7/31/2019 For Solar Panel Two Diode Mdl

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First of all you should gather the information from your solar panel datasheet/manual:1)Short Circuit Current2)Maximum Power Point Current @ STC3)Open Circuit Voltage4)Maximum Power Point Voltage @ STC

5)Thermal coefficient of Short Circuit Current6)Thermal coefficient of Open Circuit VoltageTo model the solar panel there is a function of the form I=f(V).If you take a look to the math expression you would see some constants and twovariables (the global solar irradiation and ambient temperature) which play a role in thefunction.The constants are determined from the above information. Use the file "twoDiode.mdl"to calculate them.What you have now is the I-V characteristic of the solar panel which is depended fromsolar irradiation and ambient temperature. The I-V characteristic of your solar panel isimplemented in the file "solarpanel.mdl". So you double click the model to define the

constants and then you see three inputs. 1)global irradiation 2)temperature 3)Voltage.And you get the current.For example you keep global irradiation and temperature steady and change thevoltage from 0 to the open circuit voltage and you get the nice I-V curve that you wouldsee in your datasheet or manual of your solar panel product.If you want to connect this box with some resistance or a more complex circuit youwould get the electrical behaviour of your solar panel.

But in case you are only interested in power I have also uploaded the file"solarpanel_power.mdl" which has only two inputs: 1) global irradiation and 2)temperature. The solar panel is supposed to be working at Maximum Power Pointinstantaneously all of the time.

Ok now let's see why we got in all this trouble.Let's say that your panel has a peak performance of 15%. But noone really cares aboutSTC conditions. In case your country is a bit north maybe there not any time in the yearwhere solar irradiation is 1000W/m^2 so your solar panel would never reach thisperformance. What you really care is the mean performance for your own territory.This is easy. You simple go to this website: http://www.soda-is.com/You get fill a form of where you live and in what inclination you have installed yourpanels and you get the irradiation that the surface of your panels receive in a hourlybasis for all the year. Yes you get 8760 values. And another 8760 values for thetemperature.

There you have to play a little bit with Matlab to extract the values from the excel. Usethe xlsread(). Don;t worry you only do this once unless you move to a different area orchange the inclination of your panels.Time to get the results.Use the irradiation and temperature values as inputs and let the Simulink simulate yoursolar panel for a whole year. As output is the power of your panel at each time. Try tointegrate that (use the integration block) and you get the energy that came out of yoursolar panel in a year period. The energy that was received is the integration of solar

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7/31/2019 For Solar Panel Two Diode Mdl

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