Toroidal transformer is a kind of step-up and step-down power supply device, which has the advantages of small volume, low noise, less heat and high performance. Generally, we use a variety of voltages, such as 220V for domestic lighting, 36V for industrial safety lighting, and the voltage of the welding machine needs to be adjusted. These cannot be separated from the toroidal transformer, which can step down the voltage we need through the principle of electromagnetic mutual inductance of the main and auxiliary coils. But how to improve the conversion efficiency of toroidal transformers has been a problem for many people. In fact, the conversion rate of a toroidal transformer is determined by the transformer's power, production materials, and its work site.