add converge check that h_comp_out_new changed

Author: Yujie Xu

src/EnergyPlus/HVACVariableRefrigerantFlow.cc

@@ -11123,6 +11123,8 @@ void VRFCondenserEquipment::CalcVRFCondenser_FluidTCtrl(EnergyPlusData &state)
     Real64 h_comp_in_new;            // enthalpy of refrigerant at compressor inlet (new) [kJ/kg]
     Real64 h_comp_out;               // enthalpy of refrigerant at compressor outlet [kJ/kg]
     Real64 h_comp_out_new;           // enthalpy of refrigerant at compressor outlet (new) [kJ/kg]
+    Real64 h_comp_out_new_prev;      // previous value of h_comp_out_new
+    Real64 tol_h_comp_out_new;       // tolerance of h_comp_out_new change
     Real64 m_air;                    // OU coil air mass flow rate [kg/s]
     Real64 m_ref_IU_cond;            // mass flow rate of Refrigerant through IU condensers [kg/s]
     Real64 m_ref_IU_cond_i;          // mass flow rate of Refrigerant through an individual IU condenser [kg/s]
@@ -11214,6 +11216,8 @@ void VRFCondenserEquipment::CalcVRFCondenser_FluidTCtrl(EnergyPlusData &state)
     RefPLow = this->refrig->PsLowPresValue;   // Low Pressure Value for Ps (>0.0)
     RefPHigh = this->refrig->PsHighPresValue; // High Pressure Value for Ps (max in tables)
 
+    tol_h_comp_out_new = 1e-10;
+
     // sum loads on TU coils
     for (NumTU = 1; NumTU <= NumTUInList; ++NumTU) {
         TU_CoolingLoad += state.dataHVACVarRefFlow->TerminalUnitList(TUListNum).TotalCoolLoad(NumTU);
@@ -11924,10 +11928,11 @@ void VRFCondenserEquipment::CalcVRFCondenser_FluidTCtrl(EnergyPlusData &state)
         }
 
         //* Update h_comp_out in iteration (Label230)
+        h_comp_out_new_prev = h_comp_out_new;
         h_comp_out_new = Ncomp / (m_ref_IU_evap + m_ref_OU_evap) + h_comp_in;
 
         if ((std::abs(h_comp_out - h_comp_out_new) > Tolerance * h_comp_out) && (h_IU_cond_in < h_IU_cond_in_up) &&
-            (h_IU_cond_in_low < h_IU_cond_in)) {
+            (h_IU_cond_in_low < h_IU_cond_in) && std::abs(h_comp_out_new - h_comp_out_new_prev) > tol_h_comp_out_new) {
             Real64 h_IU_cond_in_old = h_IU_cond_in;
             if (h_comp_out < h_comp_out_new) {
                 h_IU_cond_in = h_IU_cond_in + 0.1 * (h_IU_cond_in_up - h_IU_cond_in_low);