能馈式电子负载中交错并联Boost电路的设计

Design of interleaved Boost converter in energy-feedback electronic power load

为满足服务器电源测试用能馈式电子负载对第一级DC/DC低压大电流输入、低输入电流纹波和高效率的要求,第一级DC/DC采用交错并联Boost电路。分析了该电路的工作原理,给出了电路中各主要元器件的选取原则。针对电子负载恒流输入需求,给出了基于dsPIC33FJ16GS504的输入电流恒流控制环路设计思路和方法。利用DSP实现了快速运算,达到精确设定输入电流大小的目的。最后,制作了一台12 V/100 A输入,48 V输出的1.2 kW实验样机。实验结果验证了该电路在低压大电流输入情况下的可行性,电路工作稳定,满足了能馈式电子负载的要求。

In order to satisfy the requirements of low voltage and large current, low input current ripple, and high efficiency in energy-feedback electronic load for server power supply test, an interleaved Boost converter was employed in first stage DC/DC. The operation principle of the circuit was analyzed and the selecting method of main components was presented. In accordance with the demand of constant input current in electronic load, design of constant current control loop based on dsPIC33FJ16GS504 was introduced. Accurate set of input current was achieved by means of high-speed calculation with DSP. Finally a 1.2 kW prototype was built with input 12 V/100 A and output 48 V. The results validate the feasibility of the proposed converter with input of low-voltage and large-current, show that the circuit can work in stable state and meet the requirements of energy feedback electronic load system.