Broadly, the solar inverters can be categorized in the following types:
Grid Connected Inverters
Grid connected inverters are simply inverters which are connected to the grid. These inverters produce a sine wave that is congruent with the AC waveform produced by the grid.
They allow you to send surplus solar electricity, your system has generated back into the grid.
Grid connected inverters have Anti-islanding feature which allows the inverter to realize the sudden change in system frequency, voltage, rate change of frequency, increase in kW beyond normal levels, or a change in kVAR and shut down the inverter. When the inverter shuts down your system is no longer producing electricity for the safety of the people who will be working on the grid to repair it.
Grid connected inverters are sub categorized as follows:
These inverters are typically used for large scale projects (usually above 250kW). They are huge, have their own rooms with exhaust, etc. They are are cheaper than string inverters & requires low maintenance due to lesser terminations on AC side.
This is the most commonly used solar inverter for homes and business consumers. They are much lighter and resistant to harsh atmospheric
conditions. String inverters are based on modularization, each PV string goes through an inverter, with maximum power tracking peak at the DC terminal, and grid-tied at the AC side.
Micro-inverters are small sized inverters attached to individual solar panels. They use power point tracking, which means essentially if one solar panel is shaded from the sun, the rest of the panels are not impacted. This makes micro inverters somewhat more reliable but the cost is higher than other types.
[Publisher: Solar Power World]
Off – Grid Inverters
Off-grid inverters are used for stand-alone solar power systems i.e. the solar plant is not connected to the electricity grid and therefore requires battery storage.
Off-grid inverter sends power to the appliances in your property & any excess power to your battery bank. When your solar system is not generating power (night time or cloudy days), your appliances will draw power from the batteries.
Unlike grid connected inverters, they do not have the ability to export excess solar electricity into the grid.
These inverters has the capability to charge batteries, draw energy from a battery like an off-grid inverter, as well as export excess energy to the utility grid, like a grid connected inverter.
[Publisher: Admin CER]