Views: 82 Author: Summer, Zeoy Publish Time: 2023-10-10 Origin: Site
Why Choose Microinverters?
1. What is a microinverter?
Micro inverter, generally refers to the power less than or equal to 1000W, with module-level MPPT inverter in the photovoltaic power generation system, the full name is micro photovoltaic grid-connected inverter.
The traditional PV inverter connects all the DC power generated by PV modules in series and parallel, and then through the inverter converts the DC power into AC power to access the power grid. The microinverter individually converts the DC power generated by each or a few modules into AC power, and then the AC power will be accessed to the power grid through the parallelization between the micro-inverters.
2. Advantages of Microinverters
The traditional way of connecting solar panels together (in series) introduces many complexities that microinverters can help overcome, including:
High Voltage DC
The high voltage DC power generated by a series solar power system can generate very high-temperature arcs and potential fire risks. This is much less likely to happen as the microinverter converts to 240V AC.
Switchgear
High-voltage DC requires relatively expensive protective switches and fuses. By using AC power, switchgear becomes more common and thus cheaper.
Shading
When solar panels are connected in series, the current in one solar panel affects the current in all the panels because all the solar panels in the string must carry the same current. If one solar panel in a string is shaded and the current in that panel drops, the current in all panels will drop. (Due to "bypass diodes", partially shaded panels can sometimes maintain high current by bypassing the shaded cells, but this depends on the panel design and shade pattern.)
As an example of reducing the current affecting a string: this is an array of 3 modern split solar panels connected to a conventional string inverter. One of the panels gets pooped on by a bird, causing it to reduce its output by 50%, however, it also reduces the output of all the other panels by the same amount.
But by installing a microinverter on each solar panel, the outputs are completely independent. So bird droppings will only affect the soiled panels.
Solar panel mismatch
When solar panels are manufactured, they have slightly different electrical characteristics due to imperfect manufacturing tolerances. When you connect them together, this effect is called "mismatch". Microinverters avoid mismatch by adapting to the unique characteristics of each panel.
MPPT
As with the effects of mismatch, different electrical characteristics produce different maximum power points for each solar panel. The maximum power point is the perfect point to extract the maximum power from the solar panels, so microinverters connected to individual solar panels can better target this point.
Monitoring and fault finding
Almost all inverters have some level of monitoring and fault-finding capability, but they only see the combined output of each solar panel in a series string. Microinverters, however, can monitor each solar panel individually, allowing you to accurately identify what is happening much faster and easier.
Redundancy
If your series string inverter fails, the entire solar array will stop generating power until the failure is repaired. If the microinverter fails, the remaining units can continue to operate, so you should have a more reliable system.
Modularity
Series String Inverters Each inverter can only accept a specific number of solar panels, so it is not always possible to add more panels later. AC solar panels, however, are much easier to add because they are independent of each other.
Orientation
In a series string, all solar panels need to be connected in the same orientation so that they combine to produce the correct voltage to start the inverter at the same time. Since they operate independently, the AC solar panels can be oriented in any direction without interfering with the operation of the other solar panels.