PID O2 control Haltech 1.13

The problem is: if I bring the integral control to 0, then the Proportional control doesn`t work at all, no matter which coefficient had been chosen. The limit of control is 15%, when P = 10, then the O2 correction = 0.2% even if AFR diff>1AFR. If P=1000, the O2 correction = 4,8%, the AFR diff still remains 0,7-0,8 AFR. The main confusing thing is that there is no oscillations with Proportional control enabled. If I turn the P control off and turn I control on, then I have the huge oscillations, like Proportional and Integral coefficients got mixed up. Could somebody confirm that everything in 1.13 firmware is ok?

Thr reply from Haltech:

"Closed-loop control requires both proportional and integral functions in order to work. Proportional controls how fast the system reacts, while integral controls the size of the adjustment. Try setting I to 10, and then experiment with P again."

Can`t understand how it corresponds with manual

Tuning PID Settings

1) Set all Proportional, Integral and Derivative to zero

2) Bring up the Proportional in increments of 5% until you see a small oscillation in the Air Fuel Ratio

3) Bring up the Integral in increments of 5% until you cancel out the oscillation in the Air Fuel Ration. When the Integral part is introduced the Air Fuel ratio will go to the target

Anyone?

Sorry for the slow reply. I found your post quite interesting because the description from Haltech isn't how a conventional PID control algorithm works.

I took the liberty of talking to Scott at Haltech Australia about the situation and he cleared it up. It appears that the older Platinum series ECUs don't employ a completely traditional PID algorithm for their control. The new Elite on the other hand does. I believe it's one of those things where they have something that works on the Platinum and with their current development focus on the Elite, it isn't worth revisiting and potentially breaking a bunch of other code.

Scott said that he was aware you had been emailing with Matt and said he would ask Matt to reply.

I'm unsure how helpful my reply is but I guess this shines some light on why it doesn't respond how you expect.

Tried the Integral coefficient=10. Set up Proportional coefficient=10 - smooth sailing to the target value, the same integral and proportional = 500 - nothing changed, it takes about 30-40 sec. to hit the target. Seems like it has only integral.control working(((

That's interesting. I've never really had any reason to modify the control of the wideband feedback on our Platinum Pro so this isn't an issue I've personally seen. I've seen similar functions in other ECU brands over the years though where the manufacturer has used their own take on a specific function to get the job done. Nothing wrong with that strictly speaking provided it's documented and effective.

The problem is - the factory manual setup procedure is absolutely clear - tune proportional coefficient first and then add some integral control. Now I can't get how it works. BTW there was also derivative control in earlier firmware revisions.Maybe I should downgrade to try the full PID version of control

I agree, it's not entirely helpful when the manual doesn't quite line up with reality. Next time I have the Haltech in our Z I will make sure to have a look at the settings and do some testing for myself.