KR20210079261A - Abnormal condition detection system using battery voltage data - Google Patents

Abstract

An embodiment of the present invention relates to an abnormal condition pre-detection system. The technical task to be solved is to provide an abnormal state pre-detection system using battery voltage data, for detecting omens related to the abnormality of a battery using various voltage data of the battery and warning a user or stopping system operation, thereby improving system safety. In accordance with the present invention, disclosed is an abnormal condition pre-detection system using battery voltage data, comprising: a voltage sensing unit for sensing voltage of each battery cell and providing battery voltage data for each battery cell; a voltage deviation calculation unit for calculating a voltage deviation (Va) between each battery cell from the battery voltage data; a voltage change calculation unit for calculating a voltage change (Vb) of each battery cell over time of each battery cell from the battery voltage data; a voltage calculation unit including a voltage deviation change calculation unit for calculating a change (Vc) of the voltage deviation of each battery cell over time of each battery cell from the battery voltage data; and an action signal output unit for outputting a system action signal by comparing the voltage deviation (Va), the voltage change (Vb), or the change (Vc) of the voltage deviation with a reference value.

Description

Abnormal condition detection system using battery voltage data

An embodiment of the present invention relates to an abnormal state pre-detection system using battery voltage data.

In general, an energy storage system (ESS: Energy Storage System) stores energy produced from solar power, wind power, etc., which are new and renewable energy markets, in a storage device (eg, a battery), and supplies electricity at a necessary time to provide power efficiency device to improve

Such energy storage devices include a battery, a Power Conversion System (PCS, performing an AC-DC conversion function and a power distribution function), and an EMS (Energy Management System, which operates and manages the entire ESS system), and the like. Here, voltage, temperature, etc. are monitored and managed by a battery management system (BMS), and the BMS exchanges necessary information with the PCS and/or EMS.

On the other hand, recently, batteries include secondary batteries such as lithium ion batteries and lithium polymer batteries, and since the main material of these secondary batteries is lithium, which is unstable in air, securing safety such as preventing battery deterioration, ignition or explosion is paramount. It is important.

However, in the conventional ESS, when the voltage or temperature of the battery is out of the standard range, the BMS, PCS, and/or EMS operate only to stop the charging/discharging of the battery, performing a system warning, or stopping the operation of the system. By doing so, there was a problem that not only the safety of the ESS was low, but also a fire occurred in the ESS. In other words, the safety of the ESS can be further improved if a warning is given to the system or the operation of the system is stopped by detecting a precursor phenomenon in advance before the voltage or temperature exceeds the standard range due to a battery abnormality. No technology has been developed to prevent problems that may arise in the future by detecting a precursor phenomenon in advance when a battery is abnormal.

The above-described information disclosed in the background technology of the present invention is only for improving the understanding of the background of the present invention, and thus may include information that does not constitute the prior art.

A problem to be solved according to an embodiment of the present invention is a battery voltage capable of improving system safety by detecting a precursor phenomenon related to an abnormality of a battery using various voltage data of the battery, and warning the user or stopping the system operation. An object of the present invention is to provide a system for detecting anomalies in advance using data.

An abnormal state pre-detection system using battery voltage data according to an embodiment of the present invention includes: a voltage sensing unit for detecting voltages of a plurality of battery cells and providing battery voltage data for each of the plurality of battery cells; a voltage deviation calculator for calculating a voltage deviation (Va) between each battery cell from the battery voltage data; a voltage change calculator for calculating a voltage change (Vb) of each battery cell according to time of each battery cell from the battery voltage data; A voltage for calculating the ratio of the change (Vc) of the voltage deviation of each battery cell with the lapse of time of each battery cell from the battery voltage data and the change (Vc) of the voltage deviation with respect to the reference value of the voltage change (Vb) a voltage calculator including a deviation change calculator; and comparing the voltage deviation (Va), the voltage change (Vb), the change in voltage deviation (Vc), and the ratio of the change in voltage deviation (Vc) to a reference value of the voltage change (Vb) with a reference value. It may include an action signal output unit for outputting the action signal.

The system action signal of the action signal output unit is a system warning signal to analyze the detailed battery operation data to determine whether an actual abnormality has occurred, a system danger signal to take action on the checked abnormality, or a system to shut down the system It may be a shutdown signal.

A reference value set for outputting the system shutdown signal may be higher than a reference value set for outputting the system warning signal and the system danger signal.

The voltage calculator may operate in an SOC±10% section and/or a preset voltage section based on a time of entering a constant voltage charging section during charging of the battery cell.

The voltage calculator may operate in a section of 5% to 30% of the remaining amount SOC and/or a section of a preset voltage when the battery cell is discharged.

The plurality of battery cells may include battery cells connected in series or battery cells connected in parallel.

An embodiment of the present invention detects a precursor phenomenon related to a battery abnormality using various voltage data of the battery, and warns the user or stops the system operation, thereby improving system safety by using battery voltage data. A detection system is provided.

1 is a schematic diagram showing the configuration of a general ESS system.
2A and 2B are schematic diagrams illustrating a configuration example of a battery used in an abnormal state pre-detection system using battery voltage data according to an embodiment of the present invention.
3 is a block diagram illustrating the configuration of an abnormal state pre-detection system using battery voltage data according to an embodiment of the present invention.
4 is a block diagram illustrating the configuration of a voltage calculation unit and an action signal output unit in the abnormal state pre-detection system using battery voltage data according to an embodiment of the present invention.
5 is a graph illustrating a change in battery voltage and an abnormality determination position for explaining the operation of the abnormal state pre-detection system using battery voltage data according to an embodiment of the present invention.
6A and 6B are graphs and tables illustrating an example of a change in voltage of a battery for explaining the operation of an abnormal state pre-detection system using battery voltage data according to an embodiment of the present invention.
7 is a table illustrating an example of a voltage change of a battery for explaining the operation of the abnormal state pre-detection system using battery voltage data according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Examples of the present invention are provided to more completely explain the present invention to those of ordinary skill in the art, and the following examples may be modified in various other forms, and the scope of the present invention is as follows It is not limited to an Example. Rather, these examples are provided so that this disclosure will be more thorough and complete, and will fully convey the spirit of the invention to those skilled in the art.

In addition, in the following drawings, the thickness or size of each layer is exaggerated for convenience and clarity of description, and the same reference numerals in the drawings refer to the same elements. As used herein, the terms “or” and “and/or” include any one and any combination of one or more of those listed items. In addition, in the present specification, "connected" means not only when member A and member B are directly connected, but also when member A and member B are indirectly connected by interposing member C between member A and member B. do.

The terminology used herein is used to describe specific embodiments, not to limit the present invention. As used herein, the singular forms may include the plural forms unless the context clearly dictates otherwise. Also, as used herein, “comprise, include” and/or “comprising, including” refer to the recited shapes, numbers, steps, actions, members, elements, and/or groups thereof. It specifies the presence and does not exclude the presence or addition of one or more other shapes, numbers, movements, members, elements and/or groups.

Although the terms first, second, etc. are used herein to describe various members, parts, regions, layers and/or parts, these members, parts, regions, layers, and/or parts are limited by these terms so that they It is self-evident that These terms are used only to distinguish one member, component, region, layer or portion from another region, layer or portion. Accordingly, a first member, component, region, layer, or portion described below may refer to a second member, component, region, layer or portion without departing from the teachings of the present invention.

1 is a schematic diagram showing the configuration of a general ESS system.

As shown in FIG. 1 , the ESS system receives and stores energy from a renewable energy source, and for this, a battery having a BMS, PCS, and EMS may be included. BMS is a device that controls the state of the battery. It monitors the voltage, temperature, and charge/discharge status of the battery and regulates the charging/discharging level between unit battery cells in the module so that the cell balancing, overcharge prevention for battery safety, and overdischarge. It performs protection functions such as power outage protection, and also blocks the main switch in case of overcurrent or short circuit through the protection circuit, and also serves to communicate with PCS and EMS. In some examples, the battery may include a lithium ion battery, a lithium iron phosphate battery, a lithium polymer battery, or a lithium metal battery. The PCS can receive electrical energy from a renewable energy source or grid and convert the characteristics of electricity (AC/DC, voltage, frequency, etc.) to charge the battery or release the energy stored in the battery to the grid. The EMS (or PMS) may include an operating system for monitoring/controlling the states of the battery and the PCS, and for integrated monitoring and controlling the ESS in a control center or the like.

2A and 2B are schematic diagrams illustrating a configuration example of a battery used in an abnormal state pre-detection system using battery voltage data according to an embodiment of the present invention.

As shown in FIG. 2A , the battery 10 referred to in the abnormal state pre-detection system according to an embodiment of the present invention may include a configuration in which a plurality of battery cells are connected in parallel. In some examples, battery cells S11, S12, S13, and S14 are connected in parallel to form a first bank S1, and battery cells S21, S22, S23, and S24 are connected in parallel to form a second bank S2. and battery cells S31, S32, S33, and S34 are connected in parallel to form a third bank S3, and battery cells S41, S42, S43, and S44 are connected in parallel to form a fourth bank S4. have. Here, the first bank S1 to the fourth bank S4 may be connected in series. Also, as shown in FIG. 2B , the battery 10 referred to in the abnormal state pre-detection system according to the embodiment of the present invention may include a configuration in which a plurality of battery cells are connected in series. In some examples, the first battery cell S1 , the second battery cell S2 , the third battery cell S3 , and the fourth battery cell S4 may be connected in series.

3 is a block diagram illustrating the configuration of an abnormal state pre-detection system 100 using battery voltage data according to an embodiment of the present invention, and FIG. 4 is an abnormal state dictionary using battery voltage data according to an embodiment of the present invention. It is a block diagram showing the configuration of the voltage calculation unit 120 and the action signal output unit 130 of the detection system 100 .

As shown in FIG. 3 , the abnormal state pre-detection system 100 according to an embodiment of the present invention may include a voltage sensing unit 110 , a voltage calculation unit 120 , and an action signal output unit 130 . .

In some examples, the abnormal state pre-detection system 100 according to an embodiment of the present invention may further include an SOC estimator 140 , a time estimator 150 , and/or a reference value storage unit 160 .

The voltage sensing unit 110 may sense a voltage of each of the plurality of battery cells, and may provide battery voltage data for each of the plurality of battery cells to the voltage calculator 120 . For example, referring back to FIG. 2A , the voltage sensing unit 110 senses the voltages of the first bank S1 to the second bank S4 , respectively, and converts them into battery voltage data to calculate the voltage calculation unit 120 . can be provided to As another example, referring back to FIG. 2B , the voltage sensing unit 110 senses the voltages of the first battery cells S1 to the fourth battery cells S4, respectively, and converts them into battery voltage data to calculate the voltage. 120) can be provided.

The voltage calculator 120 may include a voltage deviation calculator 121 , a voltage change calculator 122 , and a voltage deviation change calculator 123 as shown in FIGS. 3 and 4 .

The voltage deviation calculator 121 may calculate a voltage deviation Va between each battery cell from the battery voltage data provided from the voltage sensing unit 110 , and provide it to the action signal output unit 130 . The voltage change calculator 122 calculates a voltage change (Vb) of each battery cell over time from the battery voltage data provided from the voltage sensing unit 110 and/or the voltage deviation calculator 121 . and may provide this to the action signal output unit 130 . The voltage deviation change calculator 123 calculates each battery according to the lapse of time of each battery cell from the battery voltage data provided from the voltage sensing unit 110 , the voltage deviation calculator 121 , and/or the voltage change calculator 122 . The voltage deviation change Vc of the cell may be calculated and provided to the action signal output unit 130 .

The action signal output unit 130 outputs a system action signal when the voltage deviation (Va), the voltage change (Vb) and/or the voltage deviation change (Vc) provided from the voltage calculator 120 is out of a preset reference value. can do.

In some examples, the system action signal output from the action signal output unit 130 may include a system warning signal, a system danger signal, and/or a system shutdown signal.

In some examples, the system warning signal may include a signal to analyze battery operation detailed data to determine whether an actual abnormality has occurred, which may be provided to the EMS. Accordingly, the EMS may visually or audibly notify the manager of this state through the system screen.

In some examples, the system hazard signal may include a signal to take action on the checked anomaly, which may be provided to the EMS. Accordingly, the EMS may visually or audibly notify the manager of this state through the system screen.

In some examples, the system shutdown signal may include a signal to shut down the ESS system for any cause to cease use. This system shutdown signal may be provided to the BMS, PCS, and/or EMS, so that the BMS, PCS and/or EMS may turn off the main switch to completely stop charging and discharging of the battery cells. Of course, the system shutdown information may be provided to the administrator visually or audibly through the EMS system screen.

The SOC estimator 140 may estimate the remaining capacity of the battery cell based on the voltage information provided from the voltage sensing unit 110 , and provide it to the voltage calculator 120 . In some examples, the SOC estimator 140 does not use the voltage sensing unit 110 and calculates the SOC estimated through another algorithm (eg, Kalman filter, screen, OCV, or other types of calculation information). (120) may be provided.

The time estimator 150 may estimate the usage time of the ESS system and provide it to the voltage calculator 120 . In some examples, the time estimator 150 may estimate the use date and/or the number of charge/discharge cycles of the ESS system and provide it to the voltage calculator 120 .

The reference value storage unit 160 stores in advance the reference value for the voltage deviation Va, the reference value for the voltage change Vb, and/or the reference value for the voltage deviation change Vc, and stores the reference value in the voltage calculation unit 120. can provide

In this way, the embodiment of the present invention detects a precursor phenomenon related to a battery abnormality using various voltage data of the battery, and warns an administrator or user or stops the system operation, thereby improving system safety. It is possible to provide the abnormal state pre-detection system 100 using data.

5 is a graph illustrating a change in battery voltage and an abnormality determination position for explaining the operation of the abnormal state pre-detection system 100 using battery voltage data according to an embodiment of the present invention. In FIG. 5 , the X axis may mean elapsed time, and the Y axis may mean voltage. In addition, the elapsed time of the X-axis may be divided into constant current (CC) charge, constant voltage (CV) charge, pause, and discharge.

As shown in FIG. 5 , the battery voltage gradually increases with time in the CC charging section, and can maintain a constant value despite the lapse of time in the CV charging section and the idle section, and gradually increases over time in the discharging section can decrease.

In some examples, the abnormal state pre-detection system 100 according to an embodiment of the present invention does not continuously calculate the voltage using the sensed battery voltage, but, for example, calculates the voltage in approximately two areas over time. can be done

In some examples, the voltage calculator 120 may operate in the SOC±10% interval based on the time of entering the constant voltage charging interval during charging of the battery cell. In other examples, the voltage calculator 120 may operate in the interval of 5% to 30% of the remaining amount SOC when the battery cell is discharged. Here, the voltage calculator 120 may obtain the SOC remaining amount from the SOC estimator 140 , but the present invention is not limited thereto.

The reason for calculating the voltage in the specific time period as described above is that the voltage difference is the largest when an abnormality occurs in the battery cell in the specific period. That is, it is because the abnormal precursor phenomenon of the battery cell can be most reliably detected in the specific section. On the other hand, as described above, in the present invention, the reference value for the voltage deviation (Va), the reference value for the voltage change (Vb), and/or the reference value for the voltage deviation change (Vc) may be preset, and thereto, respectively, a system warning A signal, a system critical signal and/or a system shutdown signal can be output.

In some examples, a reference value for the voltage deviation Va and an output signal therefor may be set as follows. These examples are only examples for understanding the present invention, and the present invention is not limited to the following numerical ranges.

In the set charging section shown in FIG. 5 , when the voltage deviation Va by the voltage deviation calculator 121 is about 10 mV to about 200 mV set as a reference value, and in the set discharging section shown in FIG. 5 , the voltage deviation is calculated When the voltage deviation Va by the unit 121 is approximately 50 mV to approximately 300 mV set as a reference value, the action signal output unit 130 may output a system warning signal and/or a system danger signal.

In addition, in the set charging section shown in Fig. 5, when the voltage deviation (Va) by the voltage deviation calculator 121 is approximately 200 mV set as a reference value, and in the set discharge section shown in Fig. 5, the voltage deviation (Va) When is approximately 300 mV set as a reference value, the action signal output unit 130 may output a system shutdown signal.

Here, referring back to FIGS. 2A and 2B , the voltage deviation Va may mean a difference between the maximum voltage and the minimum voltage of the battery cells S1 , S2 , S3 , and S4 .

In some examples, a reference value for the voltage change Vb and the voltage deviation change Vc and an output signal therefor may be set as follows. These examples are only examples for understanding the present invention, and the present invention is not limited to the following numerical ranges.

In the set charging period shown in FIG. 5 , the voltage calculator 120 calculates the voltage deviation change (Vc) of the individual cells of each bank after a certain time elapses (or after a certain cycle elapses) is the reference value of the voltage change (Vb) at the corresponding point in time. When it is set to approximately 30% to 100%, the action signal output unit 130 may output a system warning signal, a system danger signal, and/or a system shutdown signal.

In addition, in the set discharge period shown in FIG. 5 , the voltage calculator 120 calculates the voltage deviation change (Vc) of the individual cells of each bank after a certain time elapses (or a certain cycle elapses) at the corresponding point in time voltage change (Vb) When it is approximately 30% to 100% set as a reference value of , the action signal output unit 130 may output a system warning signal, a system danger signal, and/or a system shutdown signal.

Here, the voltage calculator 120 may obtain a predetermined time from the time estimator 150, and the number of days of use may be set between approximately 7 to 180 days, or the number of cycles may be set to approximately 20 to 200 cycles. The invention is not limited.

In addition, here, the individual cells of each bank may include S1 consisting of S11 to S14 connected in parallel in FIG. 2A, S2 consisting of S21 to S24, S3 consisting of S31 to S34, and S4 consisting of S41 to S44, voltage deviation change (Vc) may include a voltage change after a predetermined period (or a predetermined cycle) of each of the cells S1 to S4 has elapsed.

6A and 6B are graphs and tables illustrating an example of a change in voltage of a battery for explaining the operation of the abnormal state pre-detection system 100 using battery voltage data according to an embodiment of the present invention. In FIG. 6A , the X-axis is elapsed time, the Y-axis is cell voltage, and A, B, C, and D are battery cells.

As shown in FIGS. 6A and 6B , the number of cycles is 0 to 100 cycles, wherein the voltage deviation (Va), for example, the voltage change (Vb) of the battery cell D, and the voltage deviation change (Vc) of the battery cell D as an example ) was measured. As shown in FIG. 6B , the voltage change (Vb) of the battery cell D was sensed and calculated from the 50th cycle, and the voltage deviation change (Vc) of the battery cell D was also sensed and calculated.

In this example, a reference value for outputting a system warning signal, a system danger signal, and/or a system shutdown signal by the action signal output unit 130 during charging may be set as follows.

First, a reference value for the voltage deviation Va may be set to a system warning signal 20mV, a system danger signal 50mV, and a system shutdown signal 200mV. In addition, the reference value for the voltage change (Vb) may be set at 2 months and/or 50 cycles, a system warning signal 40%, a system critical signal 50%, and a system shutdown signal 70%.

Therefore, for the voltage deviation Va, the action signal output unit 130 outputs a system warning signal in 50 cycles, and does not output a system danger signal until 100 cycles. In addition, with respect to the voltage change (Vb), the action signal output unit 130 outputs a system danger signal in 50 cycles, and outputs a system shutdown signal in 100 cycles.

On the other hand, in the case of discharge, the voltage appears to be lowered, and the system warning signal, the system danger signal, and/or the system shutdown signal may be made under the above conditions.

Next, the signal output by the action signal output unit 130 due to the voltage deviation change (Vc) may be made as follows.

In the set charging section shown in Figure 5, the action signal output unit 130 is a system warning signal and / or a system danger signal when the value after a certain time elapses (or a certain cycle elapses) is greater than the reference value of about 5% to about 50% may be outputted, and a system shutdown signal may be output when it is greater than the reference value of about 30% to about 200%.

In the set discharge section shown in Figure 5, the action signal output unit 130 is a system warning signal and / or a system danger signal when the value after a certain time elapses (or a certain cycle elapses) is greater than the reference value of about 5% to about 50% may be outputted, and a system shutdown signal may be output when it is greater than the reference value of about 30% to about 200%. Here, as described above, the predetermined time may be set between about 7 to about 180 days of use (the number of cycles is about 20 to 200 cycles).

7 is a table illustrating an example of a change in voltage of a battery for explaining the operation of the abnormal state pre-detection system 100 using battery voltage data according to an embodiment of the present invention.

Here, the battery voltage deviation change Vc may be set to 20% of a system warning signal, 50% of a system danger signal, and 100% of a system shutdown signal in 50 cycles as a reference value. In this case, the action signal output unit 130 already outputs a system warning signal in 50 cycles initially set, outputs a system danger signal in 80 cycles, and outputs a system shutdown signal in 90 cycles.

What has been described above is only one embodiment for implementing the abnormal state pre-detection system using battery voltage data according to the present invention, and the present invention is not limited to the above-described embodiment, and is claimed in the claims below. As such, without departing from the gist of the present invention, it will be said that the technical spirit of the present invention exists to the extent that various modifications can be made by anyone with ordinary knowledge in the field to which the present invention belongs.

100; Anomaly pre-detection system
110; voltage sensing unit 120; voltage calculator
121; voltage deviation calculator 122; voltage change calculator
123; voltage deviation change calculator 130; Action signal output
140; SOC estimator 150; time estimator
160; reference value storage

Claims (6)

a voltage sensing unit configured to sense a voltage of each of the plurality of battery cells and provide battery voltage data for each of the plurality of battery cells;
a voltage deviation calculator for calculating a voltage deviation (Va) between each battery cell from the battery voltage data; a voltage change calculator for calculating a voltage change (Vb) of each battery cell according to time of each battery cell from the battery voltage data; A voltage for calculating a ratio of a change (Vc) of a voltage deviation of each battery cell over time and a change (Vc) of the voltage deviation with respect to a reference value of the voltage change (Vb) from the battery voltage data a voltage calculator including a deviation change calculator; and
System action by comparing the voltage deviation (Va), the voltage change (Vb), the change in voltage deviation (Vc) and the ratio of the change in voltage deviation (Vc) to the reference value of the voltage change (Vb) with a reference value An abnormal state pre-detection system using battery voltage data, including an action signal output unit for outputting a signal. The method of claim 1,
The system action signal of the action signal output unit is a system warning signal to analyze the detailed battery operation data to determine whether an actual abnormality has occurred, a system danger signal to take action on the checked abnormality, or a system to shut down the system Anomaly pre-detection system using battery voltage data, which is a shutdown signal. 3. The method of claim 2,
An abnormal state pre-detection system using battery voltage data, wherein a reference value set for outputting the system shutdown signal is higher than a reference value set for outputting the system warning signal and the system danger signal. The method of claim 1,
The voltage calculator operates in an SOC ± 10% section or a preset voltage section based on a constant voltage charging section entry time during charging of the battery cell, an abnormal state pre-detection system using battery voltage data. The method of claim 1,
The voltage calculator operates in a section of 5% to 30% of the remaining amount SOC or a section of a preset voltage when the battery cell is discharged, an abnormal state pre-detection system using battery voltage data. The method of claim 1,
The plurality of battery cells includes battery cells connected in series or battery cells connected in parallel, an abnormal state pre-detection system using battery voltage data.

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