CN104280686A - Storage battery residual electric quantity detection method - Google Patents

Abstract

The invention discloses a method for detecting the remaining power of a storage battery, which includes the following steps: S1: initialization; S2: judging whether the storage battery is currently in a charging state or a discharging state, and if it is in a charging state, it will detect the amount of electricity in the charging state, and if it is in a discharging state, it will perform discharge State power detection; S3: Dynamically set the sampling frequency, return to step S2. On the premise of not increasing the hardware cost, the present invention makes the battery power detection result very accurate, solves the problem that the user of the charging device cannot accurately grasp the remaining power of the device, and has the ability of automatic calibration of accumulated errors during use, It can automatically adapt to the impact of battery aging and environmental temperature changes on the storage capacity and discharge capacity of the battery, and can automatically adjust the working frequency to adapt to the changing working state of the battery, realizing frequency conversion sampling, and can be widely used in smart phones, tablet computers, portable Computers, electric vehicles and other charging equipment.

Description

A method for detecting the remaining power of a storage battery

technical field

The invention relates to an analog quantity detection method, in particular to a storage battery remaining power detection method.

Background technique

In the charging equipment, the analog quantity collector is usually used to obtain the voltage between the plates of the battery, and the percentage of the remaining power of the battery is obtained indirectly from the mapping relationship between the percentage of the remaining power of the battery and the voltage between the plates of the battery.

However, as shown in Figure 1, the percentage of remaining battery capacity and the voltage between the plates of the battery often only show an approximate linear correlation in the middle section of the function graph, but when the charge is low or high, the voltage between the plates of the battery Decreases rapidly as the percentage of remaining battery charge decreases. As a result, when the charging device is just fully charged or the remaining power is low, the percentage value of the remaining power displayed in the charging device drops rapidly, so that the user cannot accurately grasp the remaining power of the charging device.

Some charging equipment, on the basis of the above method for detecting the percentage of remaining battery power, correct the mapping relationship between the percentage of remaining battery power and the voltage between the battery plates, so that when the battery power is low and the power is high, the battery plate The inter-voltage can be more accurately mapped to the percentage of remaining power of the battery, so that the value of the percentage of remaining power of the charging device can be displayed more accurately. However, when the operating power of the charging equipment suddenly increases, due to the existence of the polarization phenomenon of the battery plates, the voltage between the battery plates drops significantly, so that the percentage of remaining battery power detected by the charging equipment is obviously low. This makes the charging equipment when the power is low, once it suddenly enters a higher power working state, it will immediately mistakenly think that the battery power is too low, causing the charging equipment to automatically shut down abnormally.

When a charging device has a lot of remaining power, it will not automatically shut down after suddenly entering a high-power working state, but the value of the remaining power percentage displayed by the charging device will decrease rapidly. However, when the charging device returns to the working state of low power again, due to the weakening of the polarization of the battery plates, the voltage between the battery plates will rise, and the detection result of the remaining battery power will rise, resulting in the percentage value of the remaining power displayed by the charging device. Bouncing back errors.

No matter which of the above methods for detecting the remaining capacity of the battery, the method of indirectly obtaining the percentage of the remaining capacity of the battery through the voltage between the plates of the battery is adopted. However, due to the non-linear correlation between the percentage of remaining battery power and the voltage between the battery plates, and the existence of the polarization phenomenon of the battery plates, the method of indirectly obtaining the percentage of the remaining power of the battery through the voltage between the battery plates cannot accurately detect the battery. The percentage of battery remaining.

Contents of the invention

The purpose of the present invention is to overcome the disadvantages in the prior art that the user cannot accurately grasp the remaining power of the charging device, and provide a device with very accurate detection results that can avoid rebounding errors in the percentage of remaining power displayed by the charging device. The method for detecting the remaining power of the storage battery can ensure the accuracy of the detection result of the percentage of the remaining power while taking into account the power saving characteristics.

The object of the present invention is achieved through the following technical solutions: a method for detecting the remaining power of a storage battery, comprising the following steps:

S1: Initialize, initialize and set the parameters to be used;

S2: Determine whether the battery is currently in a charging state or a discharging state, if it is in a charging state, go to step S3, if it is in a discharging state, go to step S4;

S3: Carry out battery detection of the state of charge;

S4: Carry out electric quantity detection in discharge state;

S5: Dynamically set the sampling frequency, return to step S2.

Further, the initialization of step S1 includes the following sub-steps:

S11: Set the current remaining power percentage of the battery as q, and q is the percentage of the current remaining power of the battery to the maximum power of the battery, which is the final detection variable;

S12: Set the current remaining power of the battery as Q, and initialize Q, so that Q=0;

S13: set the maximum battery capacity as Q _max ;

S14: Set the charging state sampling period as T _i , and the discharging state sampling period as T _o ;

S15: Set the upper limit of battery voltage as U _max , and the lower limit of battery voltage as U _min ;

S16: Set the electric power series W, and the upper limit of the number of items is N;

S17: Set the battery charging/discharging status flag as Flag (a value of 0 indicates a charging status, and a value of 1 indicates a discharging status).

Further, the storage battery theoretically has three states, which are charging state, discharging state and idle state, and the idle state of the battery is regarded as a special discharge state in which the discharge current is 0 in the discharging state, so the storage battery only has There are two states of charging and discharging, either one or the other.

Further, the detection of the state of charge in the step S3 includes the following sub-steps:

S31: Determine whether Flag is equal to 1, if Flag==1, set Flag=0 and clear the sequence W;

S32: Obtain the charging current value I _i ;

S33: Accumulate Q by I _i *T _i , that is, Q=Q+I _i *T _i ;

S34: Obtain the charging voltage value U _i ;

S35: Let q=f(U _i ), where f(U _i ) is the function value of the percentage of remaining power of the battery with respect to the voltage between the plates of the battery;

S36: Determine whether U _i is equal to U _max , if U _i == U _max , set Q _max =Q;

S37: Wait for the charging state sampling period T _i ;

S38: Add the product of U _i and I _i to the sequence W.

Further, the detection of the discharge state electricity in the step S4 includes the following sub-steps:

S41: Determine whether Flag is equal to 0, if Flag==0, set Flag=1 and clear the sequence W;

S42: Obtain the discharge current I _o ;

S43: Judging whether I _o is less than C*Q _max , if I _o <C*Q _max , obtain the discharge voltage value U _o ; otherwise, subtract I _o *T _o from Q, that is, Q=QI _o *T _o , and then proceed The operation of step S46;

S44: Judging whether U _o is equal to U _min , if U _o == U _min , set Q=0 and q=0, and then proceed to step S47;

S45: Judging whether q is greater than the percentage of remaining power of the battery with respect to the function value f(U _o ) of the voltage between the battery plates, if q>f(U _o ), then set q=f(U _o ) and Q=q*Q _max , then carry out the operation of step S47, otherwise directly carry out the operation of step S47;

S46: judge whether Q/Q _max is less than q, if Q/Q _max <q then make q=Q/Q _max ;

S47: waiting for the discharge state sampling period T _o ;

S48: Add the product of U _o and I _o to the sequence W.

Further, dynamically setting the sampling frequency in the described S5 includes the following steps:

S51: Calculate the standard deviation α of the sequence W;

S52: judge whether Flag is equal to 0, if Flag==0, proceed to step S53, otherwise proceed to step S54;

S53: Make T _i equal to the function value T _in (α) of the charging state sampling period with respect to the number W standard deviation α;

S54: Let T _o be equal to the function value T _out (α) of the discharge state sampling period with respect to the standard deviation α of the sequence W.

The beneficial effects of the present invention are:

1. On the premise of not increasing the hardware cost, the detection result of the battery power becomes very accurate, which solves the problem that the user of the charging device cannot accurately grasp the remaining power of the device. When it is larger, the phenomenon that the charging equipment mistakenly thinks that the power is exhausted due to the polarization of the battery plate will automatically shut down abnormally, and the error of the percentage value of the remaining power displayed by the charging equipment will be avoided;

2. The detection method of the present invention has the ability of automatic calibration of accumulated errors during use, can automatically adapt to the influence of battery aging and environmental temperature changes on the storage capacity and discharge capacity of the battery, and can automatically adjust the working frequency to adapt to the changes in the battery. In the working state, the frequency conversion sampling is realized, and the power saving characteristics of the method are taken into account on the premise of ensuring the accuracy of the detection result of the percentage of remaining battery power;

3. It is generally applicable to various types and models of charging equipment. On the premise of not increasing the hardware cost, it realizes the accurate detection function of the remaining battery power in the charging equipment with pure software algorithm, and is not limited by the operating system. It can be widely used in charging equipment such as smartphones, tablet computers, portable computers, and electric vehicles.

Description of drawings

Fig. 1 is a diagram showing the relationship between the remaining power percentage of a lithium-ion battery and the voltage between the pole plates;

Fig. 2 is the detection method flowchart of the present invention;

Fig. 3 is the flowchart of initialization step in the detection method of the present invention;

Fig. 4 is the flow chart of the detection step of state of charge electric quantity in the detection method of the present invention;

Fig. 5 is the flow chart of the electric quantity detection step of discharge state in the detection method of the present invention;

Fig. 6 is a flowchart of the step of dynamically setting the sampling frequency in the detection method of the present invention.

Detailed ways

The technical solution of the present invention will be further described below in conjunction with the accompanying drawings, but the content protected by the present invention is not limited to the following description.

As shown in Figure 2, a method for detecting the remaining power of a storage battery includes the following steps:

S1: Initialize, initialize and set the parameters to be used;

S2: Determine whether the battery is currently in a charging state or a discharging state, if it is in a charging state, go to step S3, if it is in a discharging state, go to step S4;

S3: Carry out battery detection of charging state;

S4: Carry out electric quantity detection in discharge state;

S5: Dynamically set the sampling frequency, return to step S2.

When the battery remaining power detection starts, first define and initially assign the parameters that need to be used in the method, and then formally enter the loop structure of the method to obtain the percentage of the remaining battery power in real time, and then realize the remaining power of the battery inside the charging device The accurate detection of percentage, as shown in Figure 3, the initialization of described step S1 comprises the following sub-steps:

S11: Set the percentage of the current remaining power of the battery as q:

q is the percentage of the current remaining power of the battery to the maximum power of the battery, which is the final detection variable; q is a percentage, between 0 and 100%, which indicates the percentage of the current remaining power in the battery to the maximum power of the battery, that is, usually in The "remaining battery percentage" displayed on smart mobile terminals such as smartphones and tablets. Since the power storage capacity and discharge capacity of the battery are affected by many factors such as battery aging and environmental temperature changes, the purpose of this embodiment is to detect the value of q, that is, q is the ultimate goal of this "battery remaining power detection method" parameter, the existence of all other parameters is to ensure the accuracy of the battery remaining power percentage q;

S12: Set the current remaining power of the battery as Q, and initialize Q, so that Q=0:

Q is a decimal, it is used to represent the current remaining power in the battery, its unit is the product of the current unit and the time unit, usually milliampere-hour (mA.H) or ampere-hour (A.H), the value of Q is initialized is 0, indicating that the power of the battery is 0 when it is just activated;

S13: Set the maximum battery capacity as Q _max :

Q _max is a decimal number, which is used to represent the maximum amount of electricity that the battery can store, that is, the value of Q _max is the amount of electricity when the battery is fully charged, and its unit is the product of the current unit and the time unit, usually milliamp hours ( mA.H) or ampere-hour (AH), the value of Q _max is updated and calibrated when each charge is completed, thereby realizing automatic adaptation to the impact of battery aging and ambient temperature changes on battery storage capacity and discharge capacity;

S14: Set the charging state sampling period as T _i , and the discharging state sampling period as T _o :

T _i is a decimal number, it is used to indicate the size of the sampling cycle when the storage battery is charged, according to the relationship between frequency and cycle f = 1/T, when the value of T _i is smaller, the sampling frequency of the charging state is higher, when T _i The larger the value of , the lower the sampling frequency of the charging state; T _o is a decimal, which is used to represent the size of the sampling period when the battery is in the discharge state. When the value of T _o is smaller, the sampling frequency of the discharging state is higher. When T _o The larger the value of , the lower the sampling frequency of the discharge state;

It should be noted that the higher the sampling frequency, the higher the accuracy, and the lower the sampling frequency, the lower the accuracy. However, the higher the accuracy, the corresponding increase in the amount of calculation will lead to a certain increase in power consumption. Therefore, it is necessary to weigh the pros and cons in the specific implementation and construct a suitable sampling period function. In addition, when assigning initial values to T _i and T _o , it is sufficient to assign a smaller value that is not 0 according to actual needs, because the values of T _i and T _o will be automatically adjusted in the subsequent execution process .

S15: Set the upper limit of battery voltage as U _max , and the lower limit of battery voltage as U _min :

U _max is a decimal number, which is used to represent the upper limit of the voltage between the battery plates, and its unit is usually volts (V) or millivolts (mV). When the battery is in a charging state, when the voltage between the battery plates reaches U _max , that is Indicates that the charging of the battery is complete. It should be noted that the upper voltage limit of different types of batteries often varies greatly. Therefore, in practical applications, it is necessary to set a corresponding value for U _max according to the type of battery, for example, the U _max value of a lithium-ion battery is 4.2;

U _min is a decimal, it is used to indicate the lower limit of the voltage between the battery plates, its unit is volts (V) or millivolts (mV), when the open circuit voltage between the battery plates is less than or equal to U _min , it means that the battery power has been run out. It should be noted that the lower voltage limit of different types of batteries often varies greatly. Therefore, in practical applications, it is necessary to set a corresponding value for U _min according to the type of battery, for example, the value of U _min for a lithium-ion battery is 3.

S16: Assume that the electric power series W has an upper limit of N items:

Each item in W is a decimal, indicating the charging or discharging power value of the battery at a certain moment. In order to ensure the stability of the system and save the memory space of the charging device, the power detection of the charging state and the power detection of the discharging state are shared. W sequence, the specific implementation method is described in detail in the steps of "detection of electric quantity in charge state" and "detection of electric quantity in discharge state". It should be noted that limiting the number of items in the sequence W to less than N is to prevent the method from occupying the memory space of the charging device endlessly during execution, and also to ensure the response rate of the method to the working state of the battery. The larger the value of N, the more stable the system operation, but the response rate of the method to the working state of the battery will be correspondingly slower. On the contrary, the smaller the value of N, the faster the response rate of the method to the working state of the battery, but the stability of the system operation will be reduced. Correspondingly weakened. Therefore, in practical applications, it is necessary to set an appropriate value for N according to actual needs;

S17: Set the battery charging/discharging status flag as Flag:

Flag is a Boolean variable. When its value is false, it means that the battery is in a state of charging. When its value is true, it means that the battery is in a state of discharge. (In this article, 0 means false and 1 means true)

After the initialization work is completed, it is immediately judged whether the storage battery is currently in a charging state or a discharging state, and different detection methods are used in the charging state and discharging state to detect the remaining power of the storage battery. The storage battery has three states in theory, which are charging state, discharging state and idle state respectively. In this embodiment, the idle state of the storage battery is regarded as a special discharge state in which the discharge current is 0 in the discharging state. Therefore, the storage battery There are only two states of charging and discharging, either one or the other.

The method for detecting the charge state electricity in step S3 described in this embodiment is as follows: when the battery is in the charging state, through the mapping relationship between the percentage of remaining power of the battery and the voltage between the plates of the battery, while obtaining the percentage of remaining power of the battery, by The charging current of the battery is integrated with respect to time, and the remaining power of the battery is counted. When the charging of the battery is completed, the maximum power value of the battery is updated, thereby realizing the automatic calibration of the cumulative error generated during the detection of the remaining battery power. The specific process is shown in Figure 4, including the following sub-steps:

S31: Determine whether Flag is equal to 1, if Flag==1, set Flag=0 and clear the sequence W;

S32: Obtain the charging current value I _i ;

S33: Accumulate Q by I _i *T _i , that is, Q=Q+I _i *T _i ;

S34: Obtain the charging voltage value U _i ;

S35: Let q=f(U _i ), where f(U _i ) is the function value of the percentage of remaining power of the battery with respect to the voltage between the plates of the battery;

S36: Determine whether U _i is equal to U _max , if U _i == U _max , set Q _max =Q;

S37: Wait for the charging state sampling period T _i ;

S38: Add the product of U _i and I _i to the sequence W.

The purpose of step S31 is: when the storage battery enters the charging state from the discharge state, the variable Flag representing the storage battery state is set to 0, indicating that the storage battery has entered the charging state; when the storage battery enters the charging state from the discharging state, the existing All discharge power values are cleared, and are used to store charging power values in the next work of "charging state power detection".

The purpose of steps S32 and S33 is to record the amount of electricity charged into the battery during the charging state sampling period T _i .

The purpose of steps S34 and S35 is to indirectly obtain the percentage of remaining battery power q through the mapping relationship between the percentage of remaining power of the battery and the voltage between the battery plates, f(x) is a function of the percentage of remaining power of the battery q on the voltage between the plates of the battery, In practical applications, an appropriate f(x) function analytical formula can be constructed according to the type and performance of the battery, and the remaining charge percentage q=f(U _i ) of the battery can be obtained by bringing the charging voltage U _i into it.

The purpose of step S36 is: when the voltage between the battery plates reaches the upper limit U _max , it means that the charging of the battery is completed. At this time, the value of the remaining battery capacity Q is assigned to Q _max , that is, the value of Q _max is updated, and the adjustment of Q _max is completed at the same time. calibration.

The purpose of step S37 is to control the sampling frequency of the state of charge. It should be noted that, in order to ensure the accuracy of the percentage q of the remaining power of the battery detected in this method, when waiting for the sampling period T _i of the state of charge, it is necessary to consider The time consumed for logical judgment and numerical calculation in the step of "power detection" means that the time interval between the two sampling actions before and after must be guaranteed to be accurate T _i .

The purpose of step S38 is: to multiply the voltage U _i between the battery plates obtained this time by the charging current I _i to obtain the charging power, and add the value of the charging power to W. The reason for this will be explained in detail in the "Dynamically Setting the Sampling Frequency" step. It should be noted that when the number of items in the sequence W is less than N, when adding a new charging power value, you only need to add the new charging power value as the last item of the current sequence to the end of the sequence W. However, when the number of items in the sequence W has reached N, it is necessary to delete the first item of the current sequence W before adding a new charging power value, and add the new charging power value as the Nth item to the sequence W, so as to maintain the sequence The number of items in W does not exceed N.

The method for detecting the electric quantity in the discharge state in step S4 described in this embodiment is: when the battery is in the discharge state, when the discharge current is less than a certain threshold value, the remaining electric quantity of the battery is obtained through the mapping relationship between the percentage of the remaining electric quantity of the battery and the voltage between the plates of the battery Percentage; when the discharge current is greater than or equal to this threshold, the percentage of remaining battery power is obtained by integrating the battery discharge current with respect to time, and the two methods calibrate each other for errors. That is to say, on the one hand, the error generated by obtaining the percentage of remaining power of the battery through f(x) can be calibrated by the process of integrating the discharge current of the battery with respect to time. On the other hand, the error generated by obtaining the percentage of remaining battery power by integrating the discharge current of the battery with respect to time can be calibrated by the process of obtaining the percentage of remaining battery power through f(x). The specific process is shown in Figure 5, including the following sub-steps:

S41: Determine whether Flag is equal to 0, if Flag==0, set Flag=1 and clear the sequence W;

S42: Obtain the discharge current I _o ;

S43: Judging whether I _o is less than C*Q _max , if I _o <C*Q _max , obtain the discharge voltage value U _o ; otherwise, subtract I _o *T _o from Q, that is, Q=QI _o *T _o , and then proceed The operation of step S46;

S44: Judging whether U _o is equal to U _min , if U _o == U _min , set Q=0 and q=0, and then proceed to step S47;

S45: Judging whether q is greater than the function value f(U _o ) of the battery remaining power percentage with respect to the voltage between the battery plates, if

q>f(U _o ), then let q=f(U _o ) and Q=q*Q _max , then proceed to step S47, otherwise directly proceed to step S47

operation;

S46: judge whether Q/Q _max is less than q, if Q/Q _max <q then make q=Q/Q _max ;

S47: waiting for the discharge state sampling period T _o ;

S48: Add the product of U _o and I _o to the sequence W.

The purpose of step S41 is: when the storage battery enters the discharge state from the charging state, set the variable Flag representing the storage battery state to 1, indicating that the storage battery has entered the discharging state; when the storage battery enters the discharging state from the charging state, set the existing All the charging power values are cleared, and are used to store the discharging power values in the next work of "discharging state power detection".

The purpose of steps S42 and S43 is to judge whether the current discharge current I _o of the battery is small enough, because when the battery is discharging, the greater the discharge current I _o , the greater the polarization of the battery plates, resulting in a lower voltage between the battery plates . Therefore, only when the discharge current I _o of the battery is small enough, the percentage of remaining battery power q can be obtained indirectly through the mapping relationship between the percentage of remaining battery power and the voltage between the battery plates. However, when the battery discharge current I _o is large, the polarization of the battery plates is large, and the voltage between the battery plates is obviously low. At this time, it is necessary to integrate the battery discharge current I _o with respect to time to obtain the battery discharge current I o Cycle T _o How much electric energy is output during this period, and then calculate the value of the remaining power percentage q. When judging whether the discharge current I _o of the battery is small enough, the maximum battery capacity Q _max multiplied by a factor C is used as the critical value. The value of C can be selected according to the type of battery and the performance of the battery in practical applications. "Discharge C rate". When the battery discharge current I _o is less than the critical value, it is judged that the discharge current I _o is small enough, and when the battery discharge current I _o is greater than or equal to the critical value, it is judged that the discharge current I _o is large.

The purpose of step S44 is: when it is found that the voltage between the battery plates reaches the lower limit _Umin , set the battery power Q to 0, and at the same time set the battery remaining power percentage q to 0, that is, update the values of Q and q, and complete Calibration of Q and q.

The purpose of step S45 is: when the discharge current I _o is sufficiently small, the percentage of remaining battery power q can be obtained indirectly through the mapping relationship between the percentage of remaining battery power and the voltage between the battery plates. f(x) is the function of the battery remaining capacity percentage q on the voltage between the battery plates. In practical applications, an appropriate f(x) function analysis formula can be constructed according to the battery type and battery performance, and the discharge voltage U _o can be brought into Obtain the remaining power percentage of the storage battery q=f(U _o ), and at the same time set Q=q*Q _max to calibrate the value of Q. In order to avoid the rebound error of the remaining battery power value, before assigning a value to q, first judge whether q is greater than f(U _o ), if q is greater than f(U _o ), then set q=f(U _o ), otherwise not operate.

The purpose of step S46 is: when the discharge current I _o is relatively large, by integrating the discharge current I _o with respect to time, it is possible to obtain how much power the storage battery has output during the period T _o of the discharge state sampling period, and by converting the original Subtract the consumed electricity from the electricity to get the value of the new battery remaining electricity percentage q. In order to avoid the rebound error of the remaining battery power value, before assigning q, first judge whether Q/Q _max is less than q, if Q/Q _max is less than q, set q=Q/Q _max , otherwise do not operate.

The purpose of step S47 is to control the sampling frequency of the discharge state. It should be noted that, in order to ensure the accuracy of the percentage q of remaining battery power detected in this embodiment, when waiting for the discharge state sampling period T _o , it is necessary to consider making logical judgments and The time consumed by the numerical operation, that is, it is necessary to ensure that the time interval between the two sampling actions is accurate T _o .

The purpose of step S48 is: to multiply the voltage U _o between the plates of the battery obtained this time by the discharge current I _o to obtain the discharge power, and add the value of the discharge power to W. The reason for this will be explained in detail in the "Dynamically Setting the Sampling Frequency" step. It should be noted that when the number of items in the sequence W is less than N, when adding a new discharge power value, you only need to add the new discharge power value as the last item of the current sequence to the end of the sequence W. However, when the number of items in the sequence W has reached N, it is necessary to delete the first item of the current sequence W before adding a new discharge power value, and add the new discharge power value as the Nth item to the sequence W, so as to maintain the sequence The number of items in W does not exceed N.

As shown in Figure 6, dynamically setting the sampling frequency in S5 described in this embodiment includes the following steps:

S51: Calculate the standard deviation α of the sequence W;

S52: judge whether Flag is equal to 0, if Flag==0, proceed to step S53, otherwise proceed to step S54;

S53: Make T _i equal to the function value T _in (α) of the charging state sampling period with respect to the standard deviation α of the sequence W;

S54: Let T _o be equal to the function value T _out (α) of the discharge state sampling period with respect to the standard deviation α of the sequence W.

The purpose of step S51 is: by calculating the standard deviation α of the sequence W, to obtain the stability of the charging power or discharging power of the battery in the charging state or discharging state represented by α. The larger the value of α, the worse the stability, and the smaller the value of α, the stronger the stability.

The purpose of step S52 is to determine whether the battery is currently in a charging state or a discharging state by judging the value of the flag bit of the battery state, and to set corresponding sampling periods for the electric quantity detection in the charging state and the electric quantity detection in the discharging state.

The purpose of step S53 is: in step S51, an α representing the stability of the charging power has been obtained. The larger the value of α, the worse the stability of the charging power, and the charging state sampling frequency T _i should be increased accordingly to adapt to unstable conditions. charging power. The smaller the α value, the stronger the stability of the charging power, which can reduce the charging state sampling frequency T _i correspondingly, reduce the workload, and reduce the power consumption of the method. It should be noted that the higher the sampling frequency, the higher the accuracy, and the power consumption will also increase to a certain extent. The lower the sampling frequency, the lower the accuracy, and the power consumption will also be reduced to a certain extent. Therefore, in practical applications, To balance the pros and cons, a suitable function T _in (α) of the charging state sampling period T _i with respect to the standard deviation α of the sequence W can be constructed as required.

The purpose of step S54 is: in step S51, an α indicating the stability of the discharge power has been obtained. The larger the value of α, the worse the stability of the discharge power, and the sampling frequency T _o of the discharge state should be increased accordingly to adapt to the unstable discharge power. The smaller the α value, the stronger the stability of the discharge power, which can reduce the sampling frequency T _o of the discharge state accordingly, reduce the workload, and reduce the power consumption of the method. It should be noted that the higher the sampling frequency, the higher the accuracy, and at the same time, the power consumption will increase to a certain extent. The lower the sampling frequency, the lower the accuracy, and at the same time, the power consumption will also be reduced to a certain extent. Therefore, in practical applications, the advantages and disadvantages need to be weighed, and a function T _out (α) of a suitable discharge state sampling period T _o with respect to the standard deviation α of the sequence W can be constructed as required.

All the above steps logically form a loop structure to obtain the percentage of remaining power of the battery in real time, and then realize accurate detection of the percentage of remaining power of the battery inside the charging device.

The realization of the "accumulated error automatic calibration" function of the present invention enables the detection method of the present invention to automatically adapt to the effects of accumulator aging and environmental temperature changes on the storage capacity and discharge capacity of the accumulator. The electric quantity detection process of the present invention does not require manual participation at all, and the storage battery can learn the parameter values required in the method independently only after a complete charging/discharging process.

Regardless of whether the storage battery is in a charging state or a discharging state, the sampling frequency of the method for detecting the remaining battery capacity of the present invention can dynamically adapt to the current working state of the storage battery, thereby realizing dynamic frequency conversion sampling. Therefore, this method is generally applicable to various types and types of storage batteries, that is, the "method for detecting the remaining power of the storage battery" has universal applicability. The smart mobile terminal itself has the ability to collect analog quantities and the necessary computing power, so there is no need to add any hardware to implement this method. On the premise of not increasing the hardware cost, the remaining power of the internal battery of the charging device is realized with a pure software algorithm. Accurate detection function. If in practical application, this method needs to be implemented in a charging device that does not have analog quantity acquisition capability and computing capability, then an analog quantity collector and a suitable computing chip.

Those skilled in the art will appreciate that the embodiments described here are to help readers understand the principles of the present invention, and it should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical revelations disclosed in the present invention without departing from the essence of the present invention, and these modifications and combinations are still within the protection scope of the present invention.

Claims (6)

1. A method for detecting battery remaining capacity, characterized in that: comprising the following steps: S1: Initialize, initialize and set the parameters to be used; S2: Determine whether the battery is currently in a charging state or a discharging state, if it is in a charging state, go to step S3, if it is in a discharging state, go to step S4; S3: Carry out battery detection of the state of charge; S4: Carry out electric quantity detection in discharge state; S5: Dynamically set the sampling frequency, return to step S2. 2. The method for detecting remaining battery power according to claim 1, characterized in that: the initialization of step S1 includes the following sub-steps: S11: Set the current remaining power percentage of the battery as q, and q is the percentage of the current remaining power of the battery to the maximum power of the battery, which is the final detection variable; S12: Set the current remaining power of the battery as Q, and initialize Q, so that Q=0; S13: set the maximum battery capacity as Q _max ; S14: Set the charging state sampling period as T _i , and the discharging state sampling period as T _o ; S15: Set the upper limit of battery voltage as U _max , and the lower limit of battery voltage as U _min ; S16: Set the electric power series W, and the upper limit of the number of items is N; S17: Set the battery charging/discharging status flag as Flag (a value of 0 indicates a charging status, and a value of 1 indicates a discharging status). 3. The method for detecting the remaining power of the storage battery according to claim 1, characterized in that: the storage battery has three states in theory, which are respectively the charging state, the discharging state and the idle state, and the idle state of the storage battery is regarded as the discharging state. In the state, there is a special discharge state in which the discharge current is 0, so the battery only has two states of charging and discharging, either one or the other. 4. The method for detecting the remaining power of the storage battery according to claim 2, wherein the detection of the state of charge power in the step S3 includes the following sub-steps: S31: Determine whether Flag is equal to 1, if Flag==1, set Flag=0 and clear the sequence W; S32: Obtain the charging current value I _i ; S33: Accumulate Q by I _i *T _i , that is, Q=Q+I _i *T _i ; S34: Obtain the charging voltage value U _i ; S35: Let q=f(U _i ), where f(U _i ) is the function value of the percentage of remaining power of the battery with respect to the voltage between the plates of the battery; S36: Determine whether U _i is equal to U _max , if U _i == U _max , set Q _max =Q; S37: Wait for the charging state sampling period T _i ; S38: Add the product of U _i and I _i to the sequence W. 5. The method for detecting the remaining power of the storage battery according to claim 2, characterized in that: the detection of the discharge state power in the step S4 includes the following sub-steps: S41: Determine whether Flag is equal to 0, if Flag==0, set Flag=1 and clear the sequence W; S42: Obtain the discharge current I _o ; S43: Judging whether I _o is less than C*Q _max , if I _o <C*Q _max , obtain the discharge voltage value U _o ; otherwise, subtract I _o *T _o from Q, that is, Q=QI _o *T _o , and then proceed The operation of step S46; S44: Judging whether U _o is equal to U _min , if U _o == U _min , set Q=0 and q=0, and then proceed to step S47; S45: Judging whether q is greater than the percentage of remaining power of the battery with respect to the function value f(U _o ) of the voltage between the battery plates, if q>f(U _o ), then set q=f(U _o ) and Q=q*Q _max , then carry out the operation of step S47, otherwise directly carry out the operation of step S47; S46: judge whether Q/Q _max is less than q, if Q/Q _max <q then make q=Q/Q _max ; S47: waiting for the discharge state sampling period T _o ; S48: Add the product of U _o and I _o to the sequence W. 6. The method for detecting the remaining battery power according to claim 2, characterized in that: dynamically setting the sampling frequency in the step S5 comprises the following steps: S51: Calculate the standard deviation α of the sequence W; S52: judge whether Flag is equal to 0, if Flag==0, proceed to step S53, otherwise proceed to step S54; S53: Make T _i equal to the function value T _in (α) of the charging state sampling period with respect to the standard deviation α of the sequence W; S54: Let T _o be equal to the function value T _out (α) of the discharge state sampling period with respect to the standard deviation α of the sequence W.