Answer:

The term DC-microgrid is used for Ferroamp's direct current (DC) grid built in each EnergyHub installation.

The DC-microgrid is generated by the EnergyHub, which charges the DC grid to a voltage of 760V (+/- 380V) during startup, which is the operating voltage of the EnergyHub system. When the voltage on the DC grid is charged, the Solar String Optimizers (SSOs) and Energy Storage Optimizers (ESOs) start up, activating solar power production and the battery.

The components in the DC-microgrid then communicate with each other using both Power Line Communication (PLC) and voltage level in the network, also known as Droop Control.

PLC is used to send data to the components, and the system's control is based on the voltage level configured in the EnergyCloud.

Example:

If we have configured the battery to charge when we start exporting solar power to the grid, the following occurs when our solar production exceeds the property's consumption:

• The EnergyHub measures with current transformers that the property starts exporting electricity over the main fuse.
• The EnergyHub raises the voltage in the DC grid above 760V.
• The ESO responds to the rising voltage by starting to charge the battery and thus drawing power from the DC grid to lower the voltage back to 760V.

If we have configured the battery to discharge when we start importing electricity from the grid, the following occurs when our property consumption exceeds solar production:

• The EnergyHub measures with current transformers that the property starts importing electricity over the main fuse.
• The EnergyHub lowers the voltage in the DC grid below 760V.
• The ESO responds to the decreasing voltage by starting a discharge of the battery and thus supplying power to the DC grid to raise the voltage back to 760V.

If our solar panels produce more power than what the EnergyHub can convert to alternating current (AC), the following occurs:

• The voltage on the DC grid rises above 760V.
• The SSOs respond to the rising voltage by attempting to lower production to lower the voltage back to 760V.

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