Storage battery online monitoring system and method

Abstract

The invention provides an on-line monitoring system and method for a storage battery, and relates to the technical field of battery detection, and the system comprises a normal state monitoring module which is used for continuously collecting a first operation parameter related to the storage battery in a normal operation state of the storage battery; the step-down monitoring module is used for continuously collecting a second operation parameter related to the storage battery in the independent on-load operation state of the storage battery; the switching control module is used for periodically switching the operation state of the storage battery and controlling the monitoring actions of the normal state monitoring module and the voltage reduction monitoring module after switching; the summarizing and analyzing module is used for summarizing the first operation parameter and the second operation parameter in one period and analyzing the effectiveness and the internal resistance change rate of the storage battery; the early warning module is used for generating a corresponding early warning signal according to the analysis result; according to the invention, comprehensive parameter monitoring, effectiveness evaluation, intelligent early warning and fault diagnosis effects can be realized, the accuracy and reliability of storage battery monitoring are improved, and stable operation of related systems is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of battery monitoring, and in particular to a battery online monitoring system and method. Background Art

[0002] In the early stages of development of power systems and communications, battery monitoring was relatively simple and extensive. The battery voltage was measured manually using basic measuring tools such as multimeters to roughly determine the battery status. This method can only detect the most basic electrical parameters of the battery, and manual operation is inefficient, prone to measurement errors and omissions, and unable to detect potential battery problems in a timely manner. With the development of electronic technology and automation technology, some simple online monitoring devices have emerged. These devices can monitor battery voltage, current and other parameters in real time, and transmit data to the monitoring center via wired transmission. At the same time, attention has also been paid to the impact of battery temperature on its performance, and some monitoring systems have added temperature sensors.

[0003] In recent years, with the rise of big data, artificial intelligence and the Internet of Things, online battery monitoring technology has developed rapidly. Modern monitoring systems can not only collect multiple parameters in real time, such as voltage, current, temperature, internal resistance, etc., but also use advanced algorithms to conduct in-depth analysis of these data to achieve accurate evaluation and prediction of battery status.

[0004] However, many existing monitoring systems mainly focus on conventional parameters such as voltage, current and temperature, but do not pay enough attention to the monitoring of changes in battery internal resistance or the monitoring accuracy is not high; however, the internal resistance of a battery is an important indicator of its internal health status. The increase in internal resistance often indicates problems such as battery plate aging, sulfation, and poor connection, but the existing technology is difficult to accurately and timely detect the potential risks brought by changes in internal resistance; at the same time, the existing technology's evaluation method for battery effectiveness is relatively simple, usually based on parameters at a single moment, which leads to inaccurate evaluation of the effective power and continuous power supply capacity that the battery can actually provide, and cannot provide an accurate basis for the reliable operation of the system;

[0005] In addition, battery monitoring systems produced by different manufacturers often use their own independent communication protocols and interface standards, which makes it difficult to interconnect and centrally manage multiple battery monitoring devices of different brands or models in a complex power or communication system. At the same time, when the system needs to be upgraded or expanded, the existing monitoring system may not be able to be easily compatible and connected with the new equipment or technology, increasing the cost and difficulty of system upgrades and maintenance.

[0006] Therefore, how to provide a battery online monitoring system and method has become a problem to be solved by those skilled in the art. Summary of the invention

[0007] The present invention provides a battery online monitoring system and method, aiming to solve the problems existing in the above-mentioned prior art, and improve the accuracy and reliability of battery monitoring and ensure the stable operation of related systems through innovative designs in comprehensive monitoring parameters, accurate effectiveness evaluation, intelligent early warning and fault diagnosis, and improving system compatibility and scalability.

[0008] In one aspect, the present invention provides a battery online monitoring system, comprising:

[0009] A normal monitoring module, which is connected to the battery pack and is used to continuously collect first operating parameters related to the battery when the battery is in normal operating state;

[0010] A voltage reduction monitoring module connected to the battery pack and used for continuously collecting a second operating parameter related to the battery when the battery is operating alone with a load;

[0011] A switching control module, which is electrically connected to the normal monitoring module, the voltage reduction monitoring module, the battery pack and the DC bus, and is used to periodically switch the operating state of the battery and control the monitoring actions of the normal monitoring module and the voltage reduction monitoring module after switching;

[0012] A summary analysis module, connected to the normal monitoring module and the voltage reduction monitoring module, for summarizing the first operating parameter and the second operating parameter in a cycle, and analyzing the battery effectiveness and internal resistance change rate;

[0013] The early warning module is connected to the summary analysis module and is used to generate a corresponding early warning signal according to the analysis results.

[0014] According to a battery online monitoring system provided by the present invention, the normal monitoring module comprises:

[0015] The voltage acquisition unit is connected to the battery pack and the DC bus and is used to collect the bus voltage U when the battery is operating normally. n1 and the battery terminal voltage U n2 ;

[0016] The current collection unit is connected to the output line of the battery pack and is used to collect the output current I during normal operation. n ;

[0017] The temperature collection unit is installed on the surface of the battery pack to collect the temperature T of the battery pack. n ;

[0018] The data integration unit is connected to the voltage acquisition unit, the current acquisition unit and the temperature acquisition unit, and is used to integrate and package the collected voltage, current and temperature data to form a first operating parameter set.

[0019] According to a battery online monitoring system provided by the present invention, the voltage reduction monitoring module comprises:

[0020] The step-down voltage acquisition unit is connected between the battery pack and the DC bus and is used to collect the stepped-down bus voltage U when the battery is operating alone with load. d1 And the battery output voltage U d2 ;

[0021] The single load current acquisition unit is connected to the battery output line to collect the output current I of the battery when it is loaded alone. d ;

[0022] The step-down parameter integration unit is connected to the step-down voltage acquisition unit and the separate load current acquisition unit, and is used to integrate the collected step-down voltage and current data to form a second operation parameter set.

[0023] According to a battery online monitoring system provided by the present invention, the switching control module comprises:

[0024] A state switching unit, connected to the battery pack, the DC bus, the normal monitoring module and the voltage reduction monitoring module, and used to switch the operating state of the battery between normal operation and single load operation according to a preset cycle or system instruction;

[0025] A monitoring control unit, connected to the normal monitoring module, the voltage reduction monitoring module and the state switching unit, for generating a feedback signal after the state switching unit completes the operation state switching, and sending a control instruction to the normal monitoring module and the voltage reduction monitoring module according to the feedback signal to start or stop the corresponding monitoring action;

[0026] The protection unit is connected to the battery pack, the DC bus, the state switching unit and the monitoring control unit, and is used to protect the battery pack, the DC bus and related circuit equipment from damage caused by abnormal voltage and current during the switching control process.

[0027] According to a battery online monitoring system provided by the present invention, the summary analysis module includes:

[0028] a parameter receiving unit, connected to the data integration unit and the voltage reduction parameter integration unit, and configured to receive a first operating parameter set and a second operating parameter set;

[0029] An effectiveness analysis unit, connected to the parameter receiving unit, for calculating the effectiveness index E of the current battery according to the received parameters and a preset effectiveness analysis model;

[0030] The internal resistance analysis unit is connected to the parameter receiving unit and is used to calculate the internal resistance change rate index r of the current battery according to the received parameters and a preset internal resistance change rate analysis model.

[0031] According to a battery online monitoring system provided by the present invention, the effectiveness analysis model is:

[0032]

[0033] Among them, E is the effectiveness index of the current battery; U n1 is the bus voltage during normal monitoring, U d1 is the bus voltage during voltage reduction monitoring; C is the rated capacity of the battery, which is determined by the battery specifications; k T is the temperature correction coefficient, and k T =1+i T *(T-25), T is the battery pack temperature T during this cycle n The average temperature, i T is the temperature proportionality coefficient, determined based on experiments, indicating the proportion of the effect of the average temperature deviation from the reference temperature on the battery performance. The reference temperature is set to 25 degrees Celsius. The temperature correction coefficient k T Used to reflect the impact of temperature on battery performance; a A is the battery aging coefficient, and a A =i T *y, y is the year of use of the battery, i T The annual aging coefficient is determined based on long-term tracking or aging mechanism estimation, indicating the proportion of the impact of the use year on the battery performance. A Used to reflect the impact of the use year on battery performance; s is the battery self-discharge rate, which is determined by the type of battery; t is the time of a monitoring cycle; η is the battery charge and discharge efficiency, which is determined according to the battery model; I n It is the output current during normal monitoring;

[0034] The effectiveness index E comprehensively evaluates the effectiveness of the battery based on the voltage change, capacity, temperature, aging degree, self-discharge rate, and charge and discharge efficiency of the battery under different operating conditions.

[0035] According to a battery online monitoring system provided by the present invention, the internal resistance change rate analysis model is:

[0036]

[0037] Among them, r is the internal resistance change rate index; is the battery internal resistance calculated during voltage reduction monitoring, U d2is the output voltage of the battery during step-down monitoring, I d is the output current during step-down monitoring; is the internal resistance of the battery calculated during normal monitoring, U n2 is the terminal voltage of the battery itself during normal monitoring, I n is the output current during normal monitoring; (R c *l) is the connection resistance, where l is the length of the battery connection line, R c is the resistance length coefficient, determined based on experimental measurements, and used to reflect the contribution of the connection line per unit length to the resistance; {R ct *(1 - k p )} is the contact resistance, k p is the contact pressure coefficient, estimated according to the contact pressure at the connection part, R ct is the contact resistance pressure coefficient, indicating the proportion of the influence of the contact pressure coefficient k p on the contact resistance, determined based on experimental simulation and fitting;

[0038] The internal resistance change rate index r is obtained by comparing the internal resistance of the battery in different operating states and considering the influence of the connection resistance and the contact resistance, so as to evaluate the health status of the internal structure and connection of the battery.

[0039] According to an on-line monitoring system for a battery provided by the present invention, the warning module includes:

[0040] A threshold comparison unit, connected to the validity analysis unit and the internal resistance analysis unit, for receiving the validity index E and the internal resistance change rate internal resistance change rate index r, and comparing them with a preset validity threshold E0 and an internal resistance change rate threshold r0;

[0041] When E < E0 or r > r0, a corresponding warning signal is generated;

[0042] A signal sending unit, connected to the threshold comparison unit, for sending the warning signal to relevant monitoring devices, operator terminals or remote monitoring centers.

[0043] On the other hand, the present invention provides an on-line monitoring method for a battery, including:

[0044] Step 1, preset various parameters, including basic parameters determined according to the battery specifications, coefficients based on experiments or estimations, and thresholds; complete the hardware connection and check to ensure that each module is correctly connected and working properly;

[0045] Step 2, continuously collect and integrate and transmit the voltage, current and temperature parameters of the battery during normal operation;

[0046] Step 3: Switch the operating state according to the cycle or instruction, collect and integrate the relevant voltage and current parameters of the transmission battery when it is alone with load;

[0047] Step 4: After receiving the parameters, respectively calculate the battery effectiveness index and internal resistance change rate index;

[0048] Step 5: Compare the calculated indicator with the threshold value. If there is any abnormality, generate and send a warning signal.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The present invention not only monitors conventional voltage, current and temperature parameters, but also accurately monitors the internal resistance of the battery; through the normal monitoring module and the voltage reduction monitoring module, comprehensive data is obtained under different operating conditions, which can more accurately reflect the actual working conditions of the battery;

[0051] The effectiveness analysis model of the present invention comprehensively considers multiple factors such as the voltage change, capacity, temperature, aging degree, self-discharge rate and charge-discharge efficiency of the battery under different operating conditions; through precise formula calculation, the effectiveness of the battery is comprehensively evaluated, which can more accurately reflect the actual performance of the battery in actual use and the effective power it can provide;

[0052] The internal resistance change rate analysis model accurately calculates the internal resistance change rate by comparing the internal resistance of the battery under different operating conditions and taking into account the influence of connection resistance and contact resistance. It can more accurately evaluate the health of the battery's internal structure and connections, and promptly discover performance problems caused by internal resistance changes.

[0053] Based on comprehensive data analysis and accurate threshold setting, the present invention can issue early warning signals in a timely and accurate manner; when the effectiveness index of the battery is lower than the set threshold or the internal resistance change rate exceeds the normal range, the system immediately activates the early warning mechanism;

[0054] The system adopts a modular design architecture, and each module is independent of each other but works together, so that when the system function is expanded or upgraded, a single module can be easily modified or replaced without affecting the operation of the entire system.

[0055] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0056] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0058] Figure 1 Schematic diagram of the structure of a battery online monitoring system provided by an embodiment of the present invention;

[0059] Figure 2 It is a flow chart of a battery online monitoring method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0060] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0061] Example 1

[0062] This embodiment provides a battery online monitoring system. Figure 1 ,include:

[0063] A normal monitoring module, which is connected to the battery pack and is used to continuously collect first operating parameters related to the battery when the battery is in normal operating state;

[0064] A voltage reduction monitoring module connected to the battery pack and used for continuously collecting a second operating parameter related to the battery when the battery is operating alone with a load;

[0065] A switching control module, which is electrically connected to the normal monitoring module, the voltage reduction monitoring module, the battery pack and the DC bus, is used to periodically switch the operating state of the battery and control the monitoring actions of the normal monitoring module and the voltage reduction monitoring module after switching;

[0066] A summary analysis module, which is connected to the normal monitoring module and the voltage reduction monitoring module, and is used to summarize the first operating parameter and the second operating parameter in a cycle, and analyze the battery effectiveness and internal resistance change rate;

[0067] The early warning module is connected to the summary analysis module and is used to generate corresponding early warning signals according to the analysis results.

[0068] The principle of the above embodiment is: through the normal monitoring module and the voltage reduction monitoring module, various parameters of the battery are collected under different operating conditions, covering basic parameters such as voltage, current, temperature, and related data under specific working conditions. The switching control module realizes the periodic switching of the battery operating state, so that the system can fully obtain the performance of the battery under different working conditions. The collected parameters are summarized in the summary analysis module, which uses a preset analysis model to comprehensively consider various factors such as temperature, aging, self-discharge, etc., and accurately calculates and analyzes the effectiveness and internal resistance change rate of the battery. Finally, the early warning module generates an early warning signal in time according to the results of the summary analysis module when it is found that the performance indicators of the battery exceed the preset normal range, so as to prompt relevant personnel to take corresponding measures. Through the collaborative work of various modules, the entire system realizes comprehensive and dynamic monitoring and accurate evaluation of the battery, ensuring the reliable operation and timely maintenance of the battery.

[0069] The beneficial effects of the above embodiments are: achieving comprehensive monitoring and accurate evaluation, enabling real-time warning and timely processing, improving maintenance efficiency and reducing costs, and adapting to different application scenarios.

[0070] In order to further optimize the above embodiment, the normal monitoring module includes:

[0071] The voltage acquisition unit is connected to the battery pack and the DC bus and is used to collect the bus voltage U when the battery is operating normally. n1 and the battery terminal voltage U n2 ;

[0072] The current collection unit is connected to the output line of the battery pack and is used to collect the output current I during normal operation. n ;

[0073] The temperature collection unit is installed on the surface of the battery pack to collect the temperature T of the battery pack. n ;

[0074] The data integration unit is connected to the voltage acquisition unit, the current acquisition unit and the temperature acquisition unit, and is used to integrate and package the collected voltage, current and temperature data to form a first operating parameter set.

[0075] It should be noted that the bus voltage and battery terminal voltage collected by the voltage acquisition unit are important parameters for evaluating the battery charging state and discharge capacity; the bus voltage reflects the voltage level of the entire DC bus system, while the battery terminal voltage directly reflects the battery output voltage; by monitoring these two voltages, it is possible to promptly detect whether the battery reaches the expected voltage normally during charging, and whether it can maintain a stable output voltage during discharge; for example, when the bus voltage is normal but the battery terminal voltage is too low, it may mean that there is a problem inside the battery, such as aging of the plate resulting in increased internal resistance, which affects the voltage output;

[0076] The output current collected by the current acquisition unit during normal operation can reflect the load condition and power supply capacity of the battery. By monitoring the magnitude and change trend of the current, it can be determined whether the battery is supplying power to the load within the normal range. If the current suddenly increases or decreases, it may be that the load has changed or the battery itself has a fault, such as a short circuit or open circuit.

[0077] The temperature acquisition unit is installed on the surface of the battery pack, and the collected temperature data is crucial for evaluating the performance and life of the battery. Because the performance of the battery is greatly affected by temperature, too high or too low temperature will affect its chemical reaction rate and internal resistance, and thus affect the battery's capacity, charge and discharge efficiency and life. For example, in a high temperature environment, the self-discharge rate of the battery will increase, the capacity may decrease, and the intensified internal chemical reaction may lead to accelerated corrosion of the plate. In a low temperature environment, the activity of the battery's active substances will decrease, and its discharge capacity will weaken, which may not be able to meet the load requirements.

[0078] In order to further optimize the above embodiment, the voltage reduction monitoring module includes:

[0079] The step-down voltage acquisition unit is connected between the battery pack and the DC bus and is used to collect the stepped-down bus voltage U when the battery is operating alone with load. d1 And the battery output voltage U d2 ;

[0080] The single load current acquisition unit is connected to the battery output line to collect the output current I of the battery when it is loaded alone. d ;

[0081] The step-down parameter integration unit is connected to the step-down voltage acquisition unit and the separate load current acquisition unit, and is used to integrate the collected step-down voltage and current data to form a second operation parameter set.

[0082] It should be noted that its function is the same as that of the above-mentioned normal monitoring module, the difference is that it is applied in different operating conditions.

[0083] In order to further optimize the above embodiment, the switching control module includes:

[0084] A state switching unit is connected to the battery pack, the DC bus, the normal monitoring module and the voltage reduction monitoring module, and is used to switch the operating state of the battery between normal operation and single load operation according to a preset cycle or system instruction;

[0085] A monitoring control unit is connected to the normal monitoring module, the voltage reduction monitoring module and the state switching unit, and is used to generate a feedback signal after the state switching unit completes the operation state switching, and send a control instruction to the normal monitoring module and the voltage reduction monitoring module according to the feedback signal to start or stop the corresponding monitoring action;

[0086] The protection unit is connected to the battery pack, the DC bus, the state switching unit and the monitoring control unit, and is used to protect the battery pack, the DC bus and related circuit equipment from damage caused by abnormal voltage and current during the switching control process.

[0087] It should be noted that the main function of the state switching unit is to switch the operating state of the battery; the battery is switched between the normal operating state and the single load operating state according to a preset cycle (for example, at regular intervals, such as 1 hour, 1 day, etc.) or according to system instructions (such as remote control instructions, triggered by system specific events, etc.); this switching enables the monitoring system to fully understand the performance of the battery under different working conditions; in the normal operating state, the battery may supply power to the load together with other power devices (such as chargers), or be in a floating charge state to maintain the power; in the single load operating state, the battery independently bears the load, and at this time, the changes in its voltage, current and other parameters under full load or near full load can be more clearly observed, which is of great significance for evaluating the actual power supply capacity and potential problems of the battery;

[0088] Relays or electronic switches can be used to switch the circuit. For example, a step-down silicon chain can be switched between the charger and the positive pole of the DC bus to allow the battery pack to carry the load alone, or a thyristor relay can be used to switch the connection mode between the battery and the DC bus and the load by controlling its conduction and cutoff. Upon receiving a switching instruction, the controller sends a control signal to the relay to change the contact state, thereby realizing the conversion of the operating state. At the same time, in order to ensure smooth and reliable switching, appropriate transition processing is required during the switching process, such as gradually increasing or decreasing the load to avoid instantaneous current shocks from damaging the battery and other equipment. A smooth transition of the current can be achieved by adding a buffer circuit (such as an LC circuit composed of an inductor and a capacitor) to the switching circuit.

[0089] The monitoring control unit plays a key role in coordinating and controlling the work of the monitoring module; when the state switching unit completes the operation state switching, the monitoring control unit will immediately generate a feedback signal; this feedback signal is used to confirm the completion of the switching operation on the one hand, and on the other hand, as a trigger signal, sends corresponding control instructions to the normal monitoring module and the voltage reduction monitoring module according to the switched operation state; for example, when switching to a single load operation state, the monitoring control unit sends a start instruction to the voltage reduction monitoring module to start collecting relevant parameters, and at the same time sends a stop instruction to the normal monitoring module (or adjusts its collection frequency and other parameters in some cases) to avoid unnecessary data collection and interference; through this precise control, it can ensure that the monitoring module collects valid data at the right time, improving monitoring efficiency and data accuracy;

[0090] The monitoring control unit can use a microcontroller (such as a single-chip microcomputer, ARM, etc.) to realize its functions; the microcontroller receives the switching completion signal through the communication interface (such as a serial port, SPI, etc.) with the state switching unit; then, according to the preset program logic and state information, the control instructions are sent to the normal monitoring module and the voltage reduction monitoring module through the corresponding output port; these instructions can be digital signals, which are transmitted to the control chip or circuit in the monitoring module through wired communication (such as RS-485, CAN bus, etc.), so as to realize the start and stop control of the monitoring action; at the same time, in order to ensure the accurate transmission and execution of the instructions, a verification and confirmation mechanism can be added to the communication protocol, such as waiting for the reply confirmation of the monitoring module after sending the instruction to ensure that the instruction has been correctly received and executed;

[0091] The protection unit is crucial in the switching control process. Its main purpose is to protect the battery pack, DC bus and related circuit equipment from damage caused by abnormal voltage and current. During the switching process of the operating state, due to the change of the circuit state, abnormal conditions such as overvoltage and overcurrent may occur. If these abnormal conditions are not handled, they will cause serious damage to the battery and other equipment, affecting their service life and performance, and may even cause safety accidents. The protection unit monitors the voltage and current signals in real time. Once an abnormality is found, it will immediately take corresponding protection measures, such as cutting off the circuit, starting the overvoltage protection device (such as varistor), overcurrent protection device (such as fuse, electronic fuse, etc.), so as to ensure the safe and stable operation of the entire system.

[0092] For voltage monitoring, a voltage sensor can be used to collect the voltage signal in the circuit in real time and transmit it to the comparison circuit of the protection unit; the comparison circuit compares the collected voltage with the preset normal voltage range, and triggers the protection action when the voltage exceeds the range; for example, when the voltage is too high, the connection between the battery and the busbar is cut off by controlling the relay, or the varistor connected in parallel in the circuit is started to absorb the overvoltage energy to protect the subsequent circuit; for current monitoring, a current sensor (such as a Hall current sensor) can be used to collect the current signal, which is sent to the comparison circuit after amplification and processing; when the current exceeds the set threshold, the overcurrent protection device is triggered, such as the fuse blowing or the electronic fuse cutting off the circuit, to prevent excessive current from damaging the equipment; at the same time, the protection unit can also be equipped with monitoring and alarm functions. When an abnormal situation is detected, in addition to taking protective measures, an alarm signal can also be sent to the monitoring system to remind the operation and maintenance personnel to deal with the problem in time.

[0093] In order to further optimize the above embodiment, the summary analysis module includes:

[0094] a parameter receiving unit connected to the data integration unit and the voltage reduction parameter integration unit, and configured to receive a first operating parameter set and a second operating parameter set;

[0095] An effectiveness analysis unit, connected to the parameter receiving unit, for calculating the effectiveness index E of the current battery according to the received parameters and a preset effectiveness analysis model;

[0096] The internal resistance analysis unit is connected to the parameter receiving unit and is used to calculate the internal resistance change rate index r of the current battery according to the received parameters and a preset internal resistance change rate analysis model.

[0097] Among them, the effectiveness analysis model is:

[0098]

[0099] Among them, E is the effectiveness index of the current battery; U n1 is the bus voltage during normal monitoring, U d1 is the bus voltage during voltage reduction monitoring; C is the rated capacity of the battery, which is determined by the battery specifications; k T is the temperature correction coefficient, and k T =1+i T *(T-25), T is the battery pack temperature T during this cycle n The average temperature, i T is the temperature proportionality coefficient, determined based on experiments, indicating the proportion of the average temperature deviation from the reference temperature on the battery performance. The reference temperature is set at 25 degrees Celsius. The temperature correction coefficient k T Used to reflect the impact of temperature on battery performance; aA is the battery aging coefficient, and a A =i T *y, y is the year of use of the battery, i T The annual aging coefficient is determined based on long-term tracking or aging mechanism estimation, indicating the proportion of the impact of the use year on the battery performance. The battery aging coefficient a A Used to reflect the impact of the use year on battery performance; s is the battery self-discharge rate, which is determined by the type of battery; t is the time of a monitoring cycle; η is the battery charge and discharge efficiency, which is determined according to the battery model; I n It is the output current during normal monitoring;

[0100] The effectiveness index E comprehensively evaluates the effectiveness of the battery based on the battery's voltage change, capacity, temperature, aging degree, self-discharge rate, and charge and discharge efficiency under different operating conditions;

[0101] The internal resistance change rate analysis model is:

[0102]

[0103] Among them, r is the internal resistance change rate index; is the battery internal resistance calculated during voltage reduction monitoring, U d2 is the battery output voltage during voltage reduction monitoring, I d is the output current during voltage reduction monitoring; is the battery internal resistance calculated during normal monitoring, U n2 is the battery terminal voltage during normal monitoring, I n is the output current during normal monitoring; (R c *l) is the connection resistance, where l is the length of the battery connection line, R c is the resistance length coefficient, which is determined based on experimental measurements and is used to reflect the contribution of the connection line per unit length to the resistance; {R ct *(1-k p )} is the contact resistance, k p is the contact pressure coefficient, which is estimated based on the contact pressure at the connection part. ct is the contact resistance pressure coefficient, indicating the contact pressure coefficient k p The proportion of the impact on contact resistance is determined based on experimental simulation and fitting;

[0104] The internal resistance change rate index r is obtained by comparing the internal resistance of the battery under different operating conditions and taking into account the influence of connection resistance and contact resistance, thereby evaluating the health of the battery's internal structure and connections.

[0105] It should be noted that the effectiveness analysis model and the internal resistance change rate analysis model can more comprehensively and accurately evaluate the performance and health status of the battery by comprehensively considering multiple influencing factors. Compared with the simple evaluation methods in the prior art, they have higher accuracy and reliability. The determination of the temperature proportionality coefficient and the annual aging proportionality coefficient is based on experimental measurements, long-term tracking data, or estimated according to the battery aging mechanism, and needs to be reasonably calibrated and adjusted according to the specific battery type and usage environment in actual applications. The consideration of the connection resistance and contact resistance makes the internal resistance analysis closer to the actual situation. In an actual system, the resistance of the connection line and the resistance of the contact part will affect the total internal resistance of the battery. By calculating separately and incorporating them into the internal resistance change rate analysis model, the health status of the internal structure and connection of the battery can be more accurately evaluated, and misjudgment caused by ignoring these factors can be avoided.

[0106] The design of the entire summary analysis module aims to provide a comprehensive, accurate, and real-time battery performance analysis tool, providing strong support for subsequent early warning and maintenance decisions. By real-time monitoring and analyzing the effectiveness index and the internal resistance change rate index, potential problems of the battery can be detected in a timely manner, corresponding measures can be taken to improve the reliability and stability of the battery system, and reduce the maintenance cost and failure risk.

[0107] To further optimize the above embodiments, the early warning module includes:

[0108] A threshold comparison unit, connected to the effectiveness analysis unit and the internal resistance analysis unit, is used to receive the effectiveness index E and the internal resistance change rate index r, and compare them with the preset effectiveness threshold E0 and the internal resistance change rate threshold r0.

[0109] When E < E0 or r > r0, a corresponding early warning signal is generated.

[0110] A signal sending unit, connected to the threshold comparison unit, is used to send the early warning signal to relevant monitoring devices, operator terminals, or remote monitoring centers.

[0111] It should be noted that the setting of the effectiveness threshold and the internal resistance change rate threshold should be based on the following aspects:

[0112] I. The specifications and performance parameters of the battery

[0113] 1. Rated capacity

[0114] Batteries with different rated capacities have different performance and carrying capacity in actual applications. Generally speaking, large-capacity batteries may be able to withstand greater load changes and wider performance fluctuations to a certain extent. For example, for a high-capacity battery pack used as a backup power supply for a large data center, its effectiveness threshold can be set relatively lower (but still within a safe range) because it has a certain degree of redundancy in its design to cope with some minor performance degradation. Small-capacity batteries used for small devices may require higher effectiveness guarantees, and the threshold setting is relatively high.

[0115] When considering the internal resistance change rate threshold, the internal resistance change of large-capacity batteries may be relatively small due to the relatively complex internal structure and large electrode surface area. Therefore, the internal resistance change rate threshold can be relatively loose; while the impact of the internal resistance change on the performance of small-capacity batteries may be more significant, and the threshold should be set more strictly.

[0116] 2. Charge and discharge efficiency

[0117] A battery with high charge and discharge efficiency has less loss during the energy conversion process and can provide energy to the load more efficiently. When setting the effectiveness threshold, it can be determined in combination with its charge and discharge efficiency. For example, if a battery has a high charge and discharge efficiency, then under the same load conditions, its effectiveness index is relatively good, and the threshold can be appropriately increased. Conversely, the threshold of a battery with low charge and discharge efficiency should be lowered to more sensitively monitor its performance changes.

[0118] The charge and discharge efficiency also has an impact on the internal resistance change rate threshold. Low charge and discharge efficiency may be related to increased internal resistance. Therefore, when the battery charge and discharge efficiency is low, the internal resistance change rate threshold should be set lower to promptly detect internal resistance problems that may lead to reduced efficiency.

[0119] 3. Design life

[0120] The design life of the battery is an important reference factor. The performance of the battery nearing the end of its design life is more likely to decline, and both the effectiveness and internal resistance changes may be more obvious. Therefore, for batteries nearing the end of their life, the effectiveness threshold should be lowered and the internal resistance change rate threshold should be increased to strengthen monitoring and timely detect possible faults. For batteries that are newly put into use or have a long service life, the threshold can be set relatively loosely, but it should also be reasonably adjusted according to actual conditions.

[0121] 2. Actual Application Scenarios and Load Requirements

[0122] 1. Key application scenarios

[0123] In some critical application scenarios that require extremely high continuity of power supply, such as emergency equipment in hospitals and core communication equipment in communication base stations, the reliability of batteries is crucial. In this case, the effectiveness threshold should be set high to ensure that the battery can provide sufficient effective power to maintain the operation of the equipment at any time. The internal resistance change rate threshold should also be low, because even a small change in internal resistance may affect the power supply stability of these critical devices.

[0124] For example, in the backup power supply system of a hospital operating room, the effectiveness threshold may need to be set above 95%, and the internal resistance change rate threshold may be set within 10% (hypothetical values, to be determined based on actual conditions) to ensure that in emergency situations such as power outages, the battery can stably and reliably power surgical equipment, and any potential problems that may affect power supply can be monitored and warned in a timely manner;

[0125] 2. Non-critical application scenarios

[0126] For some non-critical application scenarios, such as backup power supply for lighting in general office places, the requirements for batteries are relatively low; the effectiveness threshold can be appropriately lowered and the internal resistance change rate threshold can be increased; for example, the effectiveness threshold can be set at around 80%, and the internal resistance change rate threshold can be set at around 20% (hypothetical value, to be determined according to actual conditions); as long as the battery can meet the basic backup power supply needs to a certain extent, there is no need for strict monitoring standards like those in critical scenarios, so as to balance the monitoring cost and actual needs;

[0127] 3. Load characteristics

[0128] Different loads have different performance requirements for batteries. If the load has large current fluctuations or instantaneous high power requirements, the battery needs to have better performance to cope with it. In this case, the effectiveness threshold should be set higher to ensure that the battery can effectively supply power under high loads. At the same time, the internal resistance change rate threshold should be lower, because a small change in internal resistance may cause a large voltage fluctuation under a large current load, affecting the normal operation of the equipment.

[0129] For example, for some backup power supplies for equipment with frequently started motors, a large current is required when the motor is started, and the change in the internal resistance of the battery will have a greater impact on the starting performance; at this time, the internal resistance change rate threshold should be set more strictly to ensure the reliability of the battery under high current conditions such as motor starting;

[0130] 3. Historical Operation Data and Experience

[0131] 1. Historical data of batteries of the same type

[0132] By analyzing the historical data of a large number of batteries of the same type in actual operation, we can understand the performance change trend, effectiveness range and internal resistance change law of these batteries in normal use; based on the statistical analysis of these historical data, we can determine a reasonable effectiveness threshold and internal resistance change rate threshold range; for example, if historical data shows that under normal operation of a certain type of battery, the effectiveness usually fluctuates between 85% and 95%, and the internal resistance change rate generally does not exceed 15% within a certain period of time, then the effectiveness threshold can be set between 80% and 90% (the specific value is determined according to actual needs and safety margins), and the internal resistance change rate threshold can be set between 10% and 20%;

[0133] 2. Early operation data of the battery in this system

[0134] For the battery monitoring system currently in use, the operation data accumulated in the early stage also has important reference value; the operation of the battery in this system in the past period of time can be analyzed to observe the actual performance of its effectiveness and internal resistance change rate; if it is found that the performance of the battery has a certain downward trend or large fluctuations in certain time periods, the threshold can be adjusted accordingly; for example, if in the past few months, it is found that the effectiveness of the battery has gradually dropped to about 85%, and the internal resistance change rate has an increasing trend, then it can be considered to lower the effectiveness threshold (such as setting it to 82%), and at the same time lower the internal resistance change rate threshold (such as setting it to 12%), so as to discover potential problems earlier and deal with them;

[0135] 3. Industry experience and standards

[0136] Referencing the relevant experience and standards of the battery industry is also an important basis for setting thresholds. The industry may have some recommended values ​​or experience ranges for battery thresholds of different types and application scenarios. For example, some industry standards may stipulate that in a specific application scenario, the battery's effectiveness threshold should not be lower than a certain value, and the internal resistance change rate threshold should be within a certain range. When setting thresholds, you can combine these industry experiences and standards, and make appropriate adjustments based on the actual characteristics of your own system to ensure the rationality and applicability of the thresholds.

[0137] 4. Environmental factors

[0138] 1. Temperature

[0139] Temperature has a significant impact on the performance of batteries. In high temperature environments, the internal chemical reaction rate of batteries is accelerated, self-discharge increases, capacity may decrease, and internal resistance may also change. Therefore, in high temperature environments, the effectiveness threshold should be appropriately lowered and the internal resistance change rate threshold should be appropriately increased. On the contrary, in low temperature environments, the activity of active substances in batteries decreases, and the discharge capacity weakens. A higher effectiveness threshold may be required to ensure its performance at low temperatures. For example, in high temperature areas (such as summer temperatures often exceeding 35°C), the effectiveness threshold can be reduced by 5%-10% and the internal resistance change rate threshold can be increased by 5%-10%. In low temperature areas (such as winter temperatures often below 0°C), the effectiveness threshold can be increased by 5%-10%.

[0140] 2. Humidity

[0141] High humidity environment may cause corrosion of battery shell, rust at joints and other problems, thus affecting its performance and internal resistance. If the humidity of the system operating environment is high, the impact of these factors on the threshold needs to be considered. Generally speaking, the effectiveness threshold can be appropriately lowered and the internal resistance change rate threshold can be increased to strengthen the monitoring of batteries in high humidity environments. For example, if the ambient humidity is above 80% for a long time, the effectiveness threshold can be lowered by 3%-5% and the internal resistance change rate threshold can be increased by 3%-5% to promptly detect potential problems caused by humidity.

[0142] 5. Balance between maintenance cost and risk

[0143] 1. Maintenance Cost

[0144] Lower threshold settings can detect potential battery problems more promptly, but may also lead to more false alarms and unnecessary maintenance operations, thereby increasing maintenance costs; therefore, when setting thresholds, it is necessary to consider the balance between maintenance costs and monitoring accuracy; if the maintenance cost is high, such as requiring professionals to frequently visit the site for inspection and maintenance, then the threshold can be appropriately increased while ensuring safety to reduce false alarms and unnecessary maintenance times; but if the maintenance cost is relatively low, or the system reliability requirements are extremely high, even if some increased maintenance costs are acceptable, then a lower threshold can be set to more strictly monitor battery performance;

[0145] 2. Risk tolerance

[0146] Different users or application scenarios have different risk tolerances. For some users with low risk tolerance, such as financial data centers, even a brief power failure may cause huge losses. Therefore, it is necessary to set a lower effectiveness threshold and a lower internal resistance change rate threshold to minimize the risk of battery failure. For some users with relatively high risk tolerance, the thresholds can be appropriately increased to a certain extent to reduce unnecessary warnings and maintenance work, but it is also necessary to ensure that they are within an acceptable risk range. For example, a financial data center may set the effectiveness threshold above 90% and the internal resistance change rate threshold within 5%. For some ordinary industrial production sites, if a brief power outage has little impact on production, the effectiveness threshold can be set between 80%-85%, and the internal resistance change rate threshold can be set between 10%-15% (the specific values ​​need to be evaluated and determined based on actual conditions).

[0147] Example 2

[0148] This embodiment provides a battery online monitoring method. Figure 2 ,include:

[0149] Step 1: Pre-set various parameters, including basic parameters determined according to battery specifications, coefficients based on experiments or estimates, and thresholds; complete hardware connection and check to ensure that each module is correctly connected and working properly;

[0150] Step 2: continuously collect and integrate the voltage, current and temperature parameters of the battery during normal operation;

[0151] Step 3: Switch the operating state according to the cycle or instruction, collect and integrate the relevant voltage and current parameters of the transmission battery when it is alone with load;

[0152] Step 4: After receiving the parameters, respectively calculate the battery effectiveness index and internal resistance change rate index;

[0153] Step 5: Compare the calculated indicator with the threshold value. If there is any abnormality, generate and send a warning signal.

[0154] It should be noted that the parameter setting and hardware connection check in step 1 lay the foundation for subsequent accurate monitoring and evaluation. In steps 2 and 3, a variety of key parameters of the battery under normal operation and single load operation are fully collected, including conventional parameters such as voltage, current and temperature, as well as specific parameters when single load is carried. These rich data provide strong support for the accurate calculation of effectiveness index and internal resistance change rate index, and can more comprehensively and accurately reflect the performance of the battery. Compared with traditional methods, it avoids the performance evaluation deviation caused by incomplete or inaccurate data, and can timely discover potential problems of the battery, such as internal aging, poor connection, etc., providing a reliable basis for maintenance and management. Steps 4 and 5 realize real-time monitoring and early warning of battery performance. By comparing the calculated effectiveness index and internal resistance change rate index with the preset threshold, it can timely and accurately determine whether the battery has abnormalities. Once an abnormality is found, an early warning signal is immediately generated and sent, so that relevant personnel can quickly take measures to deal with it, avoiding system failures or accidents caused by battery failures that are not discovered in time. This real-time warning mechanism greatly improves the reliability and stability of the system, reduces losses caused by battery problems, and ensures the continued normal operation of related equipment.

[0155] The overall process of this monitoring method improves the efficiency of battery maintenance and management. The preliminary preparation work in step one ensures the correct setting of the system and the normal operation of the hardware, reducing monitoring errors and failures caused by configuration errors or hardware failures. The continuous and specific parameter collection under step two and step three, as well as the indicator calculation in step four, realize the dynamic tracking and analysis of battery performance, so that maintenance personnel can understand the status change trend of the battery in a timely manner. When an abnormality occurs, the early warning signal can quickly locate the problem, and targeted maintenance and repair can be carried out, saving time and cost for troubleshooting and improving the efficiency and quality of maintenance work.

[0156] The steps in the method can be flexibly adjusted and configured according to actual needs. For example, the parameter settings in step one can be customized according to the specifications and application scenarios of different batteries, and the threshold settings can adapt to different safety requirements and performance standards. The acquisition cycle of steps two and three can be adjusted according to the importance of the system and the load changes. For key application scenarios, the cycle can be shortened to increase the monitoring frequency. For relatively stable scenarios, the cycle can be appropriately extended to reduce the system burden. This flexibility enables the monitoring method to be widely used in various fields and scenarios, such as power systems, communication base stations, data centers, etc., meeting the diverse needs of different users for battery monitoring.

[0157] Through real-time monitoring and early warning, battery problems can be discovered and handled in a timely manner, avoiding the accumulation and deterioration of problems, thereby extending the service life of the battery. At the same time, accurate performance evaluation and effective maintenance management measures help to maintain the good operating condition of the battery and improve the reliability of the entire system. In key areas such as power systems, reliable battery systems are important factors in ensuring the continuity and stability of power supply. The implementation of this monitoring method can effectively improve the overall reliability of the system and reduce the risks of power outages caused by battery failures.

[0158] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery online monitoring system, characterized in that: include: A normal monitoring module, which is connected to the battery pack and is used to continuously collect first operating parameters related to the battery when the battery is in normal operating state; A voltage reduction monitoring module connected to the battery pack and used for continuously collecting a second operating parameter related to the battery when the battery is operating alone with a load; A switching control module, which is electrically connected to the normal monitoring module, the voltage reduction monitoring module, the battery pack and the DC bus, and is used to periodically switch the operating state of the battery and control the monitoring actions of the normal monitoring module and the voltage reduction monitoring module after switching; A summary analysis module, connected to the normal monitoring module and the voltage reduction monitoring module, for summarizing the first operating parameter and the second operating parameter in a cycle, and analyzing the battery effectiveness and internal resistance change rate; The early warning module is connected to the summary analysis module and is used to generate a corresponding early warning signal according to the analysis results.

2. A battery online monitoring system according to claim 1, characterized in that: The normal monitoring module includes: The voltage acquisition unit is connected to the battery pack and the DC bus and is used to collect the bus voltage U when the battery is operating normally. n1 and the battery terminal voltage U n2 ; The current collection unit is connected to the output line of the battery pack and is used to collect the output current I during normal operation. n ; The temperature collection unit is installed on the surface of the battery pack to collect the temperature T of the battery pack. n ; The data integration unit is connected to the voltage acquisition unit, the current acquisition unit and the temperature acquisition unit, and is used to integrate and package the collected voltage, current and temperature data to form a first operating parameter set.

3. A battery online monitoring system according to claim 2, characterized in that: The voltage reduction monitoring module comprises: The step-down voltage acquisition unit is connected between the battery pack and the DC bus and is used to collect the stepped-down bus voltage U when the battery is operating alone with load. d1 And the battery output voltage U d2 ; The single load current acquisition unit is connected to the battery output line to collect the output current I of the battery when it is loaded alone. d ; The step-down parameter integration unit is connected to the step-down voltage acquisition unit and the separate load current acquisition unit, and is used to integrate the collected step-down voltage and current data to form a second operation parameter set.

4. A battery online monitoring system according to claim 3, characterized in that: The switching control module comprises: A state switching unit, connected to the battery pack, the DC bus, the normal monitoring module and the voltage reduction monitoring module, and used to switch the operating state of the battery between normal operation and single load operation according to a preset cycle or system instruction; A monitoring control unit, connected to the normal monitoring module, the voltage reduction monitoring module and the state switching unit, for generating a feedback signal after the state switching unit completes the operation state switching, and sending a control instruction to the normal monitoring module and the voltage reduction monitoring module according to the feedback signal to start or stop the corresponding monitoring action; The protection unit is connected to the battery pack, the DC bus, the state switching unit and the monitoring control unit, and is used to protect the battery pack, the DC bus and related circuit equipment from damage caused by abnormal voltage and current during the switching control process.

5. A battery online monitoring system according to claim 4, characterized in that: The summary analysis module includes: a parameter receiving unit, connected to the data integration unit and the voltage reduction parameter integration unit, and configured to receive a first operating parameter set and a second operating parameter set; An effectiveness analysis unit, connected to the parameter receiving unit, for calculating the effectiveness index E of the current battery according to the received parameters and a preset effectiveness analysis model; The internal resistance analysis unit is connected to the parameter receiving unit and is used to calculate the internal resistance change rate index r of the current battery according to the received parameters and a preset internal resistance change rate analysis model.

6. A battery online monitoring system according to claim 5, characterized in that: The effectiveness analysis model is: Among them, E is the effectiveness index of the current battery; U n1 is the bus voltage during normal monitoring, U d1 is the bus voltage during voltage reduction monitoring; C is the rated capacity of the battery, which is determined by the battery specifications; k T is the temperature correction coefficient, and k T =1+i T *(T-25), T is the battery pack temperature T during this cycle n The average temperature, i T is the temperature proportionality coefficient, determined based on experiments, indicating the proportion of the effect of the average temperature deviation from the reference temperature on the battery performance. The reference temperature is set to 25 degrees Celsius. The temperature correction coefficient k T Used to reflect the impact of temperature on battery performance; a A is the battery aging coefficient, and a A =i T *y, y is the year of use of the battery, i T The annual aging coefficient is determined based on long-term tracking or aging mechanism estimation, indicating the proportion of the impact of the use year on the battery performance. A Used to reflect the impact of the use year on battery performance; s is the battery self-discharge rate, which is determined by the type of battery; t is the time of a monitoring cycle; η is the battery charge and discharge efficiency, which is determined according to the battery model; I n It is the output current during normal monitoring; The effectiveness index E comprehensively evaluates the effectiveness of the battery based on the voltage change, capacity, temperature, aging degree, self-discharge rate, and charge and discharge efficiency of the battery under different operating conditions.

7. A battery online monitoring system according to claim 6, characterized in that: The internal resistance change rate analysis model is: Among them, r is the internal resistance change rate index; is the battery internal resistance calculated during voltage reduction monitoring, U d2 is the battery output voltage during voltage reduction monitoring, I d is the output current during voltage reduction monitoring; is the battery internal resistance calculated during normal monitoring, U n2 is the battery terminal voltage during normal monitoring, I n is the output current during normal monitoring; (R c *l) is the connection resistance, where l is the length of the battery connection line, R c is the resistance length coefficient, which is determined based on experimental measurements and is used to reflect the contribution of the connection line per unit length to the resistance; {R ct *(1-k p )} is the contact resistance, k p is the contact pressure coefficient, which is estimated based on the contact pressure at the connection part. ct is the contact resistance pressure coefficient, indicating the contact pressure coefficient k p The proportion of the impact on contact resistance is determined based on experimental simulation and fitting; The internal resistance change rate index r is obtained by comparing the internal resistance of the battery under different operating states and considering the influence of the connection resistance and contact resistance, so as to evaluate the health status of the internal structure and connection of the battery.

8. A battery online monitoring system according to claim 7, characterized in that: The warning module includes: A threshold comparison unit, connected to the effectiveness analysis unit and the internal resistance analysis unit, for receiving the effectiveness index E and the internal resistance change rate index r, and comparing them with the preset effectiveness threshold E0 and internal resistance change rate threshold r0; When E < E0 or r > r0, a corresponding warning signal is generated; A signal sending unit, connected to the threshold comparison unit, for sending the warning signal to relevant monitoring devices, operator terminals or remote monitoring centers.

9. A battery online monitoring method, based on the monitoring system according to claims 1-8, characterized in that: It includes the following steps: Step 1, preset various parameters, including basic parameters determined according to the battery specifications, coefficients based on experiments or estimations, and thresholds; Complete the hardware connection and check to ensure that each module is correctly connected and working properly; Step 2, continuously collect and integrate and transmit the voltage, current and temperature parameters of the battery during normal operation; Step 3, switch the operating state according to the cycle or instruction, and collect and integrate and transmit the relevant voltage and current parameters of the battery when it is loaded alone; Step 4, after receiving the parameters, calculate the effectiveness index and internal resistance change rate index of the battery respectively; Step 5, compare the calculated index with the threshold, and if it is abnormal, generate and send a warning signal.

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