CN116685375A - Run-time residual algorithm - Google Patents

Abstract

The present disclosure describes an apparatus for providing an accurate estimate of the remaining run time of a battery. The apparatus includes an electricity meter and processing circuitry coupled to the electricity meter. The processing circuitry may receive an indicator of remaining battery capacity from the fuel gauge. The processing circuitry may calculate remaining battery energy based on the remaining battery capacity and further based on an amount of power expected to be used by the battery load during an expected alert time. The processing circuitry may calculate a remaining runtime based on the remaining battery energy. A method and system are also described.

Description

Run-time residual algorithm

Technical Field

The present technology relates generally to techniques for battery management. More particularly, the present technology relates to techniques for accurately determining the run-time remaining of a battery.

Background

Rechargeable batteries provide power in a variety of systems. The full charge capacity of a battery is a measure of the maximum chemical capacity of a rechargeable battery. The remaining operational time of the rechargeable battery reflects the state of charge of the battery. Since knowledge of the remaining run time is important to patient safety, it is often desirable to more accurately determine the remaining run time during all phases of battery operation.

Disclosure of Invention

Embodiments described herein relate to an apparatus including an electricity meter and processing circuitry coupled to the electricity meter. The processing circuitry may receive an indicator of remaining battery capacity from the fuel gauge. The processing circuitry may then calculate remaining battery energy based on the remaining battery capacity and further based on an amount of power expected to be used by the battery load during the expected alert time. The processing circuitry may calculate a remaining run time other than the alert time based on the remaining battery energy.

Advantages and additional features of the disclosed subject matter are set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the disclosed subject matter as described herein, including the detailed description which follows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description and the following detailed description present embodiments of the presently disclosed subject matter, and are intended to provide an overview or framework for understanding the nature and character of the presently disclosed subject matter as it is claimed. The accompanying drawings are included to provide a further understanding of the subject matter of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments of the presently disclosed subject matter and together with the description serve to explain the principles and operation of the presently disclosed subject matter. Further, the drawings and description are intended to be illustrative only and are not intended to limit the scope of the claims in any way.

Drawings

Fig. 1 is a block diagram of an apparatus including a battery management system for managing batteries according to an embodiment.

Fig. 2 is a block diagram illustrating a battery management system according to an embodiment.

Fig. 3 is a flowchart illustrating a method of control logic for battery management according to an embodiment.

Detailed Description

Fig. 1 is a block diagram of an apparatus 100 including a battery management system for managing batteries according to operations, processes, methods, and methodologies of an embodiment. The apparatus 100 may comprise any combination of hardware or logic components referred to herein. The device 100 may include components of a ventricular assist device or for controlling its operation. The device 100 may include or be coupled to any other device, such as other devices required to effect treatment of a patient.

The apparatus 100 may include processing circuitry in the form of a processor 102, which may be a microprocessor, a multi-core processor, a multi-threaded processor, an ultra-low voltage processor, an embedded processor, or other known processing element. Processor 102 may be part of a system-on-a-chip, wherein processor 102 and other components described herein are formed in a single integrated circuit.

The battery 128 may power the device 100, although in examples where the device 100 is in a fixed position, the device 100 may have a power source coupled to the power grid. The battery 128 may be a lithium ion battery, although the embodiment is not limited thereto. The battery management apparatus 130 may be included in the device 100, or the battery management apparatus 130 may be part of an external device coupled to the device 100 to track a state of charge (SoC) of the battery 128. A power block 132 or other power source coupled to the network may be coupled to the battery management device 130 to charge the battery 128. In some examples, the power block 132 may be replaced with a wireless power receiver to obtain power wirelessly. Further details regarding battery management device 130 are provided below with reference to fig. 2.

Fig. 2 is a block diagram illustrating a battery management device 130 according to an embodiment. The battery management device 130 may be used to monitor other parameters of the battery 128, such as the state of health (SoH) and the state of function (SoF) of the battery 128, in order to provide a failure prediction. The battery management device 130 may include battery monitoring circuitry (e.g., fuel gauge 202) and runtime residual circuitry 204 to determine runtime residual in the battery.

The run-time residual circuitry 204 provides greater accuracy to the output of the fuel gauge 202 by taking into account the additional energy used to provide alarms and other indicators during low battery conditions. In an embodiment, the run-time residual circuitry 204 is included on the processor 102 (fig. 1) of the apparatus 100, although the embodiment is not so limited. For example, in some embodiments, the fuel gauge 202 may perform some of the functions of the runtime residual circuitry 204.

The battery 128 capacity corresponds to the amount of charge that can be accumulated during charging of the battery 128, stored under open circuit conditions, and released during discharging of the battery 128. When the battery 128 is discharged at a constant current (e.g., during a discharge cycle according to the methods described herein, or during normal operation of the device 100), the battery 128 capacity is given by equation (1):

C _d ＝I·t _d (1)

wherein t is _d Is the discharge duration and I is the current. When the discharge duration is expressed in hours, a typical unit of capacity of the battery 128 is amp-hours (AH).

When the battery 128 is inactive or in an equilibrium state, the SoC of the battery 128 indicates the voltage at the terminals 214, 216 of the battery 128. The mathematical relationship between SoC and balance voltage is a known relationship and is based on battery type. When the battery 128 is not in an equilibrium state, current flows through the battery 128. In this case, the actual voltage is lower than the equilibrium voltage by an amount that can be calculated using ohm's law for the known internal resistance of the battery 128.

Ohm's law applies to the operation of some fuel gauges, such as fuel gauge 202. The electricity meter 202 may use ohm's law by: the internal resistance of the monitored battery 128 is measured, the internal resistance is multiplied by the measured current to determine an intermediate voltage value, and then the measured terminal voltage is offset by the intermediate voltage value to obtain an estimate of the equilibrium voltage of the battery 128. The estimate of the equilibrium voltage may then be used to calculate the available battery 128 capacity. Other components and algorithms (including coulomb counters and other devices) may be added to improve the accuracy of the fuel gauge 202. The fuel gauge 202 may provide capacity information, voltage information, temperature information, capacity update status, coulomb count, depth of discharge, error messages, and other information to other systems (e.g., the run-time residual circuitry 204).

The fuel gauge 202 may be based on the available battery 128 capacity C _d And infer the run-time remaining of battery 128 based on the amount of current drawn by load 212:

run time remaining = C _d Current drawn (2)

However, the runtime residuals reported by the fuel gauge 202 do not take into account the energy required to perform the functions typically performed during low battery conditions. Such functions may include, for example, sounding an alarm for a fixed amount of time. Additionally, the electricity meter 202 may not consider the energy that may be provided by the power block 132 during low power conditions or other conditions. Embodiments provide run-time residual circuitry 204 for more accurate calculation of run-time residual.

The run-time remaining circuitry 204 reports the remaining energy E to be reported by the fuel gauge 202 _{Electricity meter} As input 206 and gives the runtime residual T _Run-time Is output 208 of (a). The run-time residual circuitry 204 may also use the power sensor 210 to measure an average power P consumed by the load 212 or averaged by a low-pass filter associated with the power sensor 210 or by rolling averages performed in the processor 102 _{Average of} . The run-time residual circuitry 204 determines the amount of energy that will be required to run the device 100 during the amount of time that the alert signal is transmitted. For example, the number of the cells to be processed,the run-time remaining circuitry 204 may determine the amount of energy to be used to run the device 100 for a fixed amount of alert time. The alert time may be fixed by the device 100 manufacturer and may represent the amount of time (in seconds or minutes) that the alert signal will be provided by the battery 128 during a low battery condition before the battery 128 is turned off and the alert signal is terminated. The run-time residual circuitry 204 may be implemented by multiplying the alert time by the average load power P _{Average of} To determine the energy E _Operation Is a combination of the amounts of (a) and (b).

Energy E is also required to sound an alarm _Alert . Final run-time residual T reported to user _Run-time Alert times should be excluded. Thus, next, the runtime residual circuitry 204 decrements E by following equation (3) _Alert To determine the remaining runtime energy E _Run-time ：

E _Run-time ＝E _{Electricity meter} -E _Operation -E _Alert (3)

Run-time residual T _Run-time The runtime energy E can be determined by following equation (4) _Run-time Divided by average load power P _{Average of} To calculate:

T _run-time ＝E _Run-time /P _{Average of} (4)

Fig. 3 is a flow chart of a method 300 for battery management according to an embodiment. The method 300 may be implemented by circuitry executing on the processor 102 (e.g., the runtime residual circuitry 204 (fig. 2)), the fuel gauge 202 circuitry (fig. 2), or other components of the battery management device 130 (fig. 1 and 2).

The method 300 may begin at operation 302, where the runtime residual circuitry receives an indicator of residual battery capacity.

The method 300 may continue with operation 304 in which the run-time remaining circuitry calculates remaining battery energy based on the remaining battery capacity and further based on the amount of power expected to be used by the battery load during the expected alert time. The runtime residual circuitry 204 may decrement the residual runtime by the expected alert time. The expected alert time may be defined as the amount of time that the device 100 will provide a low energy alert. The run-time remaining circuitry 204 may decrement the remaining battery energy by an amount of energy used to power the alarm during the expected alarm time. The amount of expected energy to provide a low energy alert may be calculated based on the average load power.

The method 300 may continue with operation 306, wherein the runtime residual circuitry 204 calculates a residual runtime based on the residual battery 128 energy. The run-time residual circuitry 204 may decrement this value of the residual battery 128 energy by the amount of energy used to power the alarm during the expected alarm time.

Referring again to fig. 1, other components that may be included in the apparatus 100 are described. The processor 102 may communicate with the system memory 104 via an interconnect 106 (e.g., a bus). Any number of memory devices may be used to provide a given amount of system memory. By way of example, the memory 104 may be Random Access Memory (RAM). However, any other type of memory may be included. Permanent storage may also be provided by the storage device 108. The storage 108 may also be coupled to the processor 102 via the interconnect 106. The storage 108 may include a disk drive, a flash memory card, a Universal Serial Bus (USB) flash drive, and the like.

These components may communicate via an interconnect 106. Interconnect 106 may include any number of technologies including Industry Standard Architecture (ISA), enhanced ISA (EISA), peripheral Component Interconnect (PCI), extended peripheral component interconnect (PCIx), PCI express (PCIe), or any number of other technologies. Interconnect 106 may be a proprietary bus.

Interconnect 106 may couple processor 102 to transceiver 110. The transceiver 110 may use any number of frequencies and protocols, IEEE or bluetooth protocols, although the embodiments are not limited to these protocols. A transceiver 110 may be included to communicate with devices or services in the cloud 112 via a local area network protocol or a wide area network protocol.

A Network Interface Controller (NIC) 114 may be included to provide wired communication to other devices or systems through the cloud 112. The wired communication may provide an ethernet connection or may be based on other types of networks. The interconnect 106 may couple the processor 102 to a sensor interface 116 for connecting additional devices or subsystems. These additional devices may include sensors 118, such as optical light sensors, camera sensors, temperature sensors, and the like. The interface 116 may further be used to connect the device 100 to an actuator 120, such as a power switch, a valve actuator, an audible sound generator, a visual warning device, and the like.

In some alternative examples, various input/output (I/O) devices may be present within or connected to device 100. For example, a display or other output device 122 may be included to display information, such as sensor readings, fuel gauge diagnostic outputs, and the like. An input device 124, such as a button, touch screen, or keyboard, may be included to accept input. Output device 122 may include any number of forms of audio or visual display, including simple visual outputs such as binary status indicators (e.g., light Emitting Diodes (LEDs)) and multi-character visual outputs, or more complex outputs such as display screens (e.g., liquid Crystal Display (LCD) screens), wherein the output of characters, graphics, multi-media objects, etc. is generated or produced by operation of device 100. In the context of the present system, display or console hardware may be used to provide output of medical devices (including implantable medical devices) and to receive input of medical devices; identifying a status of the medical device or a related/connected device; or perform any other number of management or supervisory functions.

The storage 108 may include instructions 125 in the form of software, firmware, or hardware commands to implement the techniques described herein. Although such instructions 125 are shown as blocks of code included in the memory 104 and storage 108, it is understood that any of these blocks of code may be replaced with hardwired circuitry, such as hardwired circuitry built into an Application Specific Integrated Circuit (ASIC).

In one example, the instructions 125 provided via the memory 104, the storage 108, or the processor 102 may be implemented as a non-transitory machine-readable medium 126 comprising code for directing the processor 102 to perform electronic operations in the apparatus 100. The processor 102 may access the non-transitory machine-readable medium 126 through the interconnect 106. For example, the non-transitory machine-readable medium 126 may be implemented by the device described for the storage device 108, or may include a particular storage unit, such as an optical disk, a flash drive, or any number of other hardware devices. The non-transitory machine-readable medium 126 may include instructions to direct the processor 102 to perform a particular sequence of actions or flow, for example, as described with respect to the flowcharts and block diagrams of the operations and functionality described above. The terms "machine-readable medium" and "computer-readable medium" as used herein are interchangeable.

In other examples, a machine-readable medium further includes any tangible medium capable of storing, encoding or carrying instructions for execution by a machine and that cause the machine to perform any one or more of the methodologies of the present disclosure, or capable of storing, encoding or carrying data structures utilized by or associated with such instructions. Thus, a "machine-readable medium" may include, but is not limited to, solid-state memories, as well as optical and magnetic media. Specific examples of machine-readable media include non-volatile memory including, by way of example, but not limitation, semiconductor memory devices (e.g., electrically programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM)) and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disk; and CD-ROM and DVD-ROM discs. The instructions implemented by the machine-readable medium may further be transmitted or received over a communications network using a transmission medium via a network interface device utilizing any of a number of transmission protocols, such as the hypertext transfer protocol (HTTP).

The machine-readable medium may be provided by a storage or other device capable of hosting data in a non-transitory format. In one example, information stored or otherwise provided on a machine-readable medium may represent instructions, such as the instructions themselves or the format from which the instructions may be derived. The format from which the instructions may be derived may include source code, encoded instructions (e.g., in compressed or encrypted form), packaged instructions (e.g., divided into multiple packages), and so forth. Information representing instructions in a machine-readable medium may be processed by processing circuitry into instructions to implement any of the operations discussed herein. For example, deriving instructions from the information (e.g., for processing by processing circuitry) may include: compiling information (e.g., from source code, object code, etc.), interpreting, loading, organizing (e.g., dynamically or statically linked), encoding, decoding, encrypting, decrypting, packaging, unpacking into instructions, or otherwise manipulating into instructions.

The various aspects disclosed herein may be combined in different combinations than those specifically presented in the specification and drawings. It should also be appreciated that, depending on the example, certain acts or events of any of the processes or methods described herein can be performed in a different order, may be added, combined, or omitted entirely (e.g., not all of the described acts or events may be required to perform the techniques). Additionally, although certain aspects of the present disclosure are described as being performed by a single module or unit for clarity, the techniques of this disclosure may be performed by a unit or combination of modules associated with, for example, a medical device.

In one or more examples, the techniques described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored as one or more instructions or code on a computer-readable medium and executed by a hardware-based processing unit. The computer-readable medium may include a non-transitory computer-readable medium corresponding to a tangible medium, such as data storage medium 23322 1pwcn

(e.g., RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer).

The instructions may be executed by one or more processors, such as one or more Digital Signal Processors (DSPs), general purpose microprocessors, application Specific Integrated Circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Thus, the term "processor" as used herein may refer to any of the foregoing structure or any other physical structure suitable for implementation of the described techniques. In addition, the present technology may be fully implemented in one or more circuits or logic elements.

Claims (16)

1. An apparatus, comprising:

an electricity meter; and

processing circuitry coupled to the electricity meter and configured to:

receiving an indicator of remaining battery capacity from the fuel gauge;

calculating a remaining battery energy based on the remaining battery capacity and further based on an amount of power expected to be used by the battery load during an expected alert time; and

a remaining run time other than the alert time is calculated based on the remaining battery energy.

2. A system, comprising:

an electricity meter to determine a remaining battery capacity; and

a battery operatively coupled to the fuel gauge; and

a battery management system comprising one or more processors operably coupled to the battery and configured to:

receiving an indicator of remaining battery capacity from the fuel gauge;

calculating a remaining battery energy based on the remaining battery capacity and further based on an amount of power expected to be used by the battery load during an expected alert time; and

and calculating a remaining runtime based on the remaining battery energy.

3. The apparatus of claim 1, wherein the remaining run-time decrements the expected alert time, and wherein the expected alert time is an amount of time that the processing circuitry will provide an alert.

4. The apparatus of claim 2, wherein the remaining battery energy is further decremented by an amount of energy used to power an alarm during the expected alarm time.

5. The device of claim 1, wherein the processing circuitry is further configured to calculate an amount of expected energy to provide an alert based on an average load power.

6. The device of claim 1, wherein the processing circuitry is further configured to provide an indication of the remaining runtime to an external display.

7. The device of claim 1 or the system of claim 2, further comprising a power sensor configured to measure power consumed by the battery load.

8. The device of claim 6, wherein the processing circuitry is further configured to calculate an average power consumed by the battery load and calculate a remaining run-time based on the average power consumed by the battery load.

9. The apparatus of claim 1, wherein the expected alert time is defined based on a device specification of a device in which the apparatus is incorporated.

10. The system of claim 2, further comprising a display, and wherein the one or more processors are further configured to provide an indication of remaining runtimes to the display.

11. The system of claim 9, wherein the remaining run-time decrements the expected alert time, and wherein the expected alert time is an amount of time that the one or more processors will provide a low energy alert.

12. The system of claim 2, wherein the remaining battery energy is further decremented by an amount of energy used to power an alarm during the expected alarm time.

13. The system of claim 2, wherein the one or more processors are further configured to calculate an amount of expected energy to provide a low energy alert based on the average load power.

14. The system of claim 2, wherein the one or more processors are further configured to provide an indication of the remaining runtime to an external display.

15. The system of claim 13, wherein the one or more processors are further configured to calculate an average power consumed by the battery load and calculate a remaining run-time based on the average power consumed by the battery load.

16. The system of claim 2, further comprising an alarm to provide an alarm indication during the expected alarm time, wherein the expected alarm time is defined based on a device specification of the system.