- Core monitoring functions of transformer comprehensive online monitoring systems, including oil dissolved gas analysis (DGA), pelepasan sebagian (PD) deteksi, and temperature sensing
- Synergistic application of multi-parameter monitoring to enhance fault diagnosis accuracy for oil-immersed transformer online surveillance
- Technical principles, implementation methods, and performance indicators of integrated transformer online monitoring solutions
- Practical application cases and best practices for transformer all-in-one online monitoring platforms
2. Analisis Gas Terlarut Minyak (DGA) for Transformer Comprehensive Online Monitoring Systems
2.1 Basic Principles of DGA in Transformer Online Surveillance
Oil dissolved gas analysis (DGA) is a cornerstone function of oil-immersed transformer online DGA monitors. It leverages the characteristic that insulating oil and solid insulation materials decompose into specific gases under thermal or electrical stress. When internal faults (misalnya, terlalu panas, pelepasan sebagian) occur in transformers, gases such as hydrogen (H₂), metana (CH₄), etilen (C₂H₄), asetilen (C₂H₂), karbon monoksida (BERSAMA), dan karbon dioksida (CO₂) are released and dissolved in the oil. By analyzing the composition and concentration of these dissolved gases, transformer DGA online monitoring devices can identify fault types and severity at an early stage.
Different fault modes produce distinct gas profiles: local discharge primarily generates H₂ and CH₄; low-temperature overheating (<300℃) emits CH₄ and ethane (C₂H₆); mid-temperature overheating (300-700℃) focuses on C₂H₄; high-temperature overheating (>700℃) produces C₂H₄ and trace C₂H₂; and arcing discharge releases large amounts of C₂H₂ and H₂. Selain itu, kelembaban (H₂O) content is a critical supplementary indicator, as excess moisture degrades insulation performance and accelerates aging.
2.2 Implementation Methods of Transformer DGA Online Monitoring Devices
Modern integrated transformer DGA monitoring systems primarily use two technical routes: kromatografi gas (GC) and infrared spectroscopy (DAN). Advanced systems adopt carrier-gas-free DGA technology, enabling real-time monitoring of key gas concentrations with sampling intervals as short as minutes—far faster than traditional offline testing (3-6 siklus bulan).
The implementation process includes four key steps:
- Gas Sampling & Separation: Specialized sampling modules extract dissolved gases from transformer oil. Gas chromatography columns separate mixed gases into individual components for sequential detection.
- Deteksi Gas: Separated gases are quantified via detectors like thermal conductivity detectors (TCD) untuk H₂ dan oksigen (HAI₂), dan detektor ionisasi api (FID) untuk gas hidrokarbon (CH₄, C₂H₄, C₂H₆, C₂H₂).
- Analisis Data & Pengolahan: Sinyal detektor diubah menjadi data digital, dianalisis melalui algoritma untuk menghitung konsentrasi gas, dan dibandingkan dengan ambang batas standar untuk menilai status transformator.
- Tampilan Hasil & Menggelisahkan: Data yang diproses divisualisasikan pada antarmuka pemantauan. alarm DGA online transformator memicu peringatan multi-level (peringatan, kritis) ketika konsentrasi gas melebihi batas yang ditentukan, mendorong tim pemeliharaan untuk bertindak.
Mutakhir monitor DGA berbasis laser untuk transformator gunakan laser merdu untuk memindai puncak penyerapan gas tertentu. Berdasarkan Hukum Beer-Lambert (intensitas penyerapan sebanding dengan konsentrasi), mereka mencapai deteksi selektivitas tinggi, secara signifikan meningkatkan sensitivitas dan akurasi. Beberapa sistem canggih juga mengintegrasikan kelembapan oli, kerugian dielektrik, and particle count monitoring to comprehensively evaluate insulation oil condition.
2.3 Performance Indicators of Transformer DGA Online Sensors
The accuracy of transformer DGA online monitoring equipment directly impacts fault diagnosis reliability. Key technical indicators for modern systems include:
- Rentang Deteksi & Kepekaan: Typical concentration range is 0-1000 μL/L (ppm). For critical gases like C₂H₂, sensitivity reaches 0.1 μL/L or lower, enabling early detection of latent faults.
- Akurasi Pengukuran: Generally controlled within ±5% for most gases; relative deviation up to ±20% for low-concentration gases (misalnya, <5 μL/L C₂H₂).
- Repeatability: Variation in repeated measurements of the same oil sample is <3%, ensuring data consistency.
- Analysis Cycle: Ranges from minutes to hours, far faster than offline methods (hours to days).
- Suhu & Pressure Compensation: Automatic calibration for gas solubility changes due to transformer operating temperature and pressure, ensuring accuracy under varying conditions.
These high-precision indicators allow oil-immersed transformer DGA online systems to capture minute internal changes—for example, detecting gas variations caused by a 20-30℃ temperature rise, which is unachievable with traditional offline testing.
3. Pelepasan Sebagian (PD) Detection for Integrated Transformer Online Monitoring Solutions
3.1 Principles of Transformer PD Online Monitoring Modules
Debit sebagian (PD) refers to localized breakdown in transformer insulation systems where the electric field exceeds the dielectric strength, without forming a贯穿性 (through-going) saluran. While PD does not immediately cause insulation failure, long-term exposure erodes materials, akhirnya menyebabkan kerusakan total. Modul deteksi online pelepasan sebagian transformator mendeteksi PD dengan memantau fenomena fisik yang dihasilkan selama pelepasan:
- Sinyal Pulsa Listrik: PD menghasilkan pulsa arus frekuensi tinggi (rentang kHz hingga MHz) dapat dideteksi melalui transformator arus frekuensi tinggi (HFCT) dipasang pada kabel ground trafo atau bushing tap.
- Sinyal Gelombang Elektromagnetik: PD memancarkan radiasi elektromagnetik (puluhan hingga ratusan MHz). Frekuensi sangat tinggi (UHF) Sensor PD untuk transformator menangkap sinyal-sinyal ini untuk deteksi dan lokalisasi.
- Sinyal Ultrasonik: Getaran mekanis yang diinduksi PD menghasilkan gelombang akustik (kHz ke MHz), terdeteksi oleh sensor ultrasonik yang dipasang pada dinding tangki trafo.
- Sinyal Optik: PD berenergi tinggi memancarkan cahaya lemah, dapat dideteksi melalui sensor PD serat optik untuk transformator—ideal untuk interferensi elektromagnetik tinggi (EMI) lingkungan.
- Perubahan Kimia: PD menguraikan bahan insulasi menjadi gas (misalnya, H₂, CH₄), which aligns with DGA data for cross-validation.
The primary goal of transformer PD online monitoring systems is early detection of insulation defects, assessment of insulation condition, and prediction of insulation life—addressing gaps in DGA, which may miss non-pulsed PD stages that do not generate gas.
3.2 Technical Routes for Transformer PD Online Monitoring Equipment
Common implementation methods for integrated transformer PD online surveillance termasuk:
3.2.1 Pulse Current Method (IEC 60270 Sesuai)
This is the foundational PD detection method. Transformer PD pulse current sensors (misalnya, kumparan Rogowski) installed on bushing taps or core ground wires capture nanosecond-scale pulses. When insulation defects generate micro-discharges, electromagnetic pulses propagate through the circuit, and sensors extract signals via electromagnetic coupling. Sensitivity reaches 50 pc, suitable for detecting weak discharges in cable joints and switchgear.
3.2.2 Frekuensi Ultra Tinggi (UHF) Deteksi
Transformer UHF PD monitoring systems use UHF sensors (300 MHz-3 GHz) to receive electromagnetic waves from PD. Key advantages include strong anti-interference (site interference concentrates in low frequencies) dan sensitivitas tinggi (1-5 pc). UHF technology excels at locating PD sources, critical for identifying internal insulation defects.
3.2.3 ultrasonik (Emisi Akustik, AE) Deteksi
Transformer ultrasonic PD sensors capture mechanical vibrations from PD. Gas ionization during discharge causes local expansion, generating acoustic waves. Time-of-flight or phase analysis localizes discharge points. This method offers strong EMI resistance, ideal for complex electromagnetic environments, though sensitivity is lower (50-100 pc) compared to UHF.
3.2.4 Tegangan Bumi Sementara (TEV) Deteksi
Transformer TEV PD monitors measure high-frequency transient signals radiated from equipment surfaces, enabling non-intrusive online detection. Mudah dipasang, TEV is suitable for switchgear but has limited detection range, making it a supplementary method for transformers.
Modern transformer comprehensive PD online systems adopt multi-technology fusion—e.g., “electrical-acoustic combined detection”—simultaneously capturing current pulses and acoustic signals. Upper-layer software calculates discharge amplitude, frekuensi, dan lokasi, delivering comprehensive PD monitoring. This fusion enhances accuracy and reduces false alarms.
3.3 Localization Capabilities of Transformer PD Online Sensors
PD localization is critical for targeted maintenance. Transformer PD online localization systems achieve varying precision via different methods:
- Single-Point Localization: Time-delay methods using single sensors offer precision of 5-10% of transformer dimensions.
- Multi-Sensor Array Localization: Time-of-Arrival (TOA) or Direction-of-Arrival (DOA) with multi-sensor arrays achieves centimeter-level precision.
- Electrical-Acoustic Combined Localization: Fusing electrical and acoustic signals reduces error to 10-20 cm, ideal for large transformers.
Penggunaan sistem tingkat lanjut electromagnetic time reversal (EM TR) teknologi—capturing PD signals from both winding ends, reversing the time axis to precisely localize sources, achieving millimeter-level precision under ideal conditions. Selain itu, phase-resolved partial discharge (PRPD) analisa Dan phase-resolved pulse sequence (PRPS) analisa automatically identify discharge types (misalnya, floating discharge, void discharge) by comparing with defect pattern libraries, aiding fault root-cause analysis.
4. Temperature Monitoring for Transformer All-in-One Online Monitoring Platforms

4.1 Principles of Transformer Online Temperature Sensing Systems
Temperature is a critical indicator of transformer health—excessive heat accelerates insulation aging and increases failure risk. Transformer online temperature monitoring systems operate on heat balance principles Dan heat transfer laws: during operation, transformer losses (iron, tembaga, stray) convert to heat, dissipated via conduction, konveksi, dan radiasi. When heat generation equals dissipation, temperature stabilizes.
Key temperature parameters monitored by oil-immersed transformer temperature online sensors termasuk:
- Suhu Minyak Atas: Reflects overall heat dissipation and load conditions; the most commonly monitored parameter.
- Suhu Titik Panas Berliku: The highest temperature in windings (typically mid-upper section), the primary factor influencing insulation aging.
- Suhu Inti: Abnormal core temperature indicates faults like core short circuits or multi-point grounding.
- Kenaikan Suhu Minyak: Difference between top oil and ambient temperature, reflecting heat dissipation capacity and load levels.
- Kenaikan Suhu Berliku: Difference between winding and ambient temperature, critical for assessing load capacity.
Per thermodynamics, insulation aging rate follows an exponential relationship with temperature—every 8-10℃ increase doubles aging speed. Dengan demikian, precision transformer temperature online monitors are essential for extending equipment lifespan.
4.2 Technical Routes for Transformer Online Temperature Sensors
4.2.1 Contact Temperature Sensing
- Detektor Suhu Resistensi Platinum (RTD): Based on resistance-temperature characteristics (misalnya, Pt100: 100Ω at 0℃). Transformer Pt100 online sensors menawarkan akurasi yang tinggi (±0,1-0,5℃) dan stabilitas, ideal for long-term monitoring.
- Termokopel: Utilize the Seebeck effect (voltage from temperature differences). Wide temperature range but lower accuracy (±1-2℃), suitable for high-temperature zones.
- Termistor: Semiconductor-based with high sensitivity but poor linearity; limited to specific temperature ranges.
4.2.2 Penginderaan Suhu Serat Optik

- Sensor Serat Optik Fluoresen: Transformer fluorescent fiber temperature monitors use temperature-sensitive fluorescent materials. When excited by specific wavelengths, fluorescence decay time correlates strictly with temperature. Advantages include strong EMI resistance and high accuracy (±0,5℃), perfect for high-voltage environments.
- Kisi Serat Bragg (FBG) Sensor: Transformer FBG temperature sensors rely on refractive index changes in FBGs with temperature. Accuracy reaches ±1℃, enabling distributed monitoring.
- Serat Optik Terdistribusi Sensor: Use optical time-domain reflectometry (OTDR) for continuous temperature mapping along fibers. Resolusi spasial <1M, accuracy ±1-2℃, suitable for large-area monitoring (misalnya, belitan, inti).
4.2.3 Non-Contact Temperature Sensing
Transformer infrared temperature cameras measure surface temperature via infrared radiation. Easy to use but limited to external surfaces (cannot detect internal winding/core temperature) and susceptible to environmental interference (debu, kelembaban).
4.2.4 Indirect Winding Hot-Spot Temperature Calculation
- Current Thermal Effect Method: Calculates winding temperature by combining load current, suhu minyak atas, and winding resistance-temperature characteristics.
- Model-Based Calculation: Uses thermal transfer equations and parameters (suhu minyak atas, memuat arus, suhu sekitar) to estimate hot-spot temperature via transformer thermal models.
Modern integrated transformer temperature online systems combine multiple technologies—e.g., Pt100 for top oil temperature, fluorescent fiber optics for winding hot spots, and infrared for external巡检 (patrols)—creating a multi-layered monitoring network.
4.3 Performance of Transformer Online Temperature Monitoring Equipment
Key performance indicators for transformer temperature online monitoring devices termasuk:
- Kisaran Suhu: -40℃ hingga +150℃, covering normal operation and extreme conditions.
- Ketepatan: ±1℃ for top oil temperature, ±2℃ for winding hot spots (±0.5℃ with fiber optic direct measurement), ensuring reliable insulation aging assessment.
- Waktu Respons: ≤1 minute for rapid detection of abnormal temperature rises.
- Stabilitas Jangka Panjang: Annual drift ≤±0.5℃, guaranteeing data reliability over years.
Digital transformer temperature online sensors include built-in temperature compensation and linearization, outputting digital data directly to reduce EMI-induced errors in analog signal transmission.
5. Synergistic Application of Transformer Comprehensive Online Monitoring Systems
5.1 Synergy Principles of Multi-Parameter Transformer Online Monitoring
The value of transformer comprehensive online monitoring platforms lies in synergistic multi-function integration, combining data from DGA, PD, and temperature monitoring to deliver comprehensive, accurate status assessments. Key synergy principles include:
- Information Complementarity: DGA reflects long-term insulation degradation; PD detects real-time insulation defects; temperature monitors load and heat dissipation. Together, they address blind spots of single-parameter monitoring.
- Time-Scale Synergy: PD responds to short-term changes; DGA reflects long-term trends; temperature bridges both. This temporal coverage captures fault evolution from initiation to development.
- Spatial-Scale Synergy: PD offers high spatial resolution (cm-level localization); temperature maps regional heat distribution; DGA provides global status. This spatial hierarchy pinpoints fault locations and assesses impact ranges.
- Physical Phenomenon Correlation: PD causes gas generation (DGA) and local heating (suhu); overheating accelerates PD and insulation aging. Analyzing these correlations deepens understanding of fault mechanisms.
5.2 Data Fusion for Transformer All-in-One Online Monitoring
Transformer online monitoring data fusion systems integrate multi-source data via advanced methods:
- Threshold-Based Alarm: Multi-level thresholds for each parameter (misalnya, DGA: C₂H₂ >5 μL/L (peringatan), PD: >1000 pc (alarm), suhu: >130℃ (kritis)) trigger coordinated alerts.
- Analisis Tren: Statistical methods, time-series models, and machine learning (misalnya, linear regression, LSTM) identify abnormal trends—e.g., simultaneous H₂ increase (DGA), rising PD amplitude, and 5℃ hot-spot temperature rise indicate developing insulation defects.
- Correlation Analysis: Quantify relationships between parameters (misalnya, PD amplitude vs. H₂ concentration, hot-spot temperature vs. memuat arus) to identify abnormal correlations.
- Pengenalan Pola: Sistem pakar, jaringan saraf, and deep learning match multi-parameter patterns to known fault models—e.g., “high C₂H₂ (DGA) + high PD (UHF) + local hot spot (suhu)” = arcing discharge.
- Multi-Variate Statistical Analysis: Principal Component Analysis (PCA) and Partial Least Squares-Discriminant Analysis (PLS-DA) reduce data dimensionality, extracting key features for efficient diagnosis.
Penggunaan sistem modern edge-cloud hybrid architectures: edge devices process real-time data for instant alerts; cloud platforms store historical data for deep analysis (misalnya, remaining life prediction), balancing speed and depth.
5.3 Application Cases of Synergistic Transformer Online Monitoring
5.3.1 Winding Hot-Spot & PD Co-Monitoring
Kasus: A 220 kV transformer showed abnormal DGA (total hydrocarbons: 200 μL/L, dominant CH₄/C₂H₄), moderate PD (500 pc), and 15℃ higher winding hot-spot temperature. Synergistic analysis diagnosed local winding overheating from poor wire soldering, causing insulation degradation and PD. Tindakan: Prompt repair of soldering joints prevented winding short circuits.
5.3.2 Core Multi-Point Grounding Diagnosis
Kasus: A 110 kV transformer had abnormal core ground current (0.5 A, normal ≤0.1 A), slight DGA (H₂/CH₄ increase), and 10℃ higher core temperature. Synergistic analysis identified core multi-point grounding from metal debris, causing circulating currents, panas berlebih lokal, and oil decomposition. Tindakan: Debris removal restored normal ground current and gas levels.
5.3.3 Cooling System Fault Detection
Kasus: A 500 kV transformer had 15℃ rapid top oil temperature rise, slight DGA (H₂/CH₄ increase), and no PD anomalies. Synergistic analysis pinpointed cooling fan failure, reducing heat dissipation. Tindakan: Fan replacement restored normal temperature and gas levels.
These cases demonstrate that synergistic transformer comprehensive online monitoring improves diagnosis accuracy by 20-30% and reduces false alarms by >50%, critical for reliable transformer operation.
6. Technical Trends & Application Guidelines for Transformer Online Monitoring Systems
6.1 Innovation Trends in Transformer Online Monitoring Technology
- Penggabungan Multi-Sensor: Integrating vibration, kebisingan, oil particle count, and moisture monitoring into transformer multi-parameter online systems for holistic status assessment.
- High-Precision Sensors: Quantum sensors for single-photon PD detection, and nanomaterial-based DGA sensors for ultra-low concentration gas measurement.
- AI & Big Data: Deep learning for fault prediction (misalnya, LSTM for insulation aging), and digital twins for virtual monitoring and maintenance simulation.
- Edge-Cloud Computing: Edge devices for real-time AI inference; cloud platforms for big data analytics and global fleet management.
- Standardisasi: Adopting IEC 61850, Modbus, and OPC UA for interoperability between multi-vendor transformer online monitoring systems.
6.2 Application Guidelines for Transformer Online Monitoring Solutions
To maximize value from transformer comprehensive online monitoring systems, follow these guidelines:
- Implementasi Bertahap: Fase 1: Deploy DGA and temperature monitoring; Fase 2: Add PD detection; Fase 3: Integrate with substation automation systems.
- Differentiated Deployment: Full monitoring for critical assets (misalnya, 500 transformator kV); basic monitoring for non-critical units (misalnya, 110 transformator kV).
- Data-Driven Maintenance: Use monitoring data to shift from scheduled to condition-based maintenance, reducing costs by 30-40%.
- Skill Development: Train personnel on sensor calibration, analisis data, and fault diagnosis to leverage system capabilities.
- Cyber Security: Implement encryption, kontrol akses, and intrusion detection to protect connected transformer online monitoring systems from cyber threats.
By following these guidelines, utilities and industrial users can fully leverage transformer comprehensive online monitoring technology to enhance reliability, extend equipment life, and optimize maintenance costs.
Sensor suhu serat optik, Sistem pemantauan cerdas, Produsen serat optik terdistribusi di Cina
![]() |
![]() |
![]() |
Sensor suhu serat optik INNO ,sistem pemantauan suhu.



