Portable controller with integral power source for mechanical circulation support systems
View Patent ↗A portable external device for a mechanical circulation support system includes first and second power sources, e.g. batteries and control electronics for redundant uninterrupted operation of an implantable blood pump. The control and power source module may be configured to accommodate a variety of wearable configurations for patient convenience and comfort.
1. A device for a mechanical circulation support (MCS) system comprising:
control electronics configured to control an electric motor according to a field-oriented control (FOC) algorithm, the electric motor being configured to drive an implantable pump included in the MCS system.
2. The device of claim 1 , wherein the control electronics are further configured to:
determine an observer error for an observer that is used to control the electric motor according to the FOC algorithm while controlling the electric motor according to the FOC algorithm; and
switch from using the FOC algorithm for controlling the electric motor to using a control algorithm other than the FOC algorithm for controlling the electric motor based on the determined observer error.
3. The device of claim 2 , wherein the observer error comprises an error parameter.
4. The device of claim 2 , wherein the observer error comprises an error of an estimated back electromotive force (EMF) of the electric motor.
5. The device of claim 2 , wherein the control electronics are further configured to:
while controlling the electric motor according to the FOC algorithm, estimate the back electromotive force (EMF) of the electric motor;
determine an error of the estimated back EMF;
compare the error of the estimated back EMF to a threshold; and
control the electric motor employing the control algorithm other than the FOC algorithm if the error of the estimated back EMF is greater than the threshold.
6. The device of claim 5 , wherein the control electronics are further configured to:
determine a rotational position of a rotor of the electric motor based on the estimated back EMF of the electric motor.
7. The device of claim 6 , wherein the control electronics are further configured to:
determine a pulse width modulated (PWM) voltage signal to send to the electric motor to drive an implantable pump based on the rotational position of the rotor of the electric motor.
8. The device of claim 5 , wherein the control electronics are further configured to:
sense current from the electric motor; and
estimate the back EMF of the electric motor based on the sensed current from the electric motor.
9. The device of claim 2 , wherein the observer compares measureable parameters of a motor driving pump to a model.
10. The device of claim 2 , wherein the observer comprises at least one of a sliding mode observer and a luenberger observer.
11. The device of claim 2 , wherein the control electronics are further configured to:
determine whether the observer error is acceptable; and
switch from using the FOC algorithm for controlling the electric motor to using the control algorithm other than the FOC algorithm for controlling the electric motor in response to determining that the observer error is not acceptable.
12. The device of claim 11 , wherein the control electronics are further configured to:
continue to use the FOC algorithm for controlling the electric motor in response to determining that the observer error is acceptable.
13. The device of claim 1 , wherein the pump is configured to receive blood from a source and pump the blood to one or more destinations within a body of a patient.
14. The device of claim 1 , wherein the device is external to a patient in which the implantable pump is implanted.
15. A method for driving an implantable pump in a mechanical circulation support (MCS) system comprising:
controlling an electric motor according to a field-oriented control (FOC) algorithm, the electric motor being configured to drive the implantable pump included in the MCS system.
16. The method of claim 15 , further comprising:
determining an observer error for an observer that is used to control the electric motor according to the FOC algorithm while controlling the electric motor according to the FOC algorithm; and
switching from using the FOC algorithm for controlling the electric motor to using a control algorithm other than the FOC algorithm for controlling the electric motor based on the determined observer error.
17. The method of claim 16 , wherein the observer error comprises an error parameter.
18. The method of claim 16 , wherein the observer error comprises an error of an estimated back electromotive force (EMF) of the electric motor.
19. The method of claim 16 , further comprising:
while controlling the electric motor according to the FOC algorithm, estimating the back electromotive force (EMF) of the electric motor,
wherein switching from using the FOC algorithm for controlling the electric motor to using the control algorithm other than the FOC algorithm for controlling the electric motor based on the determined observer error comprises:
determining an error of the estimated back EMF;
comparing the error of the estimated back EMF to a threshold; and
controlling the electric motor employing the control algorithm other than the FOC algorithm if the error of the estimated back EMF is greater than the threshold.
20. The method of claim 19 , further comprising:
determining a rotational position of a rotor of the electric motor based on the estimated back EMF of the electric motor.
21. The method of claim 20 , further comprising:
determining a pulse width modulated (PWM) voltage signal to send to the electric motor to drive an implantable pump based on the rotational position of the rotor of the electric motor.
22. The method of claim 19 , wherein estimating the back EMF of the electric motor comprises:
sensing current from the electric motor; and
estimating the back EMF of the electric motor based on the sensed current from the electric motor.
23. The method of claim 16 , wherein the observer compares measureable parameters of a motor driving pump to a model.
24. The method of claim 16 , wherein the observer comprises at least one of a sliding mode observer and a luenberger observer.
25. The method of claim 16 , wherein switching from using the FOC algorithm for controlling the electric motor to using the control algorithm other than the FOC algorithm for controlling the electric motor based on the determined observer error comprises:
determining whether the observer error is acceptable; and
switching from using the FOC algorithm for controlling the electric motor to using the control algorithm other than the FOC algorithm for controlling the electric motor in response to determining that the observer error is not acceptable.
26. The method of claim 25 , wherein switching from using the FOC algorithm for controlling the electric motor to using the control algorithm other than the FOC algorithm for controlling the electric motor based on the determined observer error further comprises:
continuing to use the FOC algorithm for controlling the electric motor in response to determining that the observer error is acceptable.
27. The method of claim 15 , wherein the pump is configured to receive blood from a source and pump the blood to one or more destinations within a body of a patient.
28. The method of claim 15 , wherein controlling an electric motor according to the FOC algorithm comprises:
controlling, with a device, the electric motor according to the FOC algorithm.
29. The method of claim 28 , wherein the device is external to a patient in which the implantable pump is implanted.