Analîz û Pêşkarên Pirsgirêka Yek Serbistanina 145kV

1. Pêşnûmara

Di şebeka elektrîkî û taybetîn deyarkirîn Indonesîya de, dixweşên bi tenzurî 145kV (HVDs) ji bo pêk kirina parastîna baxta yên destpêkirîn li ser çarxeyên arkepelîk a wehatiyên. Lê, vêgirên nekparastînê tehdîdên mezin diha da ku stabîlîya şebekê biguheze. Vê nivîsê li ser vegirê ya maloperasyon a 145kV HVD di stasyona birkerrojî yekemîn Indonesîya deravet, anînên sereke dikareşin û piştgiriyan peyda bikin, heta biba standartên parastina IP66 û IEC 60068-3-3 reyaz bike da parastina operasyonan were zêde bike.

2. Tijîra Vegirê di Indonesîya de

Di mêsê Adar 2024 de, dixweşek 145kV di stasyona birkerrojî yekemîn Jawa Island de nekbeş bi karî nekparast di dema transfera beşdarîya rutîn de xelat hatî. Vegirê li ser stasyona birkerrojî yekemîn near Surabaya, ku kovera dixweşe IP66-rated hatiye navendî kirin da şertên tropikîn were qabul bikin. Vekeveka nekbeş bi bexwaş beşdarîyên 120,000 evîn werdigiribû û beşdarîyek 30MW were hevîkirin, da ku mehengên reparasyonê jêrîn $800,000 werdigiribû. Analîza pas-vegirê anînên sereke dikareşin ku peretînên şertîn û cemaletên kontrol sisteman werdigiribûn.

3. Analîza Anînên Sereke
3.1 Zêdetirîn Cemaletan Kontrol
3.1.1 Induksyonê Parazitî

Kirkirina DC kontrol dixweşek bi girîng komunîk û sisteman parastina şimşîr PLN însanî yên 145kV (rapora 2023). Di dema şimşîrên nebihîn de, overvoltages transîentî 12V DC spikes li ser kirkirina kontrol werdigiribûn, ku diyarî rastîn hatiye aktîfkirin dixweşek. Berîn ên vegireya 2022 Bali, ku ground loops 145kV HVD misoperation werdigiribû, vê kes û terewîn nekuşeyan kontrol û proteksyon cemaletan nîşand kir.

3.1.2 Rewşên Relê

Relêya elektromagnetîk dixweşek, ku ji bo 100,000 operaçiyonan reyaz kirin, ji bê guman 150,000 cycles beşdar nehatiye. Breakdown insulation relêya coil, ku bi autopsy post-fault werdigiribû, arcing allowed that normally open contacts bridged. Tests thermal cycling IEC 60068-3-3 later confirmed the relay's epoxy insulation degraded at >60°C, a common temperature in Indonesia's unairconditioned switchyards.

3.2 Degradationa Şertîn
3.2.1 Failure of IP66 Seal

Despite IP66 certification, the switch's EPDM gasket showed 3mm cracks, allowing salt mist ingress. Coastal air in East Java contains 0.05mg/m³ of chloride ions, accelerating corrosion. SEM analysis of the gasket revealed ozone cracking, a result of prolonged exposure to UV radiation (annual UV index >12) and humidity >85%. This compromised the enclosure's dust/water protection, with internal components showing 0.2mm rust deposits on copper contacts.

3.2.2 Insulation Degradation Caused by Moisture

High humidity (90% RH average) caused condensation on the switch's composite insulator, reducing surface resistivity from 10¹²Ω to 10⁸Ω. Partial discharge (PD) monitoring data showed PD activity increased from 5pC to 25pC over six months, a precursor to flashover. The insulator's hydrophobic coating, compliant with IEC 60068-3-3, lost effectiveness after three years in tropical conditions, failing to repel water films.

3.3 Maintenance Deficiencies
3.3.1 Inadequate Lubrication

The switch's mechanical linkage had insufficient silicone grease (NLGI Grade 2), leading to 15% increased friction in the operating mechanism. Temperature sensors recorded 40°C hotter than baseline in the pivot joints, causing stick-slip motion that generated mechanical shocks, mimicking normal opening commands. This aligns with PLN's 2024 report showing 43% of 145kV HVD maloperations relate to neglected lubrication.

3.3.2 Delayed Sensor Calibration

The switch's contact resistance sensor, calibrated to ±10μΩ, had not been verified for 18 months. Actual accuracy had drifted to ±35μΩ, masking a 120μΩ contact degradation (critical threshold: 150μΩ). Such delays in calibration are common in remote Indonesian substations, where 37% of 145kV HVDs lack scheduled maintenance due to logistical challenges.

4. Comprehensive Countermeasures
4.1 Control System Redesign
4.1.1 Isolated Grounding Architecture

Implement a star grounding system for 145kV HVD control circuits, separating them from lightning protection grounds by 5m. Install 1000V isolation transformers on control power feeds, as demonstrated in a 2023 case study in Medan that reduced transient-induced maloperations by 92%.

4.1.2 Solid-State Relay Upgrade

Replace electromagnetic relays with IEC 60950-certified solid-state relays (SSR) rated for 10⁷ operations. SSRs in a Semarang pilot project showed zero voltage spikes and 50% faster switching times, eliminating arcing risks in humid environments.

4.2 Environmental Resilience Enhancement
4.2.1 IP66 Seal System Overhaul

• Gasket Replacement: Use fluoroelastomer (FKM) gaskets with 200°C temperature resistance, 300% elongation, and UV stabilizers, meeting IEC 60068-3-3's tropical climate annex.

• Drainage Modification: Add 12mm weep holes with anti-insect screens to switch enclosures, reducing water pooling. A Jakarta trial showed this reduced internal humidity from 85% to 55% within 24 hours.

4.2.2 Advanced Insulation Solutions

• Superhydrophobic Coating: Apply aerosol - based SiO₂ coatings (contact angle >150°) to insulators, extending hydrophobicity from 3 to 7 years. Field tests in Bali reduced PD activity by 80%.

• Dehumidifier Integration: Install Peltier - effect dehumidifiers (3L/day capacity) in enclosures, maintaining <40% RH. A Sulawesi substation saw contact resistance stability improve by 65% post - installation.

4.3 Predictive Maintenance Optimization
4.3.1 IoT - Enabled Monitoring

Deploy a 4G - enabled sensor network measuring:

• Contact resistance (0.1&mu;&Omega; resolution)

• Mechanism vibration (100Hz - 10kHz bandwidth)

• Enclosure humidity/temperature (&plusmn;1% RH, &plusmn;0.5&deg;C)

Data is analyzed via a cloud - based AI platform (accuracy 94%) that predicts failures 72 hours in advance, as proven in a Papua pilot project that cut unplanned outages by 85%.

4.3.2 Regionalized Maintenance Schedules

Develop climate - based maintenance plans:

5. Technical and Economic Impact
5.1 Reliability Metrics Improvement

• MTBF Increase: From 12,000 hours to 45,000 hours post - intervention, exceeding IEC 62271 - 102's target.

• Fault Detection Time: Reduced from 4 hours to 15 minutes via real - time IoT monitoring.

5.2 Cost - Benefit Analysis

• Initial Investment: $500,000 for a 10 - switch substation in Indonesia

• 5 - Year Savings: $2.3 million from:

• 75% reduction in maintenance labor

• 90% decrease in equipment replacement costs

• 88% minimization of downtime losses

6. Conclusion

The 145kV disconnect switch maloperation in Indonesia underscores the need for integrated solutions addressing control system vulnerabilities, environmental degradation, and maintenance gaps. By implementing IP66 - enhanced enclosures, IEC 60068 - 3 - 3 - compliant components, and IoT - driven predictive maintenance, Indonesia's 145kV grid can achieve reliability metrics on par with global standards. This approach not only mitigates maloperation risks but also supports the country's goal of a resilient, smart power infrastructure capable of meeting rising energy demands in tropical environments.