Patent ID: 11913444
Assignee: SENSIA LLC
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  E  H | IPC E  F  H

Claim 7:
8. A method for controlling an electrical submersible pump (ESP), comprising:
generating an electrical drive signal to power the ESP;
measuring a current of the electrical drive signal;
measuring a voltage of the electrical drive signal;
calculating a speed of a shaft of an electric motor of the ESP based on a frequency induced by rotation of the electric motor detected in the current;
calculating a density of a fluid in the ESP based on the speed;
determining a torque in the ESP based on a measured current of the electrical signal, a measured voltage of the electrical signal, a resistance of a conductor that electrically couples the ESP to drive circuitry, and
a resistance of a stator of the ESP; and
reducing the speed of the electric motor responsive to the density being lower than a predetermined threshold value.