fix battery charge u self_sustain rezimu

backend/services/control_exporter.py

@@ -308,6 +308,8 @@ class ControlSetpoints:
     effective_sell_price_czk_kwh: float | None = None
     #: True = reg 108/109 na 0 (PRESERVE – Deye baterii nepoužívá)
     lock_battery: bool = False
+    #: Režim SELF_SUSTAIN: plný rozsah nabíjení/vybíjení na invertoru + zero-export (reg 142) a nízké TOU %.
+    self_sustain_local_use: bool = False
 
 
 @dataclass
@@ -1184,6 +1186,7 @@ def _build_setpoints(mode: OperatingModeInfo, pi: asyncpg.Record | None) -> Cont
             ev1_power_w=0,
             ev2_power_w=0,
             target_soc_pct=None,
+            self_sustain_local_use=True,
         )
 
     if code == "CHARGE_CHEAP":
@@ -1291,8 +1294,14 @@ def _deye_passive_tou_battery_soc_pct(
 
     Jinak zůstane provozní podlaha ``min_soc_percent`` (typicky nízká % → přetok do sítě
     možný dle chování Deye).
+
+    Režim **SELF_SUSTAIN** (``self_sustain_local_use``): vždy ``min_soc_percent`` — nízké
+    TOU drží prioritu „baterie jako buffer“ při plném reg. 108/109 a reg. 142 zero-export;
+    neaplikuje se sem logika 100 % podle ceny (LP se v SELF_SUSTAIN nepoužívá).
     """
     mn = _deye_tou_min_soc_pct(inv)
+    if setpoints.self_sustain_local_use:
+        return mn
 
     bat_w = 0 if setpoints.battery_w is None else int(setpoints.battery_w)
     sell = setpoints.effective_sell_price_czk_kwh
@@ -1311,7 +1320,8 @@ def get_deye_mode(setpoints: ControlSetpoints) -> str:
     SELL only when battery actively discharges for grid export (bat_w < -500
     AND grid_w < -200). Pass-through (PV → grid, battery idle) stays PASSIVE
     with reg 108 = 0 + reg 145 = 1 (solar sell).
-    battery_w=None (SELF_SUSTAIN) → bat_w considered 0 → PASSIVE.
+    battery_w=None (SELF_SUSTAIN) → bat_w considered 0 → PASSIVE; při exportu se ale
+    zapíše plný reg. 108/109 (viz ``self_sustain_local_use`` v ``write_inverter_setpoints``).
     """
     grid_w = int(setpoints.grid_setpoint_w or 0)
     bat_w = 0 if setpoints.battery_w is None else int(setpoints.battery_w)
@@ -1384,6 +1394,11 @@ async def write_inverter_setpoints(
         elif deye_mode == "CHARGE":
             charge_a = battery_watts_to_amps(bat_w, inv.max_charge_a)
             discharge_a = 0
+        elif setpoints_now.self_sustain_local_use:
+            # SELF_SUSTAIN: plný nabíjecí i vybíjecí proud invertoru — přebytek FVE jde do baterie,
+            # reg. 142 = zero export to load/CT (viz selling_mode níže), ne reg. 108 = 0.
+            charge_a = int(inv.max_charge_a)
+            discharge_a = int(inv.max_discharge_a)
         else:
             charge_a = int(inv.max_charge_a) if bat_w > 0 else 0
             discharge_a = int(inv.max_discharge_a)

backend/tests/test_control_exporter_tou.py

@@ -123,6 +123,26 @@ class DeyeTouParamsTests(unittest.TestCase):
         self.assertTrue(g)
         self.assertEqual(s, 95)
 
+    def test_self_sustain_tou_stays_min_soc_even_if_sell_negative(self) -> None:
+        """SELF_SUSTAIN: nízké TOU (min_soc), ne 100 % z negativní vykupní — LP se nepoužívá."""
+        sp = ControlSetpoints(
+            battery_w=None,
+            grid_export_limit=0,
+            ev1_current_a=0,
+            ev2_current_a=0,
+            heat_pump_enable=False,
+            grid_setpoint_w=0,
+            ev1_power_w=0,
+            ev2_power_w=0,
+            target_soc_pct=None,
+            effective_sell_price_czk_kwh=-0.48,
+            self_sustain_local_use=True,
+        )
+        self.assertEqual(get_deye_mode(sp), "PASSIVE")
+        _p, s, g = _deye_tou_params(sp, _inv(min_soc=12, reserve_soc=20))
+        self.assertFalse(g)
+        self.assertEqual(s, 12)
+
     def test_lock_battery_uses_min_soc(self) -> None:
         sp = ControlSetpoints(
             battery_w=0,