大功率红外激光器高效驱动电源设计

根据大功率红外激光器功率-电压-电流(Power-Voltage-Intensity of current,PVI)曲线的特点,提出一种双环控制结构的恒流驱动电源设计方案。硬件电流控制环路采用深度电流负反馈电路实现了高精度恒流驱动;数字式控制环路根据激光器工作电流实时调节DCDC输出电压,使得恒流电路中MOSFET稳态压降保持恒定,从而在保证电流控制精度的同时显著提升了系统效率。本文首先分析了激光器PVI曲线的特点,提出了系统总体设计思路,然后重点阐述了输出可调的DCDC电源模块和硬件恒流驱动电路的设计方法,并详细介绍通讯软件和DCDC电压控制算法的实现过程,最后给出了DCDC电源效率和电流控制的测试结果,通过与传统方案的对比测试验证了本设计在系统效率上的优势。

Design of efficient power supply for high power infrared laser diode

According to the Power-Voltage-Intensity of current(PVI) characteristic of high power infrared laser diode,one constant-current power scheme with two control loops is proposed.The hardware-based control loop performs high-precision current regulation;the software-based digital control loop is used to adjust the DCDC module output voltage according to the laser′s working current,and thus maintains the steady-state voltage drop of MOSFET in constant-current circuit almost constant.This type of structure effectively reduces the power consumption,and meanwhile holds high current accuracy.Firstly,the PVI characteristic is analyzed and the system structure is proposed.Then the design principle of the constant-current driver circuit and high-efficiency DCDC power supply circuit with adjustable output voltage are designed.The implement of communication protocol and the control algorithm of DCDC output voltage are discussed in detail.Finally,DCDC efficiency and laser current control effect are given,and the comparison test result further reveals the efficiency advantage of the proposed design scheme.