Common Mode Filter
The US Department of Energy (US DOE) provides very specific guidelines to reduce the damaging effects of these high frequency abnormalities on unfiltered PWM VFDs (e.g. using inverter duty sized motors, limiting the cable length to less than 15 feet and using bearing insulation).
All these recommendations are very possible for surface systems, however can be immediately discounted for downhole ESP systems. The only solution for such applications is to mitigate those high frequency components and common mode currents on the surface.
Magney Grande have announced the market release of The Guardian line of Common Mode Filters (CMFs). The CMF is a patent-pending, field tested/proven, standalone component to extend overall run times by reducing or eliminating high frequency induced failures.
High frequency noise on an ESP system operating with a VFD can cause a host of Power Quality (PQ) related anomalies, including nuisance tripping of a VFD, instantaneous overcurrent, zero crossing faults and erratic data transfer.
High frequency currents cause skin effect heating and high frequency voltages cause reflection. The smallest and weakest links in the system are most susceptible to premature failures (e.g. penetrators, cable (where no mechanical damage is present), splices (not due to workmanship), MLE/Pothead, motor windings, and bearings).
Contact MAGNEY GRANDE for more information on Common Mode Filters (CMFs) for your PWM VFD applications.