HF-T-602 Transformer DGA Online Monitoring System

Product Overview of Transformer DGA Online Monitoring

As the core of power grids, transformers guarantee system power supply stability. Statistics indicate over half of major transformer faults can be prewarned by online monitoring, and DGA is the globally acknowledged solution to avoid breakdowns of oil-filled electrical equipment.

This DGA online monitoring system is built with next-generation photoacoustic spectroscopy detection technology, serving as a fully domestically developed intelligent sensing device for 110kV and above oil-immersed power equipment.

It continuously monitors 9 types of characteristic gases and moisture content dissolved in transformer oil, accurately capturing early hidden faults including partial discharge, overheating and insulation deterioration inside equipment. It provides operation data for maintenance teams, facilitates the power grid’s transformation from periodic maintenance to condition-based maintenance, drastically cuts unplanned power outages and extends the full service life of transformers.

Core Product Advantages

Consumable-Free & Maintenance-Free Design

Eliminates consumable components such as high-pressure carrier gas cylinders and chromatographic columns required by traditional oil chromatography devices. No carrier gas replacement or regular consumable refilling is needed during operation, eliminating safety hazards caused by high-pressure gas cylinders near transformers. Annual maintenance workload is reduced by over 90% compared with conventional equipment.

High Precision & Anti-Interference Detection

Adopts narrow-linewidth DFB laser and active resonant photoacoustic cell together with intelligent spectrum analysis algorithms to effectively eliminate cross-interference between different gases. The measurement accuracy of acetylene (key indicator) reaches 0.1ppm, fully meeting the demand for trace fault gas capture in extra-high voltage and ultra-high voltage scenarios.

Closed-Loop Operation with Zero Oil Sample Loss

Equipped with a constant-temperature vacuum degassing module. The whole detection process is isolated from ambient air, and 100% of the analyzed oil flows back into the transformer tank, achieving zero contamination and zero loss of oil samples without any negative impact on transformer oil quality.

Fast Response & Multi-Dimensional Sensing

The full-component detection cycle is shortened to 60 minutes, and a dedicated acetylene test delivers results within 30 minutes. It supports multi-point polling detection with a new set of monitoring data refreshed every 10 minutes, boosting fault early warning speed by more than twice versus traditional products.

Full Protocol Compatibility & Remote Management

Natively supports mainstream power communication protocols including IEC 61850, MODBUS and DNP3, enabling seamless connection with grid PMS3.0 systems and local SCADA platforms. The matched remote centralized management software realizes unified monitoring of multiple devices and automatically generates trend analysis reports and hierarchical early warnings.

Detailed Product Description

Integrating optoelectronic technology, oil-gas separation, intelligent sensing and edge computing, this new-generation transformer condition monitoring device adopts an integrated wall-mounted structure. No extra concrete foundation is required, and on-site installation can be completed without power cut. Only connection to the transformer oil sampling port, power supply and communication link is needed, with full deployment and commissioning finished within 2 hours.

The oil-gas separation unit applies vacuum bubbling principles with compact structure and self-adaptive degassing volume, featuring strong long-term operational stability and solving clogging and aging failures common to traditional membrane degassing units. The core detection module is fitted with fully digital microphones and high-stable light source drivers, containing no moving mechanical parts to avoid mechanical wear and vibration interference. The Mean Time Between Failures (MTBF) exceeds 100,000 hours.

The built-in edge diagnosis engine incorporates multiple industry-standard fault diagnosis models including improved Duval Triangle and Three-Ratio Method. It automatically analyzes monitoring data and outputs probability evaluation of fault types without manual calculation. The system supports comprehensive self-diagnosis; it resumes operation automatically after power failure or communication interruption with all historical data preserved, perfectly fitting unattended substation operation.

The equipment shell is made of stainless steel with IP66 ingress protection, and internal optical components are fully sealed and isolated. It operates stably in extreme temperatures ranging from -40℃ to 70℃ with reliable detection performance from frigid high-latitude areas to tropical hot regions, with a designed service life over 15 years.

Core Technical Parameters

Detection Item	Measuring Range	Measurement Accuracy
Hydrogen (H₂)	0~5000ppm	±0.5ppm or ±5% of reading
Methane (CH₄)	0~10000ppm	±4ppm or ±5% of reading
Ethane (C₂H₆)	0~10000ppm	±4ppm or ±5% of reading
Ethylene (C₂H₄)	0~10000ppm	±4ppm or ±5% of reading
Acetylene (C₂H₂)	0~5000ppm	±0.1ppm or ±5% of reading
Carbon Monoxide (CO)	0~10000ppm	±4ppm or ±5% of reading
Carbon Dioxide (CO₂)	0~10000ppm	±4ppm or ±5% of reading
Oxygen (O₂)	0~10000ppm	±5ppm or ±5% of reading
Nitrogen (N₂)	0~10000ppm	±5ppm or ±5% of reading
Moisture Content	0~100ppm	±1ppm or ±3% of reading
Overall Ingress Protection	IP66	—
Power Supply	100~240V AC 50/60Hz	—
Data Interface	IEC61850, MODBUS, Ethernet, RS485	—
Designed Service Life	≥15 years	—

Installation and benefits of continuous dga monitoring on power transformers

Installation Instructions

1. Site Survey: Professional technicians confirm oil sampling port, power supply and communication conditions on site before installation, and customize mounting brackets and pipeline schemes.
2. Deployment: Wall-mounted installation directly fixed on brackets or cabinets near transformers; no civil construction or power outage required.
3. Pipeline Connection: Link the equipment inlet port to the transformer sampling valve and route the outlet oil back to the transformer tank with full sealing inspection.
4. Power-On Commissioning: Connect power supply and communication cables, complete parameter configuration, degassing exhaust and baseline calibration.
5. Acceptance & Handover: The equipment runs continuously for 72 hours without abnormalities. Project acceptance is completed after deviation from laboratory oil chromatography data meets standard requirements.

Application Advantages

The continuous DGA monitoring system for power transformers collects real-time data of characteristic gases and moisture in oil round the clock, precisely predicting latent faults such as partial discharge, overheating and insulation degradation.

It eliminates the delay of traditional offline sampling inspection, helps power grids shift from periodic maintenance to condition-based maintenance, reduces unexpected failures and unplanned outages, cuts operation costs and prolongs transformer service life to secure stable power grid operation.

Reasons to Choose Our Products

1. We hold fully independent and controllable core technologies across the whole industrial chain, with over 40 authorized patents covering light source modulation, photoacoustic cell design, oil-gas separation and anti-interference algorithms. The product has passed Type Test Class A certification by China Electric Power Research Institute. As one of the earliest domestic manufacturers to realize large-scale commercial application of laser photoacoustic DGA devices, our core technical indicators reach international advanced level.
2. More than 5,000 units have been deployed and running stably in over 2,000 substations nationwide, including multiple UHV converter stations and digital substation pilot projects. Our system has helped customers detect over 300 potential faults in advance, cutting the unplanned outage rate of connected users by 37% and extending average equipment service life by over 4 years. Our clients include State Grid, China Southern Power Grid, major power generation groups and industrial enterprises.
3. We provide full-lifecycle exclusive services with a nationwide technical service network offering 7×24h support. We promise 1-hour response and 2-hour on-site arrival for emergency alarms, plus one free equipment calibration and performance inspection per year. The dedicated operation and maintenance platform enables remote equipment status monitoring and early anomaly prediction.
4. Highly customized services are available: customized sensor shielding solutions for strong electromagnetic interference on site, open secondary development interfaces for platform integration, and fusion analysis of DGA data with partial discharge, core grounding current and winding temperature measurement data. The lead time of fault early warning is extended from 24 hours to 72 hours, solving the industry pain point of high false alarm rates based on single-parameter judgment.

FAQ

Q1: Will installation affect normal transformer operation?

A1: Absolutely not. Installation requires no power outage. Piping is connected via the original oil sampling port, and oil samples flow back in a closed loop without changing transformer oil level or operating status, exerting zero impact on normal equipment operation.

Q2: Does the device require frequent later maintenance?

A2: DGA Online Monitoring adopts a consumable-free design, requiring no replacement of carrier gas, chromatographic columns or other components during operation. Only routine checks on external pipeline joints are needed every six months, with annual maintenance workload under 2 hours, which is much less than conventional oil chromatography devices.

Q3: Can monitoring data be connected to our existing monitoring platform?

A3: DGA Online Monitoring is fully compatible. The device natively supports mainstream power communication protocols and can be directly connected to grid PMS systems, local SCADA platforms and various intelligent operation & maintenance systems without extra conversion modules. Docking and debugging can be finished within one working day.

Q4: Can the equipment work properly under extremely low temperatures?

A4: DGA Online Monitoring has passed wide-temperature adaptability tests and is equipped with an internal temperature control module. It can start and operate normally at -40°C, satisfying outdoor installation requirements in frigid northern areas during winter.

Q5: What is the deviation between device test results and laboratory oil chromatography data?

A5: Test results fully comply with industry standard Q/GDW 10536-2021, with deviation less than 5% compared with laboratory testing, satisfying precision requirements for fault early warning and equipment condition evaluation.

Q6:How dga monitoring can prevent catastrophic transformer failure?

DGA transformer monitoring continuously analyzes dissolved fault gases in transformer oil to detect early signs of overheating and partial discharge, enabling timely maintenance to prevent severe transformer breakdown and power outages.

Q7:What gases does dga monitor in transformer oil and why?

DGA Online Monitoring tracks hydrogen, methane, ethane, ethylene, acetylene, CO, CO₂, oxygen and nitrogen dissolved in transformer oil. Produced from insulation deterioration, overheating and partial discharge, these gases allow DGA Online Monitoring to identify potential internal equipment faults at an early stage.