jens/brewpi
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

fix: split inner-loop yi_max clamp to fix HOLD-state windup overshoot

Browse Source 
Renames pid_hold/pid_heat/pid_cool to pid_outer/pid_inner/pid_inner_cool
to match what actually runs when, and splits inner-loop config into
Inner.Heat/Inner.Hold/Inner.Cool so the same PID instance gets a tight
yi_max ceiling only while HOLD drives it, without capping legitimate
1.5 K/min ramps. Fixes the overshoot from docs/overshoot_hold_windup.md
where a cold-water disturbance during HOLD wound up pid_heat's integral
term with no anti-windup engagement, taking ~35s+ to unwind naturally.

Breaking config change: Hold/Heat/Cool -> Outer/Inner.{Heat,Hold,Cool}
in config.json, both .tpl templates, the pid/sud demo scripts, and
replay_sim.py's CLI flags. Adds tests/components/pid/ (stdlib unittest)
covering the Pid clamp/recovery behavior and closed-loop disturbance,
ramp, and HOLD<->HEAT transition cases.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DGQhVQ2Y3yXAQTXhrxVd5u
This commit is contained in:
jens
2026-07-05 21:23:55 +02:00
co-authored by Claude Sonnet 5
parent da832b961e
commit f69d63c31b
17 changed files with 411 additions and 113 deletions
Download Patch File Download Diff File Expand all files Collapse all files
components/pid/temp_controller_fsm.py
+20 -20
View File
@@ -8,9 +8,9 @@ DEFAULT_THRESHOLDS = {
# when COOL meant nothing more than going idle - it's an active state
# with its own PID now, so a threshold this tight relative to a real
# heater's discrete power steps/sensor noise causes the system to
# chatter in and out of it every tick, resetting both pid_hold's and
# pid_cool's integrators each time and never letting either actually
# converge. Symmetric with the others instead.
# chatter in and out of it every tick, resetting both pid_outer's and
# pid_inner_cool's integrators each time and never letting either
# actually converge. Symmetric with the others instead.
"HoldCool": 1.0,
"HeatHold": 1.0,
"HeatCool": 1.0,
@@ -30,14 +30,14 @@ class States(enum.Enum):
class TempControllerFsm:
def __init__(self, dt):
self.pid_hold = Pid(dt)
self.pid_heat = Pid(dt)
self.pid_outer = Pid(dt)
self.pid_inner = Pid(dt)
# Separate gains for ramping down (negative diff) - the actuator
# (e.g. a heat-only Pot/heater) is responsible for clamping the
# resulting negative power to whatever it's actually capable of;
# the controller itself no longer assumes "can't cool" == "must go
# idle".
self.pid_cool = Pid(dt)
self.pid_inner_cool = Pid(dt)
self.thresholds = None
self.state = States.INIT
self.is_startup = True
@@ -80,13 +80,13 @@ class TempControllerFsm:
# which calls this method directly), so an unconditional HOLD
# here gets mistaken for "ramp already reached" and can finish
# a freshly (re-)started step instantly - see SudTask.
# on_process()'s is_holding() check. pid_heat/pid_cool were
# frozen (see process_pid()) and possibly stale for as long as
# we were disabled - start whichever one matters clean rather
# on_process()'s is_holding() check. pid_inner/pid_inner_cool
# were frozen (see process_pid()) and possibly stale for as long
# as we were disabled - start whichever one matters clean rather
# than resuming wherever it last left off.
self.pid_hold.reset()
self.pid_heat.reset()
self.pid_cool.reset()
self.pid_outer.reset()
self.pid_inner.reset()
self.pid_inner_cool.reset()
if diff >= self.thresholds['HoldHeat']:
state_next = States.HEAT
elif diff <= -self.thresholds['HoldCool']:
@@ -96,31 +96,31 @@ class TempControllerFsm:
elif self.state == States.HOLD:
if diff >= self.thresholds['HoldHeat']:
state_next = States.HEAT
# No pid_heat.reset() here — bumpless transfer: carry the
# No pid_inner.reset() here — bumpless transfer: carry the
# hold-phase integral into the new ramp so power doesn't
# drop to near-zero and crawl back up from scratch.
elif diff <= -self.thresholds['HoldCool']:
state_next = States.COOL
self.pid_cool.reset()
self.pid_inner_cool.reset()
elif self.state == States.HEAT:
if diff <= -self.thresholds['HeatCool']:
state_next = States.COOL
self.pid_cool.reset()
self.pid_inner_cool.reset()
elif diff <= self.thresholds['HeatHold']:
state_next = States.HOLD
self.pid_hold.reset()
self.pid_outer.reset()
elif self.state == States.COOL:
if diff >= self.thresholds['CoolHeat']:
state_next = States.HEAT
self.pid_heat.reset()
self.pid_inner.reset()
elif diff >= -self.thresholds['CoolHold']:
state_next = States.HOLD
self.pid_hold.reset()
# pid_heat was frozen during COOL (see process_pid()) -
self.pid_outer.reset()
# pid_inner was frozen during COOL (see process_pid()) -
# resume it clean rather than from whatever it last held
# before COOL took over, which by now may be a stale fit
# for a completely different part of the curve.
self.pid_heat.reset()
self.pid_inner.reset()
if state_next != self.state:
self.state = state_next