From d3f90f205495a9710cd6c8de0eba3f4b5a0fb130 Mon Sep 17 00:00:00 2001
From: Matthew Kennedy <matthewkennedy@outlook.com>
Date: Fri, 9 Jul 2021 23:15:24 -0700
Subject: [PATCH] heater fiddling

---
 firmware/heater_control.cpp | 29 ++++++++++++++++++++++++-----
 firmware/wideband_config.h  |  2 +-
 2 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/firmware/heater_control.cpp b/firmware/heater_control.cpp
index 562db4c..7391e64 100644
--- a/firmware/heater_control.cpp
+++ b/firmware/heater_control.cpp
@@ -34,8 +34,8 @@ static HeaterState GetNextState(HeaterState state, float sensorEsr)
             if (timeCounter <= 0 || sensorEsr < HEATER_CLOSED_LOOP_THRESHOLD_ESR)
             {
                 // If enough time has elapsed, start the ramp
-                // Start the ramp at 50% duty - ~6-7 volts
-                rampDuty = 0.5f;
+                // Start the ramp at 30% duty - ~3-4 volts
+                rampDuty = 0.3f;
 
                 // Next phase times out at 15 seconds
                 timeCounter = HEATER_WARMUP_TIMEOUT / HEATER_CONTROL_PERIOD;
@@ -78,7 +78,21 @@ static HeaterState GetNextState(HeaterState state, float sensorEsr)
     return state;
 }
 
-static Pid heaterPid(0.003f, 0.005f, 0.0005f, 0.6f, HEATER_CONTROL_PERIOD);
+// oscillates at 0.04 kP
+
+//static Pid heaterPid(0.04f,0, 0, 0.6f, HEATER_CONTROL_PERIOD);
+
+// "no overshoot" PID
+//static Pid heaterPid(0.008f, 0.0288f, 0.0015f, 0.6f, HEATER_CONTROL_PERIOD);
+
+// PI
+//static Pid heaterPid(0.02f, 0.0576f, 0.0015f, 0.6f, HEATER_CONTROL_PERIOD);
+
+// rusefi ETB autotune
+//static Pid heaterPid(0.014f, 0.018f, 0.0018f, 0.6f, HEATER_CONTROL_PERIOD);
+
+// rusefi ETB autotune with more PD
+static Pid heaterPid(0.02f, 0.018f, 0.003f, 0.6f, HEATER_CONTROL_PERIOD);
 
 static float GetDutyForState(HeaterState state, float heaterEsr)
 {
@@ -88,8 +102,8 @@ static float GetDutyForState(HeaterState state, float heaterEsr)
         case HeaterState::WarmupRamp:
             if (rampDuty < 0.75f)
             {
-                // 0.4 volt per second, divided by battery voltage and update rate
-                constexpr float rampRateVoltPerSecond = 0.4f;
+                // 0.3 volt per second, divided by battery voltage and update rate
+                constexpr float rampRateVoltPerSecond = 0.3f;
                 constexpr float heaterFrequency = 1000.0f / HEATER_CONTROL_PERIOD;
                 rampDuty += ((rampRateVoltPerSecond / 14) / heaterFrequency);
             }
@@ -125,6 +139,11 @@ static void HeaterThread(void*)
         state = GetNextState(state, heaterEsr);
         float duty = GetDutyForState(state, heaterEsr);
 
+        // Limit to 80% duty
+        if (duty > 0.8) {
+            duty = 0.8;
+        }
+
         // Pipe the output to the heater driver
         heaterPwm.SetDuty(duty);
 
diff --git a/firmware/wideband_config.h b/firmware/wideband_config.h
index 5aa58cf..3f556cb 100644
--- a/firmware/wideband_config.h
+++ b/firmware/wideband_config.h
@@ -46,5 +46,5 @@
 
 #define HEATER_CLOSED_LOOP_THRESHOLD_ESR 2000
 #define HEATER_TARGET_ESR 300
-#define HEATER_OVERHEAT_ESR 200
+#define HEATER_OVERHEAT_ESR 150
 #define HEATER_UNDERHEAT_ESR 3000