Experimental Study on the Thermal Response of Electric Submersible Pump Motors to Load Variation Using Raman Distributed Temperature Sensing

This letter proposes a fiber-optic-based method for monitoring the temperature of stator windings and housing regions in electric submersible pump (ESP) motors using Raman distributed temperature sensing (RDTS). The experimental setup replicates conditions of downhole installations or subsea skids by enclosing the ESP within an unplasticized polyvinyl chloride pipe, with annular flow established between the motor housing and the inner wall of the pipe. Flow rate and electric parameters are continuously monitored to evaluate their relationship with motor temperature. The results indicate that RDTS can be an intrinsically safe solution for temperature monitoring in ESP-lifted wells for oil and gas production, where conventional electric-based sensors are often unsuitable due to limited installation space, harsh environment, high electromagnetic interference, and long distance between the ESP motor and platform.