Abstract: In severe cold areas, low temperature, high humidity, load mutation and standby switching may jointly cause condensation in low-voltage cabinets, contact-resistance increase, pump overload and control-loop maloperation. Taking a heat-exchange station in a severe cold area as the engineering object, a low-temperature risk grading model based on environment, load and equipment status is established. A combined guarantee scheme including cabinet micro-environment regulation, staggered pump start-stop, fast standby power switching and predictive maintenance is proposed. The results show that the comprehensive risk index of key equipment decreases from 0.63 to 0.29, and the alarm response time is reduced by about 42%, which improves the continuous winter operation capability of the heating electrical system.