Explanation of String Inverters

author: SVC ENERGY

2024-04-11

In rooftop solar system, there are three main types: string inverters, microinverters and string inverter power optimizers. String inverters is the most common and traditional types. In this artichle, we give a furtur inctroduction about string inverters.

What is string inverters? How do string inverters work?

Solar string inverters, or central inverters, are devices that convert the energy(DC currents) generated by the solar array to usable AC electricity for home appliances.

It is connected to multiple solar panels that are attached in series to boost the power rating. The conversion is typically performed in the central of solar string inverters.

Advantages of string inverters

Lower costs
Wide MPPT voltage range with flexible configuration
Easy maintenance and replacement
Performs well with no shade

Disadvantages of string inverters

Single point of failure may lead to significant loss of elecricity production
Unable to monitor each panel individually
More expensive to increase solar panels
Not avilable for the roofs with shading issues

String inverters VS. microinverters

Microinverter systems are typically expensive than string inverters as microinverter is individually installed on the back of each panel.

In system with solar string inverters, the conversion of electricity is performed in inverters. But in microinverter systems, it is processed in solar panels.

Microinverter systems provide power production monitoring on each panel individually.

String inverters are the most commonly installed worldwide.

What are string inverter systems

In string inverter systems, solar panels are wired in series. Then connected by a single string to a string inverter. String inverter combines all the direct current from each solar panel at once, transforming to alternating current.

In string inverter power opitimizer systems, the working mode is basically same with the string inverter systems. But with additional opitimizers have installed on each solar panel individually to monitor the performance of solar panel.

What is MPPT in string inverters

Maximum Power Point Tracking (MPPT for short) is an electrical system that enables photovoltaic panels to output more electrical energy by adjusting the working state of electrical modules. It can ensure the energy generated by solar panels is effectively stored in batteries.

When to use string inverters for solar panel systems

String inverters are the most effective and affordable solutions in solar panel systems if there is abundant southern exposure of your roof and without any shading from nearby trees or chimneys. String inverters are standard inverters over decades of use in the residential and commercial solar industry.