TETS coil alignment conditions algorithm
A TETS having an external controller having a power source, a transmission coil in communication with the external controller, a receiving coil configured for transcutaneous inductive communication with the transmission coil, and an implantable controller in communication with the receiving coil and an implantable blood pump. The implantable controller has a battery configured to receive power from the receiving coil and the external controller is configured to categorize power transfer states based on predetermined thresholds of efficiency and power demand, and user display states (associated with optional configurable notifications) based on the power transfer states and predetermined temperature thresholds of the transmission coil.
1. A transcutaneous energy transfer system, comprising:
an external controller having a power source and a processing circuitry;
a transmission coil in communication with the external controller;
a receiving coil configured for transcutaneous inductive communication with the transmission coil; and
an implantable controller in communication with the receiving coil and an implantable blood pump, the implantable controller having a battery configured to receive power from the receiving coil,
the processing circuitry being configured to:
determine, based on a temperature of the transmission coil and a power transfer efficiency between the transmission coil and the receiving coil, an operating condition of the processing circuitry from a plurality of operating conditions, wherein each operating condition of the plurality of operating conditions is associated with a corresponding urgency of user intervention, and wherein the plurality of operating conditions comprises:
a first operating condition associated with no urgency of user intervention, wherein the first operating condition occurs when the temperature of the transmission coil is below a first predetermined transmission coil temperature and when the power transfer efficiency between the transmission coil and the receiving coil is above a first predetermined threshold of at least 80%;
a second operating condition associated with a mild urgency of user intervention, wherein the second operating condition occurs when either the power transfer efficiency between the transmission coil and the receiving coil drops below a second predetermined threshold between 65% and 80% or the temperature of the transmission coil rises above a second predetermined transmission coil temperature; and
generate a notification associated with the operating condition of the processing circuitry.
2. The system of claim 1 , wherein the plurality of operating conditions further comprises:
a third operating condition associated with a moderate urgency of user intervention, wherein the third operating condition occurs when either the power transfer efficiency between the transmission coil and the receiving coil drops below a third predetermined threshold or the temperature of the transmission coil rises above a third predetermined transmission coil temperature; and
a fourth operating condition associated with a high urgency of user intervention, wherein the fourth operating condition occurs when either the power transfer efficiency between the transmission coil and the receiving coil is below a fourth predetermined threshold or there is a loss of power transfer between the transmission coil and the receiving coil.
3. The system of claim 1 , wherein the external controller further includes a display.
4. The system of claim 2 , wherein the third predetermined threshold is within the range of 55% to 65%.
5. The system of claim 2 , wherein the second predetermined transmission coil temperature is within the range of 41° C. to 43° C.
6. The system of claim 2 , wherein the third predetermined transmission coil temperature is within the range of 44° C. to 60° C.
7. The system of claim 2 , wherein the first predetermined transmission coil temperature is below 41° C.
8. The system of claim 2 , wherein the first operating condition occurs when an internal controller power demand is less than a predetermined power demand threshold, wherein the second operating condition occurs when the internal controller power demand is less than the predetermined power demand threshold, wherein the third operating condition occurs when the internal controller power demand is greater than the predetermined power demand threshold, and wherein the fourth operating condition occurs when the internal controller power demand is greater than the predetermined power demand threshold.
9. The system of claim 8 , wherein the predetermined power demand threshold is 30 Watts.
10. A method comprising:
obtaining, by processing circuitry, a temperature of a transmission coil of a transcutaneous energy transfer system and a power transfer efficiency between the transmission coil and a receiving coil of the transcutaneous energy transfer system, wherein the transcutaneous energy transfer system comprises:
an external controller having the processing circuitry;
the transmission coil;
the receiving coil; and
an implantable controller in communication with the receiving coil and an implantable blood pump;
determining, based on the temperature of the transmission coil and the power transfer efficiency between the transmission coil and the receiving coil, an operating condition of the processing circuitry from a plurality of operating conditions, wherein each operating condition of the plurality of operating conditions is associated with a corresponding urgency of user intervention, and wherein the plurality of operating conditions comprises:
a first operating condition associated with no urgency of user intervention, wherein the first operating condition occurs when the temperature of the transmission coil is below a first predetermined transmission coil temperature and when the power transfer efficiency between the transmission coil and the receiving coil is above a first predetermined threshold of at least 80%;
a second operating condition associated with a mild urgency of user intervention, wherein the second operating condition occurs when either the power transfer efficiency between the transmission coil and the receiving coil drops below a second predetermined threshold between 65% and 80% or the temperature of the transmission coil rises above a second predetermined transmission coil temperature; and
generating a notification associated with the operating condition of the processing circuitry.
11. The method of claim 10 , wherein the plurality of operating conditions further comprises:
a third operating condition associated with a moderate urgency of user intervention, wherein the third operating condition occurs when either the power transfer efficiency between the transmission coil and the receiving coil drops below a third predetermined threshold or the temperature of the transmission coil rises above a third predetermined transmission coil temperature; and
a fourth operating condition associated with a high urgency of user intervention, wherein the fourth operating condition occurs when either the power transfer efficiency between the transmission coil and the receiving coil is below a fourth predetermined threshold or there is a loss of power transfer between the transmission coil and the receiving coil.
12. The method of claim 11 , wherein the third predetermined threshold is within the range of 55% to 65%.
13. The method of claim 11 , wherein the second predetermined transmission coil temperature is within the range of 41° C. to 43° C.
14. The method of claim 11 , wherein the third predetermined transmission coil temperature is within the range of 44° C. to 60° C.
15. The method of claim 11 , wherein the first predetermined transmission coil temperature is below 41° C.
16. The method of claim 11 , wherein the first operating condition occurs when an internal controller power demand is less than a predetermined power demand threshold, wherein the second operating condition occurs when the internal controller power demand is less than the predetermined power demand threshold, wherein the third operating condition occurs when the internal controller power demand is greater than the predetermined power demand threshold, and wherein the second operating condition occurs when the internal controller power demand is greater than the predetermined power demand threshold.