From cc55d951ef518643f9b66ce80b86138cda2b0ce7 Mon Sep 17 00:00:00 2001
From: Ben Pirt <ben@pirt.co.uk>
Date: Sat, 2 Dec 2023 10:07:56 +0000
Subject: [PATCH] WIP - Dynamically adjust the charge current to avoid
 over-voltage

---
 battery/battery_pack.py |  7 -------
 bms/bms.py              | 17 ++++++++++-------
 2 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/battery/battery_pack.py b/battery/battery_pack.py
index ec68bcc..e3985d0 100644
--- a/battery/battery_pack.py
+++ b/battery/battery_pack.py
@@ -122,13 +122,6 @@ def cell_voltage_difference(self) -> float:
             return max((module.cell_voltage_difference for module in self.modules))
         return 0.0
 
-    def should_charge(self, current_state: bool) -> bool:
-        if current_state is True:
-            return self.high_cell_voltage < self._config.cell_high_voltage_setpoint
-        else:
-            return self.high_cell_voltage < (
-                self._config.cell_high_voltage_setpoint - self._config.charge_hysteresis_voltage)
-
     def should_discharge(self, current_state: bool) -> bool:
         if current_state is True:
             return self.low_cell_voltage > self._config.cell_low_voltage_setpoint
diff --git a/bms/bms.py b/bms/bms.py
index 858987e..7b70b0f 100644
--- a/bms/bms.py
+++ b/bms/bms.py
@@ -30,6 +30,7 @@ def __init__(self, battery_pack: BatteryPack, config: Config, current_sensor: Op
         self.__discharging_enabled = True
         self.__charging_timer = get_interval()
         self.__charging_timer.set(self.__config.charge_hysteresis_time)
+        self.__charge_current = self.__config.max_charge_current
         self.__discharging_timer = get_interval()
         self.__discharging_timer.set(self.__config.charge_hysteresis_time)
         self.__wdt: Optional[WDT] = None
@@ -73,17 +74,19 @@ def current(self) -> float:
 
     @property
     def charge_current_setpoint(self) -> float:
-        self.__charging_enabled = self.battery_pack.should_charge(self.__charging_enabled)
-        if self.__charging_enabled is True:
-            if self.__charging_timer.ready:
-                return self.__config.max_charge_current
+        voltage_difference = self.battery_pack.high_cell_voltage - \
+            self.__config.cell_high_voltage_setpoint
+        if voltage_difference > 0:
+            self.__charge_current = self.current * 0.9
         else:
-            self.__charging_timer.reset()
-        return 0
+            self.__charge_current = min(
+                self.__charge_current * 1.1, self.__config.max_charge_current)
+        return self.__charge_current
 
     @property
     def discharge_current_setpoint(self) -> float:
-        self.__discharging_enabled = self.battery_pack.should_discharge(self.__discharging_enabled)
+        self.__discharging_enabled = self.battery_pack.should_discharge(
+            self.__discharging_enabled)
         if self.__discharging_enabled is True:
             if self.__discharging_timer.ready:
                 return self.__config.max_discharge_current