A high step-down DC-DC converter based on a three-port DC transformer (DCX) is proposed. A power flow path from the input port to the load port and a power flow path from the input port to the intermediate DC bus port are built using a three-port DCX. Voltage regulation of the load port is achieved using a Buck converter connected between the intermediate DC bus and the load port. Single- and two-stage hybrid power conversion structures are built using a high step-down DC converter. Part of the power is processed by a DCX through single-stage power conversion. The circuit topology, operating principle, and characteristics of the high step-down DC-DC converter are presented. A detailed analysis of the transformer and autotransformer in the three-port DCX is presented, and the transformer and autotransformer are implemented with an integrated planar magnetic core and PCB windings. The design considerations for the proposed converter are also discussed. The effectiveness and feasibility of the proposed converter are verified experimentally.

A three-phase dual-output rectifier and its control strategy are proposed for powering airborne low-frequency pulsed load. To address the impact of high peak pulsed power load such as high-power airborne radar on the limited-capacity power supply system of aircraft, a rectifier is designed to simultaneously provide two independently controlled DC outputs. The two DC outputs are used to power the DC bus for the conventional loads and low-frequency pulsed load, respectively, solving the problem of low-frequency pulsed load interfering with the stable operation of conventional loads under the traditional single DC bus power supply architecture. By allowing the DC bus voltage for the low-frequency pulsed load to fluctuate over a wide range, the volume, capacity, and weight of the bus decoupling capacitors are significantly reduced. The paper presents the circuit implementation of the dual-output rectifier, provides a detailed analysis of its operating principles, and proposes a PWM modulation strategy and control method tailored to meet the power distribution and regulation requirements of the two outputs. Finally, experimental results are provided to validate the feasibility and effectiveness of the proposed method.

With the continuous development of power supplies toward miniaturization, light weights, and high levels of integration, research on high-frequency resonant conversion based on planar magnetics is becoming extensive. Combining the soft-switching characteristics of resonant converters with those of wide bandgap devices, the switching frequency can be increase to the MHz range, and the power density of the entire system can be improved considerably. However, higher switching frequencies impose new requirements for the structural design, loss distribution, and common mode (CM) noise suppression of passive magnetic components. Herein, a thorough survey of the-state-of-the-art of planar magnetics in high-frequency resonant converters is conducted. Printed circuit board winding-based planar magnetics, magnetic integration, and power-loss optimization strategies are summarized in detail. Suppression methods for CM noise in high-frequency planar magnetics are also clarified and discussed. An insight view into the future development of planar magnetics for high-frequency resonant converters is presented.