Abstract: An electric submersible pump includes a plurality of centrifugal pump stages, each stage including a rotating impeller and a stationary diffuser mounted on a shaft coupled to a motor. An upthrust washer can be disposed axially between an impeller and its associated diffuser at or near a tip of the impeller, and the gap between the impeller tip and diffuser can define the end play or axial clearance for the pump. If the upthrust washer wears away, upthrust rubbing occurs at the impeller tip instead of proximate the pump shaft to advantageously help protect the shaft from damage or failure related to heat. In some ESPs, an upthrust bearing assembly can be located at the pump head. A downthrust washer can be disposed in an upstream facing groove of the impeller. The downthrust washer can have a thickness greater than 0.10 in.

Abstract: The invention provides an integral high-voltage capacitor assembly that yields very low self inductance and provides voltage and current multiplication. The capacitor assembly has two or four capacitors connected in series, with each capacitor made up of a stack of capacitor cells (40) also connected in series. Each of the capacitor cells (40) includes an arrangement of a pair of elongate foil electrodes (10) separated by dielectric (20, 30), and multiply-folded in a substantially flat, wound configuration. In the case of the two-capacitor assembly, in one embodiment the adjacent capacitor cells of the first capacitor (11) are connected in series by joining their foil electrodes on only one longitudinal side of the foil electrodes, while the adjacent capacitor cells of the second capacitor (12) are connected in series by joining their foil electrodes on both longitudinal sides of the foil electrodes.

Abstract: The invention provides an integral high-voltage capacitor assembly that yields very low self inductance and provides voltage and current multiplication. The capacitor assembly has two or four capacitors connected in series, with each capacitor made up of a stack of capacitor cells (40) also connected in series. Each of the capacitor cells (40) includes an arrangement of a pair of elongate foil electrodes (10) separated by dielectric (20, 30), and multiply-folded in a substantially flat, wound configuration. In the case of the two-capacitor assembly, in one embodiment the adjacent capacitor cells of the first capacitor (11) are connected in series by joining their foil electrodes on only one longitudinal side of the foil electrodes, while the adjacent capacitor cells of the second capacitor (12) are connected in series by joining their foil electrodes on both longitudinal sides of the foil electrodes.