CONTROL OF PRESSURE CONTROLLER AT BOUNDARY VALUES Russian patent published in 2019 - IPC G05D16/20 

FIELD: control systems.

SUBSTANCE: flow network (1) comprises pressure control means (10) configured to adjust the fluid pressure drop between two positions in flow network (1) according to the pressure setting, and controller (6) configured to correct pressure setting and monitor physical quantity value in system. Operation of controller (6) is carried out in normal load mode, in which pressure control means (10) are set to basic setting (20) of pressure when physical value is within range of first threshold (21, 27), and in unstable load control mode, which includes change of pressure set point to unstable load setting (25, 28), when physical value becomes lower than first threshold (21, 27). Controller (6) switches from the unstable load mode to the normal load when the physical value becomes higher than second threshold (26, 29), wherein the value of second threshold (26, 29) is higher than the value of the first threshold value (21, 27).

EFFECT: improving efficiency of system control even at flow rates, at which control valve connected to flow system operates under conditions influencing entire operation of flow system, for example, when valve is almost closed.

9 cl, 3 dwg