This post will work through a simple power electronics problem. An ideal boost converter uses only lossless components (L, C) and no lossy components (R). However, real inductors will have nonzero resistance in its wiring. This copper loss has a strong effect on the converter's ability to boost voltage. This follows the approach of Chapter 3 of Fundamentals of Power Electronics, 2e by Erickson and Maksimović.
The last post showed a simple derivation of the tracking pattern that minimizes the incidence angle of incoming direct irradiance from the sun. There's just one problem -- when the sun is at low elevation, adjacent rows shade each other.
The tracking algorithm used in most commercial PV tracking systems is fairly sophisticated. It has to be able to know where the sun is and how to orient the array to best take advantage of the available sunlight. Let's figure out how they work!
I read a paper recently that turned on a lightbulb about why the PVUSA/ASTM E2848-13 equation is defined the way it is. To quote the paper 1:
The PVUSA method is based on the simplified assumptions that array current is primarily dependent on irradiance and that array voltage is primarily dependent on array temperature, which, in turn is dependent on irradiance, ambient temperature, and wind speed.
The concept of modeling power by modeling current and voltage separately (other than IV-curve modeling, of course) is obvious in hindsight but had never occurred to me before... so let's have some fun and try it out!