📋 Case Study

Underground Copper Mine DC Fast-Charging Hub (Chile)

Limited space in existing service drift; seismic zone requiring vibration-isolated mounting; strict MSHA Class I Div 2 hazardous area compliance

🏗️ Project Overview

Installation of 12× 350 kW DC chargers for 40-ton haul trucks at El Teniente

🎯 Challenge

Limited space in existing service drift; seismic zone requiring vibration-isolated mounting; strict MSHA Class I Div 2 hazardous area compliance

🔧 Design Approach

Modular pre-fab charging cavern with explosion-proof enclosures, redundant grounding, and fiber-optic isolated control network; 1500 V DC architecture with active harmonic filtering

📐 Design Diagram

Service Drift (Existing) Modular Charging Cavern EP Enc. EP Enc. Seismic Mount (0.4g → 2.4×) 1500 V DC Fiber-Optic Isolation Redundant Grounding Zloop = 0.18 Ω MSHA Class I Div 2 Compliant Limited Space Seismic Zone

AI-generated project design illustration

📐 Key Calculations

Ground Fault Loop Impedance

2 × Conductor Length × Resistivity / Cross-Section
Result: 0.18 Ω
Meets IEC 61851-23 <0.2 Ω requirement

Seismic Mounting Load Factor

Static Load × Seismic Coefficient (0.4g)
Result: 2.4× design load
Validated via ANSYS structural simulation

📊 Results

Zero charging-related incidents over 22 months; 99.2% charger uptime; 27% faster turnaround vs. diesel refueling

💡 Lessons Learned

  • Pre-certified explosion-proof components accelerated commissioning by 11 weeks
  • Harmonic filters reduced transformer heating by 18°C
  • Remote diagnostics cut mean time to repair from 4.2 hrs to 38 min

Key Takeaways

  • 1Pre-certified explosion-proof components accelerated commissioning by 11 weeks
  • 2Harmonic filters reduced transformer heating by 18°C
  • 3Remote diagnostics cut mean time to repair from 4.2 hrs to 38 min