Installing the transformer inside the nacelle has the following advantages: saving land; contributing to the balance between the nacelle and the blades; after boosting by the transformer, smaller-sized cables can be used, and the power loss in high-voltage transmission is reduced; decreasing the yaw load. The nacelle transformer has a more compact structure, is maintenance-free, highly reliable, environmentally friendly, has a low curtailment rate of equipment, high power generation efficiency, and obvious economic benefits. It is the development direction of the wind power industry in the future.