Research On Output Dynamic Response Of DC/DC Converter With Impulse Load

Improving dynamic performance of DC/DC converter is currently a research hotspot and is the requirement in high load rate applications. In the power supply of vehicle, microprocessor and communication, the dynamic response requirements are very stringent for the power supply of electrical equipment, such as vehicle, microprocessor and communication. In order to ensure the normal operation and safety, converter output voltage should be sufficiently stable and keep the voltage overshoot caused by load mutation in the operating voltage range. The measure of parallel capacitors seriously affected the reliability and power density of supply system. Hence, the research of DC/DC converter with good dynamic response has great significance.Measures of improving DC/DC converter dynamic response are analyzed and summarized. Different strategies and power topologies have been presented. Four kinds of power topologies with different structure and principle were analyzed based on system complexity, efficiency and dynamic performance. Different strategie s were analyzed based on system complexity and dynamic performance. C ombining the problems and applications of various measures, this paper selects four-phase interleaved Buck Converter with coupling inductor as the basic topology, and AVP control strategy is used to further optimize the dynamic response of the converter.The operating characteristics of four-phase interleaved Buck Converter and the relationship between inverse coupled inductor and dynamic response are given out. The small signal model of Buck converter in CCM mode is established depending on the state-space average method. To simplify the analysis and design, the multiphase model replaced by equivalent single phase model. Various factors that affect converter dynamic response are discussed and analyzed, which contributes to parameter calculation and system design.The simulation of presented converter has been completed with Matlab/Simulink-PLECS, which can verify the feasibility of topology and control strategy. According to design indexes, the parameters and components in the converter are determined.Based on above analysis and simulation, a 12V/60 A experimental prototype is developed. Experimental results show that, under impulse load, the output voltage ripple meets design target and the converter achieves good dynamic response.