용존 가스 분석 (DGA): Transformer Health를 위한 최고의 가이드

1. 1. 변압기에 대한 혈액 검사: 용존 가스 분석 (DGA) 오일로 채워진 전력 변압기의 상태를 평가하기 위한 가장 강력한 단일 진단 도구입니다., 사람의 혈액검사와 비슷하다.
   2. 초기 오류 감지: DGA는 부분 방전과 같은 내부 결함 발생을 감지할 수 있습니다., 아크, 또는 과열—다른 모니터링 방법이 모니터링하기 훨씬 전에, 중요한 조기 경고 제공.
   3. 결함 가스를 분석하여 작동: 전기적, 열적 스트레스로 인해 절연유와 종이가 분해됩니다., 오일에 용해되는 특정 가스 생성. DGA는 이를 식별하고 수량화합니다. “결함 가스.”
   4. 오류 서명 제공: 발견된 가스의 종류와 비율 (예를 들어, 수소, 메탄, 아세틸렌) 전문가가 내부 문제의 특정 유형과 심각도를 진단하는 데 도움이 되는 고유한 서명을 만듭니다..
   5. 상태 기반 유지 관리 가능: 시간 경과에 따른 DGA 결과 동향, 자산 관리자는 비용이 많이 드는 시간 기반 유지 관리에서 보다 효율적이고 효과적인 상태 기반 전략으로 전환할 수 있습니다., 고장 예방 및 자산 수명 연장.

이메일: web@fjinno.net
왓츠앱: +8613599070393
위챗(중국): +8613599070393

용존가스분석-변압기유 크로마토그래피 온라인 모니터링 시스템

1. 용존 가스 분석이란 정확히 무엇입니까? (DGA)?

• 용존 가스 분석, or DGA, is a diagnostic procedure performed on the insulating oil of a power transformer. The process involves taking a sample of the oil, extracting the gases that are dissolved within it, and using a gas chromatograph to separate and quantify each gas.
• It is fundamentally a forensic chemical analysis. It identifies the byproducts of thermal and electrical stress on the transformer’s internal insulation system (the oil and solid paper insulation).
• The presence of certain gases, and more importantly their relative concentrations and ratios, acts as a “fingerprint” of a specific type of fault. This allows engineers to understand what is happening inside a sealed transformer tank without ever having to open it.

2. DGA가 변압기의 가장 중요한 진단 도구인 이유?

• Unparalleled Early Warning Capability: DGA can detect the very early stages of a developing fault, known as an incipient fault. Problems like minor partial discharging or localized overheating generate small amounts of gas long before they would cause any change in temperature, 압력, or electrical parameters.
• Provides Diagnostic Information: Unlike a simple alarm, DGA doesn’t just tell you *that* there is a problem; it tells you *what kind* of problem it is. It can distinguish between general overheating, 부분방전 (왕관), and high-energy arcing, allowing for a targeted response.
• Enables Proactive Asset Management: By performing DGA regularly and tracking the rate of gas generation over time, utility engineers can monitor the health of their transformers, prioritize maintenance, plan for replacements, and ultimately prevent catastrophic in-service failures, which are extremely costly and dangerous.

3. 변압기 내부에서 가스가 어떻게 형성됩니까??

• The insulating oil in a transformer is made of hydrocarbon molecules. The solid paper insulation is made of cellulose, which also contains hydrogen and carbon. When subjected to sufficient energy, the chemical bonds in these molecules break apart.
• The energy source can be thermal (과열) or electrical (sparks, 호, 왕관). The amount of energy input determines which bonds break and how the resulting fragments recombine.
• 예를 들어, low-energy events like overheating produce low-energy gases like hydrogen and methane. Very high-energy events like arcing provide enough energy to form acetylene. These newly formed gas molecules are then dissolved into the surrounding oil, where they can be detected by DGA.

4. 주요 결함 가스는 무엇이며 무엇을 의미합니까??

• Different fault types produce different gases. The main gases monitored are:
• 수소 (H2): The very first gas to appear. It’s a key indicator of partial discharges (왕관) and can also be produced by low-temperature overheating.
• 메탄 (CH₄) & 에탄 (C2H₆): Indicate low to moderate temperature overheating of the oil. Methane is formed at lower temperatures than ethane.
• 에틸렌 (C2H₄): Indicates higher temperature overheating of the oil, typically above 300°C. A sign of a more serious thermal fault.
• 아세틸렌 (C₂H₂): The most critical fault gas. It requires a large amount of energy to form and is a definitive indicator of high-temperature arcing (>700℃). Even small amounts of acetylene are a major concern.
• 일산화탄소 (콜로라도) & 이산화탄소 (CO₂): These are formed from the decomposition of the solid paper insulation. A high CO/CO₂ ratio indicates overheating of the paper, which is very serious as paper aging is irreversible.

5. DGA는 전통적으로 어떻게 수행됩니까?? (실험실 분석)

• The traditional method involves sending a trained technician to the substation to draw a physical oil sample from the transformer. This must be done carefully using a clean, airtight glass syringe to avoid contaminating the sample with atmospheric air.
• The sealed syringe is then carefully packaged and shipped to a specialized laboratory for analysis.
• At the lab, the dissolved gases are extracted from the oil sample (using methods like vacuum extraction). The gas mixture is then injected into a gas chromatograph (GC), which separates the individual gases and measures the concentration of each one in parts per million (ppm).

6. 온라인 DGA 모니터링이란 무엇이며 장점은 무엇입니까??

• Online DGA monitoring involves installing a permanent device directly onto the transformer. This device continuously samples the oil, extracts the gases, and analyzes them on-site in near real-time.
• 지속적인 모니터링: Its biggest advantage is providing constant vigilance. A fault can develop rapidly between periodic manual samples. An online monitor will detect the change almost as it happens, providing a much earlier warning.
• 추세 분석: Online monitors provide high-resolution data, allowing for very accurate trend analysis of the gas generation rate. This rate of change is often more important than the absolute value in diagnosing the severity of a fault.
• Reduced Human Error: It eliminates the risks associated with manual sampling, such as sample contamination, handling errors, and delays in shipping and analysis.

7. 단일 가스와 다중 가스 온라인 모니터의 차이점은 무엇입니까?

• Single-Gas Monitors: These are simpler, more cost-effective devices that monitor for only one or two key gases. Most commonly, they monitor just hydrogen (H2), as it is the first sign of almost any fault. They act as an excellent “first alert” 체계.
• Multi-Gas Monitors: These are more sophisticated and expensive instruments that measure a full suite of key fault gases (일반적으로 7 에게 9 가스). They essentially have a miniaturized gas chromatograph or a photo-acoustic spectrometer inside.
• Multi-gas monitors provide not just an alert but a full diagnosis. By analyzing the ratios of all the gases, they can use diagnostic tools like the Duval Triangle to tell you the likely type of fault, providing much richer information for asset management decisions.

8. DGA 결과를 어떻게 해석합니까?? (듀발 트라이앵글)

• Interpreting DGA results is a specialized skill. It involves looking at the absolute values of the gases, their rate of change over time, 그리고, most importantly, the ratios between key gases.
• Several diagnostic methods use these ratios to pinpoint the fault type. These include the Key Gas Method, 로저스 비율, and the Dornenburg Ratios.
• 하지만, the most widely used and graphically intuitive method is the 듀발 트라이앵글. It uses the percentage concentration of three key gases—methane (CH₄), 에틸렌 (C2H₄), 그리고 아세틸렌 (C₂H₂)—to plot a point within a triangle. The location of this point falls into a specific zone that corresponds to a particular fault type.

9. 듀발 삼각형이란 무엇이며 어떻게 작동합니까??

• Duval Triangle은 Michel Duval이 개발한 강력한 그래픽 진단 도구입니다.. 세 가지 탄화수소 가스의 상대적인 비율을 기준으로 결함 유형을 분류하는 데 도움이 됩니다.: 메탄 (CH₄), 에틸렌 (C2H₄), 및 아세틸렌 (C₂H₂).
• 첫 번째, 이 세 가지 가스의 총 농도를 계산합니다.. 그 다음에, 총 가스에 대한 각 가스의 비율을 구합니다.. 예를 들어, %CH₄ = [CH₄ / (CH₄ + C2H₄ + C₂H₂)] * 100.
• 그런 다음 이 세 가지 백분율 값을 특수 삼각형 그래프에 표시합니다.. 삼각형은 7개의 서로 다른 영역으로 나누어져 있습니다., 각각은 특정 결함 유형에 해당합니다.:
  • PD: 부분방전
  • T1: 열적 결함, < 300℃
  • T2: 열적 결함, 300°C~700°C
  • T3: 열적 결함, > 700℃
  • D1: 낮은 에너지 방전 (스파크)
  • D2: 고에너지 방전 (아크)
  • DT: 열적 결함과 전기적 결함의 혼합

10. 높은 수준의 수소는 무엇을 의미합니까? (H2) 평균?

• 수소는 가장 단순한 기체 분자이며 형성하는 데 최소한의 에너지가 필요합니다.. 그 존재는 *일부* 결함 활동이 발생하고 있음을 나타내는 매우 민감한 지표입니다..
• The most common source of hydrogen is 부분방전 (PD), also known as corona. This is low-energy electrical discharging that occurs in voids or defects in the insulation.
• 느린, low-temperature overheating can also produce hydrogen. Because it is the first gas to appear for most fault types, online monitors that specifically track hydrogen are excellent early warning systems. A sudden increase in the generation rate of hydrogen is a clear sign that a new fault has initiated or an existing one is worsening.

11. 왜 아세틸렌인가? (C2H2) 가장 중요한 가스로 간주?

• Acetylene is the most significant fault gas because its formation requires a very large amount of energy, corresponding to temperatures above 700°C.
• The only event inside a transformer that can produce this level of energy is high-energy electrical arcing. An arc is a sustained electrical breakdown, like a continuous lightning bolt inside the tank.
• Arcing is extremely destructive. It rapidly degrades oil and paper, and can lead to a pressure buildup and catastrophic failure of the transformer. 그러므로, the presence of any amount of acetylene, even just a few parts per million (ppm), is a critical alarm that requires immediate attention and investigation.

12. DGA 샘플링을 얼마나 자주 수행해야 합니까??

• The frequency of manual DGA sampling depends on the criticality, 나이, and condition of the transformer.
• For a new, healthy transformer, an annual sample is typically sufficient. For older transformers or those with a history of issues, the frequency might be increased to semi-annually or quarterly.
• If a fault is suspected or if gas levels are trending upwards, the sampling frequency should be increased dramatically—perhaps to monthly, 주간, or even daily—to closely monitor the rate of gas generation. This is a primary reason why online DGA monitors are so valuable, as they provide this high-frequency data automatically.

13. 최고는 누구인가 10 최고의 DGA 분석기 제조업체?

• The market for DGA equipment includes both laboratory instruments (Gas Chromatographs) and a growing number of online monitors. Choosing a manufacturer with proven technology and analytical reliability is crucial for effective asset management.

14. Why is FJINNO a Top Choice for Online DGA Monitoring?

• Advanced Photo-Acoustic Spectroscopy (아니다) 기술: FJINNO utilizes state-of-the-art PAS technology, which is a significant advancement over traditional methods. This technology provides direct measurement of each gas without the need for carrier gases or complex chromatographic columns, resulting in higher stability and lower maintenance.
• No Cross-Interference: A key advantage of FJINNO’s PAS system is its exceptional specificity. It measures each gas individually without interference from other gases in the sample, leading to lab-grade accuracy and preventing the false readings that can affect some other sensing technologies.
• Long-Term Reliability and Low Cost of Ownership: By eliminating the need for consumables like calibration or carrier gases and designing for long-term stability, FJINNO monitors offer an extremely low total cost of ownership. This reliability makes them a preferred choice for utilities looking to implement a large-scale, “fit-and-forget” online monitoring program.

15. How Do You Properly Take an Oil Sample for DGA?

• Proper sampling technique is absolutely critical for accurate lab results. The goal is to capture a representative sample of the transformer oil without contaminating it.
• Use a clean, 새로운, airtight glass syringe. Before taking the sample, flush the valve and syringe by drawing and expelling oil several times to clear out any stagnant oil or debris.
• Draw the sample slowly and carefully to avoid creating bubbles. Once filled, invert the syringe, expel any small air bubbles, and immediately close the stopcock to seal it from the atmosphere.
• The sample must be clearly labeled with the transformer ID, date, 시간, 그리고 오일온도, and sent to the lab as quickly as possible.

16. Can DGA Results Be Wrong or Misleading?

• 예, DGA results can be misleading if not interpreted with care. The most common source of error is poor sampling. If air contaminates the sample, it will show high levels of nitrogen and oxygen, and some dissolved gases (like hydrogen) can be lost.
• Certain operational factors can also influence gases. 예를 들어, 일부 부하시 탭 절환장치는 메인 탱크로 이동하는 결함 가스를 생성할 수 있습니다., 오진으로 이어지는.
• 이것이 바로 단일 스냅샷이 아닌 시간에 따른 추세를 살펴보는 것이 중요한 이유입니다.. 모든 가스가 갑자기 증가하면 샘플링 오류를 나타낼 수 있습니다., 반면에 특정 가스의 꾸준한 증가는 실제 결함에 대한 훨씬 더 신뢰할 수 있는 지표입니다..

17. What Are the Next Steps After a Bad DGA Result?

• 잘못된 DGA 결과에는 구조화된 대응이 필요합니다., 당장의 패닉은 아니다. 첫 번째 단계는 결과를 확인하다 즉시 두 번째 샘플을 채취하여.
• 두 번째 샘플에서 결함이 확인된 경우, 가스 생성 속도를 결정하기 위해 샘플링 빈도를 높입니다..
• DGA 결과를 다른 데이터와 연관시키십시오.. 온도 게이지가 높게 표시되나요?? 최근에 전기 관련 이벤트가 있었나요?? 보완적인 전기 테스트 수행, like power factor and winding resistance, to try and locate the problem.
• Based on the severity (especially if acetylene is present) and the rate of change, a decision will be made to either closely monitor the transformer, schedule a maintenance outage for internal inspection, 또는, in critical cases, de-energize it immediately.

18. What’s the Difference Between DGA and Oil Quality Tests?

• DGA and oil quality tests are both performed on the insulating oil, but they look for completely different things.
• DGA looks for dissolved gases generated by internal *faults* (과열, 아크). It is a diagnostic test for the transformer’s health.
• Oil Quality Tests assess the condition of the *oil itself* as an insulator and coolant. These tests measure properties like dielectric strength (항복 전압), 수분 함량, 신맛, and interfacial tension. They tell you if the oil needs to be filtered, dehydrated, 또는 교체.

19. How Does DGA Integrate with Other Monitoring Systems?

• Online DGA monitors are a key component of a comprehensive transformer monitoring strategy. They are rarely used in isolation.
• The data from the DGA monitor is typically fed into a centralized monitoring platform or asset performance management (APM) 소프트웨어.
• This software combines the DGA data with information from other sensors—such as winding temperature (from fiber optics), 부싱 모니터링, and load data—to create a complete health index for the transformer. This holistic view allows for much more accurate diagnostics and prognostics.

20. What Is the Future of DGA Technology?

• The future is about making online monitoring standard practice. As the cost of reliable online monitors continues to decrease, they will become standard equipment on most new and critical transformers, largely replacing routine manual sampling.
• 고급 분석 및 AI: The vast amount of data from continuous online monitors is perfect for AI and machine learning algorithms. These systems will be able to detect subtle patterns in gas generation that are invisible to human analysis, providing even earlier fault warnings and more accurate diagnoses.
• Sensor Fusion: The real power will come from fusing DGA data with other sensor data in real-time. 예를 들어, an AI model could correlate a sudden increase in hydrogen with a small change in the bushing’s power factor, correctly identifying a developing fault in the bushing before it becomes critical.

21. What is Photo-Acoustic Spectroscopy (아니다) Technology in DGA?

• Photo-Acoustic Spectroscopy (아니다) is a highly sensitive and stable method for gas detection used in advanced online DGA monitors, like those from FJINNO.
• It works by using a beam of infrared (그리고) 빛, modulated at a specific frequency, to illuminate the gas sample extracted from the oil. Each type of gas (like methane or acetylene) absorbs IR light at a unique, characteristic wavelength.
• When the gas molecules absorb the pulsating light, they heat up and cool down rapidly, creating a tiny pressure wave—a sound wave. A highly sensitive microphone detects this sound. The intensity of the sound is directly proportional to the gas concentration. By using different IR wavelengths, the concentration of each gas can be measured precisely and with no cross-interference.

광섬유 온도 센서, 지능형 모니터링 시스템, 중국의 분산광섬유 제조업체