HIGH TURN DOWN RATIO DIRECT CONTROL FOR VARIABLE DISPLACEMENT PUMPS WITH FLOW SENSING

A system includes a variable displacement pump (VDP) (102) in fluid communication with an inlet line (104) and with an outlet line (106). A bypass valve (BPV) (110) includes a BPV inlet (112) in fluid communication with the outlet line, and a BPV outlet (114) in fluid communication with a bypass line that feeds into the inlet line upstream of the VDP. An actuator (118) is operatively connected to control the BPV to vary flow from the BPV inlet to the bypass line. A flow sensing valve (FSV) (148) is connected in the outlet line. The FSV includes a sensor configured to generate sensor data indicative of flow out of the outlet line. A controller (150) operatively connected to the actuator to control recirculation flow passed through the BPV based on the sensor data and based on a predetermined low threshold of flow through the VDP.