Common transformer refers to a static electrical appliance used in a distribution system to transfer alternating current and alternating voltage according to the law of electromagnetic induction. Ordinary transformers are usually in the distribution network voltage class of 10-35kv, capacity of 6300kva and below directly to the end user power supply. Mining transformer is a movable complete set of power supply and transformation device, divided into Mining Transformer and mine flameproof transformer. The general type transformer for mining is used in places where there is coal dust and biogas without explosion risk, for power driving and lighting electricity, and the flameproof type transformer for mining is mostly used in places with explosion risk in mines. Convert 6kv,10kv power supplies into low voltage power supplies required for 400 (380), 693 (660), 1200 (1140), 3450 (3300) v coal mines. The shell of Mining Transformer is full corrugated, two side open cover type and upper open cover type structure, with high mechanical strength, low temperature rise, good heat dissipation effect and so on. Core selection of good low-loss silicon steel sheet, no-load loss is low, no-load current is small, low noise. With h class insulation material and advanced insulation structure, it has good thermal stability and can continue to run at full load at high temperature.