SURFACE MOTOR DIRECT-DRIVE SUCKER-ROD SCREW PUMP DEVICE

• US 20140197767A1
• Filed: 03/07/2014
• Published: 07/17/2014
• Est. Priority Date: 08/04/2006
• Status: Active Grant

• Current Assignee: Millennium Oilflow Systems & Technology Inc.
• Original Assignee: Millennium Oilflow Systems & Technology Inc.
• Inventors: Liu, Jun, Gou, Songbo, Tang, Youngjian, Cong, Hengli
• Granted Patent: US 9,059,606 B2
• Time in Patent Office: Days
• US Class Current: 318/400.38
• CPC Class Codes: E21B 43/126 Adaptations of down-hole pump systems powered by drives outside the borehole, e.g. by a rotary or oscillating drive powered by fluid E21B43/129
• CPC Class Codes: F04B 47/02 the driving mechanisms being situated at ground level F04B47/12 takes precedence
• CPC Class Codes: F04C 14/08 characterised by varying the rotational speed
• CPC Class Codes: F04C 15/008 Prime movers
• CPC Class Codes: F04C 2/1071 the inner and outer member having a different number of threads and one of the two being made of elastic materials, e.g. Moineau type
• CPC Class Codes: H02K 29/00 Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
• CPC Class Codes: H02K 7/003 Couplings; Details of shafts means for mounting rotors on shafts H02K1/28
• CPC Class Codes: H02P 25/026 thereby detecting the rotor position
• CPC Class Codes: H02P 25/03 with brushless excitation
• CPC Class Codes: H02P 6/14 Electronic commutators
• CPC Class Codes: H02P 6/16 Circuit arrangements for detecting position
• CPC Class Codes: H02P 6/28 Arrangements for controlling current H02P6/10 takes precedence
• CPC Class Codes: Y10T 74/18576 including screw and nut
• CPC Class Codes: Y10T 74/18664 Shaft moves through rotary drive means

Abstract

A surface motor direct-drive sucker-rod screw pump device is driven by a vertical three-phase permanent magnet brush-less DC motor, and comprises a motor controller (6), a rectifying circuit, an inversion circuit, a CPU and a driving circuit. The motor controller (6) is used to adjust the voltage and frequency of the motor by the rectifying circuit, the inversion circuit, the CPU and the driving circuit. Thus, the speed of the motor can vary from zero to the maximum. The device is easy to operate and has a higher efficiency.

Claims

1. A direct drive motor for driving a polished rod connected to a screw pump in a well, the direct drive motor comprising:

an electric motor with a hollow shaft, the hollow shaft being sized to receive the polished rod; and

a clamp for clamping the polished rod and supporting the polished rod within the hollow shaft.

2. The direct drive motor of claim 1, further comprising a motor controller.

3. The direct drive motor of claim 2, wherein the motor controller comprises a rectification circuit for rectifying a three phase alternating current into direct current.

4. The direct drive motor of claim 3, wherein the motor controller comprises a converter circuit for converting the direct current into alternating current which can be adjusted.

5. The direct drive motor of claim 4, wherein the motor controller comprises one or more sensors for speed measurement and feedback.

6. The direct drive motor of claim 2, wherein the motor controller comprises open loop control.

7. The direct drive motor of claim 5, wherein the motor controller comprises closed loop control.

8. The direct drive motor of claim 4, wherein the motor controller comprises a Hall position sensor for detecting the rotary position of a rotor of the electric motor.

9. The direct drive motor of claim 8, wherein the motor controller comprises a CPU for modulating the direct current brushless sine wave of a mono-chip microcomputer with the Hall sensor.

10. The direct drive motor of claim 4, wherein the motor controller comprises a driving circuit for isolating the signal and magnifying the power, as well as acting on the converter circuit and adjusting the voltage and frequency of the electric motor to provide continuous speed adjustment.

11. The direct drive motor of claim 3, wherein the rectification circuit is a three phase semi-control bridge, the converter circuit is a three phase full-bridge converter output employing an insulated gate bipolar transistor, and the CPU has inputs of controller direct current bus voltage, motor current and temperature signal of a module radiator.

12. The direct drive motor of claim 4, wherein the voltage of the three phase alternating current supplied to the motor controller is between 3×

380V and 3×

690V at a frequency of between 50 and 60 Hz.

13. The direct drive motor of claim 9, wherein a current sampling signal between the converter circuit and the motor is transferred into the CPU.

14. The direct drive motor of claim 9, wherein the CPU board has a communication interface and a human-machine operation panel.

15. The direct drive motor of claim 9, wherein the CPU has a start-stop signal input port.

16. The direct drive motor of claim 1, wherein the electric motor is a vertical three phase permanent magnet brushless direct current motor.