The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 26, 2026
Filed:
Oct. 05, 2024
Weatherford Technology Holdings, Llc, Houston, TX (US);
Benson Thomas, Pearland, TX (US);
Mohammed S. Arefeen, Houston, TX (US);
Weatherford Technology Holdings, LLC, Houston, TX (US);
Abstract
A variable frequency drive to drive an electric motor for a reciprocating pumping unit includes a rectifier, a filter, an inverter, and a capacitor bank. The rectifier converts AC power to DC power for filtering by the filter. The inverter converts the DC power to three-phase AC power for output to the electric motor. The capacitor bank has one or more capacitors connected to the DC bus. The capacitor bank can store regenerative power passed from the motor through the inverter and can supply the stored DC power to the DC bus to drive the electric motor. Control circuitry can control the speed of the electric motor provided by the variable frequency drive during strokes of the pumping unit. The control circuitry can pre-charge the capacitor bank from AC power. The control circuitry can detect any fault condition.