost. Any less and I just get wastegate. For 12psi I need 43.25ish and 44.71 makes 14 or so psi. Just to reiterate this map will look at what you have for a boost target and then use these to know how much air to vent depending on the duty cycle listed. So since my boost target is 10psi the only cell that really matters is the duty cycle under 10psi. As I changed that cell down I found at 41.5 all I got was wastegate and when I changed the 10psi cell to 43.0 I got 12 psi. Thus I just copied over 43.1 over to the 12psi cell. That way if I change my boost target to 12psi the hydra will know how much duty cycle (air) to vent to achieve a certain boost target.

So as an open boost control it works. Its getting late so I have to call it a night. I was slowly working on the Min-Max RPM tirm table to keep a boost level solid until redline. Here is what it is so far. Better but it needs to be steeper to correct for the boost drop off.

(http://www.mazda-speed.com/albums/HydraEBC/MaxMin.jpg)


Missing photos from above
3rd gear pull
(http://www.mazda-speed.com/albums/HydraEBC/p150i0d03rdgear_001.jpg)

Manual (hallman MBC)

(http://www.mazda-speed.com/albums/HydraEBC/p150i0d03rdgear2.jpg)


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: Canyonfive on November 13, 2015, 10:38:12 PM
(http://www.mazda-speed.com/albums/HydraEBC/3rdruns1_4.jpg)

Perfect 3rd gear pull... Decent 1-4.. which I didn't take all the way because I wasn't on the dry lakebed... lol.


It looks like I need a little more max duty cycle to vent enough air to get up to the boost I want. The air temp was rising and I haven't seen what kind of range I need to cover all the temps. I little overshoot getting into 4th so more pid work is needed, but its a lot better than anything before.

My boost threshold is 3200 rpms. P 100 I 10 D 10 Range 5-15psi. Max 15psi

Hopefully I can make some values that are close enough to be used as a default that gets people close enough to finish. Anyone else want to try this?


Title: Re: Hydra 2.7 EBC Settings. Brainstorming, thoughts and help
Post by: redmist on August 30, 2016, 07:55:32 PM
Just finished the FM2 build with EBC. Rock solid right out of the box. Smooth up to 12 psi and stays there. Maybe FM got the bugs worked out.