What is MPPT Feature in Solar Inverters?

What is the MPPT feature?

Many people working in solar industry knows about MPPT acronym of Maximum Power Point Tracker, but few of them understand correctly, although it is an important feature that helps us increasing solar photovoltaic energy harvest.

Simply put, it is DC to DC converter incorporated inside most of all modern solar photovoltaic inverters that enable maximizing DC energy harvest getting from solar panels at any time during the operation cycle.

How the MPPT feature works?

The basic element is the solar array is the module. We constitute the module as DC source with an internal impedance which will be changed over the day based on level of solar irradiance fallen at the module surface and solar cell temperature. So, the DC solar energy getting from the module is not fixed and its output DC current and voltage are changed over the day as well.

Based on this, MPPT feature importance arises, as the solar inverter internal MPPT circuit will monitor the DC voltage and current all the time and trying to extract maximum power and drive the solar inverter at maximum efficiency point, and this of course will result in high energy yield.

Which one is best: single or dual MPPT?

Dual MPPT inverter is better than single MMPT because it can handle multiple solar strings with different azimuth angle, different tilt angle, different length (voltage), different modules power/ voltage/ manufacturer, and it allows connecting more than 2 strings to the inverter without combiner box.

So, dual MPPT provides higher flexibility, cost saving and higher efficiency with higher harvest as following:

1. When we will be able to connect different strings to the same solar inverter, this means we don’t need to a second inverter nor combiner box, so achieving cost saving.
2. When connecting multiple strings to single MPPT inverter and when one of these strings is subjected to pollution or dust or even shading, this will affect the output of the entire solar array and reduce energy yield. But if we divided the solar array into 2 parts (2 MPPT), then the dusty or shaded string will affect only one MPPT while the other healthy one will still provide its max power, consequently we achieve higher harvest.
3. For dual MPPT inverter, we can monitor each MPPT individually, so detailed monitoring data about energy yield, array status, voltage/ current for each channel can be recognized, so we shall be able to correctly troubleshoot any abnormality at inverter input side.

We think now, you have recognized why understanding MPPT feature is a fast and direct way to achieve more profit from your solar system.