I want to use a proportional valve for controlling the pressure in a tank/cylinder. In our design we need to have two profiles for PC valve. The profiles have to be time based. One profile is to build the pressure from 0 bar to 50 bar in 2 Secs and another to drop the pressure from 50 bar to 0 bar in 2 Secs (see figure below). Profile is shown in attachment. The PC valve I am using is Reducing/Relieving valve. Does my design require a PID? Any help is appreciated....

The accuracy isn't that much stringent. I am a newbie in the field of hydraulics.
The valve I have chosen is, pressure reducing/relieving. My doubt is, whether I can achieve the requirement as per in graph using an Open loop method. Or should I go for a closed loop method (using PID/similar) since over the period the spring constant of valve may get changed and thus the pressure values as per current rating.

 

If you want those pressure steps for those milliseconds, I believe you will need a processor.

 

Normally a Hyd proportional valve requires some kind of PID control.
Max.