| 摘要 |
A pump controller for electrical connection between a source of chemical supply and a DC powered chemical injection pump of the type having a reciprocating piston or diaphragm for delivering a quantity of chemical to a well head after each compression stroke of the pump, the controller including: a switch operable to sequentially deliver activation current to the pump; a voltage sensor between the pump and the switch to extract DC voltage signals indicative of activation of the pump, an analogue-to-digital convertor for converting the sensed DC voltage signals into digital format; a digital signal processor operative to differentiate DC stroke voltage signals from the sensed voltage signals, thereby to indicate the occurrence of each stroke; and a switch controller programmed with pump parameters and target chemical delivery dosages to sequentially deliver activation current to the pump, measured or calculated from the digital DC stroke voltage signals, and hence chemical delivery to the well via the injection pump at required intervals. |
