DPL: Solar inverter max increase calculcation is less strict, respects overscaling configuration and more

include/PowerLimiterInverter.h

@@ -93,6 +93,8 @@ class PowerLimiterInverter {
     void setTargetPowerState(bool enable) { _oTargetPowerState = enable; }
     void setExpectedOutputAcWatts(uint16_t power) { _expectedOutputAcWatts = power; }
 
+    static char mpptName(MpptNum_t mppt);
+
     // copied to avoid races with web UI
     PowerLimiterInverterConfig _config;
 

include/PowerLimiterSolarInverter.h

@@ -17,5 +17,4 @@ class PowerLimiterSolarInverter : public PowerLimiterInverter {
 private:
     uint16_t scaleLimit(uint16_t expectedOutputWatts);
     void setAcOutput(uint16_t expectedOutputWatts) final;
-    static char mpptName(MpptNum_t mppt);
 };

src/PowerLimiterInverter.cpp

@@ -349,4 +349,44 @@ void PowerLimiterInverter::debug() const
         (_oTargetPowerState.has_value()?(*_oTargetPowerState?"production":"standby"):"unchanged"),
         getUpdateTimeouts()
     );
+
+    MessageOutput.printf("    MPPTs AC power:");
+
+    auto pStats = _spInverter->Statistics();
+    float inverterEfficiencyFactor = pStats->getChannelFieldValue(TYPE_INV, CH0, FLD_EFF) / 100;
+    std::vector<MpptNum_t> dcMppts = _spInverter->getMppts();
+
+    for (auto& m : dcMppts) {
+        float mpptPowerAC = 0.0;
+        std::vector<ChannelNum_t> mpptChnls = _spInverter->getChannelsDCByMppt(m);
+
+        for (auto& c : mpptChnls) {
+            mpptPowerAC += pStats->getChannelFieldValue(TYPE_DC, c, FLD_PDC) * inverterEfficiencyFactor;
+        }
+
+        MessageOutput.printf(" %c: %.0f W",
+                mpptName(m), mpptPowerAC);
+    }
+
+    MessageOutput.printf("\r\n");
+}
+
+char PowerLimiterInverter::mpptName(MpptNum_t mppt)
+{
+    switch (mppt) {
+        case MpptNum_t::MPPT_A:
+            return 'a';
+
+        case MpptNum_t::MPPT_B:
+            return 'b';
+
+        case MpptNum_t::MPPT_C:
+            return 'c';
+
+        case MpptNum_t::MPPT_D:
+            return 'd';
+
+        default:
+            return '?';
+    }
 }

src/PowerLimiterSolarInverter.cpp

@@ -27,14 +27,31 @@ uint16_t PowerLimiterSolarInverter::getMaxIncreaseWatts() const
         return maxTotalIncrease;
     }
 
+    // when the current limit is less than 15% of the max power of the inverter
+    // the output will not match the limit as the inverters are not able to work
+    // with those low limits. In this case we assume that the inverter is able to
+    // provide more power and we return the maximum possible increase.
+    // thanks spcqike for creating a table that can be found here:
+    // https://github.com/hoylabs/OpenDTU-OnBattery/issues/1087#issuecomment-2216787552
+    if (getCurrentLimitWatts() < getInverterMaxPowerWatts() * 0.15) { return maxTotalIncrease; }
+
     auto pStats = _spInverter->Statistics();
     std::vector<MpptNum_t> dcMppts = _spInverter->getMppts();
     size_t dcTotalMppts = dcMppts.size();
 
     float inverterEfficiencyFactor = pStats->getChannelFieldValue(TYPE_INV, CH0, FLD_EFF) / 100;
 
-    // 98% of the expected power is good enough
-    auto expectedAcPowerPerMppt = (getCurrentLimitWatts() / dcTotalMppts) * 0.98;
+    // with 97% we are a bit less strict than when we scale the limit
+    auto expectedPowerPercentage = 0.97;
+
+    // use the scaling threshold as the expected power percentage if lower,
+    // but only when overscaling is enabled and the inverter does not support PDL
+    if (_config.UseOverscaling && !_spInverter->supportsPowerDistributionLogic()) {
+        expectedPowerPercentage = std::min(expectedPowerPercentage, static_cast<float>(_config.ScalingThreshold) / 100.0);
+    }
+
+    // x% of the expected power is good enough
+    auto expectedAcPowerPerMppt = (getCurrentLimitWatts() / dcTotalMppts) * expectedPowerPercentage;
 
     size_t dcNonShadedMppts = 0;
     auto nonShadedMpptACPowerSum = 0.0;
@@ -227,23 +244,3 @@ void PowerLimiterSolarInverter::setAcOutput(uint16_t expectedOutputWatts)
     setTargetPowerLimitWatts(scaleLimit(expectedOutputWatts));
     setTargetPowerState(true);
 }
-
-char PowerLimiterSolarInverter::mpptName(MpptNum_t mppt)
-{
-    switch (mppt) {
-        case MpptNum_t::MPPT_A:
-            return 'a';
-
-        case MpptNum_t::MPPT_B:
-            return 'b';
-
-        case MpptNum_t::MPPT_C:
-            return 'c';
-
-        case MpptNum_t::MPPT_D:
-            return 'd';
-
-        default:
-            return '?';
-    }
-}