solar – solar panel
Synopsis
module generators; class solar { enumeration {SUPPLY_DRIVEN=5, CONSTANT_PF=4, CONSTANT_PQ=2, CONSTANT_V=1, UNKNOWN=0} generator_mode; enumeration {ONLINE=2, OFFLINE=1} generator_status; enumeration {CONCENTRATOR=5, THIN_FILM_GA_AS=4, AMORPHOUS_SILICON=3, MULTI_CRYSTAL_SILICON=2, SINGLE_CRYSTAL_SILICON=1} panel_type; enumeration {DC=1, AC=2} power_type; enumeration {GROUND_MOUNTED=2, ROOF_MOUNTED=1} INSTALLATION_TYPE; enumeration {DEFAULT=1, SOLPOS=2} SOLAR_TILT_MODEL; New in 2.3! enumeration {DEFAULT=1, FLATPLATE=2} SOLAR_POWER_MODEL; New in 2.3! double a_coeff; New in 2.3! double b_coeff; New in 2.3! double dT_coeff; New in 2.3! double T_coeff[%/degC]; New in 2.3! double NOCT[degF]; double Tmodule[degF]; double Tambient[degF]; double wind_speed[mph]; double ambient_temeprature[degF]; double Insolation[W/sf]; double Rinternal[Ohm]; double Rated_Insolation[W/sf]; double Pmax_temp_coeff; double Voc_temp_coeff; complex V_Max[V]; complex Voc_Max[V]; complex Voc[V]; double efficiency[unit]; double area[sf]; double soiling[pu]; New in 2.3! double derating[pu]; New in 2.3! double rated_power[W]; complex P_Out[kW]; complex V_Out[V]; complex I_Out[A]; complex VA_Out[VA]; object weather; double shading_factor[pu]; New in 2.3! double tilt_angle[deg]; New in 2.3! double orientation_azimuth[deg]; New in 2.3! bool latitude_angle_fix; New in 2.3! enumeration {DEFAULT=0,FIXED_AXIS=1,ONE_AXIS=2,TWO_AXIS=3,AZIMUTH_AXIS=4}orientation; New in 2.3! set {S=5, N=4, C=3, B=2, A=1} phases; }
Remarks
A solar panel (also known as solar module or photovoltaic module/panel) is an assembly of solar cells. Solar panels must be connected via a parent inverter.
Properties
Property name | Type | Unit | Description |
---|---|---|---|
generator_mode | enumeration | none | (UNKNOWN,CONSTANT_V,CONSTANT_PQ,CONSTANT_PF,SUPPLY_DRIVEN) Currently solar must operate in SUPPLY_DRIVEN. |
generator_status | enumeration | none | (ONLINE, OFFLINE) |
panel_type | enumeration | none | Uses pre-defined panel technologies.(SINGLE_CRYSTAL_SILICON, MULTI_CRYSTAL_SILICON, AMORPHOUS_SILICON, THIN_FILM_GA_AS, CONCENTRATOR) |
power_type | enumeration | none | Defines whether the connection is AC or DC. Currently not used. |
INSTALLATION_TYPE | enumeration | none | (ROOF_MOUNTED, GROUND_MOUNTED) Currently not used. |
SOLAR_TILT_MODEL | enumeration | none | (DEFAULT, SOLPOS) Defines the tilt model to utilize for tilted array calculations. |
SOLAR_POWER_MODEL | enumeration | none | (DEFAULT, FLATPLATE,PV_CURVE) Defines if the PV array output efficiency should be adjusted for temperatures of the cells using a simple efficiency method, or the SAM simple flat plate efficiency model, or use the PV Curve (DC bus) model. |
a_coeff | double | none | a coefficient for temperature correction forumula New in 2.3! |
b_coeff | double | none | b coefficient for temperature correction forumula New in 2.3! |
dT_coeff | double | %/degC | Temperature difference coefficient for temperature correction forumula New in 2.3! |
T_coeff | double | none | Maximum power temperature coefficient for temperature correction forumula New in 2.3! |
NOCT | double | degF | Nominal operating cell temperature. |
Tmodule | double | degF | Calculated internal temperature of the PV module. |
Tambient | double | degF | Outside air temperature. |
wind_speed | double | mph | Outside wind speed. Currently not used. |
ambient_temperature | double | degF | Current ambient temperature of air |
Insolation | double | W/sf | Solar radiation incident upon the solar panel. |
Rinternal | double | Ohm | Currently not used. |
Rated_Insolation | double | W/sf | Insolation level that the cell is rated for. |
Pmax_temp_coeff | double | Coefficient for the effects of temperature changes on the actual power output. | |
Voc_temp_coeff | double | Coefficient for the effects of temperature changes on the DC terminal voltage. | |
V_Max | complex | V | Defines the maximum operating voltage of the PV module. |
Voc_Max | complex | V | Voc max of the solar module |
Voc | complex | V | Defines the open circuit voltage as specified by the PV manufacturer. |
efficiency | double | unit | Defines the efficiency of power conversion from the solar insolation to DC power. |
area | double | sf | Defines the surface area of the solar module. |
soiling | double | pu | Soiling of the array factor - representing dirt on the array. New in 2.3! |
derating | double | pu | Panel derating to account for manufacturing variances. New in 2.3! |
Rated kVA | double | kVA | Currently not used. |
P_Out | complex | kW | Currently not used. |
V_Out | complex | V | DC voltage passed to the inverter object |
I_Out | complex | A | DC current passed to the inverter object |
VA_Out | complex | VA | Actual power delivered to the inverter |
weather | object | n/a | Reference to a climate object from which temperature, humidity, and solar flux are collected |
shading_factor | double | pu | Shading factor for scaling solar power to the array New in 2.3! |
tilt_angle | double | deg | Tilt angle of PV array New in 2.3! |
orientation_azimuth | double | deg | Facing direction of the PV array New in 2.3! |
latitude_angle_fix | bool | n/a | Fix tilt angle to installation latitude value (latitude comes from climate data) New in 2.3! |
orientation | enumeration | n/a | Type of panel orientation. Types DEFAULT and FIXED_AXIS are currently implemented New in 2.3! |
phases | set | n/a | (A,B,C,N,S) Currently not used. |
pvc_U_oc_V | double | V | Open circuit voltage |
pvc_I_sc_A | double | A | Short circuit current |
pvc_U_m_V | double | V | Voltage at maximum power point |
pvc_I_m_A | double | A | Current at maximum power point |
Default
Parameter | Default value |
---|---|
NOTOC | 118.4 degF |
Tcell | 69.8 degF |
Tambient | 77 degF |
Insolation | 0 |
Rinternal | 0.05 |
Rated_Insolation | 92.902 |
V_Max | 79.34 |
Voc | 91.22 |
Voc_Max | 91.22 |
area | 323 sf |
soiling_factor | 0.95 |
derating_factor | 0.95 |
a_coeff | -2.81 |
b_coeff | -0.0455 |
dT_coeff | 0.0 |
T_coeff | -0.5 %/degC |
efficiency | 0.10 |
generator_mode | SUPPLY_DRIVEN |
generator_status | ONLINE |
panel_type | SINGLE_CRYSTAL_SILICON |
shading_factor | 1 (no shading) |
tilt_angle | 45 deg |
orientation_azimuth | 0 (equator facing) |
latitude_angle_fix | FALSE |
orientation | DEFAULT |
SOLAR_TILT_MODEL | DEFAULT |
SOLAR_POWER_MODEL | DEFAULT |
Example
A minimal model could be created via:
object solar { generator_mode SUPPLY_DRIVEN; generator_status ONLINE; panel_type SINGLE_CRYSTAL_SILICON; efficiency 0.2; parent inverter1; area 2500; }
Model with DC Bus Model
The solar panel, when properly interfaced with an inverter_dyn object in grid-forming mode, will provide DC bus changes and some minor transient detail. A behavioral model of PV cell is adopted here, the advantage of this model is that it only needs parameters of output characteristics of PV cell such as open-circuit voltage (<math>U_{oc}</math>), short-circuit current (<math>I_{sc}</math>), voltage and current at maximum power operating point (<math>U_m</math> and <math>I_m</math>).
The formulas which describe the behavioral model are given as below:
<math>\displaystyle{}I=I_{sc}\left[1-C_1\left(\exp{\frac{U-dU}{C_2U_{oc}}}-1\right)\right]+dI</math> | (1) |
<math>\displaystyle{}C_1=\left(1+\frac{I_m}{I_{sc}}-\right)\exp{\frac{-U_m}{C_2U_{oc}}}</math> | (2) |
<math>\displaystyle{}C_2=\left(\frac{U_m}{U_{oc}}-1\right)\left[\ln{1-\frac{I_m}{I_{sc}}}\right]^{-1}</math> | (3) |
<math>\displaystyle{}dU=-b_1U_{oc}(t-t_{ref})</math> | (4) |
<math>\displaystyle{}dI=I_{sc}\left[a_1\frac{S}{S_{ref}}\left(t-t_{ref}\right)+\left(\frac{S}{S_{ref}}-1\right)\right]</math> | (5) |
Where <math>S_{ref}</math> and <math>t_{ref}</math> are light intensity and temperature in standard environment (<math>S_{ref}=1000\frac{w}{m^2}</math>, <math>t_{ref}=25^{\circ}</math>C), <math>S</math> and <math>t</math> are real light intensity and temperature, <math>a_1</math> and <math>b_1</math> are parameters that used to revise the output characteristics of PV panel in different environment. <math>a_1</math> and <math>b_1</math> are set zero in this instance.
A real PV panel has been modeled according to the formulas above, the output parameters of which are given in Table 1:
Variable | Units | Value |
---|---|---|
<math>\displaystyle{}U_{oc}</math> | V | 1005 |
<math>\displaystyle{}I_{sc}</math> | A | 100 |
<math>\displaystyle{}U_{m}</math> | V | 750 |
<math>\displaystyle{}I_{m}</math> | A | 84 |
In GridLAB-D simulation, the PV panel is modeled as a controllable current source, with the light intensity (<math>S</math>), temperature (<math>t</math>) and voltage of PV panel as inputs. The output of the model is the current of PV panel.
The P-V curve of this PV panel is given in Figure 1, the maximum power is about 1400kW and the voltage at maximum power point is 850V. (<math>t=25^{\circ}C, S=600\frac{w}{m^2}</math>).