modelEN12975Curves
Extends from AixLib.Fluid.SolarCollectors.EN12975.
Information
Overview
Simplified model of a photovoltaic thermal collector, which builds upon the solar thermal model. Inputs are outdoor air temperature and solar irradiation. Based on these values and the collector properties from database, this model creates a heat flow to the fluid circuit and an electrical power output.
Concept
The model maps solar collector efficiency based on the equation
and similar for the electrical efficiency a linear approximation is used:
eta=etaEle_zero - mEle * dT/G
Values for the linear and quadratic coefficients for the thermal efficiency as well as the coefficients for the linear approximation are derived from this thesis by Markus Lämmle, p.43 Figure 3.12. The underlying data was validated with the following assumptions:
- solar irradiation G=1000 W/m^2
- windspeed Uwind=3 m/s
- ambient temperature Ta=25 °C
Known Limitations
- No empirical validation has been carried out with the model, only with the parameters in the recrods from the PhD thesis for a single operating point. So, always questions results outside of the operating conditions stated above.
- The parameters for pressure losses and capacities inside the records are based on the solar thermal model, not on the PhD thesis.
- With the standard BaseParameters, this model uses water as working fluid
Parameters
This model is an extension of AixLib.Fluid.Solar.Thermal.SolarThermal. Therefore the parameters can be found in the base model.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| AixLib.Fluid.SolarCollectors.PhotovoltaicThermal.Data.PhotovoltaicThermalBaseDataDefinition | perPVT |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| AixLib.Fluid.SolarCollectors.BaseClasses.EN12975SolarGain | eleGai | Identifies electrical energy prodcued | |
| AixLib.Fluid.SolarCollectors.BaseClasses.EN12975HeatLoss | eleLos | Identifies electrical energy losses due to temperature dependence | |
| Modelica.Blocks.Interfaces.RealOutput | PEle | ||
| Modelica.Blocks.Math.MultiSum | multiSumLos | Sum of all electrical losses | |
| Modelica.Blocks.Math.MultiSum | multiSumGai | Sum of all electrical gains | |
| Modelica.Blocks.Math.Add | add | Sum of all electrical gains and losses | |
| Modelica.Blocks.Nonlinear.Limiter | limiter | Electrical power generation can't be lower than zero |
Revisions
-
January 23, 2024 by Philipp Schmitz and Fabian Wuellhorst:
First implementation. This is for issue 1451.