Research And Design Of VRM Converter With Soft-switching And Poly-phase Interleaving Technology

Voltage regulator module(Voltage Regulator Module VRM) is used for fast microprocessor power DC / DC power modules. Its trend for output low voltage, high current, fast transient response, low ripple voltage, power small in size, high operating frequency, high efficiency and reliability.Based on the development of technology and application requirements to VRM, thesis designs a voltage regulation modules with 48 V input, 1.2V / 150 A output.On the basis of the demand for microprocessor to VRM performance analysis, the paper estibulishes the overall design scheme: the main circuit using "Asymmetric Half-bridge+ Multiphase Interleaved Parallel SR-Buck" two-stage conversion topology,control circuit in a compound controlled manner. Pre-main circuit design using soft-switching technology to effectively solve the problem of high frequency switching losses,it can reduce circuit losses. Post-main circuit with synchronous rectification, multiphase interleaved and parallel current three key technologies. After the introduction of synchronous rectification,circuit reduces the output loss; Interleaved technology reduce the output filter inductor, capacitor capacity, increasing the output of the dynamic response speed; The application of parallel current technology is to solve the problem of currents uneven distribution in unit circuit caused by interleaved technology,which can effectively improve the reliability of the converter.In the aspact of high-frequency transformer design, the use of secondary winding turns ratio adjustment to eliminate the transformer DC bias current, which can effectively solve the DC bias magnetic phenomena caused by transformer volt-second product of the positive and negative imbalance. Based on parameter calculation and control circuit design in pre-stage and post-stage circuit, then adopting Saber and MATLAB / Simulink simulation software for modeling and simulation, results verify the correctness of the theoretical analysis and the feasibility of design scheme.Simulation results show that: VRM output voltage of 1.201 V, voltage ripple coefficient is 0.15%; total output current for 150.01 A, current ripple coefficient is 0.2%;efficiency up to 89.7%; meet the design reqirements.