The AEMC has provided the Reliability Panel with Terms of Reference to review the Frequency Operating Standard (FOS) that applies in the national electricity market. The terms of reference for this review of the FOS were published on 30 March 2017.
This review will investigate the appropriateness of the settings in the FOS as the market transforms from conventional synchronous generators, towards non-synchronous generation such as wind and solar panels.
This review of the FOS follows the Emergency Frequency Control Schemes rule change which raises the following issues relevant to the review:
the appropriateness of the requirements in the FOS relating to multiple contingency events
the incorporation of the new contingency event classification for “protected events” into the FOS.
The Panel will publish an issues paper in mid-2017 followed by a draft report later in the year for consultation.
The terms of reference require that the Panel completes this review by 22 December 2017.
One of AEMO's key obligations under the National Electricity Rules (NER) is to maintain the power system in a secure operating state. This includes keeping system frequency within the normal operating frequency band.
The frequency requirements that AEMO must meet are set out in the Frequency Operating Standard (FOS), which is defined in the rules and determined by the Reliability Panel.
The FOS includes defined frequency bands and timeframes in which the system frequency must be restored to these bands following different events, such as the failure of a transmission line or separation of a region from the rest of the national electricity market (NEM). These requirements then inform how AEMO operates the power system, including through applying constraints to the dispatch of generation or procuring ancillary services.
The FOS currently consists of two separate standards: one for the mainland NEM, and one for Tasmania. This reflects the different physical and market characteristics of the Tasmanian region as opposed to the mainland NEM.
The frequency operating standard for Tasmania was last reviewed and determined by the Reliability Panel on 18 December 2008. The frequency operating standard for the mainland was last reviewed and determined by the Reliability Panel on 16 April 2009.