CN111239613B - Battery power estimation method and electronic device - Google Patents

Abstract

The invention provides a battery power estimation method and an electronic device. The method comprises the following steps: performing a discharging operation by the battery; detecting a plurality of current values generated by the battery performing the discharging operation via an impedance element within a time range; obtaining a first average current value of the current values; obtaining a numerical distribution state of the current value; and estimating the residual capacity of the battery according to the first average current value, the numerical distribution state and the initial capacity of the battery.

Description

Battery power estimation method and electronic device

technical field

The invention relates to a power management technology, in particular to a battery power estimation method and an electronic device.

Background technique

Generally, the mechanisms used to evaluate the remaining power (also called State of charge, SOC) of batteries in electronic devices include open circuit voltage (open circuit voltage) method, Coulomb counting method, Kalman filter method ) method and neural network (Neural network) method. The open circuit voltage method and the coulomb measurement method are most often used because of the ease of design. However, the estimation accuracy of the open-circuit voltage method will be greatly reduced if the variation of the battery voltage between the battery discharge state and the non-use state is taken into account. The coulometric method is prone to affect the estimation accuracy due to battery aging. The Kalman filter method and the neural network method require high computing power, so the demand for hardware chips is also high, which makes it difficult to implement in practice. In addition, temperature also affects the estimation accuracy of the remaining battery power. If the estimation accuracy of the remaining battery power is low, the operation of the electronic device may be affected. For example, if an electric vehicle is about to run out of power but its control panel shows that there is still 20% of the battery remaining, the driving safety of the electric vehicle may be seriously affected. In addition, other types of electronic devices may also be suddenly powered off due to inaccurate estimation of the remaining battery power, affecting user experience.

SUMMARY OF THE INVENTION

The present invention provides a battery power estimation method and an electronic device, which can improve the accuracy of battery power estimation and avoid sudden power failure of the electronic device.

An embodiment of the present invention provides a battery power estimation method, which includes: performing a discharging operation by a battery; and detecting, within a time range, a plurality of current values generated by the discharging operation performed by the battery through an impedance element, wherein the impedance The element is coupled to the discharge path of the battery; obtains a first average current value of the current value; obtains a numerical distribution state of the current value; The initial charge of the battery estimates the remaining charge of the battery.

An embodiment of the present invention further provides an electronic device, which includes a battery, an impedance element, and a power management circuit. The battery is used to perform a discharge operation to provide power to at least one electronic element of the electronic device. The impedance element is coupled to the discharge path of the battery. The power management circuit is coupled to the battery and the impedance element. Within a time range, the power management circuit detects a plurality of current values generated by the battery performing the discharging operation via the impedance element. The power management circuit obtains a first average current value of the current value and a numerical distribution state of the current value, and the power management circuit obtains the first average current value, the numerical distribution state and the battery according to the first average current value, the numerical distribution state The initial charge estimates the remaining charge of the battery.

Based on the above, after the battery performs the discharge operation, within a time range, a plurality of current values generated by the battery performing the discharge operation can be detected via the impedance element. Next, the first average current value of the current value and the numerical distribution state of the current value can be obtained. According to the first average current value, the value distribution state, and the initial charge of the battery, the remaining charge of the battery can be estimated. Thereby, the estimated remaining power of the battery can be corrected by reflecting the numerical distribution state of the current value, thereby improving the estimation accuracy.

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, the following embodiments are given and described in detail with the accompanying drawings as follows.

Description of drawings

FIG. 1 is a schematic diagram of an electronic device according to an embodiment of the present invention;

FIG. 2 is a flowchart of a method for estimating battery power according to an embodiment of the present invention;

FIG. 3 is a flowchart of a method for estimating battery power according to an embodiment of the present invention.

Description of reference numerals

10: Electronics

11: Battery

12: Impedance element

13: Power management circuit

101: Electronic Components

102: Discharge path

S201～S205, S301～S307: Steps

Detailed ways

FIG. 1 is a schematic diagram of an electronic device according to an embodiment of the present invention. Referring to FIG. 1 , the electronic device 10 may be a smart phone, tablet computer, notebook computer, desktop computer, industrial computer, smart watch, or electric vehicle powered by a battery, and the type of the electronic device 10 is not limited thereto.

The electronic device 10 includes an electronic element 101 , a battery 11 , an impedance element 12 and a power management circuit 13 . The electronic component 101 is coupled to the battery 11 . The electronic components 101 may be various electronic components in the electronic device 10 that need to be powered by the battery 11 for normal operation. Taking a smartphone as an example of the electronic device 10 , the electronic component 101 may include a processor, a storage device, and various input/output devices (eg, a panel, a network interface card, a microphone, and a speaker). Alternatively, taking an electric vehicle as an example of the electronic device 10 , the electronic components 101 may include a drive motor, a control panel, an audio device, a lamp, and the like. In addition, the electronic component 101 may also include other types of electronic components that can receive the power provided by the battery 11 to operate, which is not limited in the present invention. In one embodiment, the electronic component 101 can be regarded as the load of the battery 11 .

The battery 11 is used to perform a discharge operation to provide power to the electronic component 101 . For example, the battery 11 may include a nickel-cadmium (Ni-Cd) battery, a nickel-metal hydride (Ni-MH) battery, a lithium-ion (Li-lon) battery, a lithium-polymer (Li-polymer) battery, and a lead-acid (Sealed) battery of At least one of them, and the type of the battery 11 is not limited thereto. In addition, the number of batteries 11 may be one or more, which is not limited in the present invention.

Impedance element 12 may include electronic elements such as resistors or reactances that may be used to provide impedance. The number of impedance elements 12 may be one or more. The impedance element 12 is coupled to the discharge path 102 of the battery 11 . For example, the discharge path 102 can be used to connect the battery 11 and the electronic component 101 , and the battery 11 can provide power to the electronic component 101 through the discharge path 102 . In one embodiment, the impedance element 12 can be connected to the discharge path 102 in series. However, in another embodiment, the impedance element 12 can also be coupled to the discharge path 102 in parallel or the like, which is not limited in the present invention.

The power management circuit 13 is coupled to the electronic element 101 , the battery 11 and the impedance element 12 . The power management circuit 13 may include one or more chips (or chipsets). For example, the power management circuit 13 may comprise a processor, or other programmable general or special purpose microprocessor, digital signal processor, programmable controller, application specific integrated circuit, programmable logic device or other similar devices or combinations of these devices. In one embodiment, the power management circuit 13 is also referred to as a power management chip (or a power chip).

After the battery 11 starts to perform the discharging operation, within a time range, the power management circuit 13 can detect a plurality of current values generated by the discharging operation of the battery 11 via the impedance element 12 . For example, at a certain point in time within the time range, the power management circuit 13 may detect a current value in response to the impedance provided by the impedance element 12 . At different points in the time range, any two current values detected via the impedance element 12 may be different.

The power management circuit 13 can obtain an average current value (also referred to as a first average current value) of the plurality of current values. For example, the power management circuit 13 may continuously record the N measured current values and divide the sum of the N current values by N to obtain the first average current value. N can be 60 or other positive integer.

The power management circuit 13 can obtain the numerical distribution state of the plurality of current values. This numerical distribution state may reflect the numerical trend of the plurality of current values. For example, the state of the numerical distribution may reflect the state of the numerical distribution of the plurality of current values relative to the first average current value.

In one embodiment, the power management circuit 13 may obtain the number (also referred to as the first number) of current values (also referred to as first current values) that are greater than the first average current value among the plurality of current values. In addition, the power management circuit 13 may obtain the number (also referred to as the second number) of current values (also referred to as second current values) that are less than (or not greater than) the first average current value among the plurality of current values. Then, the power management circuit 13 can obtain the numerical distribution state (or numerical trend) of the plurality of current values according to the first number and the second number. In one embodiment, the numerical distribution state of the plurality of current values may reflect the first number. In one embodiment, the numerical distribution state of the plurality of current values may reflect the second number. In one embodiment, the numerical distribution state of the plurality of current values may reflect the ratio of the first number and the second number. In addition, in another embodiment, the power management circuit 13 may obtain the numerical distribution state of the plurality of current values through other rules, which is not limited in the present invention.

The power management circuit 13 can estimate the remaining power of the battery 11 according to the first average current value, the value distribution state and the initial power of the battery 11 . It should be noted that, in the following embodiments, the power of the battery is measured in coulombs as the evaluation unit. However, in other embodiments, the power of the battery may also be evaluated in other numerical units, which is not limited in the present invention.

In one embodiment, the power management circuit 13 can obtain the initial power of the battery 11 through the open-circuit voltage method. For example, the power management circuit 13 may detect the open circuit voltage value of the battery 11 before the battery 11 starts to perform a discharging operation. For example, the power management circuit 13 may detect the open circuit voltage value of the battery 11 when the battery 11 is not loaded. Then, the power management circuit 13 can obtain the initial power of the battery 11 according to the open-circuit voltage value. For example, the power management circuit 13 can query a management table according to the open circuit voltage value to obtain the amount of electricity corresponding to the open circuit voltage value. For example, the management table can record a plurality of open circuit voltage values and a plurality of corresponding quantities of electricity. The power management circuit 13 can select one of the powers recorded in the management table as the initial power of the battery 11 according to the open-circuit voltage value. Alternatively, in another embodiment, the power management circuit 13 can directly read the remaining power of the battery 11 previously recorded from the non-volatile storage medium (eg, read-only memory or flash memory) of the electronic device 10 as the battery 11 initial power.

In one embodiment, the power management circuit 13 can determine whether the non-volatile storage medium of the electronic device 10 stores the previously recorded remaining power of the battery 11 . If the non-volatile storage medium of the electronic device 10 does not store the previously recorded remaining power of the battery 11 , the power management circuit 13 can obtain the initial power of the battery 11 through the open-circuit voltage method. Alternatively, if the non-volatile storage medium of the electronic device 10 stores the previously recorded remaining power of the battery 11, the power management circuit 13 can directly read the previously recorded remaining power of the battery 11 from the non-volatile storage medium as the battery 11 of the initial power, and can not perform the open circuit voltage method.

In one embodiment, the power management circuit 13 may adjust the first average current value to another average current value (also referred to as a second average current value) according to the numerical distribution state of the plurality of current values. The second average current value is different from the first average current value. For example, the first average current value can be modified or fine-tuned (eg increased or decreased) according to the first number and the second number (eg, the ratio of the first number and the second number) to obtain the second average current value.

In one embodiment, the second average current value may be positively related to the first number. That is, if the total number of current values greater than the first average current value among the plurality of current values is larger (ie, the first number is larger), the determined second average current value may be larger. If the total number of current values smaller than (or not greater than) the first average current value among the plurality of current values is smaller (ie, the second number is larger), the determined second average current value may be smaller.

In one embodiment, the power management circuit 13 may determine a weighting parameter according to the first number, the second number, or the ratio of the first number and the second number. For example, the power management circuit 13 may divide the first number by the second number to obtain the weighting parameter. The power management circuit 13 may multiply the first average current value by the weighting parameter to obtain the second average current value. Then, the power management circuit 13 can estimate the remaining power of the battery 11 according to the second average current value and the initial power of the battery 11 .

In one embodiment, the power management circuit 13 can estimate the remaining power of the battery 11 according to the following equations (1.1) to (1.3).

SOC=SOC ₀ -CC _a (1.1)

CC=I _a ×T (1.3)

In equations (1.1) to (1.3), the parameter I _a represents the second average current value, the parameter T represents the time range for measuring the plurality of current values, and the parameter _In represents the preset rating of the battery 11 The current value, k represents a constant (for example, a value between 1 and 1.28), the parameter CC _a represents the estimated power consumption of the battery 11 within the time range, SOC ₀ represents the initial power of the battery 11, and SOC represents the Estimated remaining charge of battery 11. In one embodiment, the estimated remaining power of the battery 11 takes into account the numerical distribution state of a plurality of current values measured within the time range, so it can be more accurate.

In an embodiment of FIG. 1 , the electronic device 10 further includes a temperature sensor 14 . The temperature sensor 14 may be disposed on the surface of the battery 11 or near the battery 11 . The power management circuit 13 can sense the temperature of the battery 11 via the temperature sensor 14 . Then, the power management circuit 13 may further estimate the remaining power of the battery 11 according to the temperature of the battery 11 .

In one embodiment, the power management circuit 13 can estimate the remaining power of the battery 11 according to equations (1.1), (1.3) and the following equation (2.1).

In equation (2.1), the parameter τ represents the current measured temperature of the battery 11 , the parameter τ _n represents the preset standard temperature of the battery 11 , and α is a constant (eg, 0.01). Compared with Equation (1.2), Equation (2.1) further considers the temperature of the battery 11, so that the estimated remaining capacity of the battery 11 can be more accurate. From another perspective, the estimated remaining capacity of the battery 11 (eg, parameter SOC) may be negatively related to the second average current value (eg, parameter I _a ) and/or the temperature of battery 11 (eg, parameter τ ).

In one embodiment, the power management circuit 13 may determine whether the total number of current values obtained is greater than a predetermined value (eg, 60). If the total number of currently obtained current values is greater than the preset value (for example, 60), the power management circuit 13 can estimate the remaining power of the battery 11 according to the first average current value, the value distribution state and the initial power of the battery 11 . power. For example, the power management circuit 13 can estimate the remaining capacity of the battery 11 according to equations (1.1), (1.2) and (1.3) or equations (1.1), (2.1) and (1.3). However, if the total number of currently obtained current values is not greater than the preset value, the power management circuit 13 can estimate the remaining power of the battery 11 according to the first average current value and the initial power of the battery 11 . In other words, if the total number of currently obtained current values is not greater than the preset value, the power management circuit 13 may not consider the numerical distribution of the current values during the operation of estimating the remaining power of the battery 11 . For example, the power management circuit 13 may estimate the remaining power of the battery 11 according to the following equations (3.1) to (3.3).

SOC=SOC ₀ -CC _b (3.1)

CC=I _b ×T (3.3)

In equations (3.1) to (3.3), the parameter I _b represents the first average current value, and the parameter CC _b represents the estimated power consumption of the battery 11 within the time range. The remaining parameters are the same or similar to those defined above.

In one embodiment, the power management circuit 13 may continuously record P parameters CC _a obtained at P different time points. Each parameter CC _a represents the estimated power consumption of the battery 11 within a certain time frame. For example, P may be 60. The power management circuit 13 can obtain the average value of the P parameters CC _a . Then, the power management circuit 13 can adjust the average value of the P parameters CC _a according to the value distribution state of the P parameters CC _a . For example, the power management circuit 13 may be based on the number (also referred to as the third number) of the P parameters CC _a that is greater than the average value, the parameters of the P parameters CC _a that are less than (or not greater than) the average value The number of (also referred to as the fourth number) and/or the ratio of the third number to the fourth number to adjust the average value of the P parameters CC _a . The adjusted average value of the P parameters CC _a may be positively related to the third number. That is, if the number of parameters greater than the average value among the P parameters CC _a is larger, the power management circuit 13 can increase the average value of the P parameters CC _a . Conversely, if the number of parameters greater than the average value among the P parameters CC _a is smaller, the power management circuit 13 can adjust the average value of the P parameters CC _a to be smaller.

In one embodiment, the average value of the parameter CC _a can be used to estimate the remaining capacity of the battery 11 . For example, the average value of the adjusted parameter CC _a may replace the parameter CC _a in equation (1.1) to obtain the remaining capacity of the battery 11 . Thereby, the remaining power of the battery 11 can be estimated in a gentle manner, preventing the estimated remaining power from changing too much in a short period of time.

FIG. 2 is a flowchart of a method for estimating battery power according to an embodiment of the present invention. Referring to FIG. 2, in step S201, a discharge operation is performed by the battery. In step S202, within a time range, a plurality of current values generated by performing the discharging operation of the battery are detected via an impedance element, wherein the impedance element is coupled to a discharge path of the battery. In step S203, a first average current value of the plurality of current values is obtained. In step S204, the numerical distribution state of the current value is obtained. In step S205, the remaining power of the battery is estimated according to the first average current value, the numerical distribution state and the initial power of the battery.

FIG. 3 is a flowchart of a method for estimating battery power according to an embodiment of the present invention. Referring to FIG. 3, in step S301, a discharge operation is performed by the battery. In step S302, within a time range, a plurality of current values generated by the battery performing the discharging operation are detected via an impedance element, wherein the impedance element is coupled to a discharge path of the battery. In step S303, a first average current value of the plurality of current values is obtained. In step S304, it is determined whether the total of the plurality of current values is greater than a predetermined value. If the total number of the multiple current values is greater than the preset value, in step S305, the numerical distribution state of the current values is obtained. In step S306, the remaining power of the battery is estimated according to the first average current value, the numerical distribution state and the initial power of the battery. In addition, if the total of the plurality of current values is not greater than a preset value, in step S307, the remaining power of the battery is estimated according to the first average current value and the initial power of the battery. That is, in step S307, the remaining power of the battery may be estimated without considering the numerical distribution state of the current value.

However, the steps in FIG. 2 and FIG. 3 have been described in detail above, and will not be repeated here. It should be noted that each step in FIG. 2 and FIG. 3 can be implemented as a plurality of program codes or circuits, which is not limited by the present invention. In addition, the methods of FIG. 2 and FIG. 3 can be used in conjunction with the above exemplary embodiments, and can also be used alone, which is not limited by the present invention.

To sum up, after the battery performs the discharging operation, within a time range, a plurality of current values generated by the discharging operation of the battery can be detected through the impedance element. Next, the first average current value of the current value and the numerical distribution state of the current value can be obtained. According to the first average current value, the value distribution state, and the initial charge of the battery, the remaining charge of the battery can be estimated. Thereby, the estimated remaining battery power can be corrected by reflecting the numerical distribution state of the current value, thereby improving the estimation accuracy and reducing the probability of the electronic device being powered off without warning due to incorrect estimation of the remaining battery power.

Although the present invention has been disclosed above with examples, it is not intended to limit the present invention. Any person skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection shall be subject to what is defined in the claims.

Claims (6)

1. A battery power estimation method, comprising: Detect the open circuit voltage value of the battery; Obtaining the initial power of the battery according to the open-circuit voltage value; performing a discharge operation by the battery; within a time range, detecting a plurality of current values generated by the battery performing the discharging operation via an impedance element, wherein the impedance element is coupled to a discharge path of the battery; obtaining a first average current value of the plurality of current values; obtaining a first number of first current values greater than the first average current value among the plurality of current values; obtaining a second number of second current values of the plurality of current values that are less than the first average current value; The first average current value is adjusted to a second average current value according to the first number and the second number, wherein the second average current value is different from the first average current value, and the first average current value is Two average current values are positively related to the first number; and The remaining power of the battery is estimated according to the second average current value and the initial power of the battery. 2. The battery power estimation method according to claim 1, further comprising: sensing the temperature of the battery via a temperature sensor; and The remaining capacity of the battery is estimated based on the temperature. 3. The battery power estimation method according to claim 1, further comprising: determining whether the total number of the plurality of current values is greater than a preset value; and If the total number of the plurality of current values is not greater than the preset value, the value distribution state of the plurality of current values is not considered and estimated according to the first average current value and the initial charge of the battery the remaining power of the battery. 4. An electronic device comprising: a battery for performing a discharge operation to provide power to at least one electronic element of the electronic device; an impedance element coupled to the discharge path of the battery; and a power management circuit, coupled to the battery and the impedance element, Wherein, before the battery performs the discharging operation, the power management circuit detects the open circuit voltage value of the battery, and obtains the initial power of the battery according to the open circuit voltage value; wherein, within a time range, the power management circuit detects a plurality of current values generated by the battery performing the discharging operation via the impedance element, the power management circuit obtains a first average current value of the plurality of current values, the power management circuit obtains a first number of first current values greater than the first average current value among the plurality of current values, the power management circuit obtains a second number of second current values of the plurality of current values that are smaller than the first average current value, The power management circuit adjusts the first average current value to a second average current value according to the first number and the second number, wherein the second average current value is different from the first average current value , and the second average current value is positively related to the first number, and The power management circuit estimates the remaining power of the battery according to the second average current value and the initial power of the battery. 5. The electronic device of claim 4, further comprising: a temperature sensor for sensing the temperature of the battery, wherein the power management circuit estimates the remaining power of the battery according to the temperature. 6. The electronic device according to claim 4, wherein the power management circuit further determines whether the total of the plurality of current values is greater than a preset value, and If the total number of the plurality of current values is not greater than the preset value, the power management circuit does not consider the numerical distribution state of the plurality of current values, but according to the first average current value and the battery The initial charge estimates the remaining charge of the battery.

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