Intake monitoring for accurate proportioning

摘要

A fluid supply system configured for metering two or more fluids in controlled proportions, including a plurality of solvent supply lines, a pumping unit configured for taking in fluids from selected solvent supply lines and for supplying a pressurized mixture, a proportioning valve configured for modulating solvent composition by sequentially coupling selected ones of the solvent supply lines with the inlet of the pumping unit, a sensor configured for sensing process information in the fluid supply system, an analysis entity configured for analyzing the process information for determining reciprocating element related information at a beginning of fluid intake, and a control unit configured for switching the proportioning valve to sequentially couple selected ones of the solvent supply lines to the inlet of the pumping unit at one or more switching points based on the given metering scheme and based on the reciprocating element related information.

主权项

1. A fluid supply system configured for metering two or more fluids in controlled proportions in accordance with a given metering scheme and for supplying a resultant mixture, the fluid supply system comprising:
a plurality of solvent supply lines, each fluidically connected with a fluid source providing a respective fluid; a pumping unit comprising an inlet, an outlet, and a reciprocating element configured for intaking fluid supplied at the inlet and for supplying the pressurized fluid at the outlet, wherein the pumping unit is configured for taking in fluids from selected solvent supply lines and for supplying a pressurized mixture of the fluids at the outlet; a proportioning valve interposed between the solvent supply lines and the inlet, the proportioning valve configured for modulating solvent composition by sequentially coupling selected ones of the solvent supply lines with the inlet; a sensor configured for sensing process information in the fluid supply system relating to a fluid intake process of the pumping unit; an analysis entity configured for analyzing the sensed process information and for determining as a result of the analysis, independently of a position of the reciprocating element within the pumping unit, the event of the beginning of a fluid intake process, wherein the analysis entity is further configured for determining reciprocating element related information at the event of the beginning of the fluid intake process; and a control unit configured for switching the proportioning valve to sequentially couple selected ones of the solvent supply lines to the inlet of the pumping unit at one or more switching points during a duty cycle of the reciprocating element coordinated with the motion of the reciprocating element based on the given metering scheme and based on the reciprocating element related information, wherein the control unit is configured for coordinating operation of the pumping unit and the proportioning valve for at least partially compensating for a discrepancy between an actual relationship between operation of the pumping unit and the proportioning valve, as indicated by the reciprocating element related information determined by the analysis entity, and a target relationship between operation of the pumping unit and the proportioning valve, as predefined for operating the fluid supply system.