IP Library Granted Patent US 12,503,923
Granted Patent B2
US 12,503,923 · App. 18/585,425 · Granted Dec 23, 2025

Variable frequency drive configuration for electric driven hydraulic fracking system

Inventors: John Fischer (Hempstead, TX); John J. Crosetto (Oak Forest, IL); David Kubricht (Cypress, TX); Richard Cheatham (Houston, TX); Jeffrey Pollack (Joliet, IL); Chad Lawman (Joliet, IL); David Todd (Houston, TX); Tyler Nolen (Houston, TX)
Assignee: Halliburton Energy Services, Inc.
E21B21/08E21B4/04E21B7/022E21B43/2605E21B43/2607F04B17/03F04B17/06F04D13/0686H02B1/52H02B5/00H02J13/00036H02K7/18H02P27/04E21B4/02F05B2220/706F05B2240/941
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Quick Facts
Patent No.
US 12,503,923
App. No.
18/585,425
Granted
Dec 23, 2025
Kind
B2
Abstract

An electric driven hydraulic fracking system is disclosed. A pump configuration that includes the single VFD, the single shaft electric motor, and the single hydraulic pump that is mounted on the single pump trailer. A pump configuration includes a single VFD configuration, the single shaft electric motor, and the single shaft hydraulic pump mounted on the single pump trailer. The single VFD configuration converts the electric power at the power generation voltage level distributed from the power distribution trailer to a VFD voltage level and drives the single shaft electric motor to control the operation of the single shaft electric motor and the single hydraulic pump. The VFD voltage level is a voltage level that is required to drive the single shaft electric motor. The VFD configuration also controls operation of the auxiliary systems based on the electric power at the auxiliary voltage level.

Claims (42)

1 . A variable frequency drive (VFD) for hydraulic fracturing, comprising:

cells;

capacitors associated with the cells;

a transformer configured to pre-charge the cells;

a relay electrically coupled to the transformer; and

a controller configured to, in response to determining that the capacitors are pre-charged to a threshold voltage level, control the relay to transition from an open state to a closed state to enable the transformer to provide electric power to the cells at a first voltage level,

wherein upon being provided with the power at the first voltage level from the transformer, the cells are configured to provide electric power to an electric motor at a second voltage level to control the electric motor to drive a hydraulic pump to pump fracking fluid into a well, and

wherein the first voltage level is higher than the second voltage level.

2 . The VFD of claim 1 , wherein the transformer is further configured to provide electric power at a third voltage level to the capacitors to pre-charge the capacitors.

3 . The VFD of claim 1 , wherein pre-charging the capacitors prevents or mitigates a propagation of in-rush current back to a power generation system.

4 . The VFD of claim 1 , wherein the first voltage level is a power generation voltage level.

5 . The VFD of claim 1 , wherein the first voltage level is in a range of 4160 V to 38 kV.

6 . The VFD of claim 1 , wherein the second voltage level is a VFD voltage level.

7 . The VFD of claim 1 , wherein the second voltage level is 4160 V.

8 . The VFD of claim 1 , wherein the second voltage level is customizable.

9 . The VFD of claim 1 , wherein the transformer and the cells are disposed on a trailer.

10 . The VFD of claim 2 , wherein the first voltage level is higher than the third voltage level.

11 . The VFD of claim 3 , wherein the power generation system is configured to provide electric power at the first voltage level to the transformer.

12 . The VFD of claim 10 , wherein the transformer is provided with electric power at the third voltage level to pre-magnetize the transformer.

13 . The VFD of claim 10 , wherein the third voltage level is an auxiliary voltage level.

14 . The VFD of claim 10 , wherein the third voltage level is 480 V.

15 . The VFD of claim 12 , wherein pre-magnetizing the transformer prevents or mitigates a propagation of in-rush current back to a power generation system.

16 . The VFD of claim 12 , wherein the controller is further configured to, in response to determining that the capacitors are pre-charged to the threshold voltage level and the transformer is pre-magnetized to a pre-magnetization threshold, control the relay to transition from the open state to the closed state to enable the transformer to provide the electric power to the cells at the first voltage level.

17 . A variable frequency drive (VFD) for hydraulic fracturing, comprising:

a transformer;

cells electrically coupled to the transformer and configured to provide electric power to an electric motor to control the electric motor to drive a hydraulic pump to pump fracking fluid into a well;

contactors respectively associated with the cells; and

a controller configured to control a contactor, of the contactors, to transition from an open state to a closed state, in response to detecting that a cell, of the cells, associated with the contactor, is not operating at full capacity.

18 . A variable frequency drive (VFD) for hydraulic fracturing, comprising:

a transformer configured to receive electric power at a first voltage level, phase shift the electric power at the first voltage level, and output the phase shifted electric power at the first voltage level; and

cells each configured to receive the phase shifted electric power at the first voltage level from the transformer, and output electric power as a partition at a second voltage level,

wherein the partitions are connected provide electric power at a third voltage level to an electric motor to control the electric motor to drive a hydraulic pump to pump fracking fluid into a well, and

wherein the third voltage level is higher than the second voltage level and lower than the first voltage level.

19 . A method for hydraulic fracturing, comprising:

receiving, by a transformer, electric power;

phase shifting, by the transformer, the electric power;

outputting, by the transformer, the phase shifted electric power at a first voltage level;

receiving, by cells, the phase shifted electric power at the first voltage level from the transformer;

outputting, by each of the cells, electric power as a partition at a second voltage level; and

connecting the partitions to provide electric power at a third voltage level to an electric motor to control the electric motor to drive a hydraulic pump to pump fracking fluid into a well,

wherein the third voltage level is higher than the second voltage level.

20 . The method of claim 19 , wherein the third voltage level is lower than the first voltage level.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 23, 2024
From: FISCHER, JOHN; CROSETTO, JOHN J.; KUBRICHT, DAVID; CHEATHAM, RICHARD; POLLACK, JEFFREY; LAWMAN, CHAD; TODD, DAVID; NOLEN, TYLER
To: NATIONAL SERVICE ALLIANCE HOUSTON, LLC
Reel/Frame 066542/0701 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 23, 2024
From: NATIONAL SERVICE ALLIANCE HOUSTON, LLC
To: HALLIBURTON ENERGY SERVICES, INC.
Reel/Frame 066543/0234 →
Continuity (11)
Continuation 18370245 · Sep 19, 2023
Continuation 18204062 · May 31, 2023
Continuation 17982701 · Nov 8, 2022
Continuation 17735759 · May 3, 2022
Continuation 17480809 · Sep 21, 2021
Continuation 17226953 · Apr 9, 2021
Continuation 17134860 · Dec 28, 2020
Continuation 16943719 · Jul 30, 2020
Continuation 16790581 · Feb 13, 2020
Provisional Application 62805521 · Feb 14, 2019
Related Publication 20250198246A1 · Jun 19, 2025
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