Research On Practicability Of A 1000W Full Brick Module Power Supply

With the development of industry and national defense, the requirement of the power level, voltage stage, efficiency, volume and weight of DC/DC module power supply are improved. At present, the market for high voltage and high power module power supply is monopolized by foreign products. Domestic researches on high voltage and high power module power supply start late, and the technology skills fall behind, which has bad effect to our country industry and national defense.In this paper, a wide input/high voltage, output 28V/1000W brick DC/DC module power supply is the mainly research object. The advantages and disadvantages of the commonly used DC/DC topology were detailed analyzed. Based on the actual requirements of the project, a transformer primary side series LLC+ output end in parallel buck cascaded DC/DC converter circuit topology is proposed. Compared with the traditional topology for high frequency and high voltage DC/DC converter, this topology has the following characteristics:1. Soft switching of high side switches in full voltage and full load range; 2. No duty cycle loss; 3. High precision of output voltage and fast dynamic response; 4. Operating with fixed frequency, and with minimum interference to external system; 5. Simple control strategy, and automatic current sharing when paralleling.According to the topology, this paper firstly introduces the working stages of it, and then introduces the design principles of this two stage circuit. Furthermore, a prototype is built to verify the actual operation of the topology.This research is a practical application research. Therefore, besides the main circuit, this paper also studied on the problems and key points during the practical engineering application. The experimental verification of the practical prototype is carried out in the end.