heater: 5 sec stabilization time after switching to closed loop

LSU4.2 falls to Underheated state right after switch to closed loop due to rise of sensorEsr (due to applied pump current?)
mck1117 · Mar 22, 2023 · ea16833 · ea16833
1 parent e9343db
commit ea16833
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Showing 2 changed files with 20 additions and 10 deletions.
diff --git a/firmware/heater_control.cpp b/firmware/heater_control.cpp
@@ -68,6 +68,7 @@ static const PWMConfig heaterPwmConfig = {
 
 static constexpr int preheatTimeCounter = HEATER_PREHEAT_TIME / HEATER_CONTROL_PERIOD;
 static constexpr int batteryStabTimeCounter = HEATER_BATTERY_STAB_TIME / HEATER_CONTROL_PERIOD;
+static constexpr int closedLoopStabTimeCounter = HEATER_CLOSED_LOOP_STAB_TIME / HEATER_CONTROL_PERIOD;
 static const struct sensorHeaterParams *heater;
 
 struct heater_state {
@@ -169,6 +170,7 @@ static HeaterState GetNextState(struct heater_state &s, HeaterAllow heaterAllowS
         case HeaterState::WarmupRamp:
             if (sensorEsr < heater->closedLoopThresholdESR)
             {
+                s.timeCounter = closedLoopStabTimeCounter;
                 return HeaterState::ClosedLoop;
             }
             else if (s.timeCounter == 0)
@@ -181,16 +183,23 @@ static HeaterState GetNextState(struct heater_state &s, HeaterAllow heaterAllowS
 
             break;
         case HeaterState::ClosedLoop:
-            // Check that the sensor's ESR is acceptable for normal operation
-            if (sensorEsr < heater->overheatESR)
-            {
-                SetFault(s.ch, Fault::SensorOverheat);
-                return HeaterState::Stopped;
-            }
-            else if (sensorEsr > heater->underheatESR)
-            {
-                SetFault(s.ch, Fault::SensorUnderheat);
-                return HeaterState::Stopped;
+            if (s.timeCounter > 0) {
+                // give some time for stabilization...
+                // looks like heavy ramped Ipump affects sensorEsr measure
+                // and right after switch to closed loop sensorEsr rises above underhead threshold
+                s.timeCounter--;
+            } else {
+                // Check that the sensor's ESR is acceptable for normal operation
+                if (sensorEsr < heater->overheatESR)
+                {
+                    SetFault(s.ch, Fault::SensorOverheat);
+                    return HeaterState::Stopped;
+                }
+                else if (sensorEsr > heater->underheatESR)
+                {
+                    SetFault(s.ch, Fault::SensorUnderheat);
+                    return HeaterState::Stopped;
+                }
             }
 
             break;

diff --git a/firmware/wideband_config.h b/firmware/wideband_config.h
@@ -42,6 +42,7 @@
 
 #define HEATER_PREHEAT_TIME 5000
 #define HEATER_WARMUP_TIMEOUT 60000
+#define HEATER_CLOSED_LOOP_STAB_TIME 5000
 
 #define HEATER_BATTERY_STAB_TIME	3000
 // minimal battery voltage to start heating without CAN command