Methods and systems for monitoring a fluid lifting device
First Claim
1. A system, comprising:
- a fluid lifting device located inside a well and comprising an electrical motor;
a three phase cable for coupling the fluid lifting device to a power source;
at least one high sensitivity differential current transformer for generating imbalance signals representative of an imbalance current in at least one of the electrical motor and the three phase cable, wherein the at least one high sensitivity differential current transformer is disposed such that the at least one high sensitivity differential current transformer surrounds at least a portion of the three phase cable; and
a processing subsystem for monitoring health of at least one of the fluid lifting device and the three phase cable based on the imbalance signals,wherein the imbalance signals comprise first imbalance signals representative of the imbalance current in the electrical motor, and second imbalance signals representative of a total imbalance current in the electrical motor and the three phase cable.
2 Assignments
0 Petitions
Accused Products
Abstract
A system (100, 200) is presented. The system includes a fluid lifting device (102, 202) located inside a well (106, 206), and comprising an electrical motor (108, 208), a three phase cable (114, 214) for coupling the fluid lifting device to a power source (112, 212), at least one high sensitivity differential current transformer (104, 203, 204) for generating imbalance signals (128, 227) representative of an imbalance current in at least one of the electrical motor and the three phase cable, wherein the at least one high sensitivity differential current transformer is disposed such that the at least one high sensitivity differential current transformer surrounds at least a portion of the three phase cable, and a processing subsystem (136, 236) for monitoring the health of at least one of the fluid lifting device and the three phase cable based on the imbalance signals.
17 Citations
19 Claims
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1. A system, comprising:
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a fluid lifting device located inside a well and comprising an electrical motor; a three phase cable for coupling the fluid lifting device to a power source; at least one high sensitivity differential current transformer for generating imbalance signals representative of an imbalance current in at least one of the electrical motor and the three phase cable, wherein the at least one high sensitivity differential current transformer is disposed such that the at least one high sensitivity differential current transformer surrounds at least a portion of the three phase cable; and a processing subsystem for monitoring health of at least one of the fluid lifting device and the three phase cable based on the imbalance signals, wherein the imbalance signals comprise first imbalance signals representative of the imbalance current in the electrical motor, and second imbalance signals representative of a total imbalance current in the electrical motor and the three phase cable. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
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18. A system, comprising:
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a fluid lifting device located inside a well, the fluid lifting device comprising an electrical motor; a three phase cable for coupling the fluid lifting device to a power source; a first high sensitivity differential current transformer for generating first imbalance signals representative of an imbalance current in the electrical motor, wherein the first high sensitivity differential current transformer is disposed such that the first high sensitivity differential current transformer surrounds a first portion of the three phase cable, and wherein the first high sensitivity differential current transformer is disposed inside the well; and a second high sensitivity differential current transformer for generating second imbalance signals representative of a total imbalance current in the electrical motor and the three phase cable, wherein the second high sensitivity differential current transformer is disposed such that the second high sensitivity differential current transformer surrounds a second portion of the three phase cable, and wherein the second high sensitivity differential current transformer is disposed outside the well; and a processing subsystem for monitoring health of the three phase cable based on the imbalance current in the electrical motor and the total imbalance current in the electrical motor and the three phase cable.
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19. A method for monitoring health of a three phase cable that couples a fluid lifting device to a power source, the method comprising:
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determining, by a processor, an imbalance current in an electrical motor disposed in the fluid lifting device based on first imbalance signals, wherein the first imbalance signals are provided by a first high-sensitivity differential current transformer; determining, by the processor, a total imbalance current in the electrical motor and the three phase cable based on second imbalance signals, wherein the second imbalance signals are provided by the first high-sensitivity differential current transformer; determining, by the processor, an imbalance current in the three phase cable based on the imbalance current in the electrical motor and the total imbalance current in the electrical motor and the three phase cable; and determining, by the processor, whether an insulation defect is present in the three phase cable based on the imbalance current in the three phase cable and a cable-insulation-defect threshold.
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Specification