一、概述在所有的伺服系统中(包括电伺服、液压伺服、气动伺服、电液压伺服、气液压伺服等),电液伺服系统的质量最高,品质最好。原因是它集中了电气输入讯号和反馈讯号的灵活性、快速性和液压执行元件(液压马达、油缸)的小惯量的优点,使电液伺服系统能达到的精度和快速性为最高。特别是在大功率系统中,这个优点更为突出。电液伺服系统虽然具有上述无可比拟的优越性,但是在发展这种系统时碰到的一个困难是电和液压之间的转接元件——电液伺服阀是比较复杂的,从而限制了电液伺服系 I. Overview In all the servo system (including electric servo, hydraulic servo, pneumatic servo, electro-hydraulic servo, pneumatic servo, etc.), electro-hydraulic servo system of the highest quality, best quality. The reason is that it combines the flexibility of electrical input signals and feedback signals, fastness, and the small inertia of hydraulic actuators (hydraulic motors, cylinders) to maximize the accuracy and speed of electro-hydraulic servo systems. Especially in high-power systems, this advantage is even more prominent. Although the electro-hydraulic servo system has the above incomparable superiority, one difficulty encountered in developing such a system is that the electro-hydraulic servo valve, which is a transition element between the electric and hydraulic pressure, is relatively complicated, thus limiting Electro-hydraulic servo system