What are the key design considerations for medium voltage (15kV class) distribution systems?

Medium voltage design considerations include: insulation coordination and BIL ratings, switchgear selection (air-insulated, SF6, vacuum), protective relaying with proper CT/PT ratios and relay coordination, cable selection with proper stress cone terminations and surge arresters, grounding methods (solidly grounded, resistance grounded, ungrounded) affecting fault behavior and equipment ratings, touch/step potential analysis for substations, and arc flash mitigation strategies for personnel safety. Maintenance access, switching procedures, and oil containment for transformers must be addressed.