【作者】 张晶；

【导师】 李杏华；

【作者基本信息】 天津大学 ， 仪器科学与技术， 2014， 硕士

【摘要】 相控阵超声扫描检测是近年来兴起的超声检测技术，是按照一定规律排布超声阵列换能器，通过控制激发晶片的个数和激发时序，来控制超声波声束扫描聚焦的范围和位置。相控阵超声无损检测技术因其快速灵活而高效的声束扫查聚焦控制、较大的动态变化范围以及清晰的实时成像，逐渐发展为一种主流的工业无损检测新兴技术手段，在石油长途运输管道及大型储罐焊缝检测中起到不可替代的作用。国内自主研制的超声相控阵检测系统在相关技术层面还有很大的发展空间。本论文设计了一个应用于大型石油储罐焊缝检测的多通道超声相控阵自动检测系统，并就其中几项重点技术进行了仔细研究。本文主要工作内容如下：1.对超声相控阵检测的原理进行了综合描述，详细讨论了超声相控阵动态扫描的聚焦法则和延时控制法则及其物理依据，作为本课题的理论依据。2.设计了32通道超声相控阵自动检测系统的硬件方案，主要是针对16通道仪器硬件的缺陷，在此基础上进行了重要模块电路的改进和重新设计。包括对相控阵超声脉冲发射电路、回波信号接收电路、超声模拟前端集成电路、DDR存储部分电路、两片FPGA作为主从控制器的接口电路等重要电路模块的改进设计。3.设计了基于乒乓存储的高速实时数据通讯系统设计方案，给出高速数据通讯系统的整体架构的同时，就USB2.0控制器基于Slave FIFO模式的数据读写控制，DDR存储芯片的读写操作控制时序以及使用IP核对DDR接口控制等方面进行了深入研究。并通过大量仿真和实验验证，证明了数据通讯系统的可行性。4.设计了使用DSP Builder实现对超声回波信号的滤波的方案，并通过仿真实验验证了对回波信号滤波的效果。本文设计的多通道相控阵检测系统已投入应用于中石油大型储罐焊缝检测中，目前处在试验阶段。系统的稳定性、高效性和实时性基本满足工业超声无损检测的各项指标。更多还原

【Abstract】 Ultrasonic phased array detection is an emerging technology of ultrasonicdetection technology in recent years. It can control the extent and location of theultrasonic beam scanning focus on by arranging the ultrasonic transducers accordingto a certain rule. Phased array ultrasonic NDT technique is becoming one of themainstream industrial NDT techniques because of its fast, flexible and efficientscanning beam focus control method, large dynamic range of the beam scanning andits real-time clear imaging. It has played an irreplaceable role in weld inspection of oilpipelines and large tanks in long-distance transportation. However, a lot of works stillneed to be done in the application of ultrasonic phased array inspection technology inchina. The design in this paper is a multi-channel ultrasonic phased array system thatcan automatically detect weld defects of large oil storage tanks. The main contents ofthis paper are as follows:1. The method in this paper gives a comprehensive description of the principle ofultrasonic phased array inspection. The focus law of ultrasound phased array scanningwas discussed as the theoretical foundation of this paper.2. A design of a32-channel ultrasonic phased array automatic detection systemhardware solutions is shown in this paper, including the ultrasonic pulses transmittingcircuit, the echo signals receiving circuit, the receiving channel selection module,etal. The design also gives the hardware system proposal associated with high-speedreal-time data communication system, including the configuration of double FPGAs,the overall power management and clock management, DDR memory circuitdesign,et al.3. The real-time storage and retrieval of data with high-speed and large-capacityis a technical problem in ultrasonic phased array nondestructive detection. To solvethis problem, FPGA was used in this paper as the main controller and two DDRSDRAM was used to achieve ping-pong storage by sharing the same PLL and DLL ina FPGA. Results obtained from system simulation and test showed that the designedsystem can be operated stably to store and transit16-bit parallel digital echo signalsampled by a125MSPS AD sampler without dead time. The real-time wave imageshowed in host computer proves that the data sent from FPGA is continuous. 4. The design gives a scheme of ultrasonic echo signal filtering by using DSPBuilder. The real-time wave image displayed in host computer shows the satisfactoryresults of filtering.The design in this paper has been applied in large oil storage tank weld inspectionrecently. It is currently in the testing stage. The stability and efficiency of this systemmeets the industrial ultrasonic nondestructive testing standards well.更多还原