一种低噪声开关电源在光纤陀螺系统中的应用

摘要

在高精度光纤陀螺系统中,开关电源中的spike毛刺噪声会串扰光纤陀螺的信号处理电路,造成系统采样误差.本文分析了开关电源spike噪声的成因及其对光纤陀螺性能的影响机理,并在此基础上提出摆率控制是一种适用于光纤陀螺系统电源的低噪声电源技术.利用摆率控制技术,一种低噪声特性的开关电源模块被开发出来,并应用于光纤陀螺系统.该开关电源模块由DC-DC电路和LDO电路两部分组成,并在DC-DC电路中通过摆率控制电路实现其低噪声性能.完成后的低噪声电源模块能够在200 MHz的测试带宽下实现1 mV量级的峰峰值噪声水平.经过对比测试,采用低噪声电源的两支被测光纤陀螺分别表现出了3.1％和4.4％的噪声优化特性.%In high-precision fiber-optic gyroscope (FOG) system, the spike noise of DC-DC power source can lead to a considerable disturbance to the signal processing circuit of FOG, which results in a sampling error. In this work, the cause of spike noise and the influence mechanism were clarified. The slew rate control technology was researched and proved to be an effective solution to prevent spike noise of FOG power source. Using slew rate control technology, a kind of low-noise power module has been developed and applied successfully in the FOG system. This power module consists of DC-DC circuit and LDO circuit, and slew rate control circuit was used in the DC-DC circuit to realize low-noise performance. The peak-to-peak noise value of the developed power module was tested to be about 1 mV in a bandwidth of 200 MHz. Two typical FOG systems were tested with the use of this low-noise power source, and their output noise improvement were 3.1％ and 4.4％.