Abstract
With the emergence of permanent magnet motors (PMM) in the ESP industry, new challenges have arisen regarding the potential for electrical energy generation during installation, operation, and pulling of the equipment. Among these challenges include how to properly terminate the ESP power cable conductors at the cable ends or point of work. Safety being of the highest importance, robust methods for terminating the conductors during each of these processes are necessary to prevent field electrical incidents.
Numerous opinions have been expressed and methods developed across the industry on how best to perform cable terminations, many of which are not compatible with each other. The industry's lack of agreement on when to apply each method and understanding on best practices has significant potential for serious field personnel safety incidents. This underscores the need for establishing the most robust methods considering the wide variety of potential scenarios that could be encountered.
This paper will evaluate six cable termination approaches through physical motor testing. A PMM with conductors connected to a long ESP cable reel will be forced to rotate at various speeds. The motor terminals and cable termination will be instrumented to measure both phase-to-phase and phase-to-ground voltage as well as current. Each approach will consider both ideal conditions and suboptimal conditions that may occur from downhole insulation damage. More than 100 permutations of these possible situations will be compared and evaluated. Recommendations will be made based on these results on when each termination method might be a valid and safe option including rankings to show which methods safely cover the broadest set of situations.
The results of this method comparison will provide actionable data such that the safest cable termination methods can be chosen. This will also guide field personnel on which methods should be avoided. Ultimately, this will contribute to establishing best practice throughout the ESP industry for conductor handling when PMM ESP systems are involved.
