That's fundamentally how a control system is supposed to work. The open loop control is basically a "feed forward" to the PID/Closed loop control. Without a well calibrated open loop system a PID controller won't result in very stable control...johnb wrote: Tue Apr 26, 2022 8:02 pm It suspect it's more complicated than than just using a PID. The KLR uses a combination of open loop and PID control. One of the things on my list is to disable each one in turn and find out which one matters more. But I strongly suspect that it's the open loop control that does most of the work, and the PID controller is for fine tuning. It could do all the work on it's own, but it might be slow.
That's a common method to fine tune a closed loop control. Get close with your open loop maps/tables, find some stable PID gains, then use the error to go back and adjust the open loop parameters as necessary. Sort of like fuel trim "learning" in some EFI control.johnb wrote: Tue Apr 26, 2022 8:02 pm I've never used an aftermarket boost controller, so maybe they have this feature, but what I would consider if I was designing one is to use the PID control option, and the use that to gather the duty cycle data, and then use that data for open loop maps. Of course those maps have to change if you change anything in the engine, but as long as it stays the same it would be more responsive (in theory).
