The S13 type is an independently developed product based on the original S11 distribution transformer, incorporating new materials, processes, and a combination of self-innovation and technology introduction. By optimizing and innovating the core and coil structure, it aims to reduce no-load losses and noise. No-load losses have been reduced by an average of 37%, and noise levels have decreased by an average of 20% compared to the current national standard JB/T10088-2004, with the product's performance reaching an advanced level in China.