LOW VOLTAGE APPARATUS ›› 2024, Vol. 0 ›› Issue (5): 20-29.doi: 10.16628/j.cnki.2095-8188.2024.05.003

• Research & Analysis • Previous Articles     Next Articles

Research on Topology and Control Strategy for Pulsed Load Two-Stage DC-DC Power Supply

ZHANG Seng1, CAO Xuan2, TAN Yunfei2, ZHAO Zhihong2   

  1. 1. Power Science Research Institute of State Grid Jiangsu Electric Power Co.,Ltd., Nanjing 210000, China
    2. Nanjing University of Science and Technology, Nanjing 210000, China
  • Received:2023-12-25 Online:2024-05-30 Published:2024-06-25

Abstract:

In order to meet the requirements of high power density and high dynamic response performance of pulse-load DC converter,a two-stage DC converter applied to pulsed load is studied.Among them,the three-level synchronous rectifier buck converter with smaller filter inductance and higher system loop bandwidth is selected as the pre-stage converter,and the DCX (DC Transformer)-LLC resonant converter is selected as the post-stage converter,which has more advantages in dynamic response and efficiency than the closed-loop control LLC.Then,a soft-start strategy to optimize the voltage stress problem of TL(Three Level)-Buck switch is proposed,which solves the problem that the flying capacitor voltage drops to a very low level after charging in the soft-start stage.Finally,the proposed closed-loop and soft-start control strategies of two-stage DC converters are verified by simulation and experiments,and it is determined that the soft-start strategy can optimize the voltage stress of the switch during the start-up of the pre-stage TL-Buck.

Key words: pulsed load DC converter, pulsed power balance, two-stage architecture, fast dynamic response

CLC Number: