Patent ID: 7798215
Filing Date: 2010-09-21
Classification: E21B,F04D

Abstract:
1. A method of breaking a gas lock in an electrical submersible pump assembly, the method comprising: (a) detecting an occurrence of gas lock in a electrical submersible pump assembly, the electrical submersible pump assembly comprising an electrical submersible pump located in a well bore, a pump motor located in the well bore and attached to the electrical submersible pump, and a motor controller located at the surface of the well bore and electrically coupled to the pump motor through a three-phase power cable, by the substeps of: (b) breaking the detected occurrence of gas lock by the substeps of: wherein the generated threshold value based on historical data of values associated with the pump motor of the electrical submersible pump assembly is between 65% and 75% of a peak instantaneous value measured over a predetermined period of between 2 and 5 minutes; wherein the first predetermined duration defining the waiting period is between 3 and 15 minutes; wherein the second predetermined duration defining the flush period is between 10 and 15 seconds; and wherein the predetermined value defining the flush value is between 20 and 25 Hz.