South Korea (KEPCO) ride-through requirements
Low-voltage ride-through, High-voltage ride-through, Frequency ride-through for South Korea. Every breakpoint below is read from the code itself, and where a point was taken off a published figure rather than stated in the clause, the section under that chart says so — an envelope the source only partly defines.
What is the low-voltage ride-through envelope for South Korea (KEPCO)?
The plant must ride through for any voltage that stays on or above this envelope. The envelope holds 0 pu from t = 0 to 150 ms; then 0 pu from 150 ms to 151 ms; then 0.5 pu from 151 ms to 160 ms; then 0.7 pu from 160 ms to 1.5 s; then 0.9 pu from 1.5 s onward — the last band the envelope defines, with no stated end time.
Every breakpoint is stated in the clause cited below.
Applies to DER at the distribution PCC, connection classes from LV to 22.9 kV
| From | To | Voltage | Between the points |
|---|---|---|---|
| 0 | 150 ms | 0 pu | Held flat |
| 150 ms | 151 ms | 0 pu | Held flat |
| 151 ms | 160 ms | 0.5 pu | Held flat |
| 160 ms | 1.5 s | 0.7 pu | Held flat |
| 1.5 s | no stated end | 0.9 pu | Held flat |
The clause this came from
KEPCO 분산형전원 배전계통 연계 기술기준 (업무표준 H0-배전-기준-0015, 개정 14, 2021-06-01), 제24조 (계통연계 유지 / Fault Ride-Through), <표 2.7> 비정상 전압에 대한 운전지속시간: V<50 → 0.15 s; 50<=V<70 → 0.16 s; 70<=V<90 → 1.5 s; 110<V<120 → 0.2 s; V>=120 → none. (Trip table <표 2.4> is separate.).
What is the high-voltage ride-through envelope for South Korea (KEPCO)?
The plant must ride through for any voltage that stays on or below this envelope. The envelope holds 1.2 pu from t = 0 to 200 ms; then 1.1 pu from 200 ms onward — the last band the envelope defines, with no stated end time.
Every breakpoint is stated in the clause cited below.
Applies to DER at the distribution PCC, connection classes from LV to 22.9 kV
| From | To | Voltage | Between the points |
|---|---|---|---|
| 0 | 200 ms | 1.2 pu | Held flat |
| 200 ms | no stated end | 1.1 pu | Held flat |
The clause this came from
KEPCO 분산형전원 배전계통 연계 기술기준 (개정 14, 2021-06-01), <표 2.7>: 110 < V < 120 → 운전지속시간 0.2초; V >= 120 → '-' (no ride-through). Complementary trip table <표 2.4>: V>=120 → 분리시간 0.16 s.
What is the frequency ride-through envelope for South Korea (KEPCO)?
The plant must ride through between the upper and lower bands. The upper (over-frequency) band holds 61.5 Hz from t = 0 onward — the last band the envelope defines, with no stated end time. The lower (under-frequency) band holds 57 Hz from t = 0 to 299 s; then 57.5 Hz from 299 s onward — the last band the envelope defines, with no stated end time.
Covers only the part of the envelope the source defines.
Applies to DER at the distribution PCC, connection classes from LV to 22.9 kV
Upper limit
| From | To | Frequency | Between the points |
|---|---|---|---|
| 0 | no stated end | 61.5 Hz | Held flat |
Lower limit
| From | To | Frequency | Between the points |
|---|---|---|---|
| 0 | 299 s | 57 Hz | Held flat |
| 299 s | no stated end | 57.5 Hz | Held flat |
The clause this came from
KEPCO 분산형전원 배전계통 연계 기술기준 (개정 14, 2021-06-01), <표 2.8> 비정상 주파수에 대한 운전지속시간: f > 61.5 → '-'; f < 57.5 → 299초; f < 57.0 → '-'; and <표 2.5> 비정상 주파수에 대한 분산형전원 분리시간: f > 61.5 → 0.16초; f < 57.5 → 300초; f < 57.0 → 0.16초. High boundary is a single level (no over-frequency ride-through granted); low boundary floor 57.0 Hz is the bottom edge of the 299 s band.
Operating requirements beyond the envelopes.
The envelopes above are what South Korea (KEPCO) demands during a disturbance. The rows below are the same regime’s operating and fault-response requirements — reactive capability, frequency response, continuous operating range, ramp rate and fault-current injection — each researched from the document its own row cites, separately from the plotted corpus. Every row carries its clause and a verbatim quote, so you can check it the same way.
| Requirement | What the code states | Clause |
|---|---|---|
| Transmission: reactive capability 0.9 lagging – 0.95 leading; renewables P-Q envelope ±33% Reactive capability | All generators: supply reactive power over 0.9 lagging to 0.95 leading power factor, on the basis of rated active output (MW) at rated voltage. Wind/PV/fuel-cell plants: P-Q envelope figure requires Q of ±33% (figure axis values; basis rated active power, absorb and supply) for active output between 20% and 100% of Pn, tapering below 20% Main requirement (별표8 3.가) binds every generation customer under a transmission-facility use contract — generation-scoped; storage never named as the subject of a requirement (전기저장장치 occurs zero times in the 이용규정; the string "ESS" appears only in hybrid-renewable telemetry tables, contract templates and planning forms, none imposing a duty and none in 별표8), so a transmission-connected BESS is bound via its treatment as a generation customer. The figure-based envelope (별표6 4.나.4)가)) binds 풍력, 태양광 및 연료전지 발전기 (wind, PV, fuel-cell) only; 조력 (tidal) is set at 0.95 lagging–0.95 leading and 'other renewable generators' are referred back to 별표8. A standalone BESS is not a 신재생발전기 under 별표6 3.3) (definition tied to the New & Renewable Energy Act), so for BESS the 별표8 0.9/0.95 range is the operative requirement. Measured at rated voltage; 별표6 5)가) additionally requires renewables to operate continuously within the voltage-maintenance ranges 765±5%, 345±5%, 154±10%, 22.9 kV −9.2%/+3.9%. Charge direction: 별표7 [일반접속조건] 2.가 (printed p. 100) requires 부하역률 ≥ 0.9 of every transmission customer (제31조①), which reaches a BESS while charging. The 별표6 5)가) voltage-maintenance ranges are cited from that provision but are not carried in the quoted text. | 별표8 [발전접속조건] 3. 기술적 요구 사항, 가. 발전기 무효전력, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed pp. 102–103) + 별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 4)가)① and figure <유효전력 출력에 따른 무효전력 공급범위>, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 85) |
The clauses this row cites별표8 [발전접속조건] 3. 기술적 요구 사항, 가. 발전기 무효전력, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed pp. 102–103) — “ 가. 발전기 무효전력 정격 전압에서 정격출력(㎿) 기준으로 지상역률 0.9에서 진상역률 0.95 범위 내에서 무효전력을 공급할 수 있는 성능 유지 ” Translation: “ ga. Generator reactive power: maintain the capability to supply reactive power within the range from 0.9 lagging power factor to 0.95 leading power factor, on the basis of rated output (MW) at rated voltage ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) 별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 4)가)① and figure <유효전력 출력에 따른 무효전력 공급범위>, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 85) — “ ① 운전전압 범위 내에서 아래와 같이 유효전력 출력에 따른 무효전력 공급능력을 갖추어야 함 ” Translation: “ (1) Within the operating-voltage range, [the wind, PV and fuel-cell generator] shall have the reactive-power supply capability according to active-power output as shown below ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) | ||
| Distribution DER (ESS included by definition): power factor ≥90%, no leading PF into the grid Reactive capability | DER power factor is to be maintained at 90% or higher as a rule; as a rule the DER must not present a leading power factor as seen from the grid side; for reverse-flow DER, lower and upper PF limits may be set by agreement between the customer and KEPCO where technically needed for voltage control Binds storage explicitly: 제3조 제1호 다목 defines 양방향 분산형전원 (bidirectional DER) including 전기저장장치 (ESS) per 전기설비기술기준 제3조 제1항 제28호, so a distribution-connected BESS is a 분산형전원 and this article reaches it by name — this KEPCO internal standard (H0-배전-기준-0015) is the instrument governing a distribution-connected BESS, operating under 송배전용전기설비이용규정 제39조 per its 제1조. Modal fidelity: both sentences use '원칙으로 한다' ('as a rule / in principle'), and the PF band is negotiable by agreement — not an absolute shall. Measured at the DER; no separate charge-mode reactive requirement is stated. | 제15조(전기품질) ②항 제1호–제2호, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) + 제3조(용어정의) 제1호 다목 ①, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) |
The clauses this row cites제15조(전기품질) ②항 제1호–제2호, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) — “ 1. 분산형전원의 역률은 90% 이상으로 유지함을 원칙으로 한다. 다만, 역송병렬로 연계하는 경우로서 연계계통의 전압상승 및 강하를 방지하기 위하여 기술적으로 필요하다고 평가되는 경우에는 연계계통의 전압을 적절하게 유지할 수 있도록 분산형전원 역률의 하한값과 상한값을 고객과 한전이 협의하여야 정할 수 있다. 2. 분산형전원의 역률은 계통 측에서 볼 때 진상역률(분산형전원 측에서 볼 때 지상역률)이 되지 않도록 함을 원칙으로 한다. ” Translation: “ 1. As a rule, the power factor of the distributed energy resource shall be maintained at 90% or higher. However, in the case of reverse-flow parallel interconnection, where it is assessed as technically necessary to prevent voltage rise and drop on the interconnected system, the lower and upper limits of the DER power factor may be set by consultation between the customer and KEPCO so that the voltage of the interconnected system can be maintained appropriately. 2. As a rule, the power factor of the DER shall not become leading as seen from the grid side (lagging as seen from the DER side). ” (분산형전원 배전계통 연계 기술기준 (H0-배전-기준-0015, 제20차 개정), accessed 2026-08-09) 제3조(용어정의) 제1호 다목 ①, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) — “ 다. 양방향 분산형전원은 아래와 같이 전기를 저장하거나 공급할 수 있는 시스템을 말한다. ① 전기저장장치(ESS : Energy Storage System) 전기설비기술기준 제3조 제1항 제28호의 규정에 의한 전기를 저장하거나 공급할 수 있는 시스템을 말한다. ” Translation: “ da. A bidirectional distributed energy resource means a system that can store or supply electricity as follows: (1) Electricity storage system (ESS: Energy Storage System): a system that can store or supply electricity as prescribed in Article 3, Paragraph 1, Item 28 of the Technical Standards for Electrical Installations. ” (분산형전원 배전계통 연계 기술기준 (H0-배전-기준-0015, 제20차 개정), accessed 2026-08-09) | ||
| Transmission: frequency-following droop 3.0–5.0%, deadband max 0.06% (renewable inverters); governor droop 2.5–7.5% (synchronous ≥20 MVA) Frequency response | Wind/PV/fuel-cell inverters: frequency-following operation in over- and under-frequency with settable speed-regulation (droop) 3.0–5.0% and deadband max 0.06%. Synchronous generators ≥20 MVA: governor permanent droop 2.5%–7.5%, speed deadband ±36 mHz The inverter requirement (별표6 4.나.6)나)) binds 풍력, 태양광 및 연료전지 발전기 인버터 (wind, PV, fuel-cell inverters) connecting to the transmission system — 전기저장장치 is not named, so a standalone transmission-connected BESS is not directly captured by it; the governor requirement (별표8 3.카) is scoped to 동기발전기 (synchronous generators) ≥20 MVA and likewise does not reach an inverter-based BESS. At KEPCO-instrument level this leaves no explicit droop requirement binding a standalone BESS; frequency-regulation performance for dispatched/market resources sits in KPX's 전력시장운영규칙 (separate instrument). No activation/full-response time and no sustain duration are stated in either provision. '속도조정률' is defined in 별표6 3.10) as the ratio of frequency change to output change in percent (i.e., droop). | 별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 6)나) 주파수 조정, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 86) + 별표8 [발전접속조건] 3. 기술적 요구 사항, 카. 조속기 성능 : 20MVA 이상의 동기발전기, 1)–2), 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 104) |
The clauses this row cites별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 6)나) 주파수 조정, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 86) — “ 나) 주파수 조정 풍력, 태양광 및 연료전지 발전기 인버터는 과·저주파수 시 주파수 추종 운전이 가능해야 하며, 주파수 변화에 따라 다음과 같이 정정할 수 있는 제어 성능을 구비해야 함 ① 주파수 변화에 따른 속도조정률 : 3.0~5.0% ② 불감대 : 최대 0.06% 이내 ” Translation: “ na) Frequency adjustment: Wind, photovoltaic and fuel-cell generator inverters shall be capable of frequency-following operation during over- and under-frequency, and shall be equipped with control performance settable according to frequency change as follows: (1) speed-regulation rate (droop) according to frequency change: 3.0–5.0% (2) deadband: within a maximum of 0.06% ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) 별표8 [발전접속조건] 3. 기술적 요구 사항, 카. 조속기 성능 : 20MVA 이상의 동기발전기, 1)–2), 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 104) — “ 1) 조속기는 2.5%~7.5% 범위의 영구 속도조정율 특성을 갖추어야 함 2) 속도 응동 불감대(dead band)는 ±36m㎐ 이하이어야 함 ” Translation: “ 1) The governor shall have a permanent speed-regulation (droop) characteristic in the range 2.5%–7.5% 2) The speed-response deadband shall be ±36 mHz or less ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) | ||
| Distribution DER: Frequency/Watt and ramp-rate functions required — but Article 25 is suspended Frequency response | No droop, deadband or response-time parameters are prescribed for distribution DER; Article 25 requires grid-support DER to possess the <표 3.3> function set — including 주파수-유효전력 제어 (Frequency/Watt: control active power according to frequency deviation) and 출력 램프율 (N-RAMP: control rate-of-change of output in normal operation) — but application of Article 25 is suspended until KEPCO announces a separate effective date 제25조 ① addresses inverter-based DER interconnected in reverse-flow parallel form; per the 제3조 definition chain (ESS = 양방향 분산형전원), a distribution-connected BESS is within the article's reach once it takes effect. Detailed functional requirements are delegated to the industry standard 'KSGA-025-15-1 태양광발전용 스마트 인버터의 계통 지원 기능 – 제1부: 배전계통 요구사항 및 시험방법' (제25조 ③). Modal fidelity: the function list says '보유하여야 한다' (shall possess), but 부칙(2023.11.28) ② suspends the whole article's application until a separate effective date is publicly announced, and no later addendum in the 20th-revision text (through 부칙 2025.12.02) lifts that suspension — status verified in the 20th-revision text itself. | 제25조(기능 요구사항) ②항 및 <표 3.3> 분산형전원 계통지원기능, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) + 부칙(2023.11.28) ②항, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) |
The clauses this row cites제25조(기능 요구사항) ②항 및 <표 3.3> 분산형전원 계통지원기능, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) — “ ② 계통지원 기능을 수행하는 분산형전원은 <표3.3>의 기능을 보유하여야 한다. … 주파수-유효전력 제어 기능 (Frequency/Watt): 주파수 변동에 따라 유효전력을 제어 … 출력 램프율 기능 (N-RAMP): 정상운전 상황에서 출력변화율을 제어 ” Translation: “ (2) A distributed energy resource performing grid-support functions shall possess the functions of <Table 3.3>. … Frequency-active power control function (Frequency/Watt): controls active power according to frequency deviation … Output ramp-rate function (N-RAMP): controls the rate of change of output in normal operating conditions ” (분산형전원 배전계통 연계 기술기준 (H0-배전-기준-0015, 제20차 개정), accessed 2026-08-09) 부칙(2023.11.28) ②항, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) — “ ② 2021.12.31. 개정된 분산형전원 배전계통 연계 기술기준 부칙 ①항에도 불구하고 제3절 제25조는 별도 시행일을 공고할 때까지 적용을 유예합니다. ” Translation: “ (2) Notwithstanding Paragraph (1) of the addendum to the Technical Standard for Interconnection of DER to the Distribution System as revised on 31 Dec 2021, application of Article 25 of Section 3 is deferred until a separate effective date is publicly announced. ” (분산형전원 배전계통 연계 기술기준 (H0-배전-기준-0015, 제20차 개정), accessed 2026-08-09) | ||
| Transmission: frequency and voltage operating bands (generator connection conditions) Continuous operating range | 58.5–61.5 Hz: continuous operation at rated output; 57.5–58.5 Hz: hold rated output for at least 20 s; below 57.0 Hz generator tripping is permitted. Voltage: continuous operation at rated output within ±5% of rated terminal voltage 별표8 [발전접속조건] binds generation customers connecting to KEPCO transmission facilities 'unless otherwise specifically agreed in the transmission-facility use contract'. It is generation-scoped and does not name 전기저장장치 (electricity storage); a transmission-connected BESS is bound via its treatment as a generation customer under the same use-contract framework — the instrument that governs a transmission-connected BESS on the KEPCO side is this 이용규정 (별표7/별표8), while dispatch performance sits in KPX's 전력시장운영규칙 (separate instrument, not extracted here). The same 58.5–61.5 Hz / 57.5–58.5 Hz ≥20 s band is repeated for renewables in 별표6 4.나.7). Voltage basis: generator rated terminal voltage; the generator need not run outside ±5% to meet its reactive obligation. | 별표8 [발전접속조건] 3. 기술적 요구 사항, 다. 주파수 변동 1)–2), 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 103) + 별표8 [발전접속조건] 3. 기술적 요구 사항, 나. 전압변동 1), 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 103) |
The clauses this row cites별표8 [발전접속조건] 3. 기술적 요구 사항, 다. 주파수 변동 1)–2), 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 103) — “ 다. 주파수 변동 1) 계통주파수 58.5㎐ ~ 61.5㎐ 범위 내에서 정격출력으로 연속 운전 2) 계통주파수 58.5㎐ ~ 57.5㎐ 범위에서 최소한 20초 이상 정격출력 유지 (57.0㎐ 미만에서는 발전기의 차단 허용) ” Translation: “ da. Frequency variation 1) Continuous operation at rated output within the system-frequency range 58.5 Hz to 61.5 Hz 2) Maintain rated output for at least 20 seconds in the system-frequency range 58.5 Hz to 57.5 Hz (below 57.0 Hz, tripping of the generator is permitted) ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) 별표8 [발전접속조건] 3. 기술적 요구 사항, 나. 전압변동 1), 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 103) — “ 1) 발전기는 정격 단자전압의 ±5% 범위 내에서 정격출력으로 연속 운전능력을 갖추어야 함(발전기는 발전기 무효전력 용량을 충족시키기 위하여 이 전압범위를 벗어나서 연속적으로 운전될 필요는 없음) ” Translation: “ 1) The generator shall have the capability of continuous operation at rated output within ±5% of rated terminal voltage (the generator is not required to operate continuously outside this voltage range in order to meet the generator reactive-power capability) ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) | ||
| Distribution DER: no-trip window 57.5–61.5 Hz and 90–110% voltage (protection settings) Continuous operating range | Frequency trip settings (capacity-independent): f > 61.5 Hz → cease energizing within 0.16 s; f < 57.5 Hz → within 300 s; f < 57.0 Hz → within 0.16 s — leaving 57.5–61.5 Hz with no mandated trip and a 300-s tolerance band 57.0–57.5 Hz. Voltage trip settings (% of nominal): V < 50 → 0.5 s; 50 ≤ V < 70 → 2.00 s; 70 ≤ V < 90 → 2.00 s; 110 < V < 120 → 1.00 s; V ≥ 120 → 0.16 s — leaving 90–110% with no mandated trip These are the abnormal-frequency/voltage separation (clearing-time) settings of 제13조, which delimit the DER's normal operating window at the connection point; they are distinct from the 제24조 ride-through duty tables 표 3.1/표 3.2 (not reproduced in this entry), and 제24조 ② makes the ride-through duty take precedence over these separation times for DER required to ride through. Settings and clearing times must be field-adjustable where necessary, with under-frequency relay settings coordinated with KEPCO system operations. Binds a distribution-connected BESS explicitly via the 제3조 ESS definition (양방향 분산형전원). The ride-through envelope chart on this page is cited from the 14th revision (2021-06-01) of this standard; per 부칙(2025.12.02.) the 20th revision changed the 표 3.1 voltage ride-through durations with effect from 1 Mar 2026, while the 표 2.4/표 2.5 separation tables quoted here carry no such transition note. | 제13조(한전계통 이상시 분산형전원 분리 및 재병입) ④항 및 <표 2.5> 비정상 주파수에 대한 분산형전원 분리시간, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) + 제13조 ③항 제2호 및 <표 2.4> 비정상 전압에 대한 분산형전원 분리시간, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) |
The clauses this row cites제13조(한전계통 이상시 분산형전원 분리 및 재병입) ④항 및 <표 2.5> 비정상 주파수에 대한 분산형전원 분리시간, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) — “ <표 2.5> 비정상 주파수에 대한 분산형전원 분리시간 — 분산형전원 용량: 용량무관 | 주파수 범위 [Hz]: f > 61.5 / f < 57.5 / f < 57.0 | 분리시간 [초]: 0.16 / 300 / 0.16 — 주) 분리시간이란 비정상 상태의 시작부터 분산형전원의 계통가압 중지까지의 시간을 말하며, 필요할 경우 주파수 범위 정정치와 분리시간을 현장에서 조정할 수 있어야 한다. 저주파수 계전기 정정치 조정시에는 한전계통 운영과의 협조를 고려하여야 한다. ” Translation: “ <Table 2.5> DER separation times for abnormal frequency — DER capacity: capacity-independent | Frequency range [Hz]: f > 61.5 / f < 57.5 / f < 57.0 | Separation time [s]: 0.16 / 300 / 0.16 — Note) Separation time means the time from the start of the abnormal condition until the DER ceases to energize the system; where necessary, the frequency-range settings and separation times shall be adjustable in the field. When adjusting under-frequency relay settings, coordination with KEPCO system operations shall be considered. ” (분산형전원 배전계통 연계 기술기준 (H0-배전-기준-0015, 제20차 개정), accessed 2026-08-09) 제13조 ③항 제2호 및 <표 2.4> 비정상 전압에 대한 분산형전원 분리시간, 분산형전원 배전계통 연계 기술기준 H0-배전-기준-0015, 제20차 개정 (2025.12.02) — “ <표 2.4> 비정상 전압에 대한 분산형전원 분리시간 — 전압 범위 (기준전압에 대한 백분율[%]) | 분리시간 [초]: V < 50 → 0.5 / 50 ≤ V < 70 → 2.00 / 70 ≤ V < 90 → 2.00 / 110 < V < 120 → 1.00 / V ≥ 120 → 0.16 — 주 1) 기준전압은 계통의 공칭전압을 말한다. ” Translation: “ <Table 2.4> DER separation times for abnormal voltage — Voltage range (percentage of reference voltage [%]) | Separation time [s]: V < 50 → 0.5 / 50 ≤ V < 70 → 2.00 / 70 ≤ V < 90 → 2.00 / 110 < V < 120 → 1.00 / V ≥ 120 → 0.16 — Note 1) The reference voltage means the nominal voltage of the system. ” (분산형전원 배전계통 연계 기술기준 (H0-배전-기준-0015, 제20차 개정), accessed 2026-08-09) | ||
| Transmission renewables: ramp-limit capability 10% of rated per minute; fast curtailment to 20% in 5 s Ramp rate | Wind and PV inverters must have control capability to limit active-power ramp rate to within 10% of rated per minute upon system-operator instruction. On operator instruction, active output must be reducible to 20% of rated output within 5 seconds (fuel cells excluded) Both are capability requirements exercised on 계통운영자 (system operator) instruction under the emergency dispatch procedure of 전력시장운영규칙 (별표12, 7.1.1) — not standing caps on normal operation; costs of the resulting curtailed energy are not compensated ('이로 인해 발생한 유효전력제어량의 비용은 지급하지 아니 함'). The ramp clause names 풍력 및 태양광 발전기 인버터 only, the fast-curtailment clause applies to 신재생발전기 excluding fuel cells; 전기저장장치 is not named, so neither binds a standalone transmission-connected BESS directly (generation/renewable-scoped). No separate charge-direction ramp limit exists anywhere in the instrument (storage charging is not addressed). | 별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 6)라) 유효전력 증감율 조정, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 87) + 별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 6)가) 급 출력감소 조정 (연료전지 제외), 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 86) |
The clauses this row cites별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 6)라) 유효전력 증감율 조정, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 87) — “ 라) 유효전력 증감율 조정 풍력 및 태양광 발전기 인버터는 계통운영자의 지시에 따라 유효전력 출력 증감율 속도를 정격의 10% 이내/분까지 제한하는 것이 가능한 제어성능을 구비해야 함 ” Translation: “ ra) Active-power ramp-rate adjustment: Wind and photovoltaic generator inverters shall be equipped with control performance capable of limiting the active-power output ramp rate to within 10% of rated per minute, according to the system operator's instruction ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) 별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 6)가) 급 출력감소 조정 (연료전지 제외), 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 86) — “ 가) 급 출력감소 조정 (연료전지 제외) 유효전력의 출력은 계통운영자의 지시 후 5초 이내에 정격 출력의 20%까지로 출력감소 할 수 있어야 함 ” Translation: “ ga) Rapid output-reduction adjustment (fuel cells excluded): active-power output shall be reducible to 20% of rated output within 5 seconds after the system operator's instruction ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) | ||
| Transmission renewables: reactive current within 3 cycles per capability curve; active power restored within 5 s Fault-current injection | Wind/PV/fuel-cell generators must supply fault reactive current within 3 cycles of fault occurrence per the capability curve: 0% Iq/In required at 0.9 pu connection-point voltage, rising linearly to 100% Iq/In at 0.5 pu, with 100% Iq/In below 0.5 pu (figure axis values); pre-fault active power output must be restored within 5 s after connection-point voltage recovers to the continuous-operation range Binds 풍력, 태양광 및 연료전지 발전기 (wind, PV, fuel-cell) newly connecting to the transmission system (22.9 kV dedicated, 70 kV–765 kV) under 별표6 4.나.3); 전기저장장치 is not named, so a standalone transmission-connected BESS is not directly captured (renewable-scoped); no equivalent dynamic reactive-current requirement exists in the generation-generic 별표8. Reactive-vs-active priority and negative-sequence treatment are not stated. No k-factor gain is printed; the curve implies proportional injection between 0.9 and 0.5 pu (slope ≈ 2.5 pu current per pu voltage deviation — interpretation from figure geometry, not source text). | 별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 3)나) 고장 중 무효전류 공급 and figure <고장발생 후 무효전류 공급능력>, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed pp. 84–85) + 별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 3)다) 고장 후 유효전력 회복, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 85) |
The clauses this row cites별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 3)나) 고장 중 무효전류 공급 and figure <고장발생 후 무효전류 공급능력>, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed pp. 84–85) — “ 나) 고장 중 무효전류 공급 풍력, 태양광 및 연료전지 발전기는 계통 전압 지원을 위해서 고장 발생 후 3 Cycle 이내에 아래 그림을 만족하는 무효전류 공급능력을 갖추어야 함 ” Translation: “ na) Reactive-current supply during faults: Wind, photovoltaic and fuel-cell generators shall, for system voltage support, have the capability to supply reactive current satisfying the figure below within 3 cycles after fault occurrence ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) 별표6 [신재생발전기 계통연계기준] 4. 송전용전기설비 접속기준, 나. 기술적 요구사항 3)다) 고장 후 유효전력 회복, 송·배전용전기설비 이용규정 (2025. 7. 1. 전문, printed p. 85) — “ 다) 고장 후 유효전력 회복 풍력, 태양광 및 연료전지 발전기는 고장제거 이후 연계점 전압이 연속운전 전압유지 범위로 복구된 후 5초 이내에 고장 전 유효전력 출력을 할 수 있어야 함 ” Translation: “ da) Active-power recovery after faults: Wind, photovoltaic and fuel-cell generators shall be able to produce the pre-fault active-power output within 5 seconds after the connection-point voltage has recovered to the continuous-operation voltage-maintenance range following fault clearance ” (송·배전용전기설비 이용규정 (2025. 7. 1. 시행 전문), accessed 2026-08-09) | ||
Who does South Korea (KEPCO) bind, and since when?
DER at the distribution PCC, connection classes from LV to 22.9 kV. No date of effect is published here — grid codes are reissued, so check the current issue before relying on it.
These figures are a reading aid, not legal advice. Grid codes are reissued: verify against the current edition before you design to them.
Curve data last checked against the code on — 66 standards, 130 envelopes, published by bess.engineer under CC BY 4.0.
Questions this page answers about South Korea (KEPCO)
- Does South Korea (KEPCO) require ride-through, or only that the plant does not trip?
- Ride-through, for the envelopes on this page — that is what each of them is. It is not everything South Korea (KEPCO) contains: the clauses quoted under the charts also address when the plant may or must trip. The requirement sentence under each chart says which side of the curve is the compliant one.
- Are the numbers on this page taken from South Korea (KEPCO) itself?
- Every breakpoint is read from the code, and where a point was taken off a published figure rather than stated in the clause, the section under that chart says so — on this page that includes an envelope the source only partly defines. The clause each curve came from is quoted under it.
- Which events are charted for South Korea (KEPCO)?
- South Korea (KEPCO) is charted here with 3 envelopes — low-voltage ride-through, high-voltage ride-through, frequency ride-through (LVRT, HVRT, FRT).
Ride-through, in context.
An envelope is a compliance boundary; understanding why it exists is a different question. The ride-through and grid-forming entries cover the engineering, and the Engineering Foundations course builds it from the physics up.
Elsewhere in Asia-Pacific: Singapore (EMA Transmission Code App. F6), Sri Lanka (CEB), Taiwan (TPC), Vietnam BESS (Circular 05/2025/TT-BCT Art. 44), Australia (NER / AEMO), China (GB/T 36547-2024), and 9 more