脉冲梯度磁场由梯度线圈产生，广泛用于磁共振成像设备的信号定位系统中。但该脉冲也会同时在线圈周围导体结构中感应出涡流场，从而导致总磁场改变，使图像出现变形或伪影，影响临床诊断。本文通过实验测量了 1.5 T 超导磁共振成像设备中脉冲梯度导致的涡流场；根据电感-电阻串联模型，分析了其数学模型，该模型表明涡流磁场可以由独立项和交叉项组成；然后本文定量测定了每项指数函数的振幅和时间常数等关键参数，为设计数字滤波器以进行预加重和波形整形提供了依据。本文涉及的测量是在设计的专用工装上进行，它由基于中心对称的六个方向上的水模和各自的射频接收线圈构成，通过加载测试序列可以得到有无涡流的原始一维数据，经计算可将其转化为有意义的采样数据。根据本文研究提及的数学模型，将采样数据用最小二乘法拟合后表明，数据符合电感-电阻串联模型，涡流效应确实存在。通过对比实验同时也进一步证实，用数字滤波器对脉冲进行预加重后，涡流场被有效减小。本文建立了系统函数的数学模型，验证了预加重在减小涡流上的实用价值，提出了改进办法，为磁共振设备减轻涡流效应提供了参考
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