Australia (NER / AEMO) ride-through requirements

S5.2.5.1(a1) — “ A schedule 5.2 plant, operating with all its production units in service at any level of active power and while meeting its other performance standards applicable to the voltage ranges specified below, must be capable of supplying or absorbing reactive power continuously at its connection point of the following amounts: (1) for a voltage range that is five percent of nominal voltage above and below the mid-point voltage, both supplying and absorbing an amount at least equal to the product of the maximum active power of the schedule 5.2 plant and 0.395; and (2) for a voltage range from the upper limit of the range described in paragraph (1) to the upper limit established under clause S5.1a.4 without a contingency event: (i) absorbing an amount at least equal to the product of the maximum active power of the schedule 5.2 plant and 0.395; and (ii) supplying an amount at least equal to the amount specified under sub-paragraph (i) at the upper limit of the voltage range in paragraph (1), decreasing linearly to zero at the upper limit established under clause S5.1a.4 without a contingency event ” (National Electricity Rules, Chapter 5, Version 251, accessed 2026-08-10)

S5.2.5.11(i)(1)–(2) — “ (1) the change in power transfer must occur with no delay beyond that required for stable operation, or inherent in the plant controls, once the frequency of the power system as measured at the connection point leaves a deadband around 50 Hz; (2) a schedule 5.2 plant must be capable of setting the deadband and droop within the following ranges: (i) the deadband referred to in subparagraph (1) must be set within the range of 0 to ± 1.0 Hz. Different deadband settings may be applied for a rise or fall in the frequency of the power system as measured at the connection point; and (ii) the droop must be set within the range of 2% to 10%, or such other settings as agreed with the Network Service Provider and AEMO; ” (National Electricity Rules, Chapter 5, Version 251, accessed 2026-08-10)

PFRR Section 3.2.1 (PFCB defined in Section 1.2.1) — “ Subject to section 3.2.2 and any variation or exemption granted in accordance with these PFRR, an Affected Unit must be operated with a deadband equal to the PFCB. For the avoidance of doubt, the Affected Unit’s deadband applies at the connection point. […] PFCB: Primary frequency control band (as at 8 May 2023, it is 49.985 Hz to 50.015 Hz). ” (Primary Frequency Response Requirements (made under NER clause 4.4.2A(a)), accessed 2026-07-28)

PFRR Section 3.3 — “ For all Affected Units, subject to any variation or exemption granted in accordance with these PFRR, droop at the connection point must be set to less than or equal to 5%. The change in frequency is to be measured from the upper or lower limit (as applicable) of the Affected Unit deadband, as shown in Equation 1. ” (Primary Frequency Response Requirements (made under NER clause 4.4.2A(a)), accessed 2026-07-28)

PFRR Section 3.4 — “ Subject to any variation or exemption granted in accordance with these PFRR, an Affected Unit should be capable of achieving a 5% change in active power output within no more than 10 seconds, resulting from a sufficiently large positive or negative step change in frequency greater than the Affected Unit’s deadband and less than or equal to 0.5 Hz. ” (Primary Frequency Response Requirements (made under NER clause 4.4.2A(a)), accessed 2026-07-28)

NER Schedule 5.2, clause S5.2.5.3(b) (automatic access standard), read with S5.2.5.3(a)(1)-(2) — “ The automatic access standard is a schedule 5.2 plant and each of its production units, and (where applicable) synchronous condensers, must remain in continuous uninterrupted operation for frequencies in the following ranges: (1) the lower bound of the extreme frequency excursion tolerance limits to the lower bound of the operational frequency tolerance band for at least the stabilisation time; (2) the lower bound of the operational frequency tolerance band to the lower bound of the normal operating frequency band, for at least the recovery time including any time spent in the range under subparagraph (1); (3) the normal operating frequency band for an indefinite period; (4) the upper bound of the normal operating frequency band to the upper bound of the operational frequency tolerance band, for at least the recovery time including any time spent in the range under subparagraph (5); and (5) the upper bound of the operational frequency tolerance band to the upper bound of the extreme frequency excursion tolerance limits for at least the stabilisation time, unless the rate of change of frequency is outside the range of –4 Hz to 4 Hz per second for more than 0.25 seconds, -3 Hz to 3 Hz per second for more than one second, or such other range as determined by the Reliability Panel from time to time. ” (National Electricity Rules, Chapter 5, Version 251, accessed 2026-08-08)

Frequency operating standard (effective 9 October 2023), Appendix A.1, Table A.1 'Frequency bands' — “ [Table A.1 transcription - rows as printed] normal operating frequency band: Normal (Hz) Mainland/Tasmania (spanned cell) 49.85 – 50.15; Island (Hz) Mainland 49.5 – 50.5, Tasmania 49.0 – 51.0; System restoration (Hz) Mainland 49.5 – 50.5. operating frequency tolerance band: Normal Mainland 49.0 – 51.0, Tasmania 48.0 – 52.0; Island Mainland 49.0 – 51.0, Tasmania 48.0 – 52.0; System restoration Mainland 49.0 – 51.0. extreme frequency excursion tolerance limit: Normal Mainland 47.0 – 52.0, Tasmania 47.0 – 55.0; Island Mainland 47.0 – 52.0, Tasmania 47.0 – 55.0; System restoration Mainland 47.0 – 52.0. ” (Frequency operating standard - Reliability Panel AEMC, effective 9 October 2023, accessed 2026-08-08)

NER Schedule 5.2, clause S5.2.5.4(a) (automatic access standard), read with S5.2.5.4(a0) — “ The automatic access standard is a schedule 5.2 plant and each of its operating production units and synchronous condensers must remain in continuous uninterrupted operation where a power system disturbance external to the plant causes the voltage on one or more phases at the connection point to vary within the following ranges: (1) at least marginally exceeding 130% of nominal voltage for a period of at least 0.02 seconds after T(ov); (2) over 125% up to and including 130% of nominal voltage for a period of at least 0.2 seconds after T(ov); (3) over 120% up to and including 125% of nominal voltage for a period of at least 2 seconds after T(ov); (4) over 115% up to and including 120% of nominal voltage for a period of at least 20 seconds after T(ov); (5) over 110% up to and including 115% of nominal voltage for a period of at least 20 minutes after T(ov); (6) subject to paragraphs (e1) and (e3), 90% to 110% of nominal voltage continuously; (7) below 90% down to and including 80% of nominal voltage for a period of at least 10 seconds after T(uv); and (8) below 80% down to and including 70% of nominal voltage for a period of at least 2 seconds after T(uv). ” (National Electricity Rules, Chapter 5, Version 251, accessed 2026-08-08)

3.8.3A(b)(1) — “ a Market Participant to which this clause 3.8.3A applies must provide an up ramp rate and a down ramp rate to AEMO for each generating unit, scheduled bidirectional unit (in respect of generation and consumption), scheduled network service and/or scheduled load that is: (1) at least the minimum ramp rate for the scheduled resource ” (National Electricity Rules, Version 251 — clause 3.8.3A and Chapter 10 glossary, accessed 2026-07-28)

Chapter 10, definition of 'minimum ramp rate requirement' — “ (a) In relation to a generating unit, bidirectional unit, voluntarily scheduled resource or scheduled load, for each of generation and consumption (as applicable), means the lower of: (1) 3 MW/minute; or (2) 3% of the maximum generation or consumption (as applicable) provided in accordance with clause 3.13.3(b), expressed as MW/minute and rounded down to the nearest whole number except where the result would be zero, in which case the minimum ramp rate requirement is 1 MW/minute. ” (National Electricity Rules — Chapter 10 glossary (M), accessed 2026-07-28)

S5.2.5.3(b) — “ The automatic access standard is a schedule 5.2 plant and each of its production units, and (where applicable) synchronous condensers, must remain in continuous uninterrupted operation for frequencies in the following ranges: […] unless the rate of change of frequency is outside the range of –4 Hz to 4 Hz per second for more than 0.25 seconds, -3 Hz to 3 Hz per second for more than one second, or such other range as determined by the Reliability Panel from time to time. ” (National Electricity Rules, Chapter 5, Version 251, accessed 2026-08-10)

S5.2.5.3(c) — “ unless the rate of change of frequency is outside the range of -2 Hz to 2 Hz per second for more than 0.25 seconds, -1 Hz to 1 Hz per second for more than one second or such other range as determined by the Reliability Panel from time to time. ” (National Electricity Rules, Chapter 5, Version 251, accessed 2026-08-10)

NER Schedule 5.2, clause S5.2.5.5A(f)(1) (automatic access standard - asynchronous plant) — “ Subject to paragraph (h), a schedule 5.2 plant, for disturbances caused by a type of fault described in clause S5.2.5.5(c)(2) to (4), must: (1) to assist the maintenance of power system voltages during the disturbance, have facilities capable of supplying or absorbing at the connection point: (i) positive sequence capacitive reactive current in addition to its pre-disturbance level of at least 4% of the maximum continuous current of all operating asynchronous production units (in the absence of a disturbance) for each 1% reduction of positive sequence voltage at the connection point below the voltage at which the reactive current response commences; (ii) positive sequence inductive reactive current in addition to its pre-disturbance level of at least 6% of the maximum continuous current of all operating asynchronous production units (in the absence of a disturbance) for each 1% increase of positive sequence voltage at the connection point above the relevant percentage of nominal voltage at which the reactive current response commences; and (iii) negative sequence current or equivalent contributions to oppose unbalanced voltages during a disturbance … (within the range of capabilities expressed in this paragraph (f)(1)) to be agreed with the Network Service Provider and AEMO at levels consistent with achieving the control objective ” (National Electricity Rules, Chapter 5, Version 251, accessed 2026-08-08)

NER Schedule 5.2, clause S5.2.5.5A(g)(1)-(2) — “ For the purpose of paragraph (f): (1) the schedule 5.2 plant must commence the required response when or before the voltage reaches the following initiating conditions: (i) for an under-voltage disturbance, 85% of nominal voltage; or (ii) for an over-voltage disturbance, 115% of nominal voltage, with the specific response initiating conditions being agreed with the Network Service Provider and AEMO, consistent with achieving the control objective; and (2) the positive sequence reactive current response opposing the voltage change must commence within 10 milliseconds of the response initiating conditions being met, be adequately controlled and, for a step-like voltage profile at the connection point, have a positive sequence reactive current rise time of no greater than 40 milliseconds. ” (National Electricity Rules, Chapter 5, Version 251, accessed 2026-08-08)