How Many Types of Solar Inverters Are There?

Understanding solar inverter

A solar inverter is a device that converts direct current (DC) from a solar battery into alternating current (AC). "Inverter" refers to the process of changing the electrical properties of the current from DC to AC. The working circuit of a solar inverter must be a full-bridge circuit, which changes the load and polarity of the current through a series of filtering and modulation processes to achieve the desired outcome for the user. This is the main function of a solar inverter.

The common solar power generation system in our daily life consists of four parts: a solar cell panel, a charging controller, a solar inverter, and a battery. The solar cell panel provides DC power by converting solar energy into electrical energy; the charging controller mainly controls the energy transformation; the solar inverter converts the DC power into AC power for storing in the battery, which stores the AC power for our use. It can be said that the solar inverter is the key device in the entire solar power generation system. Without the inverter, there would be no AC power for us to use.

Classification of solar inverters

Solar inverters can be divided into three main types:

Stand-alone inverters are used in isolated systems, where the solar inverter extracts DC energy from the battery charged by the photovoltaic array. Many stand-alone inverters also integrate battery chargers to supplement the battery when there is an AC power source. They are typically not connected to the grid in any way and do not require islanding protection.

Grid-tie inverters are designed to match the phase of the sine wave provided by the utility company for safety reasons, and are designed to shut down automatically in the event of a power outage. During a utility outage, they do not provide backup power.

Battery backup inverters are specialized inverters designed to draw energy from batteries, manage battery charge with vehicle charging equipment, and output excess energy to the grid. These inverters can provide AC energy to selected loads during utility outages and require islanding protection.

Smart hybrid inverters can manage photovoltaic arrays, battery storage, and the grid, all directly coupled to the unit. These modern all-in-one systems typically have high versatility for use in grid-tie, stand-alone, or backup applications, but their main function is to reduce self-consumption by using stored energy.