DOWNHOLE ELECTRICALLY-DRIVEN ROTARY PUMP UNIT PROTECTION Russian patent published in 2016 - IPC G01N9/26 

FIELD: engines and pumps.

SUBSTANCE: claimed process consists in interruption of pump motor supply at the depth telemetry transducer reading equal to or lower than the preset magnitude. One pressure transducer is fitted at the pump intake while the second pressure transducer is arranged in tube space at the wellhead. Transducer pressure P_min whereat and below which the pump motor operation is interrupted and it is continuously calculated as the sum of two pressures, i.e. liquid column pressure P_hydro above the transducer and gas pressure above the gas-fluid interface (dynamic level) P_GFI: P_min = P_hydro+P_GFI. Note here that P_GFI is defined by calculation proceeding from the readings of the second wellhead pressure transducer while P_hydro is set constant proceeding from the in-well conditions and downhole pump performances.

EFFECT: higher efficiency of protection.

1 dwg, 1 tbl