What Are The Most Important Things You Need to Know about Solar Micro Inverter?
What is a solar micro inverter? How does a solar micro inverter work? When is it advantageous to use a solar micro inverter in PV applications?
A solar micro inverter converts the direct current of PV module at a time into the alternating current.
The benefit here is that the solar micro inverter can react quickly and well to changing solar radiation conditions and existing solar PV system with solar string inverters could be progressively supplemented with solar micro inverters.
The reasons for the use of Solar Micro Inverter
In conventional solar PV systems, solar power inverters convert the direct current generated by individual solar panels into alternating current.
To be able to achieve the conversion of power peaks, many solar power inverters use a MPP Tracking function: with this function different solar radiation conditions in the individual solar panels can be compensated. However, this technology only works to a certain extent.
If a solar PV system is exposed to frequent change between light and shade, conventional solar power inverters can not provide optimal performance.
In such cases, so-called solar micro inverters are used, which have been specifically developed for small or mobile photovoltaic systems, and can optimize the performance of every individual solar module by the changing of solar radiation.
Differences between Solar Micro Inverter and Solar String Inverter
In principle, the solar micro inverter assumes the same task as conventional string inverters.
While in string inverter systems you use one string inverter per PV string or for the entire PV array (multi string inverter). In the solar micro inverter systems, one is needed for each PV module, its own solar micro inverter.
These are mounted directly behind the solar panels as a single unit and work there independent of each other.
Because of this construction, different shadowing of the solar module and permanent changing radiation conditions are no longer a problem. Modern solar micro inverters react flexibly to solar irradiation of each module.
Further advantages of Solar Micro Inverter systems
Solar micro inverter systems have other advantages:
- An operating solar PV system with micro inverters should not be wired through direct current as in conventional solar PV systems.
- Besides, solar micro inverters are much smaller than the solar string inverters and can also be more easily installed.
- Compared to conventional PV systems, less material is required in micro inverter systems.
Disadvantages in larger systems: failure susceptibility and degree of efficiency
Besides the effective advantages of small PV systems, solar micro inverter systems also have some inconveniences:
- In the large solar PV systems, in which there is a multitude of solar power inverters, a structure should be selected, in which the individual solar micro inverters can be easily removed und replaced in the event of a defect.
- For cost reasons, it is worth to use these inverters only in small PV systems, because the average efficiency level of micro inverters is between 89% und 94%, what is lower than of the high-end inverters with MPP-tracker.
Solar micro inverters are used, especially in small PV systems such as mini PV system in an allotment garden, mountain huts, camping site or in off-grid solar system, which are suited for mobile operation.
To know more about the different types of solar inverter see this article.