NS194
Inverter Energy System
NS194: Inverter Energy Systems
This document outlines the requirements for connection of Inverter Energy Systems (IES) to the Ausgrid network.
Scope
This document outlines the requirements for connection of Inverter Energy Systems (IES) to the Ausgrid network. IES are generators that are able to connect in parallel to Ausgrid’s network which use power electronics to generate the required AC waveform. IES systems typically have solar (PV) panels and/or chemical batteries connected as a DC supply source for the inverter. However, they may also connect other DC power sources such as hydrogen fuel cells or asynchronous AC generators driven by wind turbines, hydro or fossil fuel power sources.
This standard is primarily focussed on export and generation control and limits, additional anti-islanding protection requirements, along with select other technical requirements which are related to protection, or are often implemented using the same equipment (e.g. voltage and power quality control). There are differing requirements depending on IES rated capacity and total IES capacity.
It also covers earthing requirements for IES and establishes technical review and approval requirements based on IES rated capacity.
The requirements for IES short circuit protection systems are not covered in this standard. Further information can be found in AS/NZS 3000, Service and Installation Rules of NSW, and the National Electricity Rules.
Standby IES which use a ‘break before make’ transfer system and hence will never operate in parallel with the Ausgrid’s network are covered in Section 8.3 of the Service and Installation Rules of NSW to which there are no additional requirements as a result of this standard. Standalone IES power system also have no further requirements in this standard since they do not interact with the Ausgrid network.
Where AS/NZS 4777 is the applicable technical standard for Inverter Energy Systems, these AS/NZS 4777 requirements apply in full other than where a limited variation or additional requirement is specified by this NS194.