In order to solve the problem of large volume and high weight of phase shifting transformers, which are necessary components in multi-pulse rectifiers. A parallel 18-pulse rectifier based on an electrical and electronic transformer is proposed, consisting of an electrical and electronic converter and a high-frequency multi-pulse rectifier. By using an electrical and electronic converter, the AC power frequency can be converted to a high frequency. Then, the phase-shifted through a phase transformer to form three sets of three-phase rectifier bridges for rectification. This chapter studies the working principle of power electronic transformers and formulates management strategies based on their working principle. After analysis, the coupling between input and output voltages of power electronic transformers is obtained through the operating mode under high-frequency conditions of rectifier bridges. The simulation results show that replacing traditional power frequency transformers with electronic transformers reduces the transformer volume by two-thirds, ensuring stable power quality and confirming the feasibility and accuracy of the theoretical analysis.