Abstract: China has a vast territory and complex climate, where extreme temperatures, strong winds, sandstorms, earthquakes, and high-altitude conditions pose serious challenges to the safe operation of substations. Traditional fixed design models exhibit poor adaptability and high disaster prevention costs. In response, this paper innovatively proposes a "3×2×2×N building-block" modular disaster prevention design system for substations. By flexibly combining three outgoing line schemes, two reactive power compensation modules, two wind?sand prevention modules, and one expandable functional space, the system constructs a substation solution that can be rapidly configured for specific hazard environments. It achieves comprehensive, multi?level disaster prevention covering electrical layout, structural protection, and intelligent operation and maintenance. Compared with conventional design schemes, this system significantly enhances the disaster resilience of substations, reduces operational costs, and provides systematic technical reference and feasible engineering pathways for the construction of power facilities in high?risk disaster areas.