This type of power supply directly rectifies the AC power supply into DC power supply without using a power transformer, which greatly reduces the cost of power supply equipment and improves the efficiency of power supply equipment. It also greatly simplifies the power supply device of electronic equipment, reduces its volume and weight, and is easy to use and popularize. Electronic equipment such as amplifiers and radios can use this power supply. Using transformer-free rectifier in televisions can also eliminate the influence of the leakage magnetic field of the power transformer on the deflection magnetic field, so as to improve the stability of image quality.