大功率核磁共振找水仪发射机的设计  

Design of High-Power Nuclear Magnetic Resonance Instrument Transmitter

作　　者：李勇[1] 王国富[1] 高平东[1] 

机构地区：[1]桂林电子科技大学广西无线宽带通信与信号处理重点实验室,广西桂林541004

出　　处：《计算机测量与控制》2014年第1期166-167,171,共3页Computer Measurement &Control

基　　金：国家自然基金(61102115);广西研究生教育创新计划项目(YCSZ2013067)

摘　　要：文章介绍了一种基于LC串联谐振原理的大电流，高精度核磁共振找水仪发射机。该发射机利用AD9850产生探测点的拉莫尔频率，通过H桥电路产生大功率方波，经过线圈和谐配电容组成的谐振回路，转化为功率正弦激发脉冲，完成大电流的发射。实验结果表明：在额定条件下，发射机输出的频率精确控制在1500～3700Hz，交变电压最大值为4000V，精度稳定在±0．1％，电流最大值为450A，精度稳定在±0．5％；发射机具有输出功率大、探测距离深、集成度高以及智能化、便携安全等特点；具有很大的市场推广价值，该方案已经成功应用于实际的产品中。A high-- current, high-- precision pulsed current transmitter based on the LC series resonant principle is discussed. The transmitter adopts AD9850 to generate probe point Larmor frequency, by the H--bridge circuit to produce high--power square wave, and coil harmony with capacitance form a resonant circuit, and converted into power sinusoidal excitation pulses, completed current emissions. The experimental results showed that, at rated conditions, Precise control of the frequency of the transmitter output at 1500Hz;3700Hz, Alternating voltage max 4000V, accuracy and stability at 0.1%, Current maximum is 450A, stable at 0. 5% accuracy; The instrument lea tures many merits such as high output power, high integration, and intelligent, portable security. Has great marketing value, the program has been successfully applied to the actual products.

关 键 词：高精度 AD9850 拉莫尔频率 LC串联谐振 H桥电路 

分 类 号：TP302[自动化与计算机技术—计算机系统结构]