How to ground a PV inverter?

In general, effective grounding can be achieved with a grounding transformer as shown in Figure 1 (a). If the PV inverter has an internal transformer with the grounded wye to delta configuration, a grounding reactor can be used instead by accessing the neutral point of the inverter transformer.

Do inverters need supplemental grounding?

Effective grounding is a “power system” characteristic, affected by DER. Inverters’ need for supplemental grounding and their responses to ground fault and grid disconnection are significantly different than synchronous machines. 2020 Electric Power Research Institute (EPRI), Inc. All rights reserved.

What is the effective grounding design tool for Solectria inverters?

Solectria provides a spreadsheet ‘Effective Grounding Design Tool for Solectria Inverters’, which conveniently calculates parameters involved in effective grounding projects using Solectria inverters. A sample case study using this spreadsheet is included as a reference which is similar to the example provided in IEEEE P1547.8.

How do you ground a battery inverter?

A grounding wire of 6 AWG must be connected to the grounding terminal on the inverter and connected to a single-point grounding connection wire. If there is no suitable grounding connection point, then the grounding wire from the inverter must be connected to the negative terminal of the battery bank for off-grid systems.

What is effective grounding for inverter-connected der?

Effective Grounding for Inverter-Connected DER: Final Report. EPRI, Palo Alto, CA: 2021. 3002020130. Effective grounding is a characteristic of electric power systems for limiting ground fault overvoltage and considered in coordination of fault current protective devices.

Which transformer should be used for inverter supplemental grounding?

Transformers used for inverter supplemental grounding will have higher impedance than for machines. In case of a Δ secondary of the main interconnect transformer a reactor is likely needed in the high side neutral connection. For inverters the line to neutral connected load can be an effective ground source and should be considered.