A method for quickly locating and detecting abnormalities in energy storage batteries

Abstract

The present invention provides a method for quickly locating and detecting abnormalities in energy storage batteries, belonging to the technical field of battery abnormality detection. The present invention uses a single power supply analog switch to quickly locate and detect the access position of the system, reducing the number of measuring devices, simplifying the complexity of the measuring devices, reducing the space occupation, improving the space utilization rate, and reducing the measurement cost; using the internal resistance data of multiple switching states to locate the abnormal interval of the battery, reducing the amount of measurement data, achieving quick location of abnormalities in energy storage batteries, reducing the probability of accidents, and reducing the cost of the system. The present invention can not only be applied to the abnormal location technology of internal resistance detection of energy storage batteries, but also be applied to the corresponding electrical detection fields, and is widely extended with broad application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery anomaly detection, and particularly relates to a method for quickly locating and detecting anomalies in energy storage batteries. Background Art

[0002] As a power source, lithium-ion batteries must be used in series to meet the voltage requirements. After multiple batteries are used in series for a period of time, the internal resistance and voltage of the batteries fluctuate, and the state differences of individual batteries will gradually become apparent. The continuous charging and discharging process exacerbates the inconsistency between individual batteries. Due to the increasing inconsistency of the batteries, in a battery system connected in series, the individual battery with poor electrical performance affects the overall performance of the battery pack. If not discovered in time, the abnormal battery will pose a threat to the safety of the entire battery pack. In a large-scale energy storage system, the cost of batteries accounts for about half of the total cost, resulting in huge cost losses. However, often lost is not only the expensive batteries, but also system paralysis and data loss caused by the uncertainty of the battery state, and the consequences are unthinkable. Therefore, to ensure the good performance of the energy storage system, extend the service life of the batteries, and timely detect the aging and possible anomalies of the batteries, it is particularly important to locate and replace the abnormal batteries with abnormal internal resistance values.

[0003] When the existing detection methods locate abnormal batteries, most of them need to obtain the internal resistance parameters of each individual battery and then compare these data. This method not only requires complex detection equipment and high costs, but also is time-consuming and laborious, with low efficiency, seriously affecting the detection efficiency of energy storage batteries.

[0004] For example, CN215731869U discloses a power battery anomaly location system for new energy vehicles, which uses optical fibers to monitor the temperature of power batteries and realizes the location of individual batteries with abnormal temperature through the cooperation of a laser generating device, a conversion device, and a microprocessor. However, the detection equipment of this method is complex, occupies a large space, reduces the utilization rate of the space of the battery pack, and reduces the volume energy density of the battery. CN103094633A discloses a detection and maintenance system for power batteries of electric vehicles, which locates and screens out abnormal individual batteries in the battery pack to be tested by reasonably calculating parameters such as the capacity, internal resistance, polarization, and consistency of the battery pack and individual batteries. However, this method needs to obtain parameters such as the capacity, internal resistance, polarization, and consistency of each individual battery for comparison. This method requires a large amount of data acquisition, complex detection equipment, high costs, and long detection times, which is not conducive to the rapid screening of abnormal individual batteries.

[0005] Therefore, for the purposes of high efficiency, accuracy, and economy, it has become a necessary research topic to revolutionarily innovate and design the problems existing in the above-mentioned several energy storage battery anomaly location monitoring methods, which has important theoretical significance and practical application value. Summary of the Invention

[0006] In order to solve the problems of complex detection equipment, high cost, large amount of data, slow detection speed, and low space utilization rate in the process of the energy storage battery anomaly location method, the present invention innovatively designs the design idea of the traditional energy storage battery anomaly location detection method, and proposes a monitoring method for quickly locating the anomalies of energy storage batteries. This method has the advantages of simplicity, safety, easy operation, low cost, and rapidity.

[0007] To achieve the above object, the technical solution of the present invention is as follows:

[0008] A rapid location detection method for energy storage battery anomalies, which is implemented by using a rapid location detection system. The rapid location detection system includes an MCU (Microcontroller Unit), an excitation source module, a data acquisition module, a GPS (Global Positioning System) synchronization module, and a host computer.

[0009] The excitation source module is connected in the middle of two battery strings through a single-power analog switch, and the program parameters of the MCU are modified through a serial port to change the frequency and current amplitude of the excitation source.

[0010] The data acquisition module includes a current sampling circuit and a voltage sampling circuit. Among them, the current sampling circuit is connected to the A / D port of the MCU, and the current signals of the upper and lower half-bridges (taking the rapid location detection system as the boundary, the circuit above the rapid location detection system is called the upper half-bridge, and the circuit below the rapid location detection system is called the lower half-bridge) are sampled in real time by using the current continuous sampling algorithm and the current sampling waveform is recorded; the voltage sampling circuit is connected to the A / D port of the MCU, and the voltage response signal of the battery is sampled in real time by using the voltage continuous sampling algorithm and the voltage sampling waveform is recorded and stored in the internal resistance calculation module of the MCU.

[0011] The GPS synchronization module receives the timing information of the GPS, and at the same time outputs the IRIG-B code and inputs it into the MCU, and the "timestamp" information is decoded and extracted and stored in the internal resistance calculation module in the MCU.

[0012] The internal resistance calculation module in the MCU processes and calculates the stored data to obtain the battery internal resistance, which is stored in the host computer connected to the MCU, providing a data source for the subsequent rapid location of the battery anomaly range by the host computer.

[0013] The rapid location detection method for energy storage battery anomalies includes the following steps:

[0014] Step 1: Connect the rapid location detection system to multiple equipotential positions of two battery strings through a single-power analog switch.

[0015] Step 2: Set the excitation amplitude and frequency of the excitation source to generate a constant alternating current excitation signal.

[0016] Step 3: The GPS synchronization module receives the time synchronization information of GPS, outputs the IRIG-B code and inputs it into the MCU, and decodes and extracts the "timestamp" information to be stored in the internal resistance calculation module of the MCU.

[0017] Step 4: The counter in the MCU decrements once per second according to the PPS pulse output by the GPS synchronization module. When the counter reaches zero, the MCU outputs an A / D synchronization trigger signal to trigger the two sampling circuits in the data acquisition module to work synchronously.

[0018] Step 5: Use the current continuous sampling algorithm to sample the current excitation signal of the excitation source in real time through the current sampling circuit and record the current sampling waveform, which is stored in the internal resistance calculation module of the MCU.

[0019] Step 6: Use the voltage continuous sampling algorithm to sample the voltage response signal of the battery in real time through the voltage sampling circuit and record the voltage sampling waveform, which is stored in the internal resistance calculation module of the MCU.

[0020] Step 7: The internal resistance calculation module in the MCU calculates and processes the current excitation signal of the excitation source, the voltage response signal of the battery, and the "timestamp" information to determine the internal resistance of the battery and Specifically, it includes the following steps:

[0021] Step 7.1: Align the voltage sampling waveform and the current sampling waveform through the "timestamp" information.

[0022] Step 7.2: Traverse the zero-crossing points of the voltage sampling and the zero-crossing points of the current sampling, and calculate the sampling time difference Δt between the two.

[0023] Step 7.3: Determine the phase difference θ of the voltage and current signals according to the impedance formula θ = 360°Δt / T, where T = 1 / f and f is the frequency of the excitation source.

[0024] Step 7.4: Traverse all sampling points, obtain the sampling time difference Δt within multiple periods, and calculate the phase average difference of the voltage and current signals

[0025] Step 7.5: Traverse the sampling point data within one period for calculation, and calculate the effective voltage U and the effective current I.

[0026] Step 7.6: Determine the internal resistance Re(Z) and Im(Z) of the battery according to the impedance formula Z = U / I and

[0027] Step 7.7: Traverse all sampling points to obtain the effective voltage values and effective current values within multiple cycles, and repeat Step 7.6 to calculate the internal resistance Re(Z) and Im(Z); then take the average values of the internal resistances respectively and to reduce errors.

[0028] Step 8: The single-power analog switch switches to locate the access position of the detection system, and repeat Steps 3 - 8.

[0029] Step 9: The MCU sends the battery internal resistance information to the host computer.

[0030] Step 10: The host computer processes the data through Formulas (1) - (6), and compares the processed internal resistances R and X of each layer of batteries with the set threshold values respectively to quickly locate the abnormal battery interval.

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[0037] Among them, i is the state when the single-power analog switch switches to the i-th state, 0 is the upper half-bridge measurement state, 1 is the lower half-bridge measurement state, and N is the number of series-connected single cells in each battery string.

[0038] Furthermore, the "timestamp" information in Step 3 refers to processing the IRIG-B code and decoding it to extract the time information, which is marked on each segment of the current sampling waveform and voltage sampling waveform, so that each segment of the current sampling waveform and voltage sampling waveform has a time record. The subsequent sampling times of the two are aligned through the time record, and the "timestamp" information is stored for subsequent phase difference acquisition.

[0039] Advantages of the present invention: The method for quickly locating and detecting abnormal energy storage batteries of the present invention uses a single - power analog switch to quickly locate the access position of the detection system, reducing the number of measuring devices, simplifying the complexity of the measuring devices, reducing the space occupation, improving the space utilization rate, and reducing the measurement cost; using the internal resistance data of multiple switching states to locate the abnormal interval of the battery, reducing the amount of measurement data, achieving quick location of abnormal energy storage batteries, reducing the probability of faults, and reducing the cost of the system. The present invention can not only be applied to the technology of abnormal location detection of the internal resistance of energy storage batteries, but also to the corresponding electrical detection fields, and has a broad application prospect with extensive extension. Brief Description of the Drawings

[0040] Figure 1 is the overall schematic diagram of the present invention.

[0041] Figure 2 is the connection circuit of the quick - location detection system of the present invention.

[0042] Figure 3 is the schematic diagram of the single - power analog switch switching of the present invention; where (a) is the measurement schematic diagram when the single - power analog switch is switched to state ①, (b) is the measurement schematic diagram when the single - power analog switch is switched to state ②, and (c) is the measurement schematic diagram when the single - power analog switch is switched to state ③.

[0043] Figure 4 is the flow chart of quickly locating the abnormal interval of the battery of the present invention.

[0044] Figure 5 is the schematic diagram of the expansion of the increase in the number of parallel battery strings of the present invention.

[0045] Figure 6 is the schematic diagram of quickly locating abnormal energy storage batteries of the present invention; where (a) is the measurement schematic diagram when the quick - location detection system one runs alone, (b) is the measurement schematic diagram when the quick - location detection system two runs alone, and (c) is the measurement schematic diagram when the quick - location detection system three runs alone. Detailed Embodiments

[0046] In order to make the purpose, technical solutions and advantages of the present invention clearer, the following further elaborates on the present invention in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0047] As Figure 1As shown in the figure, the present invention provides a method for quickly locating and detecting abnormal energy storage batteries. In this method, a quick location detection system that can generate a constant AC excitation current signal is connected between two battery strings through a single - power analog switch to generate a current excitation for the battery strings. The current continuous sampling algorithm is used to continuously sample the current excitation signal of the excitation source in real - time through the current sampling circuit and record the current sampling waveform, which is stored in the internal resistance calculation module of the MCU. At the same time, the voltage continuous sampling algorithm is used to continuously sample the voltage response signal of the battery in real - time through the voltage sampling circuit and record the voltage sampling waveform, which is also stored in the internal resistance calculation module of the MCU. The GPS synchronization module receives the timing information of the GPS, and at the same time outputs the IRIG - B code and inputs it into the MCU. The time information is decoded and extracted, and "timestamps" are added to the current sampling waveform and the voltage sampling waveform, which are stored in the internal resistance calculation module of the MCU. The internal resistance calculation module in the MCU aligns the voltage sampling waveform and the current sampling waveform through the "timestamp" information, calculates the sampling time difference between the zero - crossing points of the voltage sampling and the current sampling to determine the phase difference θ of the voltage - current signal, and determines the internal resistance R and X of the battery according to the impedance formula from the current excitation signal of the excitation source, the voltage response signal of the battery, and the phase difference. By switching the state of the single - power analog switch to change the access point of the quick location detection system, the above process is repeated to obtain the internal resistance parameters of the batteries in all intervals (layers). The obtained battery internal resistance information is calculated by the host computer to quickly locate the abnormal battery interval.

[0048] The specific implementation steps of the above - mentioned method for quickly locating and detecting abnormal energy storage batteries are as follows:

[0049] Step 1: Connect the quick location detection system between multiple equipotential positions of two battery strings through a single - power analog switch.

[0050] Step 2: Set the excitation amplitude and frequency of the excitation source to generate a constant AC excitation current signal.

[0051] Step 3: The GPS synchronization module receives the timing information of the GPS, outputs the IRIG - B code and inputs it into the MCU. The time information is decoded and extracted and stored in the internal resistance calculation module of the MCU.

[0052] Step 4: The counter decreases its value once per second according to the PPS pulse output by the GPS synchronization module. When the counter reaches zero, the MCU outputs an A / D synchronization trigger signal to trigger the synchronous sampling of the two sampling circuits in the data acquisition module.

[0053] Step 5: Use the current continuous sampling algorithm to continuously sample the current excitation signal of the excitation source in real - time through the current sampling circuit and record the current sampling waveform, which is stored in the internal resistance calculation module of the MCU.

[0054] Step 6: Use the voltage continuous sampling algorithm to sample the voltage response signal of the battery in real time through the voltage sampling circuit, record the voltage sampling waveform, and store it in the internal resistance calculation module of the MCU.

[0055] Step 7: The internal resistance calculation module in the MCU calculates and processes the current excitation signal of the excitation source, the voltage response signal of the battery, and the "timestamp" information to determine the internal resistance of the battery and Specifically, it includes the following steps:

[0056] Step 7.1: Align the voltage sampling waveform and the current sampling waveform through the "timestamp" information.

[0057] Step 7.2: Traverse the zero-crossing points of the voltage sampling and the zero-crossing points of the current sampling, and calculate the sampling time difference Δt between the two.

[0058] Step 7.3: Determine the phase difference θ of the voltage and current signals according to the impedance formula θ = 360°Δt / T, where T = 1 / f and f is the frequency of the excitation source.

[0059] Step 7.4: Traverse all sampling points, obtain the sampling time difference Δt within multiple cycles, and calculate the phase average difference of the voltage and current signals

[0060] Step 7.5: Traverse the sampling point data within one cycle for calculation, and calculate the effective voltage U and the effective current I.

[0061] Step 7.6: Determine the internal resistance Re(Z) and Im(Z) of the battery according to the impedance formula Z = U / I and to determine the internal resistance Re(Z) and Im(Z) of the battery.

[0062] Step 7.7: Traverse all sampling points, obtain the effective voltage and the effective current within multiple cycles, repeat Step 7.6 to calculate the internal resistance Re(Z) and Im(Z); then take the average value of the internal resistance respectively and to reduce the error.

[0063] Step 8: The single-power analog switch switches the connection positions of the excitation source and the response signal measurement device, and repeats Steps 3-8.

[0064] Step 9: The MCU sends the battery internal resistance information to the host computer.

[0065] Step 10: The host computer processes the data and compares the internal resistance R and X of each layer of the battery with the set threshold values respectively to quickly locate the abnormal interval of the battery. Specifically, it includes the following steps:

[0066] Step 10.1: Such as Figure 3Taking a battery string with four single cells (four layers of cells) as shown as an example, the internal resistance of the upper half-bridge cells is measured in the single-power analog switch state ① and and the internal resistance of the lower half-bridge cells and The internal resistance of the upper half-bridge cells in the switch state ② and and the internal resistance of the lower half-bridge cells and The internal resistance of the upper half-bridge cells in the switch state ③ and and the internal resistance of the lower half-bridge cells and

[0067] Step 10.2: Calculate the internal resistance R and X of the four layers of I, II, III, and IV respectively through formulas (1)-(8);

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[0076] Step 10.3: Compare the internal resistance R and X of each layer of cells with the set threshold values respectively to quickly judge the battery fault interval.

[0077] Furthermore, by analogy, as the number of battery layers increases or decreases, this solution is still applicable. As the number of battery layers increases, the positioning effect of this method becomes more prominent.

[0078] Furthermore, as shown in Figure 5 When the number of battery strings increases, this solution is still applicable. As the number of battery strings increases, the number of corresponding fast positioning detection systems needs to be increased, and the positioning effect of this method becomes more prominent. By switching the working state of the fast positioning detection system and the access positions of the excitation source and the response signal measurement device through the single-power analog switch, this method is realized.

[0079] Specifically, as shown in Figure 6As shown, when the state of the leftmost upper - left battery is abnormal, the rapid positioning detection method for abnormal energy - storage batteries can detect Figure 6 (a) It is detected that there is an abnormality in layer I, Figure 6 (b) It is detected that there is an abnormality in layer I, Figure 6 (c) No abnormality is detected. Based on the above information, the host computer can accurately locate that the leftmost upper - left battery has an abnormal state, achieving the effect of accurate positioning. Thus, it is proved that as the number of replacement batteries and the number of battery strings increase, the rapidity and accuracy of this method become more significant.

[0080] The set amplitude, frequency value, and set threshold are respectively fixed reference values. These reference values are specifically set according to those skilled in the art and the actual specific implementation situations, that is, they need to be adjusted according to the specific type of the battery to be measured. For example, different reference values are set for different ranges of the battery to be measured, and this is achievable and reasonable within the protection scope of the present invention.

[0081] In summary, for the rapid positioning detection method for abnormal energy - storage batteries described in the present invention, by using a single - power - supply analog switch to switch the excitation source and the access position of the response - signal measuring device, the number of measuring devices is reduced, the complexity of the measuring devices is lowered, the space occupation is reduced, the space utilization rate is improved, and the measurement cost is reduced; by using the internal - resistance data of several switching states to judge the abnormal interval of the battery, the amount of measurement data is reduced, the rapid positioning of the abnormal interval of the energy - storage battery is realized, the probability of faults is reduced, and the cost of the system is reduced; the present invention can not only be applied to the abnormal - positioning technology for the internal resistance detection of energy - storage batteries, but also be applied to the corresponding electrical detection fields, and is widely extended with broad application prospects.

Claims

1. A rapid positioning detection method for energy storage battery anomalies, characterized in that, This method is implemented based on a fast positioning detection system, and the fast positioning detection system includes an MCU, an excitation source module, a data acquisition module, a GPS synchronization module, and a host computer; The excitation source module is connected between two battery strings through a single - power analog switch, and the program parameters of the MCU are modified through a serial port to change the frequency and current amplitude of the excitation source; The data acquisition module includes a current sampling circuit and a voltage sampling circuit; among them, the current sampling circuit is connected to the A / D port of the MCU, and uses the current continuous sampling algorithm to sample the current signals of the upper and lower half - bridges in real - time and record the current sampling waveform; among them, taking the fast positioning detection system as the boundary, the circuit above the fast positioning detection system is called the upper half - bridge, and the circuit below the fast positioning detection system is called the lower half - bridge; the voltage sampling circuit is connected to the A / D port of the MCU, and uses the voltage continuous sampling algorithm to sample the voltage response signal of the battery in real - time and record the voltage sampling waveform, which is stored in the internal resistance calculation module of the MCU; The GPS synchronization module receives the timing information of GPS, and at the same time outputs the IRIG - B code and inputs it into the MCU, and decodes and extracts the "timestamp" information and stores it in the internal resistance calculation module of the MCU; The internal resistance calculation module in the MCU processes and calculates the stored data to obtain the battery internal resistance, which is stored in the host computer connected to the MCU, providing a data source for the subsequent fast positioning of the battery abnormal interval by the host computer; The fast positioning detection method for energy storage battery anomalies includes the following steps: Step 1: Connect the above - mentioned fast positioning detection system to multiple equipotential positions of two battery strings through a single - power analog switch; Step 2: Set the excitation amplitude and frequency of the excitation source to generate a constant AC excitation current signal; Step 3: The GPS synchronization module receives the timing information of GPS, outputs the IRIG - B code and inputs it into the MCU, and decodes and extracts the "timestamp" information and stores it in the internal resistance calculation module of the MCU; Step 4: The counter in the MCU decreases by one per second according to the PPS pulse output by the GPS synchronization module. When the counter reaches zero, the MCU outputs an A / D synchronization trigger signal to trigger the synchronous operation of the two sampling circuits in the data acquisition module; Step 5: Use the current continuous sampling algorithm to sample the current excitation signal of the excitation source in real - time through the current sampling circuit and record the current sampling waveform, which is stored in the internal resistance calculation module of the MCU; Step 6: Use the voltage continuous sampling algorithm to sample the voltage response signal of the battery in real - time through the voltage sampling circuit and record the voltage sampling waveform, which is stored in the internal resistance calculation module of the MCU; Step 7: The internal resistance calculation module in the MCU processes the current excitation signal of the excitation source, the voltage response signal of the battery, and the "timestamp" information through calculation to determine the internal resistance of the battery and Step 8: The single - power analog switch switches the access position of the fast positioning detection system, and repeat steps 3 - 8; Step 9: The MCU sends the battery internal resistance information to the host computer; Step 10: The host computer processes the data, compares the internal resistance R and X of each layer of battery obtained by processing with the set threshold values respectively, and quickly locates the battery abnormal interval.

2. The rapid positioning detection method for an abnormal energy storage battery according to claim 1, characterized in that, The specific content of step 7 includes the following steps: Step 7.1: Align the voltage sampling waveform and the current sampling waveform through the "timestamp" information; Step 7.2: Traverse the zero-crossing points of voltage sampling and current sampling, and calculate the sampling time difference Δt between the two; Step 7.3: Determine the phase difference θ between the voltage and current signals according to the impedance formula θ = 360°·Δt / T, where T = 1 / f and f is the frequency of the excitation source; Step 7.4: Traverse all the sampling points, obtain the sampling time difference Δt within multiple cycles, and calculate the phase average difference of the voltage and current signals Step 7.5: Traverse the sampled point data within one cycle for calculation, and calculate the effective voltage U and effective current I; Step 7.6: Determine the internal resistance Re(Z) and Im(Z) of the battery according to the impedance formula Z = U / I and ; Step 7.7: Traverse all sampling points to obtain the effective voltage and effective current within multiple cycles, and repeat Step 7.6 to calculate the internal resistance Re(Z) and Im(Z); then take the average values of the internal resistances respectively and to reduce errors.

3. A method for quickly locating and detecting an abnormality of a energy storage battery according to claim 1 or 2, characterized in that, In the said Step 10, the host computer processes the data according to Formulas (1)-(6) to obtain the internal resistance R and X of each layer of battery: where i is the state when the single-power analog switch switches to the i-th state, 0 is the upper half-bridge measurement state, 1 is the lower half-bridge measurement state, and N is the number of series-connected single cells in each battery string.

4. A method for quickly locating and detecting abnormalities of an energy storage battery according to claim 1 or 2, characterized in that, In the said Step 3, the "timestamp" information refers to performing IRIG-B encoding and decoding processing, extracting the time information therein, and marking it on each current sampling waveform and voltage sampling waveform, so that each current sampling waveform and voltage sampling waveform have time records. Align the subsequent sampling times of the two through the time records, and store the "timestamp" information for subsequent phase difference acquisition.

5. A method for quickly locating and detecting abnormalities of an energy storage battery according to claim 3, characterized in that, In the said Step 3, the "timestamp" information refers to performing IRIG-B encoding and decoding processing, extracting the time information therein, and marking it on each current sampling waveform and voltage sampling waveform, so that each current sampling waveform and voltage sampling waveform have time records. Align the subsequent sampling times of the two through the time records, and store the "timestamp" information for subsequent phase difference acquisition.

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