相控阵井壁成像仪高压电源纹波噪声抑制研究

针对超声相控阵井壁成像仪工作环境恶劣以及超声脉冲发射所需高压电源纹波噪声对超声回波信号干扰大的问题,提出一种高温环境下高压电源纹波噪声抑制方法并进行设计分析。本方法综合开关电源与线性稳压电源各自的技术优势且注重纹波噪声抑制和耐高温设计。利用开关电源完成不同电压幅值的高效转换并在电源输出端增设专门的EMI滤波电路,再利用屏蔽罩对电源进行屏蔽,最后输出电压再经过一级线性稳压电路进一步进行稳压滤波。实测结果表明,利用该方法,电源的纹波与辐射噪声得到了抑制,有效减少电源对回波信号的干扰,且输出电压稳定,提高了超声相控阵井壁成像仪井下工作的稳定性。

The high voltage power supply ripple and noise rejection of phased array imaging system

A basic method in the design of high voltage power supply ripple rejection of phased array imaging system was presented because of the adverse circumstances of the ultrasonic phased array borehole imaging work environment and the severe interference on ultrasonic echo signal caused by high power supply. In this method, the technical advantages of switched-mode power supply and linear regulated power supply were combined and the ripple noise reduction and high temperature design were focused on. To suppress the ripple and noise, a specialized EMI filter circuit and a screening can was designed to the power source. Furthermore a linear regulated voltage circuit was added to the output port as well to obtain a better effect. From the results obtained so far, it showed that the ripple and noise were suppressed well and the interference from the high power supply to the ultrasonic echo was restrained effectively with the help of the approach,which improved the stability of the system working underground.