Energy storage inverter pre-charging

What happens when DC voltage is applied to an energy storage inverter?

When DC voltage is applied to the input of an energy storage inverter, large inrush currents will occur as the DC bus capacitance will initially appear as a short. Without the use of a pre-charge unit, these inrush currents can damage the batteries, the capacitors and IGBTs.

Does a PV battery need a pre-charge?

In most PV applications, pre-charge of the Inverter DC bus capacitance is not required due to the I-V characteristic of the PV cell. The inherent current limit of the PV array will limit the current inrush on the inverter bus to acceptable levels. Batteries have extremely high short circuit capacities.

Can a hybrid energy storage system improve power reliability?

This white paper presents a hybrid energy storage system designed to enhance power reliability and address future energy demands. It proposes a hybrid inverter suitable for both on-grid and off-grid systems, allowing consumers to choose between Intermediate bus and Multiport architectures while minimizing grid impact.

Why do batteries need a DC pre-charge unit?

Batteries have extremely high short circuit capacities. This results in them being able to provide an extremely high peak inrush current to the inverter DC bus. This inrush current needs to be mitigated with the use of DC pre-charge assemblies. Dynapower’s CPS and DPS product lines come with integrated pre-charge units.