ESP pump flow rate estimation and control

1. A controller of a pump system, the controller comprising:

an input that receives measurements as to power supplied to a multiphase electric motor via a multiphase power cable;

circuitry to compensate for an asymmetry of the multiphase power cable on at least a portion of the measurements, and

wherein the controller processes the measurements to estimate a pump rate of a pump driven by the multiphase electric motor.

2. The controller of claim 1 , further comprising an output that outputs information to control the power supplied to the multiphase power cable.

3. The controller of claim 2 , wherein the information is based at least in part on the processing of at least one of the measurements.

4. The controller of claim 1 , wherein the multiphase electric motor comprises an IM motor.

5. The controller of claim 1 , wherein the multiphase electric motor comprises a PMS motor.

6. The controller of claim 1 , wherein the controller comprises a closed loop controller.

7. The controller of claim 1 , wherein the controller comprises a state space-based model controller.

8. The controller of claim 7 , wherein the state space-based model controller uses a model comprising rotor and stator resistance parameters that are dynamically adapted based at least in part on operational conditions of the pump.

9. The controller of claim 7 , wherein the state space-based model comprises a system variable vector and an excitation vector.

10. The controller of claim 7 , wherein the state space-based model is a tracking model that comprises a correction term that is based at least in part on feedback gain and prediction error.

11. The controller of claim 1 , wherein the controller is a rotor speed estimator controller.

12. The controller of claim 1 , wherein the controller processes the measurements to estimate a temperature estimate of the multiphase electric motor.

13. The controller of claim 12 , wherein the temperature estimate is based at least in part on a rotor time constant.

14. The controller of claim 1 , wherein the controller processes the measurements to output a control signal that controls the multiphase electric motor to reduce oscillation of a shaft of the multiphase electric motor connecting the multiphase electric motor to the pump.

15. The controller of claim 14 , wherein the control signal is a speed control signal.

16. The controller of claim 1 , wherein the controller processes the measurements to output at least one quality control metric.

17. The controller of claim 16 , wherein the at least one quality control metric comprises at least one of a winding quality control metric and an insulation quality control metric.

18. A method of providing a controller of a pump system, the method comprising:

providing an input of the controller, wherein the input is configured to receive measurements as to power supplied to a multiphase electric motor via a multiphase power cable; and

providing circuitry to compensate for an asymmetry of the multiphase power cable on at least a portion of the measurements,

wherein the controller processes the measurements to estimate a pump rate of a pump driven by the multiphase electric motor.

19. The method of claim 18 further comprising:

providing an output that outputs information to control the power supplied to the multiphase power cable.

20. An electric submersible pump system comprising:

a controller that comprises an input that receives measurements as to power supplied to a multiphase electric motor via a multiphase power cable, the controller configured to:

process the measurements to estimate a pump rate of a fluid pump driven by the multiphase electric motor;

compensate for an asymmetry of the multiphase power cable on at least a portion of the measurements; and

estimate the pump rate of the fluid pump without input from downhole sensors.