Design And Research Of 2kW Phase-Shifted Full-Bridge Soft-Switching Digital Control Module Power Supply

With the development of power electronics technology,modular power supply,as the heart part of power equipment,has become a core component of power equipment,and has been more and more widely used in the field of national defense,such as aerospace,radar,missiles,etc.However,the continuous change of application scenarios and the improvement of performance requirements have put forward higher requirements for the stability,safety,power density and efficiency of the module power supply.However,there is still a certain gap between China’s current research and development level in this field and foreign countries,especially the high power density high-power module power supply products that rely on imports.In addition,independent research and development also faces issues of key technology lockdowns and device embargoes,leading to challenges in achieving domestic manufacturing of high power density module power supplies with wide input.Therefore,promoting technological innovation and independent research and manufacturing in this field is of great significance.In order to improve power density and efficiency within a limited volume,it is necessary to consider both control strategies and hardware design.For this purpose,the paper selects a phase shifted full bridge converter as the research object based on the technical specifications of power supply products.The main research content of this article is as follows:Firstly,the main power topology adopts a phase shifted full bridge with clamping diodes,and the secondary side adopts a full bridge rectifier circuit.Based on the selected topology,the operating mode of the converter,the implementation strategy of Zero Voltage Switching(ZVS),and the mechanism of duty cycle loss are analyzed.The key device parameters,including the magnetic components and the localized selection of power devices,are designed in detail to improve the stability and safety of the modular power supply.Secondly,in order to effectively improve the dynamic performance of the module power supply,an average current control strategy is designed,and small signal modeling and controller design are carried out based on device parameters.This article designs an improved synchronous rectification control strategy that reduces the conduction loss of the body diode by compensating for dead time,thereby improving efficiency.Using a digital controller to control the power system,combined with the selection of a domestically produced Digital Signal Processor to complete algorithm development.Then,the main functional circuits of the module power supply are designed to ensure normal functionality while simplifying the circuit structure.Based on the designed topology parameters and control strategy,the corresponding simulation model is built,and the theoretical and design functions are verified.At the same time,a fully domestic brick module power supply prototype is designed.The prototype has a wide range of input from 225 V to 425 V and a wide range of output power of 2000W,and achieves a wide range of ZVS.The maximum working efficiency is 93.9%,which verifies the effectiveness of the control strategy and hardware design.