Off-setting rate of pressure rise in a fluid system

A control arrangement for offsetting the rate of pressure rise within a fluid conduit network of a fluid system having a source of pressurized fluid, a reservoir, a fluid actuator, an electrically actuated control valve mechanism connected to the source of pressurized fluid, the reservoir and the fluid actuator, the fluid conduit network of the system having a predetermined maximum operating pressure level, the control arrangement comprising:

• an input controller connected to the electrically actuated control valve mechanism and operative to generate an electrical signal representative of the desired input;
• an electronic controller operative to receive the signal from the input controller and direct an output signal therefrom to the electrically actuated control valve mechanism;
• a pressure sensor arrangement operative to sense the pressures within the conduit network of the fluid system and deliver a signal representative thereof to the electronic controller;
• a control scheme operative in response to the sensed pressure signals to anticipate a pressure level that would exceed the predetermined maximum pressure level and direct an electrical signal to the electrically actuated control valve mechanism to bypass a portion of the fluid flow in the system to the reservoir to relieve the overpressure condition;
• and
• a low flow pressure relief valve disposed between the conduit network and the reservoir and operative in response to the pressure level in the conduit network exceeding the predetermined maximum pressure level to bypass a small volume of pressurized fluid to trim the level of any over-pressure condition.