Patent ID: 8037936
Filing Date: 2011-10-18
Classification: E21B,F04D

Abstract:
1. A method of pumping well fluid, comprising: providing an electrical submersible pump (ESP) system, the ESP system having a pump and a pump motor coupled to the pump by a seal/equalizer section that reduces a pressure differential between lubricant in the motor and fluid in the borehole, the pump motor having power selectively delivered at a normal operating voltage, a normal waveform, and a normal frequency, and an electrical power supply in communication with the pump motor; providing the ESP with a heat transfer system including a lower portion proximate the pump motor, an upper portion proximate the pump, tubes extending alongside the seal/equalizer section between the upper and lower portions, and a working fluid within the lower portion, the upper portion and the tubes; immersing the ESP in the well fluid; supplying a voltage to the pump motor from the electrical power supply that is less than the normal operating voltage to inductively generate heat energy with the pump motor; and transferring heat energy generated by the pump motor to the working fluid in the lower portion of the heat transfer system, causing the working fluid to vaporize and flow to the upper portion via one of the tubes, thereby transferring heat to the pump and surrounding well fluid and causing the working fluid in the upper portion to condense and return to the lower portion via the other of the tubes.