Systems and methods for active power management in a medical device

Patent metadata

Field	Value
Publication number	US-11529481-B2
Application number	US-201916600741-A
Country	US
Kind code	B2
Filing date	Oct 14, 2019
Priority date	Oct 15, 2018
Publication date	Dec 20, 2022
Grant date	Dec 20, 2022

Abstract

A respiratory treatment device includes a blower for providing flow of breathable gas to a patient and one or more accessory devices. The respiratory treatment device includes active power management to distribute power from a power source that does not have sufficient power to simultaneously power the blower and the accessory devices. The active power management prioritizes power to the blower and limits, based on current measurements of the blower and the accessory devices, the power supplied to the accessory devices to keep the sum of the power drawn at or below the capacity of the power supply. When additional power is available, due reduced power consumption of the blower, the power to one or more accessory devices is raised beyond a target in order to compensate for when power was not supplied to the one or more accessory devices.

First claim

The invention claimed is:

1. A respiratory treatment apparatus comprising:
a power supply;
a pressure generator configured to generate a flow of air;
a heating element configured to heat the generated flow of air;
one or more sensors configured to generate sensor signals representing a property of the flow of air; and
a processing system configured to:
receive the sensor signals;
based on the received sensor signals, determine a control signal for controlling the heating element;
receive signals corresponding to current drawn by the pressure generator;
receive signals corresponding to current drawn by the heating element;
based on (1) the signals corresponding to current drawn by the pressure generator, (2) the signals corresponding to current drawn by the heating element, (3) the determined control signal for the heating element, and (4) power of the power supply, generate a new control signal for controlling the heating element; and
control operation of the heating element using the new control signal for controlling the heating element,

wherein generating the new control signal comprises, when the current drawn by the pressure generator and the current drawn by the heating element using the determined control signal for the heating element will cause current drawn by the respiratory treatment apparatus to exceed a maximum current of the power supply, generating the new control signal to reduce current drawn by the heating element.

2. The respiratory treatment apparatus of claim 1 , wherein the power that could be drawn by the pressure generator and the heating element combined exceeds the capability of the power supply.

3. The respiratory treatment apparatus of claim 1 , wherein when a sum of current drawn by the pressure generator and current that would be drawn by the heating element using the determined control signal for the heating element exceeds the maximum current of the power supply, generate the new control signal such that the new control signal will cause the heating element to draw less current than the current that would be drawn with the determined control signal.

4. The respiratory treatment apparatus of claim 1 , wherein when a sum of current drawn by the pressure generator and current that would be drawn by the heating element using the determined control signal for the heating element does not exceed the maximum current of the power supply, generate the new control signal such that the new control signal will cause the heating element to draw more current than the current that would be drawn with the determined control signal.

5. The respiratory treatment apparatus of claim 1 , wherein at least one of the one or more sensors is configured to generate sensor signals representing temperature of the air flow and the processing system is further configured to control the pressure generator based on the sensor signals representing temperature of the flow of air, and the flow of air is delivered to a patient interface via a tube coupled to the flow generator.

6. The respiratory treatment apparatus of claim 1 , wherein at least one of the one or more sensors is a pressure sensor configured to generate sensor signals representing pressure of the air flow and the control signal for controlling the heating element is determined based on the sensor signals representing pressure of the flow of air.

7. The respiratory treatment apparatus of claim 1 , wherein at least one of the one or more sensors is a flow sensor configured to generate sensor signals representing flow of the air flow and the processing system is configured to control the pressure generator based on the sensor signals representing flow of the flow of air and the control signal for controlling the heating element is determined based on the sensor signals representing flow of the flow of air.

8. The respiratory treatment apparatus of claim 1 , wherein the generated new control signal for controlling the heating element is controlled to accrue a heat deficit in a time period and return the accrued heat deficit in a subsequent time period.

9. The respiratory treatment apparatus of claim 1 , wherein the generated new control signal for controlling the heating element decreases the heat produced by the heating element during a first period and increases the heat produced by the heating element during a second period following the first period.

10. The respiratory treatment apparatus of claim 9 , wherein during the first period the power of the power supply equals the power consumed by the pressure generator and the heating element and during the second period the power of the power supply exceeds the power consumed by the pressure generator and the heating element.

11. An apparatus for treating a respiratory disorder in a patient, the apparatus comprising:
a power supply;
a pressure generator configured to generate a flow of breathable gas for treating the respiratory disorder;
a humidifier configured to store a supply of water to humidify the breathable gas and comprising a first heating element configured to heat the supply of water;
a second heating element configured to heat the humidified breathable gas in a hose configured to deliver the humidified breathable gas to the patient;
a transducer configured to generate a flow signal representing a property of the flow of breathable gas;
a controller configured to:
based on the flow signal, determine a first control signal for controlling the first heating element, and a second control signal for controlling the second heating element;
based on (1) measured current drawn by the pressure generator during operation of the pressure generator, (2) the first control signal, and (3) the second control signal, determine if power to be used by the apparatus exceeds a peak power of the power supply;
if it is determined that the power to be used by the apparatus exceeds the peak power of the power supply, modify the first control signal and/or the second control signal to decrease the power used by the first heating element and/or the second heating element; and
if it is determined that the power to be used by the apparatus does not exceed the peak power of the power supply, modify the first control signal and/or the second control signal to increase the power used by the first heating element and/or the second heating element.

12. The apparatus of claim 11 , wherein the first and second control signals are pulse width modulated signals.

13. The apparatus of claim 11 , wherein the first control signal is a first pulse width modulated signal and the second control signal is a second pulse width modulated signal that is offset in time from the first pulse width modulated control signal.

14. The apparatus of claim 11 , wherein, if it is determined that the power to be used by the apparatus does not exceed the peak power of the power supply, the first control signal and the second control signal are modified to increase the power used by the first heating element and the second heating element with priority given to the second heating element.

15. The apparatus of claim 11 , wherein, if it is determined that the power to be used by the apparatus exceeds the peak power of the power supply, modify the first control signal and the second control signal to decrease the power used by the first heating element and the second heating element with priority given to the second heating element.

16. The apparatus of claim 11 , wherein the first control signal is a first current set point provided to a proportional, proportional-differential, or proportional-integral controller configu

Assignees

• ResMed Pty Ltd

Inventors

• Bath Andrew Roderick
• Voon Rudi
• Creusot David
• Doudkine Dmitri Anatolievich
• Zhu Mike
• Panarello Adam

Classifications

• A61M16/1095

  in the connecting tubes · CPC title

• A61M2205/3334

  Measuring or controlling the flow rate · CPC title

• A61M2202/0208

  Oxygen · CPC title

• A61M2205/50

  with microprocessors or computers · CPC title

• A61M16/16

  Devices to humidify the respiration air {(A61M16/1045 takes precedence)} · CPC title