System and method for measuring discharge parameters relating to an electric submersible pump

1. An electric submersible pump (ESP) monitoring system, comprising:

a base monitoring unit; and

a discharge monitoring unit that is communicably coupled to the base monitoring unit via a ground path;

wherein the discharge monitoring unit is hydraulically coupled to a pump discharge of a pump of an ESP system and is configured to:

measure at least one discharge parameter relating to the pump discharge; and

transmit data corresponding to the at least one discharge parameter to the base monitoring unit via the ground path; and

wherein the base monitoring unit is electrically connected to a motor of the ESP system and is configured to:

measure at least one base parameter relating to the motor and/or a pump intake of the pump;

receive the transmitted data corresponding to the at least one discharge parameter from the discharge monitoring unit;

combine the data corresponding to the at least one discharge parameter and data corresponding to the at least one base parameter; and

transmit the combined data to an ESP surface unit via an ESP power cable.

2. The ESP monitoring system of claim 1 , wherein the ground path comprises an armor of the ESP power cable.

3. The ESP monitoring system of claim 1 , wherein the ground path comprises any combination of an armor of the ESP power cable, a housing of one or more components of the ESP system, a production tubing, and a casing of a wellbore.

4. The ESP monitoring system of claim 1 , wherein the at least one base parameter comprises at least one of a downhole vibration, a motor oil temperature, a motor winding temperature, an intake pressure, an intake temperature, a water ingress, a current leakage, and a wye voltage.

5. The ESP monitoring system of claim 1 , wherein the at least one discharge parameter comprises at least one of a discharge pressure, a discharge temperature, or a vibration near the pump discharge.

6. The ESP monitoring system of claim 1 , wherein the discharge monitoring unit is configured to:

measure the at least one discharge parameter by recording a pressure signal;

convert the pressure signal to an output frequency; and

transmit the output frequency to the base monitoring unit as the data corresponding to the at least one discharge parameter.

7. The ESP monitoring system of claim 6 , wherein the base monitoring unit is electrically connected to a motor wye point of the motor, and wherein the base monitoring unit is configured to:

receive the transmitted data from the discharge monitoring unit by reading the output frequency from the ground path using the motor wye point as a reference;

convert the output frequency to pressure information;

combine the pressure information with any pressure information recorded by the base monitoring unit; and

transmit the combined pressure information to the ESP surface unit via the ESP power cable.

8. The ESP monitoring system of claim 6 , wherein the discharge monitoring unit converts the pressure signal to an output voltage or an output current rather than the output frequency.

9. The ESP monitoring system of claim 1 , wherein the discharge monitoring unit comprises a pressure transducer that is rated for downhole conditions.

10. The ESP monitoring system of claim 1 , wherein the transmission from the base monitoring unit to the ESP surface unit is configured to overwhelm the transmission from the discharge monitoring unit to the base monitoring unit to ensure that the combined data reach the ESP surface unit.

11. The ESP monitoring system of claim 1 , wherein the base monitoring unit is configured to alternate between receiving the transmitted data from the discharge monitoring unit and transmitting the combined data to the ESP surface unit.

12. The ESP monitoring system of claim 1 , wherein the base monitoring unit is configured to request the data corresponding to the at least one discharge parameter from the discharge monitoring unit.

13. The ESP system of claim 12 , wherein the base monitoring unit is configured to send the requests to the discharge monitoring unit in a cycle such that the data corresponding to each discharge parameter are transmitted separately.

14. The ESP monitoring system of claim 1 , wherein the discharge monitoring unit comprises a power source.

15. The ESP monitoring system of claim 14 , wherein the power source comprises a power-generation device that is configured to generate power downhole.

16. A method for measuring and transmitting parameters relating to an electric submersible pump (ESP) system, comprising:

providing an ESP monitoring system, wherein the ESP monitoring system comprises a base monitoring unit and a discharge monitoring unit that are communicably coupled via a ground path, and wherein the discharge monitoring unit is hydraulically coupled to a pump discharge of a pump of the ESP system and the base monitoring unit is electrically connected to a motor of the ESP system;

measuring at least one base parameter relating to the motor and/or a pump intake of the pump using the base monitoring unit;

measuring at least one discharge parameter relating to the pump discharge using the discharge monitoring unit;

transmitting data corresponding to the at least one discharge parameter from the discharge monitoring unit to the base monitoring unit via a ground path;

combining, via the base monitoring unit, the data corresponding to the at least one discharge parameter and data corresponding to the at least one base parameter; and

transmitting the combined data from the base monitoring unit to an ESP surface unit via an ESP power cable.

17. The method of claim 16 , wherein transmitting the data corresponding to the at least one discharge parameter via the ground path comprises transmitting the data via an armor of the ESP power cable.

18. The method of claim 16 , wherein transmitting the data corresponding to the at least one discharge parameter via the ground path comprises transmitting the data via any combination of an armor of the ESP power cable, a housing of one or more components of the ESP system, a production tubing, and a casing of a wellbore.

19. The method of claim 16 , wherein measuring the at least one base parameter comprises measuring at least one of a downhole vibration, a motor oil temperature, a motor winding temperature, an intake pressure, an intake temperature, a water ingress, a current leakage, and a wye voltage.

20. The method of claim 16 , wherein measuring the at least one discharge parameter comprises measuring at least one of a discharge pressure, a discharge temperature, or a vibration near the pump discharge.

21. The method of claim 16 , comprising:

measuring, via the discharge monitoring unit, the at least one discharge parameter by recording a pressure signal;

converting, via the discharge monitoring unit, the pressure signal to an output frequency; and

transmitting the output frequency from the discharge monitoring unit to the base monitoring unit as the data corresponding to the at least one discharge parameter.

22. The method of claim 21 , comprising:

reading, via the base monitoring unit, the output frequency from the ground path using a motor wye point as a reference;

converting, via the base monitoring unit, the output frequency to pressure information;

combining, via the base monitoring unit, the pressure information with any pressure information recorded by the base monitoring unit; and

transmitting the combined pressure information from the base monitoring unit to the ESP surface unit via the ESP power cable.

23. The method of claim 21 , comprising converting the pressure signal to an output voltage or an output current rather than the output frequency.

24. The method of claim 16 , comprising powering the discharge monitoring unit via a power source that is coupled to the discharge monitoring unit.

25. An electric submersible pump (ESP) system, comprising:

a shaft;

a motor configured to rotate the shaft in response to receiving power via an ESP power cable;

a pump that is operatively coupled to the shaft, wherein the pump comprises a pump intake and a pump discharge; and

an ESP monitoring system, comprising:

a base monitoring unit; and

a discharge monitoring unit that is communicably coupled to the base monitoring unit via a ground path;

wherein the discharge monitoring unit is hydraulically coupled to the pump discharge and is configured to:

measure at least one discharge parameter relating to the pump discharge; and

transmit data corresponding to the at least one discharge parameter to the base monitoring unit via the ground path; and

wherein the base monitoring unit is electrically connected to the motor and is configured to:

measure at least one base parameter relating to the motor and/or the pump intake;

receive the transmitted data corresponding to the at least one discharge parameter from the discharge monitoring unit;

combine the data corresponding to the at least one discharge parameter and data corresponding to the at least one base parameter; and

transmit the combined data to an ESP surface unit via the ESP power cable.