A large-flow-rate electro-hydraulic control valve was designed by adopting pressure difference feedback rather than displacement feedback,the results of which was cost savings. Elliptical oil ports were designed to reduce the length and mass of the spool to improve the system response speed. For the fact that the response speed of hydraulic valve is affected by the throttling window,a system requiring large flow rate usually adopts large throttling window while a system requiring small flow rate usually ado...