The 500kV power transformer adopts the combination of Chinese and European technologies, and has the characteristics of no hanging core, anti-leakage, anti-rust, anti-short circuit, low loss, low noise, low temperature rise and low partial discharge. It is economical, reliable, simple and convenient to maintain, and meets the requirements of environmental protection, which creates favorable conditions for the realization of unattended power station. Three-dimensional electric field numerical calculation and simulation test of insulation structure are carried out with computer software. The leakage magnetic field, temperature field, noise mechanism and partial discharge are calculated theoretically. After that, products with good economic indicators, simple manufacturing process and high insulation reliability are designed.

The core of 500kV power transformer is made of high-quality silicon steel sheet with high magnetic conductivity and low loss coefficient, with high processing accuracy. The iron core structure adopts multi-step full oblique joint to reduce no-load loss. The winding is made of excellent oxygen-free semi-hard copper self-adhesive transposed conductor, which reduces the load loss of the transformer. The assembly tolerance of the body is reduced by using the process of assembling the winding first and then assembling it as a whole, so as to improve the overall strength of the body. The body is dried by kerosene gas phase, and the whole body is vacuum-immersed and oiled. The partial discharge level is significantly lower than the value specified in the national standard. The transformer performance conforms to European energy efficiency standards and Chinese energy efficiency standards.