During our April Controllers & Inverters Overview webinar, one of the attendees asked How often do Morningstar MPPT controllers evaluate and determine the maximum power point on the IV curve that the controller should operate at? Below is the answer to that question:

Morningstar MPPT controllers evaluate the maximum power point (also referred to as “sweeping the IV curve”) at 3 minute intervals.  The controller does this by slightly altering its resistance and subsequently calculating the product of the resulting amperage and voltage.  Morningstar’s TrakStar technology evaluates and determines the maximum power point in a fraction of a second, which is extremely fast compared to competitor MPPT technologies.  The evaluation is so fast that any disruptions with power input to charge batteries are negligible, as opposed to the power losses that some competitor MPPT controllers incur during sweeping.

Moreover, it is important to note that Morningstar’s TrakStar technology evaluates ALL the points on the IV curve when it performs a sweep, not just points near the previously determined power point.  This ensures that the true maximum power point is established in cases where multiple high points exist on the IV curve.

In order to get the best results from your MPPT controller it is recommended that all the modules that make up your solar array are uniform (e.g. the same brand and model number). Otherwise, if your array is composed of different model types and specifications, this can confuse the MPPT controller’s tracking algorithm. Other factors that can disrupt PV array performance and power point tracking include inadvertent shading, and dust and debris on the modules.