📋 Case Study
Distribution Network Reinforcement
Excessive voltage drop (>8%) on 400 V feeders during evening EV charging peaks; neutral conductor overheating
🏗️ Project Overview
Urban LV/MV network upgrade in aging city district with rising EV charging demand
🎯 Challenge
Excessive voltage drop (>8%) on 400 V feeders during evening EV charging peaks; neutral conductor overheating
🔧 Design Approach
Three-phase unbalanced load flow with detailed cable modeling, including skin effect and neutral current harmonics; dynamic load profiling based on smart meter clusters
📐 Design Diagram
AI-generated project design illustration
📐 Key Calculations
Neutral Current Magnitude
|I_N| = √(I_a² + I_b² + I_c² − I_a·I_b − I_b·I_c − I_c·I_a)
Result: 182 A
Exceeded 150 A rating → prompted neutral doubling
Feeder Voltage Drop (Unbalanced)
ΔV_ph = I_a·Z_aa + I_b·Z_ab + I_c·Z_ac
Result: −34.2 V (Phase A)
Validated need for distributed SVG at mid-feeder
📊 Results
Max voltage drop reduced from −38.5 V to −6.1 V; neutral temperature reduced by 22°C; feeder loading normalized to <72% peak💡 Lessons Learned
- •Balanced load flow grossly underestimates neutral stress—unbalanced modeling is non-negotiable for modern distribution
- •EV clustering requires time-synchronized load profiles—not static diversity factors
✅ Key Takeaways
- 1Balanced load flow grossly underestimates neutral stress—unbalanced modeling is non-negotiable for modern distribution
- 2EV clustering requires time-synchronized load profiles—not static diversity factors
📐 Prerequisites
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