中文摘要：

介绍了三级电反馈伺服阀的结构原理和相应计算机辅助测试系统，并对测试系统输出控制信号进行了实时采样和频谱分析，找出了干扰信号的频率和强度分布，设计了相应的π形低通滤波器对测试信号进行净化，效果较好。

英文摘要：

Introduced the structure principle and the computer assistance test system of three stage servovalve with electrical position feedback, and carry out real time sampling and frequency analysis to the output control signals of the test system. Have found out the frequency and strength distribution of the interference signals, and have designed corresponding π shape low clear wave filter to purify the test signals, and the effect is evry good.