Preventing and Resolving High Temperature Issues in Diesel Generator Sets

High temperature-related failures in diesel generator sets rank among the top three failures in power systems, directly affecting the lifespan of the equipment and power supply safety. This article systematically analyzes the causes of high temperature and control mechanisms based on the GB/T 2820 standard and industrial scenario field data, offering practical technical solutions.

I. High-Temperature Cause Diagnosis Model

By analyzing over 300 generator failure cases, we developed a three-axis risk analysis model for high-temperature issues:

• Heat Source End (35%): Carbon build-up in the combustion chamber, fuel injection timing deviation, decreased turbocharger efficiency
• Heat Transfer End (50%): Insufficient coolant flow, radiator blockage >30%, pump impeller corrosion
• Environmental End (15%): Intake air temperature >45°C, altitude >2000m, insufficient ventilation rate in the engine room (<0.5m³/(s·kW))

II. Core Control Technologies

1. Precise Heat Management System ControlRadiator Optimization Plan:
   • Use tube-and-belt radiators (18% more efficient than fin-type radiators).
   • Tilt the radiator at a 5°-8° angle, utilizing gravity-based self-cleaning structure (measured 40% reduction in dust accumulation).
   • Install differential pressure sensors: automatic cleaning program triggered when the pressure difference between intake and exhaust exceeds 200Pa.
   Coolant Management:
   • Glycol concentration maintained between 40%-60% (freezing point -25°C to -60°C, boiling point 106°C-110°C).
   • Add 0.5%-1.2% DCA4 corrosion inhibitor (3x better cavitation resistance in cylinder liners).
   • Use handheld refractometer for monthly concentration testing, adjust immediately if deviation exceeds ±5%.
2. Intelligent Load Control SystemDynamic Power Distribution Technology:
   • Install MLC-2000 controller for real-time monitoring of cylinder exhaust temperatures (temperature difference ≤30°C).
   • When coolant temperature reaches 85°C, the system initiates a staged load reduction:
     • 85°C-90°C: Reduce load to 75%
     • 90°C-95°C: Reduce load to 50% and initiate auxiliary cooling
     • 95°C: Emergency shutdown.
   Sudden Load Surge Buffering Design:
   • Install supercapacitor modules in the ATS transfer cabinet (instant load surge capacity of 50%).
   • Use a doubly-fed speed regulation system to extend load response time to 8-12 seconds.
3. Lubrication System Efficiency EnhancementOil Circuit Intelligent Monitoring System:
   • Install online viscosity meters (range: 5-30 cSt) and ferrographic analyzers.
   • Alarm when oil viscosity change rate exceeds 15% or wear particle concentration exceeds 100ppm.
   Special Measures for High Altitude Areas:
   • Use SAE 5W-50 full-synthetic oil (viscosity at 100°C: 16.3 mm²/s).
   • Add pre-lubrication pumps to ensure oil pressure ≥0.25MPa during startup.

III. Maintenance and Management Standard Procedures

Routine Inspection Checklist:

Key Overhaul Control Points:

• Pump impeller gap: 0.3-0.5mm (over-tolerance reduces flow by 25%).
• Thermostat opening temperature: 82°C ±1.5°C (replace if deviation >3°C).
• Intercooler efficiency: Intake temperature reduction ≥25°C.

IV. Typical Failure Handling Cases

Case 1: Coastal Power Plant Generator Sustained High Temperature

• Symptom: 2000kW generator running at 92°C-95°C water temperature in summer.
• Diagnosis: Infrared thermography showed a 40°C temperature difference in the lower-left corner of the intercooler.
• Solution: Inspection revealed a 47% blockage due to shellfish attachments; used 3% citric acid circulating cleaning.
• Result: Intake temperature dropped by 28°C, fuel consumption reduced by 7.3g/kWh.

Case 2: Highland Mining Generator Power Sudden Decline

• Symptom: 3000m altitude generator operating for 1 hour, power reduced by 35%.
• Analysis: Atmospheric pressure of 70kPa caused air-fuel ratio imbalance and poor combustion.
• Modification: Added turbocharger compensation module (MAP sensor + ECU tuning).
• Result: Power restored to 98% of nominal, exhaust temperature dropped by 120°C.

V. Advanced Technology Applications

Phase Change Material (PCM) Cooling Technology:

• Embedded paraffin-based PCM materials in the cylinder liner water jackets (phase transition temperature 85°C-90°C). Real-world testing showed a 15% reduction in peak thermal load.

AI Fault Prediction System:

• Deployed LSTM neural network models to integrate vibration, temperature, and pressure multi-source data for 72-hour advance high-temperature warning (accuracy: 92%).

Hydrogen-Oxygen Catalytic Exhaust Temperature Reduction:

• Installed HHO generator in exhaust manifold, reducing tail gas temperature from 650°C to 530°C while cutting NOx emissions by 45%.

Conclusion

The thermal management of diesel generator sets is a systematic project, requiring a “monitoring-control-maintenance” three-tier defense system. We recommend conducting quarterly heat balance tests (in line with ISO 8528 standards) and utilizing intelligent operation and maintenance platforms for full lifecycle management. The solutions presented here have been validated in steel, data center, and other industrial environments, reducing the incidence of high-temperature failures by over 76%, demonstrating significant economic benefits.