Partial Discharge Monitoring with Temperature Monitoring — Methods, Correlation, and Sensor Selection

• Key idea: Menggabungkan pemantauan pelepasan sebagian dengan pemantauan suhu exposes both electrical and thermal stress, mengaktifkan lebih awal, high-confidence transformer diagnostics.
• Why it works: Most insulation failures involve a mix of PD activity and localized overheating; trending both signals eliminates blind spots and reduces false positives.
• Sensor highlight: Sensor suhu serat optik neon provide true winding and hot-lug temperatures with dielectric isolation and immunity to EMI, outperforming RTD/thermocouple and infrared-only methods in high-voltage environments.
• System view: Integrate UHF/TEV/HFCT PD sensors, probe suhu serat optik, Penganalisis DGA, Dan SCADA/IoT dashboards for a unified health index and predictive maintenance.

Daftar isi

1. What Is Partial Discharge Monitoring
2. Why Combine Temperature Monitoring
3. PD–Temperature Correlation and Failure Signatures
4. Types of PD Sensors
5. Temperature Monitoring Methods Compared
6. Why Fluorescent Fiber Optic Sensors Win in HV Assets
7. Recommended Alarms, Ambang batas, and Event Logic
8. Arsitektur: Akuisisi Data, Analisis, and SCADA/IoT
9. Kasus Penggunaan: Gardu Induk, Pabrik Industri, Energi terbarukan
10. Practical Deployment Checklist
11. Pertanyaan Umum
12. About Our Monitoring Solutions

1. What Is Partial Discharge Monitoring

Debit sebagian (PD) is a localized electrical breakdown within insulation that does not bridge the electrodes completely. PD erodes solids, carbonizes surfaces, and accelerates aging until a full dielectric failure occurs. Pemantauan pelepasan sebagian captures these events in real time so operators can intervene before damage propagates.

1.1 Why PD Matters

• It is the earliest electrical symptom of insulation distress.
• It correlates strongly with contamination, kekosongan, and surface tracking risks.
• Its trends (count, besarnya, PRPD patterns) help classify defect types.

1.2 Where PD Is Measured

• Inside the tank (radiated UHF) and on grounded structure (TEV).
• On cable screens/earths using HFCT clamps for conducted pulses.
• Near bushings, terminasi kabel, and winding leads where fields are strongest.

2. Why Combine Temperature Monitoring

Many incipient faults blend stres listrik (PD) dengan stres termal (titik panas). Tracking PD without temperature can misclassify benign corona; tracking temperature without PD can miss dry-band or void discharge. A combined approach confirms severity and guides precise maintenance actions.

2.1 Benefits of a Combined Strategy

• Higher diagnostic confidence: PD rise with concurrent hot-spot increase indicates an escalated failure path.
• Root-cause clarity: Temperature-only rise at a single lug suggests a mechanical or contact issue, not insulation voids.
• Actionable maintenance: Decide between cleaning/re-termination, penurunan beban, or planned outage based on both signals.

2.2 Typical Combined Outcomes

PD Trend	Temperature Trend	Likely Scenario	Suggested Action
Kenaikan	Kenaikan	Listrik + thermal stress compounding	Short-term derate, schedule inspection, prepare outage plan
Kenaikan	Stable	Surface/void discharge without major heating	Targeted cleaning, re-insulation, monitor closely
Stable	Rising at one lug	Loose/oxidized connection (pemanasan I²R)	Tighten/clean lug, verify torque, re-baseline
Stable	Rising overall	Cooling degradation, kelebihan muatan, ambient spike	Fan/pump check, load control, thermal audit

3. PD–Temperature Correlation and Failure Signatures

Berkorelasi PD magnitude/count dengan hot-spot and terminal temperatures separates nuisance events from critical defects. Add humidity, memuat, and dissolved gas trends for a multi-dimensional health picture.

3.1 Signature Examples

• PD bursts aligned with RH spikes: Surface tracking from condensation on terminations.
• PD growth with hot-spot drift during load steps: Insulation void aggravated by thermal expansion.
• Hot-lug delta without PD rise: Mechanical looseness or corrosion (resistensi kontak).

3.2 Analytics Tips

• Menggunakan tingkat kenaikan (ΔT/Δt) Dan peer-delta (lug-to-lug ΔT) to detect fast thermal faults.
• Kecenderungan PRPD patterns under different loads to classify discharge types.
• Cross-check with Analisis DGA (H₂, C₂H₂, C₂H₄) to confirm electrical vs. thermal root cause.

4. Types of PD Sensors

Kuat pemantauan pelepasan sebagian system blends radiated and conducted measurement channels to capture diverse defects.

4.1 Sensor UHF

• Detect radiated electromagnetic energy from PD events in the UHF band.
• Best for metal-clad equipment, tank, and GIS proximities.
• Low noise susceptibility; supports time-of-arrival localization with multiple antennas.

4.2 TEV Sensors

• Ukuran Transient Earth Voltages induced on metal surfaces by internal PD.
• Useful for switchgear panels and transformer tanks; cepat, tidak mengganggu.

4.3 Sensor HFCT

• Penjepit Transformator Arus Frekuensi Tinggi measure PD pulses on grounds/cable screens.
• Good for cable terminations and earthing conductors; simple retrofit.

5. Temperature Monitoring Methods Compared

Temperature monitoring closes the diagnostic loop, but methods vary widely in suitability for high-voltage assets. The matrix below compares practical options for transformers and substation equipment.

Metode	Prinsip	Kekuatan	Keterbatasan	Penggunaan Terbaik
Serat optik neon	Optical fluorescence decay at the probe tip	Dielektrik, kebal terhadap EMI; true hot-spot; respon cepat; safe near HV	Requires careful probe routing and handling	Winding hot-spots, busing, terminal lugs
RTD / PT100	Resistance changes with temperature	Biaya rendah; mature technology; easy to source	kerentanan terhadap EMI; galvanic paths; less ideal near HV fields	Cabinet ambient, radiator oil, saluran
Termokopel	Thermoelectric voltage difference	Jangkauan luas; inexpensive; small form factor	Noise sensitivity; reference junction drift in HV sites	General-purpose surfaces away from HV
Infrared camera (handheld)	Surface IR emission imaging	Rapid survey; no contact; visual hotspots	Tidak terus menerus; operator dependent; emissivity errors	Periodic audits and commissioning checks
IR window + routine scan	Fixed IR viewport on enclosure	Safer scanning without opening doors	Still periodic; limited field of view	Switchgear and cabinet hotspots
Wireless IoT spot sensors	Battery BLE/LoRa node on surface	Easy retrofit; basic trending	Battery maintenance; RF reliability in metalwork	Auxiliary surfaces in non-critical zones

5.1 Practical Takeaways

• Untuk true winding hot-spot Dan HV proximity, memilih serat optik fluoresen.
• Use RTD/PT100 for ambient and oil context; rely on fiber for risk decisions.
• Keep infrared as a supplementary survey tool, not the primary protection channel.

6. Why Fluorescent Fiber Optic Sensors Win in HV Assets

Sensor suhu serat optik neon excel where electrical sensors struggle. They bring measurement directly to energized, high-field regions without introducing conductive paths or EMI errors. That makes them the preferred choice for correlating aktivitas PD dengan true hot-spot temperature in transformers and high-voltage switchgear.

6.1 Keuntungan Teknis

• Dielectric safety: No metal conduction from probe to conditioner; inherently HV-safe.
• kekebalan EMI: Immune to magnetic and electric field interference; stable during switching events.
• Hot-spot fidelity: Direct contact at windings, terminal lugs, or bushing flanges captures the temperature that matters.
• Fast dynamics: Millisecond-scale response supports tingkat kenaikan alarms for arc-prevention.

6.2 Integration Advantages

• Multipoint arrays feed a monitor digital transformator di samping UHF/TEV/HFCT sensor PD.
• Correlates with Penganalisis DGA readings for three-way confirmation of fault type.
• Communicates over Modbus TCP/RTU, IEC 61850, atau MQTT to SCADA/IoT dashboards.

7. Recommended Alarms, Ambang batas, and Event Logic

Establishing intelligent alarm logic ensures that pelepasan sebagian (PD) Dan pemantauan suhu systems deliver actionable insights rather than excessive nuisance alerts. The system should compare both PD and temperature data streams and use correlation-based triggers for event classification.

7.1 PD Alarm Thresholds

Tingkat Keparahan	Typical PD Magnitude (pc)	Tindakan yang Direkomendasikan
Normal	0 – 100	Continue routine monitoring
Peringatan	100 – 300	Increase measurement frequency, verify temperature trend
Kritis	>300	Schedule inspection and correlate with DGA & kenaikan suhu

7.2 Temperature Alarm Levels

• Pra-alarm: +10°C above baseline winding temperature — alerts operator for thermal deviation.
• Alarm: +20°C above baseline — initiate cooling fan or load reduction.
• Perjalanan: +30°C above baseline — trigger automatic protection relay to avoid insulation damage.

7.3 Correlation Event Logic

The logic below enhances the predictive accuracy of the monitoring system:

• kenaikan PD + Temperature rise → Confirmed defect, probable insulation breakdown.
• kenaikan PD + Constant temperature → Corona or surface discharge, low severity.
• No PD + Temperature rise → Overload or cooling malfunction.

8. Arsitektur: Akuisisi Data, Analisis, and SCADA/IoT

Itu combined PD and temperature monitoring system forms part of an integrated diagnostic platform. It connects multiple sensors to a central processor that performs real-time signal conditioning, data fusion, and communication to supervisory systems.

8.1 Hardware Layout

• PD acquisition unit: Accepts inputs from UHF, TEV, and HFCT sensors.
• Temperature acquisition unit: Accepts analog 4–20 mA / 0–5 V signals and fiber optic sensor channels.
• Processor module: Correlates PD pulse counts with thermal profiles.
• Communication module: Ethernet (RJ45), RS-485, or optical fiber using IEC 61850 atau Modbus TCP.

8.2 Software and Analytics

The system dashboard visualizes temperature curves, PD activity plots, and event alarms. It may employ predictive models to assign a health index to each transformer or switchgear bay. Cloud-based analytics further allow multi-site comparison for utilities and OEM manufacturers.

8.3 Integration Example

Di sebuah 220 kV substation in Vietnam, PD sensors and fiber optic probes feed a digital monitor communicating via IEC 61850 to the main SCADA. The system automatically issues warnings when PD pulses exceed 250 pC with simultaneous hot-spot acceleration above 15 °C/min.

9. Kasus Penggunaan: Gardu Induk, Pabrik Industri, Energi terbarukan

Combined PD and temperature monitoring has become essential across various industries to maintain uptime and ensure electrical asset safety.

9.1 Power Substations

Di gardu induk, PD sensors detect internal insulation degradation in transformator Dan switchgear GIS. Temperature monitoring ensures cooling efficiency and early identification of contact heating or loose connections. Integration with SCADA enables automated fault trending.

9.2 Industrial and Manufacturing Plants

Facilities operating under heavy load—steel mills, pabrik petrokimia, and cement factories—benefit from combined PD-temperature systems that safeguard mission-critical distribution transformers and motor control centers. Operators can schedule targeted maintenance based on data rather than time intervals.

9.3 Instalasi Energi Terbarukan

In wind farms and solar substations, kompak digital monitors track PD and thermal anomalies caused by harmonic distortion or inverter switching noise. Fiber optic temperature sensors offer precise, low-maintenance monitoring inside transformer nacelles and inverter housings where conventional sensors fail due to EMI.

10. Practical Deployment Checklist

• Perform baseline PD and temperature tests before energization.
• Install UHF/HFCT sensors on key transformer and cable locations.
• Mount fluorescent fiber optic probes at top oil, lekok, and terminal positions.
• Integrate outputs via Modbus TCP atau IEC 61850 to SCADA/IoT dashboard.
• Define alarm thresholds and correlation logic for automatic alerts.
• Train maintenance staff to interpret PRPD and thermal patterns for preventive action.

11. Pertanyaan Umum

Q1. Why is partial discharge monitoring essential for transformers?

Because PD is the earliest indication of insulation weakness. Continuous PD monitoring enables predictive maintenance and prevents catastrophic failures that could cost millions in downtime.

Q2. How does temperature monitoring complement PD detection?

Temperature data reveals thermal stress and load effects. When correlated with PD trends, it distinguishes between harmless corona and destructive insulation breakdowns.

Q3. What makes fluorescent fiber optic sensors superior?

They are non-konduktif, kebal terhadap EMI, and measure true hot-spot temperatures directly on windings or terminals. Unlike RTDs or thermocouples, they do not require galvanic isolation or suffer from electrical noise in HV environments.

Q4. Can PD and temperature data be integrated into one platform?

Ya. Modern monitor digital transformator support both data types through unified software, enabling real-time correlation, event classification, and SCADA integration via IEC 61850 Dan Modbus TCP.

Q5. Where has this system been implemented?

Projects across Malaysia, Indonesia, dan Arab Saudi use combined PD-temperature monitoring for power utilities and industrial plants, resulting in fewer unplanned outages and improved asset lifespan.

12. About Our Monitoring Solutions

We manufacture transformer and switchgear monitoring systems mengintegrasikan sensor pelepasan sebagian, probe suhu serat optik fluoresen, Penganalisis DGA, Dan IoT/SCADA gateways into one platform. Our equipment meets international standards including IEC 61850, ISO 9001, Dan CE sertifikasi.

We supply to utilities and OEM partners throughout Southeast Asia and the Middle East, menawarkan Kustomisasi OEM/ODM, full documentation, dan dukungan teknis. Contact us for datasheets, spesifikasi, and integration solutions tailored to your application.

13. Studi Kasus: Malaysia Industrial Substation Upgrade

Di dalam 2024, a large industrial complex in Selangor, Malaysia retrofitted its 132 kV distribution transformers with a combined partial discharge and temperature monitoring system. The goal was to reduce downtime caused by insulation faults and contact heating within oil-immersed transformers.

13.1 Latar belakang

The facility had previously relied on handheld DGA kits and monthly infrared thermography, which often missed intermittent PD spikes and temperature surges. After several unexpected shutdowns, management approved an upgrade to a real-time digital monitoring platform.

13.2 Penerapan Sistem

• Sensor UHF PD mounted on the transformer tank for internal discharge detection.
• sensor HFCT installed on neutral grounding leads to detect conducted pulses.
• Probe suhu serat optik neon embedded in high-voltage windings and top-oil locations for hot-spot measurement.
• Digital monitor with 7-inch HMI connected via Modbus TCP to the site SCADA system.

13.3 Hasil

Parameter	Before Installation	After Installation
Unplanned outages per year	5	1
Average maintenance cost reduction	–	30%
Transformer lifespan extension	–	Diperkirakan +8 bertahun-tahun
Detection of minor PD events	petunjuk (missed 80%)	Automatic 24/7 (99% capture)

13.4 Operator Feedback

After integration, maintenance engineers could visualize PD pulse density and real-time temperature curves side by side. When PD magnitude exceeded 250 pC and the fiber optic probe detected a rapid 10 °C/min increase, the system issued automatic alarms. Corrective actions were taken before any insulation failure occurred.

14. Studi Kasus: Indonesia Utility Substation (PLN)

Di dalam 2023, PLN (Indonesia’s national utility) deployed hybrid monitoring systems across its 70 kV substations in Sumatra and Java. The tropical climate posed high humidity and contamination risks, leading to partial discharges and accelerated insulation aging.

14.1 System Overview

• PD Sensors: Combination of HFCT and TEV sensors at switchgear cubicles.
• Sensor Suhu: Fluorescent fiber optic probes and RTD sensors on oil radiators for redundancy.
• Komunikasi: Fiber-optic Ethernet with IEC 61850 protokol, connected to regional SCADA center.

14.2 Operational Insights

Real-time PD and temperature trends revealed seasonal patterns: PD intensity spiked during monsoon months due to surface condensation, while temperature deviations highlighted radiator efficiency loss. Maintenance teams optimized cleaning schedules and replaced a faulty cooling fan before a severe failure.

14.3 Manfaat Utama

• Detected PD growth before insulation puncture.
• Reduced manual inspection frequency by 60%.
• Achieved higher reliability index (SAIDI improved by 25%).

15. Comparative Summary: Technology vs. Keuntungan

Teknologi	Fungsi Utama	Keuntungan Utama	Impact on Reliability
Sensor Serat Optik Fluoresen	Real-time winding temperature monitoring	Dielectric safety, kekebalan EMI	Eliminates false hot-spot readings
Sensor PD UHF	Detect internal partial discharges	High sensitivity to internal voids	Predicts insulation breakdown early
Sensor HFCT	Measure PD current pulses	Simple retrofit for cables/grounds	Complements radiated PD channels
DGA Analyzer	Detect gas evolution from faults	Identifies electrical & thermal fault type	Correlates PD/temperature trends chemically
Digital Monitor (SCADA)	Penggabungan data, alarm, visualisasi	Unified platform for multiple signals	Enables predictive maintenance

16. Global Adoption and Standards

Utilities in Europe, Timur Tengah, and Asia are converging toward integrated PD–temperature systems. Countries such as Germany, UEA, and Vietnam have included fiber-optic and PD diagnostics in new transformer procurement specifications, aligning with IEC 60076, IEC 60270, Dan IEEE C57.143 standar.

16.1 Typical Compliance Features

• Sensor calibration traceable to ISO 17025.
• EMC/EMI test certification under IEC 61000.
• Secure network integration using IEC 61850 MMS.

16.2 Future Outlook

As utilities pursue predictive maintenance and AI analytics, combining PD, suhu, and vibration data will form the backbone of pemantauan transformator cerdas ecosystems. Systems supporting cloud integration and machine learning will further enhance diagnostic precision.

17. Integration with Predictive Analytics Platforms

Modern transformer analytics platforms collect continuous PD, suhu, and gas data streams. Advanced algorithms calculate a Transformer Health Index (THI), providing a clear numerical score for asset condition.

17.1 Alur kerja

1. Sensor data acquisition (PD, suhu, DGA).
2. Feature extraction (PD amplitude, ΔT, gas ratio).
3. Machine learning model predicts probability of failure.
4. Alarm thresholds adapt dynamically to load and weather.

17.2 Benefits for Utilities

• Reduces unplanned maintenance by 40–60%.
• Extends transformer service life through condition-based actions.
• Centralized cloud dashboards allow fleet-wide monitoring.

18. Recommended Monitoring Package

For utilities and OEMs seeking complete diagnostic coverage, a recommended solution includes the following integrated modules:

• PD Detection: UHF, HFCT, and TEV sensors with local amplifier unit.
• Pemantauan Suhu: 4–8 channels of fluorescent fiber optic probes.
• DGA Module: Online dissolved gas analysis for hydrogen and hydrocarbons.
• Humidity Sensor: Measures ambient and internal relative humidity.
• SCADA Gateway: Modbus TCP/RTU + IEC 61850 for remote data exchange.
• Alarm Interface: Configurable relay outputs and email/SMS notifications.

18.1 Example Specification (for reference only)

Input Channels	4–20 mA, 0–5 V, serat optik
Komunikasi	Ethernet RJ45, RS-485, serat optik
Catu Daya	AC 220 V ±10%, 50 Hz
Consumption	≤ 50 W
Lingkungan	-20 °C ~ +70 °C, 95% RH non-kondensasi

(All specifications are reference only — actual configuration depends on current product data sheets.)

19. Mengapa Memilih Solusi Kami

As a professional manufacturer of sistem pemantauan transformator, we integrate deteksi pelepasan sebagian Dan pemantauan suhu technology into one certified platform. Our systems have been installed in over 500 substations worldwide, supporting power utilities, OEM transformer factories, and industrial energy users.

• Factory-level R&D with complete ISO 9001 / CE / RoHS sertifikasi.
• Dukungan untuk OEM / ODM customization and turnkey engineering service.
• Comprehensive documentation and integration support with existing SCADA.

20. Kontak & Konsultasi

We welcome inquiries from produsen transformator, kontraktor EPC, and utility operators across Southeast Asia and the Middle East. Contact our engineering team to obtain:

• Technical documentation and CAD drawings.
• Quotation and lead-time for full monitoring systems.
• Guidance on integrating PD and temperature diagnostics into your transformers.

We are the original factory manufacturer—fully certified, experienced in large-scale monitoring projects, and committed to delivering long-term transformer reliability solutions.