AC coupled inverter: grid-tie energy storage solution

Nowadays, the application of energy storage systems is more and more widespread, especially in recent years, the frequent occurrence of natural disasters and the destruction of the public power grid, having the energy storage system becomes no more than unimportant.

When you want your solar system with battery storage function, it is time to add an AC coupled system and an AC coupled inverter plays a vital role in the grid-tie energy storage system.

What is AC coupled?

AC Coupling is a way in which a solar panel system is interacting with energy storage or battery system. AC coupled system requires two inverters: a common grid-tied solar inverter and a battery-based inverter i.e. AC coupled inverter.

Advantages of AC coupled system:

  •    ★ One of the biggest advantages of AC coupled storage is that it retrofits an existing solar on-grid system to a typical grid-tie energy storage system.
  •    ★ No waste of resources because it keeps the existing solar system and doesn’t need to get rid of the existing equipment and start over.
  •    ★ Easy installation. You just add an AC coupled inverter and battery bank into your solar grid-tie system.

What is an AC-coupled PV system?

It’s adding an AC coupled inverter and battery bank to your existing PV system to retrofit into an energy storage system.

How does AC coupling work

When the sunshine is sufficient enough, the power your existing solar panels generate will be used for home loads. Then, the rest electricity will be stored in the battery bank by AC coupled inverter. If there is excessive power, it will be feedback into the grid to increase the self-consumption rate and reduce the energy bill. 



When the grid is an outage, AC coupled inverter will discharge the battery to support the important loads.


Yes, AC coupled inverter plays an important role in the on-grid energy storage system. And what are the advantages of the AC coupled inverter?

    ☆High performance. It’s the efficiency of charge or discharges with high-frequency isolation up to 96%, current of a battery up to 70A, power of the grid up to 3600W.

   ☆Enhance UPS. When the grid is shut down, the AC coupled inverter starts the UPS function seamless switching within 0.01s with stronger back-up output, and while in parallel, it’s up to 36kW capacity.

   ☆Easy to use. It has 5 schedulable working modes, easy to install and set.

   ☆Remote monitoring and maintenance. It has Intelligent Monitor System, which can realize remote monitoring and upgrade.

How does an AC coupled work?

For explaining how an AC coupled works, there are the list of 5 working modes of an AC coupled inverter below.

AC coupled inverter 5 working modes:

Mode 1: Default mode

The power of solar panels generated is first used to the household load, the rest to charge the battery, excessive feedback into the grid to get the compensation. The priority: loads> battery>grid. This mode applies during the day when the sunlight is enough and solar panels' power is sufficient.


Mode 2: Discharge mode

When the sunset in the afternoon, the PV power is not sufficient enough, then the AC coupled inverter discharges the battery to be used to the home load. This model reduces the amount of electricity taken from the grid and saves bills.


Mode 3: UPS mode

This mode main works in the case of a blackout of the grid. When the grid fails, immediately, the AC coupled inverter discharges the battery power to the important household load using uninterrupted power supply technology which will guarantee the power supply stability and continuity of important loads before you have enabled the UPS function to activate the working mode in adance. When the grid is on, the UPS mode is automatically shut down and continues the previous working mode. 


Mode 4: AC charge mode

This mode is the priority of the battery. The battery can be charged by the grid power by enable relevant functions and make the right settings according to the real demands on the AC charge function via LCD operation, monitoring website or the APP.


Mode 5: Force time mode

In this mode, no matter PV inverter output energy is sufficient or not, the AC coupled inverter charges or discharges the power from or to the grid and time&power&SOC the limit can be set flexibly via LCD operation, monitoring website, or APP. This mode suits situation where the price difference is big. The user can set the charging and discharging time and priority of energy use under “Force time mode”. The user can also choose whether to charge the battery using grid power if the regulations permitted.


If you want to know more about the AC coupled inverter, please go to the website AC coupled inverteror contact us at

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