A charging control method and system for a battery charger

Abstract

The present invention relates to the technical field of battery charging control, and proposes a charging control method and system for a battery charger, including: obtaining a current sequence, a voltage sequence and a temperature sequence; obtaining a current correction oscillation coefficient of the current sequence; obtaining a charging current correction degree of the current sequence; obtaining an abnormal temperature variation index and an abnormal voltage variation index according to the temperature sequence and the voltage sequence, obtaining a first correlation degree and a second correlation degree, and then obtaining an external influencing factor of the current integral gain, obtaining a current integral gain coefficient according to an internal influencing factor of the integral gain of the current sequence and an external influencing factor of the current integral gain, obtaining a voltage integral gain coefficient according to the voltage sequence, performing constant current regulation according to the current integral gain coefficient, and performing constant voltage regulation according to the voltage integral gain coefficient. The present invention solves the problem of poor effect of regulating the charging voltage and charging current of a battery charger.

Description

Technical Field

[0001] The present invention relates to the technical field of battery charging control, and in particular to a charging control method and system for a battery charger. Background Art

[0002] A battery charger is a device that charges rechargeable batteries. It is widely used in electric vehicles, power tools, laptops, and other electronic and electrical equipment that require batteries. Battery chargers can maintain the normal operation of equipment and increase the life of batteries. At the same time, they save the cost of replacing batteries and reduce environmental pollution. However, different types of batteries have different requirements for charging current and voltage. If the battery charger is not charged and controlled, it may cause the battery to be overcharged, thereby shortening the battery life or causing battery leakage, which in turn may cause safety issues such as battery explosion. Therefore, in the process of using a battery charger to charge a battery, it is necessary to regulate the charging voltage and charging current of the battery charger to ensure normal and stable charging of the battery.

[0003] PI control algorithm is a common control algorithm for regulating the charging voltage and charging current of battery chargers. It has the advantages of small steady-state error, fast system response, and stable regulation. It is widely used in automatic control systems. The integral gain coefficient in the PI control algorithm directly affects the control effect and stability. Since the control object and environment in the actual control system will change all the time, it is necessary to dynamically adjust the integral gain coefficient. However, the traditional PI control algorithm uses a large number of experiments or simulations to select the integral gain coefficient through trial and error. The parameter selection is difficult and the parameters cannot be adjusted in real time according to the specific situation. Fine adjustment makes it impossible for the PI control algorithm to achieve good control effect and good stability. Summary of the invention

[0004] The present invention provides a charging control method and system for a battery charger to solve the problem of poor effect of regulating the charging voltage and charging current of the battery charger. The technical solution adopted is as follows:

[0005] In a first aspect, an embodiment of the present invention provides a charging control method for a battery charger, the method comprising the following steps:

[0006] Collect the charging current, charging voltage and battery surface temperature when the battery charger is charging the battery, obtain current data, temperature data and voltage data, and obtain current sequence, voltage sequence and temperature sequence;

[0007] Obtain a current correction stability coefficient of the current sequence according to the current sequence, obtain a first slope and a current oscillation degree data sequence, and then obtain a current correction oscillation coefficient of the current sequence, and obtain a current correction oscillation coefficient of the current sequence according to the current correction stability coefficient and the current correction oscillation coefficient;

[0008] The ratio of the current correction stability coefficient of the current sequence to the current correction oscillation coefficient is recorded as the current correction stability index of the current sequence;

[0009] Obtaining a first front mean value and a first rear mean value according to current data contained in the current sequence, and obtaining a charging current correction degree of the current sequence according to the first front mean value, the first rear mean value and the current sequence;

[0010] The difference between the current data contained in the current sequence and the mean of all the current data contained in the current sequence is recorded as the first difference of the current data; the mean of the first difference of the first second preset threshold current data contained in the current sequence is recorded as the first mean; the mean of the first difference of the last second preset threshold current data contained in the current sequence is recorded as the last first mean;

[0011] Obtain an abnormal temperature variation index and an abnormal voltage variation index according to the temperature sequence and the voltage sequence, obtain a first correlation degree and a second correlation degree, obtain an external influencing factor of the current integral gain according to the abnormal temperature variation index, the abnormal voltage variation index, the first correlation degree and the second correlation degree, obtain a current integral gain coefficient according to the integral gain internal influencing factor of the current sequence and the external influencing factor of the current integral gain, obtain a voltage integral gain coefficient according to the voltage sequence, perform constant current control according to the current integral gain coefficient, and perform constant voltage control according to the voltage integral gain coefficient;

[0012] Among them, the sum of the external influencing factor of the current integral gain and the third parameter adjustment constant is recorded as the fourth sum value; the normalized value of the ratio of the internal influencing factor of the integral gain of the current sequence to the fourth sum value is recorded as the first normalized value; the product of the first normalized value and the first constant is summed with the second constant, and the result of the summation is recorded as the current integral gain coefficient.

[0013] Further, the method for obtaining the current correction stability coefficient of the current sequence according to the current sequence is:

[0014] Obtain trend item data series and season item data series according to the current series;

[0015] Record the data included in the trend item data sequence as trend item current, and record the data included in the season item data sequence as season item current;

[0016] Using the least square method for the last first preset threshold trend item current in the trend item data sequence, the trend item current is fitted with a straight line, and the inclination angle of the fitted straight line is recorded as a first inclination angle;

[0017] The sum of the first tilt angle and the first parameter adjustment constant is recorded as a first sum value;

[0018] The absolute value of the difference between the Hurst exponent of the trend item data sequence and the second parameter adjustment constant is recorded as the first difference;

[0019] The power with the natural constant as base and the first difference as exponent is recorded as the first value;

[0020] The ratio of the first sum value to the first value is recorded as the current correction stability coefficient of the current sequence.

[0021] Furthermore, the method for obtaining the first slope and current oscillation degree data sequence and then obtaining the current correction oscillation coefficient of the current sequence is:

[0022] Perform curve fitting on all seasonal item currents contained in the seasonal item data sequence to obtain a current change trend curve, wherein the abscissa of the current change trend curve is the data collection time of the current data corresponding to the trend item current, and the ordinate is the seasonal item current corresponding to the trend item current;

[0023] Obtain all extreme value points on the current change trend curve, arrange the data collection moments of the current data corresponding to all the extreme value points on the current change trend curve in chronological order, and obtain the fluctuation time sequence;

[0024] The difference sequence of the fluctuation time sequence is recorded as the current oscillation degree data sequence;

[0025] Fit the data contained in the flow oscillation degree data series to a straight line, and record the slope of the fitted straight line as the first slope;

[0026] The product of a power with a natural constant as a base and a first slope as an exponent and a mean value of all data included in the current oscillation degree data sequence is recorded as the current correction oscillation coefficient of the current sequence.

[0027] Further, the method for obtaining the charging current correction degree of the current sequence according to the first previous average value, the first subsequent average value and the current sequence is:

[0028] The sum of the variance of all current data contained in the current sequence and the third parameter adjustment constant is recorded as the second sum value;

[0029] The sum of the first mean value and the third parameter constant is recorded as the third sum value;

[0030] The product of the second sum and the third sum is recorded as the first product;

[0031] The ratio of the first average value to the first product is recorded as the charging current correction degree of the current sequence.

[0032] Further, the method of obtaining the temperature abnormal variation index and the voltage abnormal variation index according to the temperature sequence and the voltage sequence, obtaining the first correlation degree and the second correlation degree, and obtaining the external influencing factor of the current integral gain according to the temperature abnormal variation index, the voltage abnormal variation index, the first correlation degree and the second correlation degree is:

[0033] The product of the mean and variance of all temperature data contained in the temperature series is recorded as the temperature anomaly change index;

[0034] The product of the mean and variance of all voltage data contained in the voltage sequence is recorded as the voltage abnormal variation index;

[0035] According to the temperature sequence, the voltage sequence and the temperature sequence, the correlation degree between the temperature data and the current data and the correlation degree between the voltage data and the current data are obtained, and the correlation degree between the temperature data and the current data is recorded as a first correlation degree, and the correlation degree between the voltage data and the current data is recorded as a second correlation degree;

[0036] The product of the first correlation degree and the temperature anomaly variation index is recorded as the second product;

[0037] The product of the second correlation degree and the voltage abnormal variation index is recorded as a third product;

[0038] The sum of the second product and the third product is recorded as the external influencing factor of the current integral gain.

[0039] Furthermore, the method of performing constant current control according to the current integral gain coefficient and performing constant voltage control according to the voltage integral gain coefficient is:

[0040] When performing constant voltage control, a PI control algorithm is used for the voltage integral gain coefficient to obtain a deviation value between the voltage data and the preset voltage, and the preset voltage during the charging process is adjusted according to the deviation value;

[0041] When performing constant current regulation, a PI control algorithm is used for the current integral gain coefficient to obtain a deviation value between the current data and the preset current, and the preset current during the charging process is adjusted according to the deviation value.

[0042] In a second aspect, an embodiment of the present invention further provides a charging control system for a battery charger, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above methods when executing the computer program.

[0043] The beneficial effects of the present invention are:

[0044] The present invention analyzes the problem that the traditional PI control algorithm cannot dynamically adjust the integral gain coefficient in complex scenarios, resulting in poor control effect and poor stability. First, based on the data distribution of the charging current in the charging process of the charger, the current correction stability index and the current correction degree of the charging current are obtained, and the integral gain internal influence factor of the charging current is obtained. A smaller integral gain coefficient is assigned to the charging current at the time to be adjusted when the current correction stability index is smaller, thereby improving the stability of the charging current control system, and a larger integral gain coefficient is assigned to the charging current at the time to be adjusted when the current correction degree is smaller, thereby improving the accuracy of the charging current control; then, the integral gain external influence factor of the charging current is obtained according to the abnormal changes of data in other data sequences except the current and the correlation between different data and the charging current, and a smaller integral gain coefficient is assigned to the charging current at the time to be adjusted where abnormal current fluctuations may occur, thereby preventing the charging current from having large data fluctuations at the time to be adjusted; finally, the integral gain coefficient of the charging current is obtained based on the integral gain internal influence factor and the integral gain external influence factor of the charging current, and the battery charging circuit is regulated according to the integral gain coefficient, so that the regulation results of the charging current and the voltage are more accurate, thereby improving the stability and control accuracy of the charging control system of the battery charger. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0046] Figure 1 A schematic flow chart of a charging control method for a battery charger provided by an embodiment of the present invention;

[0047] Figure 2 It is a schematic diagram of the current change trend curve. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] See also Figure 1 , which shows a flow chart of a charging control method for a battery charger provided by an embodiment of the present invention, the method comprising the following steps:

[0050] Step S001, collecting the charging current, charging voltage and battery surface temperature when the battery charger is charging the battery, obtaining current data, temperature data and voltage data, and obtaining current sequence, voltage sequence and temperature sequence.

[0051] The current sensor, voltage sensor and temperature sensor are used to collect the charging current, charging voltage and battery surface temperature when the battery charger is charging the battery. The time interval, data collection time and data collection quantity of the current sensor, voltage sensor and temperature sensor are the same. The empirical value of the data collection quantity is 100, and the empirical value of the time interval of data collection is 0.05 seconds.

[0052] The collected charging currents are arranged in the order of data acquisition time to obtain a charging current sequence, the collected charging voltages are arranged in the order of data acquisition time to obtain a voltage sequence, and the collected battery surface temperatures are arranged in the order of data acquisition time to obtain a battery temperature sequence.

[0053] In order to avoid the impact of missing data on subsequent analysis during data collection and transmission, the mean filling method is used to fill the missing values ​​in the charging current sequence, voltage sequence and battery temperature sequence. The mean filling method is a well-known technology and will not be described in detail.

[0054] In order to avoid the influence of data dimension on subsequent analysis, the deviation standardization method is used to normalize the charging current series, voltage series and battery temperature series to obtain the current series, voltage series and temperature series. The deviation standardization method is a well-known technology and will not be described in detail.

[0055] The data in the current series is recorded as current data, the data in the temperature series is recorded as temperature data, and the data in the voltage series is recorded as voltage data.

[0056] At this point, the current sequence, voltage sequence and temperature sequence as well as current data, temperature data and voltage data are acquired.

[0057] Step S002, obtaining a current correction stability coefficient of the current sequence according to the current sequence, obtaining a first slope and a current oscillation degree data sequence, and then obtaining a current correction oscillation coefficient of the current sequence, and obtaining a current correction oscillation coefficient of the current sequence according to the current correction stability coefficient and the current correction oscillation coefficient.

[0058] In the process of battery charger controlling the battery charging, in order to ensure the normal charging of the battery, the charging process usually includes a constant current charging process and a constant voltage charging process. Taking the constant current charging process of the battery as an example, during the charging process of the battery, the charging current of the battery will be affected by factors such as the internal resistance of the battery, electromagnetic interference, and the charging voltage of the battery. This will cause the charging current of the battery to reach a relatively stable state after being adjusted by the battery charger. There is still a certain deviation between the charging current of the battery and the preset charging current, so that the value of the charging current of the battery cannot always reach the value of the preset charging current. The resulting deviation is called steady-state error.

[0059] The role of the integral gain coefficient in the PI control algorithm is to correct the deviation in the control system, that is, to eliminate the steady-state error in the control system. The larger the integral gain coefficient, the faster the steady-state response of the control system, and the faster the control system can eliminate the steady-state error, but the faster it is, the more likely it is to introduce oscillation; the smaller the integral gain coefficient, the slower the steady-state response of the control system, which is likely to cause the problem of insufficient correction of the steady-state error of the control system, affecting the control accuracy, but can prevent the control system from oscillating.

[0060] Therefore, the present invention adaptively adjusts the integral gain coefficient in the PI control algorithm according to the changes in the charging current and charging voltage of the battery charger and the factors affecting the charging current and charging voltage, so as to achieve a balance between the stability and control accuracy of the charging control system of the battery charger.

[0061] First, analysis is performed based on the current data contained in the current series.

[0062] In order to reduce the impact of noise in the current sequence on subsequent analysis, the current sequence is used Decomposition algorithm is used to process and obtain trend item data series and season item data series. The trend item data series can reflect the long-term evolution trend of the current data in the current series, and the season item data series can reflect the periodic changes of the current data in the current series. The decomposition algorithm is a well-known technique and will not be described in detail.

[0063] The data included in the trend item data sequence is recorded as trend item current, and the data included in the season item data sequence is recorded as season item current.

[0064] Get trend item data series Index. Among them, The acquisition of the index is a well-known technique and will not be described in detail.

[0065] Trend item data series The closer the index is to 0.5, the less long-term correlation the trend item current in the trend item data sequence has, that is, the current data in the current sequence has no long-term increasing or decreasing trend, that is, the overall change of the charging current data after adjustment by the battery charger tends to be more stable.

[0066] The least square method is used for the last first preset threshold trend item current in the trend item data sequence to fit the trend item current with a straight line, and the inclination angle of the fitted straight line is recorded as the first inclination angle. The first preset threshold empirical value is 10, and the least square method is a well-known technology and will not be described in detail.

[0067] The smaller the absolute value of the first inclination angle is, the more stable the change trend of the current data near the last moment of current acquisition is, that is, the overall change of the charging current data after adjustment by the battery charger is more stable.

[0068] According to the trend item data series of The exponent and the first tilt angle obtain the current correction stability coefficient of the current sequence.

[0069]

[0070] In the formula, represents the current correction stability coefficient of the current sequence; represents the first tilt angle; Represents the first parameter adjustment constant, which is used to prevent the value of the current correction stability coefficient from being 0, and the empirical value is 1; Represents a trend item data series of index; Represents the second parameter constant, the empirical value is 1; Represents a natural constant.

[0071] When the trend item data series The closer the index is to 0.5 and the larger the absolute value of the first inclination angle is, the larger the current correction stability coefficient of the current sequence is, that is, the overall change of the charging current data after adjustment by the battery charger tends to be more stable.

[0072] Use three times The spline interpolation method is used to perform curve fitting on all seasonal currents contained in the seasonal data sequence to obtain the current change trend curve. The horizontal axis of the current change trend curve is the data collection time of the current data corresponding to the trend item current, and the vertical axis is the seasonal current corresponding to the trend item current. The schematic diagram of the current change trend curve is shown in Figure 2 As shown. Three times The spline interpolation method is a well-known technology and will not be described in detail.

[0073] Obtain all extreme value points on the current change trend curve. The data collection time of the current data corresponding to the extreme value point is the time when the charging current fluctuates. Arrange the data collection time of the current data corresponding to all extreme value points on the current change trend curve in chronological order to obtain the fluctuation time sequence. Record the differential sequence of the fluctuation time sequence as the current oscillation degree data sequence.

[0074] The data contained in the flow oscillation degree data sequence are fitted with a straight line using the least square method, and the slope of the fitted straight line is recorded as the first slope. The mean of all the data contained in the flow oscillation degree data sequence is obtained.

[0075] The smaller the first slope is, the greater the decreasing trend of the current oscillation degree of the current data in the current sequence is. After the charging current is adjusted by the battery charger, the decreasing degree of the oscillation degree of the current data in the current sequence is greater, that is, the smaller the current oscillation degree of the charging current is.

[0076] The smaller the mean of all data contained in the current oscillation degree data sequence is, the smaller the overall current oscillation degree of the current data in the current sequence is, that is, after the current is adjusted by the battery charger, the current oscillation degree of the charging current is smaller.

[0077] The current correction oscillation coefficient of the current sequence is obtained according to the first slope and the mean value of all data contained in the current oscillation degree data sequence.

[0078]

[0079] In the formula, represents the current correction oscillation coefficient of the current sequence; represents the first slope; represents a natural constant; Indicates the mean of all data contained in the flow oscillation degree data series.

[0080] When the mean value of all data contained in the first slope and current oscillation degree data sequence is larger, the current correction oscillation coefficient of the current sequence is larger, that is, the current oscillation degree of the charging current is larger.

[0081] The current correction stability index of the current sequence is obtained according to the current correction stability coefficient and the current correction oscillation coefficient of the current sequence.

[0082]

[0083] In the formula, represents the current-corrected stability index of the current sequence; represents the current correction stability coefficient of the current sequence; Represents the current correction oscillation coefficient of the current sequence.

[0084] The larger the current correction stability coefficient of the current sequence and the smaller the current correction oscillation coefficient, the larger the current correction stability index of the current sequence, that is, after the charging current is adjusted by the battery charger, the smaller the current oscillation degree of the charging current data is, and the more stable the change of the charging current is.

[0085] The larger the current correction stability index of the current sequence, the stronger the stability of the charging current control system, and the less likely the charging current data will oscillate. Therefore, the integral gain coefficient should be larger to prevent the control system's steady-state error from being corrected in a timely manner and affecting the control accuracy. The smaller the current correction stability index of the current sequence, the worse the stability of the charging current control system, and the more likely the charging current data will oscillate. Therefore, the integral gain coefficient should be smaller to prevent the charging current control system from oscillating and enhance the stability of the charging current control system.

[0086] At this point, the current correction stability index of the current sequence is obtained.

[0087] Step S003, obtaining a first front mean value and a first rear mean value according to the current data contained in the current sequence, and obtaining a charging current correction degree of the current sequence according to the first front mean value, the first rear mean value and the current sequence.

[0088] While maintaining the stability of the charging current control system, the size of the steady-state error of the charging current control system should be reduced, that is, the value of the charging current obtained after adjustment by the battery charger should be close to the value of the preset charging current.

[0089] Get the variance and mean of all current data contained in the current series.

[0090] The difference between the current data included in the current sequence and the mean of all the current data included in the current sequence is recorded as the first difference of the current data, the mean of the first difference of the first second preset threshold current data included in the current sequence is recorded as the first mean, and the mean of the first difference of the second second preset threshold current data included in the current sequence is recorded as the last first mean. The second preset threshold is a rounded-down value of half the number of current data included in the current sequence.

[0091] The smaller the value of the rear first mean value is compared to the value of the front first mean value, the more obviously the error between the current data after the second preset threshold value in the current sequence and the preset charging current is smaller than the error between the current data before the second preset threshold value in the current sequence and the preset charging current, that is, after the battery charging current is adjusted by the battery charger, the error between the charging current and the preset charging current is reduced, the steady-state error of the charging current control system is reduced, and the charging current control system has a stronger ability to adjust the charging current.

[0092] The charging current correction degree of the current sequence is obtained according to the variance, the first previous mean value and the first subsequent mean value of all current data contained in the current sequence.

[0093]

[0094] In the formula, Indicates the charging current correction degree of the current sequence; Represents the third parameter constant, which is used to prevent the denominator from being 0, resulting in meaningless fractions. The empirical value is 1; Represents the variance of all current data contained in the current series; represents the first previous mean; represents the first post-mean.

[0095] When the variance of all current data contained in the current sequence and the first mean value are smaller and the first mean value is larger, the charging current correction degree of the current sequence is larger, that is, the charging current control system has a stronger ability to regulate the charging current, and the integral gain coefficient should be smaller to prevent the charging current control system from oscillating and enhance the stability of the charging current control system.

[0096] The ratio of the current correction stability index of the current sequence to the charging current correction degree is recorded as the internal influencing factor of the integral gain of the current sequence.

[0097] When the impact factor of the integral gain of the current sequence is smaller, the integral gain coefficient should be smaller.

[0098] At this point, the influencing factor of the integral gain of the current sequence is obtained.

[0099] Step S004, obtaining the temperature abnormal variation index and the voltage abnormal variation index according to the temperature sequence and the voltage sequence, obtaining the first correlation degree and the second correlation degree, obtaining the external influencing factor of the current integral gain according to the temperature abnormal variation index, the voltage abnormal variation index, the first correlation degree and the second correlation degree, obtaining the current integral gain coefficient according to the integral gain internal influencing factor of the current sequence and the current integral gain external influencing factor, obtaining the voltage integral gain coefficient according to the voltage sequence, performing constant current control according to the current integral gain coefficient, and performing constant voltage control according to the voltage integral gain coefficient.

[0100] When using a battery charger to charge the battery at a constant current, the battery charging voltage will continue to increase, and the increase in charging voltage will cause the battery charging current to decrease. The battery temperature will also gradually increase during the battery charging process. The increase in battery temperature will increase the internal resistance of the battery and reduce the battery charging current. When charging the battery at a constant voltage, the battery charging current and battery temperature will also affect the battery charging voltage.

[0101] The product of the mean and variance of all temperature data contained in the temperature series is recorded as the temperature anomaly variation index.

[0102] The larger the temperature anomaly variation index is, the more abnormal the temperature data change is.

[0103] The product of the mean and variance of all voltage data contained in the voltage sequence is recorded as the voltage abnormal variation index.

[0104] The larger the voltage abnormal variation index is, the more abnormal the voltage data variation is.

[0105] GRA grey correlation analysis is used on the temperature sequence, voltage sequence and temperature sequence to obtain the correlation between temperature data and current data and the correlation between voltage data and current data, and the correlation between temperature data and current data is recorded as the first correlation, and the correlation between voltage data and current data is recorded as the second correlation. Among them, GRA grey correlation analysis is a well-known technology and will not be repeated here.

[0106] The external influencing factor of the current integral gain is obtained according to the temperature abnormal variation index, the voltage abnormal variation index, the first correlation degree and the second correlation degree.

[0107]

[0108] In the formula, Represents the external influencing factor of current integral gain; represents the first degree of association; represents the second degree of association; Indicates the temperature abnormal change index; Indicates the voltage abnormal variation index.

[0109] When the temperature abnormal variation index, the voltage abnormal variation index, the first correlation degree and the second correlation degree are larger, the external influencing factor of the current integral gain is larger, that is, the possibility of abnormal variation in the charging current is greater, and the integral gain coefficient needs to be reduced to prevent large fluctuations in the current.

[0110] The current integral gain coefficient is obtained according to the integral gain internal influencing factor of the current sequence and the current integral gain external influencing factor.

[0111]

[0112] In the formula, Represents the current integral gain coefficient; Represents the influencing factor of the integral gain of the current sequence; Represents the external influencing factor of current integral gain; It is a normalization function, which is used to normalize the values ​​in brackets; Represents the first constant, the empirical value is 2; is the second constant, and its empirical value is 2; Represents the third tuning constant, which is used to prevent the denominator from being 0, resulting in a meaningless fraction. The empirical value is 1.

[0113] Similarly, the voltage integral gain coefficient is obtained according to the voltage sequence.

[0114] When performing constant voltage regulation, a PI control algorithm is used for the voltage integral gain coefficient to obtain a deviation value between the voltage data and the preset voltage, and the preset voltage during the charging process is adjusted according to the deviation value.

[0115] When performing constant current regulation, a PI control algorithm is used for the current integral gain coefficient to obtain a deviation value between the current data and the preset current, and the preset current during the charging process is adjusted according to the deviation value.

[0116] It should be noted that the constant voltage and constant current control are not carried out at the same time, but are carried out separately in stages. Generally, charging is carried out with a constant current first to increase the voltage. When the voltage reaches near the preset value, constant voltage control is performed and charging is carried out at a constant voltage.

[0117] At this point, the charging control of the battery charger is completed.

[0118] Based on the same inventive concept as the above method, an embodiment of the present invention also provides a charging control system for a battery charger, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above-mentioned charging control methods for a battery charger when executing the computer program.

[0119] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A charging control method for a battery charger, characterized in that: The method comprises the following steps: Collect the charging current, charging voltage and battery surface temperature when the battery charger is charging the battery, obtain current data, temperature data and voltage data, and obtain current sequence, voltage sequence and temperature sequence; Obtain a current correction stability coefficient of the current sequence according to the current sequence, obtain a first slope and a current oscillation degree data sequence, and then obtain a current correction oscillation coefficient of the current sequence, and obtain a current correction oscillation coefficient of the current sequence according to the current correction stability coefficient and the current correction oscillation coefficient; The ratio of the current correction stability coefficient of the current sequence to the current correction oscillation coefficient is recorded as the current correction stability index of the current sequence; Obtaining a first front mean value and a first rear mean value according to current data contained in the current sequence, and obtaining a charging current correction degree of the current sequence according to the first front mean value, the first rear mean value and the current sequence; The difference between the current data contained in the current sequence and the mean of all the current data contained in the current sequence is recorded as the first difference of the current data; the mean of the first difference of the first second preset threshold current data contained in the current sequence is recorded as the first mean; the mean of the first difference of the last second preset threshold current data contained in the current sequence is recorded as the last first mean; Obtain an abnormal temperature variation index and an abnormal voltage variation index according to the temperature sequence and the voltage sequence, obtain a first correlation degree and a second correlation degree, obtain an external influencing factor of the current integral gain according to the abnormal temperature variation index, the abnormal voltage variation index, the first correlation degree and the second correlation degree, obtain a current integral gain coefficient according to the integral gain internal influencing factor of the current sequence and the external influencing factor of the current integral gain, obtain a voltage integral gain coefficient according to the voltage sequence, perform constant current control according to the current integral gain coefficient, and perform constant voltage control according to the voltage integral gain coefficient; The sum of the external influencing factor of the current integral gain and the third parameter adjustment constant is recorded as the fourth sum value; the normalized value of the ratio of the internal influencing factor of the integral gain of the current sequence to the fourth sum value is recorded as the first normalized value; the product of the first normalized value and the first constant is summed with the second constant, and the result of the summation is recorded as the current integral gain coefficient; The method for obtaining the current correction stability coefficient of the current sequence according to the current sequence is: Obtain trend item data series and season item data series according to the current series; Record the data included in the trend item data sequence as trend item current, and record the data included in the season item data sequence as season item current; Using the least square method for the last first preset threshold trend item current in the trend item data sequence, the trend item current is fitted with a straight line, and the inclination angle of the fitted straight line is recorded as a first inclination angle; The sum of the first tilt angle and the first parameter adjustment constant is recorded as a first sum value; The absolute value of the difference between the Hurst exponent of the trend item data sequence and the second parameter adjustment constant is recorded as the first difference; The power with the natural constant as base and the first difference as exponent is recorded as the first value; The ratio of the first sum value to the first value is recorded as the current correction stability coefficient of the current sequence; The method for obtaining the first slope and current oscillation degree data sequence and then obtaining the current correction oscillation coefficient of the current sequence is: Perform curve fitting on all seasonal item currents contained in the seasonal item data sequence to obtain a current change trend curve, wherein the abscissa of the current change trend curve is the data collection time of the current data corresponding to the trend item current, and the ordinate is the seasonal item current corresponding to the trend item current; Obtain all extreme value points on the current change trend curve, arrange the data collection moments of the current data corresponding to all the extreme value points on the current change trend curve in chronological order, and obtain the fluctuation time sequence; The difference sequence of the fluctuation time sequence is recorded as the current oscillation degree data sequence; Fit the data contained in the flow oscillation degree data series to a straight line, and record the slope of the fitted straight line as the first slope; The product of a power with a natural constant as base and a first slope as exponent and the mean value of all data included in the current oscillation degree data sequence is recorded as the current correction oscillation coefficient of the current sequence; The method for obtaining the charging current correction degree of the current sequence according to the first previous average value, the first subsequent average value and the current sequence is: The sum of the variance of all current data contained in the current sequence and the third parameter adjustment constant is recorded as the second sum value; The sum of the first mean value and the third parameter constant is recorded as the third sum value; The product of the second sum and the third sum is recorded as the first product; Record the ratio of the first average value to the first product as the charging current correction degree of the current sequence; The method of obtaining the abnormal temperature variation index and the abnormal voltage variation index according to the temperature sequence and the voltage sequence, obtaining the first correlation degree and the second correlation degree, and obtaining the external influencing factor of the current integral gain according to the abnormal temperature variation index, the abnormal voltage variation index, the first correlation degree and the second correlation degree is: The product of the mean and variance of all temperature data contained in the temperature series is recorded as the temperature anomaly change index; The product of the mean and variance of all voltage data contained in the voltage sequence is recorded as the voltage abnormal variation index; According to the temperature sequence, the voltage sequence and the temperature sequence, the correlation degree between the temperature data and the current data and the correlation degree between the voltage data and the current data are obtained, and the correlation degree between the temperature data and the current data is recorded as a first correlation degree, and the correlation degree between the voltage data and the current data is recorded as a second correlation degree; The product of the first correlation degree and the temperature anomaly variation index is recorded as the second product; The product of the second correlation degree and the voltage abnormal variation index is recorded as a third product; The sum of the second product and the third product is recorded as the external influencing factor of the current integral gain.

2. A charging control method for a battery charger according to claim 1, characterized in that: The method of performing constant current control according to the current integral gain coefficient and performing constant voltage control according to the voltage integral gain coefficient is as follows: When performing constant voltage control, a PI control algorithm is used for the voltage integral gain coefficient to obtain a deviation value between the voltage data and the preset voltage, and the preset voltage during the charging process is adjusted according to the deviation value; When performing constant current regulation, a PI control algorithm is used for the current integral gain coefficient to obtain a deviation value between the current data and the preset current, and the preset current during the charging process is adjusted according to the deviation value.

3. A charging control system for a battery charger, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 2 are implemented.

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