Battery aging status detection device and method based on harmonic signal

Abstract

According to the battery aging status detection device and method based on harmonic signals in the preferred embodiments of the present invention, the battery aging status is detected by using the harmonic signal of the detection signal passing through the battery. Thus, the battery aging status can be detected in a short time during the charging and discharging cycle without being separated from the system.

Description

Technical Field

[0001] The present invention relates to a battery aging state detection device and method based on harmonic signals, and more particularly, to a battery aging state detection device and method.

[0002] In particular, the present invention relates to a device and method suitable for electric vehicles, hybrid vehicles, self-driving vehicles, etc. that use batteries as power sources, which can prevent accidents that may occur during driving due to battery discharge by monitoring the aging status of the battery in real time.

[0003] This research is related to the following projects; "Development of Next-Generation Grid Diagnostic and Monitoring Technology for Realizing Super Grid (No.2020R1A2B5B03001692)" sponsored by Yonsei University from 2020 to 2023 with funding from the Ministry of Science and ICT of Korea and support from the Korea Research Foundation, and "Korea-US Research Foundation International Industry-Academic Cooperation Research Center for New Power Technology (No.2017K1A4A3013579)" sponsored by Korea University from 2017 to 2022 with funding from the Ministry of Science and ICT of Korea and support from the Korea Research Foundation. Background Art

[0004] Predicting the life of high-capacity batteries used in electric vehicles and power grids and diagnosing aging are critical to maintaining system performance and ensuring safety. Energy storage systems (ESS) for EVs and power grids, including electric vehicles, use high-capacity batteries that combine many battery cells. In order to diagnose energy storage systems (ESS), many sensors need to continuously observe battery cells to accumulate charge / discharge data. The accumulated data can be used to diagnose the aging state of the battery through artificial intelligence models and state estimation algorithms.

[0005] Previous battery aging diagnosis technology can diagnose the aging state of the battery by discharging the remaining capacity of the battery. As an example of an accurate diagnosis method, the state of the battery can be estimated by observing the impedance change of the battery using electrochemical impedance spectroscopy (EIS). However, in previous battery aging diagnosis technology, the SOC of the battery must be discharged to 0%, which not only shortens the life of the battery, but also takes a long time to accumulate diagnostic data. In addition, although EIS can perform accurate diagnosis, there are technical problems in using expensive equipment to diagnose a device including many battery cells in real time. In recent years, there has been a demand for the expansion of the availability of high-capacity batteries and real-time diagnostic technology. Summary of the invention

[0006] The object of the present invention is to provide a battery aging state detection device and method based on harmonic signals, which detect the aging state of the battery based on the harmonic signal of the passing signal that is generated when the detection signal passes through the battery.

[0007] Other objects not explicitly stated in the present invention are further considered within the scope that can be inferred from the following detailed description and its effects.

[0008] In order to achieve the above-mentioned purpose, the present invention provides a battery aging status detection device based on harmonic signals, which is a battery aging status detection device for detecting the aging status of a battery, wherein: it comprises: a detection signal providing unit, used to apply a detection signal to the battery; a through signal acquisition unit, used to acquire a through signal that comes out of the battery after the detection signal applied to the battery by the detection signal providing unit passes through the battery; and an aging status detection unit, used to detect the aging status of the battery based on a harmonic signal of the through signal obtained by the through signal acquisition unit.

[0009] The battery is located inside the vehicle and is used as a power source for the vehicle. The battery aging status detection device is installed inside the vehicle and detects the aging status of the battery in preset time units.

[0010] Wherein, the battery aging state detection device detects the aging state of the battery during the rest period of the charging and discharging cycle of the battery.

[0011] The aging state detection unit detects the aging state of the battery based on the harmonic signal pattern of the through signal.

[0012] The aging state detection unit detects the aging state of the battery based on at least one of an odd-order harmonic signal pattern of the through signal and an even-order harmonic signal pattern of the through signal.

[0013] The aging state detection unit detects the aging state of the battery based on a harmonic signal ratio of the through signal.

[0014] The aging state detection unit detects the aging state of the battery based on at least one of an odd-order harmonic signal ratio of the through signal and an even-order harmonic signal ratio of the through signal.

[0015] The detection signal providing unit applies the detection signal formed by a sinusoidal signal to the battery.

[0016] The present invention also provides a battery aging status detection method based on harmonic signals, which is a battery aging status detection method performed in a battery aging status detection device for detecting the aging status of a battery, and includes: a step of applying a detection signal to the battery; a step of obtaining a through signal obtained by the detection signal applied to the battery passing through the battery; and a step of detecting the aging status of the battery based on a harmonic signal of the through signal.

[0017] The battery is located inside the vehicle and serves as a power source for the vehicle. The battery aging status detection device is installed inside the vehicle and executes the battery aging status detection method in preset time units to detect the aging status of the battery.

[0018] Wherein, the battery aging state detection step detects the aging state of the battery based on the harmonic signal pattern of the through signal or the harmonic signal ratio of the through signal.

[0019] In addition, the present invention provides a computer program, wherein the computer program is stored in a computer-readable recording medium, so that the above-mentioned battery aging status detection method based on harmonic signals is executed on a computer.

[0020] Effects of the Invention

[0021] According to the battery aging status detection device and method based on harmonic signals in the preferred embodiments of the present invention, the battery aging status is detected by a harmonic signal of a passing signal based on the detection signal passing through the battery. Thus, the battery aging status can be detected in a short time during the charging and discharging cycle without being separated from the system.

[0022] The effects of the present invention are not limited to the mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a block diagram for illustrating a battery aging state detection device based on harmonic signals according to a preferred embodiment of the present invention.

[0024] Figure 2 It is used to illustrate Figure 1 A block diagram of the detailed structure of the battery aging status detection device shown.

[0025] Figure 3 FIG. 1 is a diagram for explaining an example of a battery clipping circuit model according to a preferred embodiment of the present invention.

[0026] Figure 4 2 is a diagram for explaining distortion occurring on a detection signal according to a linear / nonlinear system according to a preferred embodiment of the present invention.

[0027] Figure 5 It is a diagram for explaining a design example of a battery aging state detection device according to a preferred embodiment of the present invention.

[0028] Figure 6 FIG. 2 is a diagram for explaining harmonic changes according to a battery aging state according to a preferred embodiment of the present invention.

[0029] Figure 7 It is a flow chart for illustrating a battery aging state detection method based on harmonic signals according to a preferred embodiment of the present invention.

[0030] Explanation of symbols

[0031] 100: battery aging state detection device, 110: detection signal providing unit, 130: passing signal acquiring unit, 150: aging state detection unit. DETAILED DESCRIPTION

[0032] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. Figure 1 The advantages and features of the present invention and the methods for achieving the same will become clear from the detailed embodiments described below. However, the present invention is not limited to the embodiments disclosed below, but can be embodied in various different forms. The present embodiments are provided to make the disclosure of the present invention more complete so that those skilled in the art to which the present invention belongs can fully understand the scope of the invention. The present invention is defined only by the scope of the claims. Throughout the specification, the same reference symbols refer to the same constituent elements.

[0033] In the absence of different definitions, all terms (including technical and scientific terms) used in this specification can be used as meanings that can be commonly understood by technicians in the technical field to which the present invention belongs. In addition, terms defined in commonly used dictionaries shall not be interpreted beyond or excessively unless they are clearly defined.

[0034] In this specification, the terms "first" and "second" are used to distinguish one component from other components, and the scope of rights will not be limited by these terms. For example, the first component can be named as the second component, and similarly, the second component can be named as the first component.

[0035] The identification letters (e.g., a, b, c, etc.) in the various steps of the specification are used for convenience of description and are not intended to describe the order of the various steps. The various steps may be performed in a different order than that mentioned unless specifically mentioned in the context. That is, the various steps may be performed in the same order as described, may be performed substantially simultaneously, or may be performed in a reverse order.

[0036] In this specification, expressions such as "having", "may have", "including" or "may include" refer to the existence of corresponding features (such as constituent elements such as values, functions, actions or parts), and do not exclude the existence of additional features.

[0037] In addition, in this specification, "~ part" refers to a software element or a hardware element such as an FPGA (field-programmable gate array) or an ASIC, and performs the corresponding function. However, it should be understood that "~ part" is not limited to software or hardware elements. The component "~ part" can be implemented in a storage medium that can be specified by an address. "~ part" can also be configured to regenerate one or more processors. For example, "~ part" can include various types of elements (e.g., software elements, object-oriented software elements, class elements, task elements, etc.), segments (e.g., processes, functions, attributes, programs, subroutines, program codes, etc.), drivers, firmware, microcodes, circuits, data structures, variables, etc. The functions provided by the elements and "~ parts" can be formed by combining a small number of elements and "~ parts", or can be divided into additional elements and "~ parts".

[0038] Hereinafter, preferred embodiments of a battery aging status detection device and method based on harmonic signals according to the present invention will be described in detail with reference to the accompanying drawings.

[0039] First, refer to Figures 1 to 6 A battery aging status detection device based on harmonic signals according to a preferred embodiment of the present invention is described.

[0040] Figure 1 is a block diagram for illustrating a battery aging state detection device based on harmonic signals according to a preferred embodiment of the present invention, Figure 2 It is used to illustrate Figure 1 The detailed structure of the battery aging state detection device is shown in FIG. Figure 3 is a diagram for explaining an example of a battery clipping circuit model according to a preferred embodiment of the present invention, Figure 4 is a diagram for explaining distortion occurring on a detection signal according to a linear / nonlinear system according to a preferred embodiment of the present invention, Figure 5 is a diagram for illustrating a design example of a battery aging state detection device according to a preferred embodiment of the present invention, Figure 6 FIG. 2 is a diagram for explaining harmonic changes according to a battery aging state according to a preferred embodiment of the present invention.

[0041] Reference Figure 1 According to a preferred embodiment of the present invention, a battery aging state detection device based on harmonic signals (hereinafter referred to as "battery aging state detection device") 100 detects the aging state of the battery based on the harmonic signal of the detection signal passing through the battery.

[0042] Here, the battery is located inside a vehicle (not shown) and can be used as a power source for the vehicle.

[0043] In addition, the battery aging state detection device 100 may be installed inside a vehicle to detect the aging state of the battery in preset time units.

[0044] At this time, the battery aging state detection device 100 can detect the aging state of the battery during the rest period during the charging and discharging cycle of the battery.

[0045] For this purpose, refer to Figure 2 The battery aging state detection device 100 may include a detection signal providing unit 110 , a passing signal acquiring unit 130 and an aging state detection unit 150 .

[0046] The detection signal providing part 110 may apply a detection signal to the battery.

[0047] That is, the detection signal supply unit 110 may apply a detection signal composed of a sinusoidal signal to the battery.

[0048] The through signal acquisition unit 130 may acquire a through signal which is a result of the detection signal applied to the battery by the detection signal supply unit 110 passing through the battery.

[0049] The aging state detecting unit 150 may detect the aging state of the battery based on the harmonic signal of the transmission signal acquired by the transmission signal acquiring unit 130 .

[0050] That is, the aging state detection unit 150 can detect the aging state of the battery based on the harmonic signal pattern of the passing signal. For example, the aging state detection unit 150 can detect the aging state of the battery based on at least one of the odd-order harmonic signal pattern of the passing signal and the even-order harmonic signal pattern of the passing signal.

[0051] In addition, the aging state detection unit 150 can detect the aging state of the battery based on the harmonic signal ratio of the passing signal. For example, the aging state detection unit 150 can detect the aging state of the battery based on at least one of the odd-order harmonic signal ratio of the passing signal and the even-order harmonic signal ratio of the passing signal.

[0052] In more detail, the battery aging state detection operation based on harmonic signals according to the present invention is a technology for diagnosing the aging state of the corresponding battery by analyzing the distortion of the passing signal after applying a preset signal to the battery during the charging and discharging cycle. In the present invention, the battery enters a rest period during the charging and discharging cycle in the system, at which time, a detection signal is applied to the battery while the voltage remains constant. The detection signal depends on the voltage and state of each battery. The signal passing through a normal new battery will be distorted and show a higher even harmonic ratio, while an aged battery shows a lower even harmonic ratio. Thus, the aging state can be periodically diagnosed by harmonic indicators without separating the battery from the system.

[0053] A battery is a directional energy storage device with positive and negative electrodes, such as Figure 3 As shown, it has bidirectionality. When a voltage or current signal is applied to a battery, distortion of the signal may occur due to the bidirectionality and nonlinearity of the battery.

[0054] The healthier the battery is in its normal state, the more severe the distortion of the signal passing through it will be. In particular, when a sine signal is applied, it will show clipping where both peaks are cut off. Figure 4 As shown in the figure, when the system is linear, harmonics will not occur, but when the system is nonlinear, harmonics will occur. When the signal passes through a nonlinear system, the distortion of the signal is also divided into symmetric and asymmetrical conditions. Both distorted signals show that the peak points of the signal are truncated. In the case of symmetric signals, odd-order harmonic patterns mainly appear, and in the case of asymmetric signals, patterns including even harmonics appear.

[0055] For example, Figure 5 As shown, a sinusoidal voltage / current signal is used as a detection signal, a detection signal is applied to the battery using a DAQ device, and the through signal is analyzed in Labview to monitor the harmonic pattern.

[0056] If the battery aging state detection operation based on harmonic signals according to the present invention is used, the battery aging index can be measured within 0.02 seconds to 1 second during the charging and discharging cycle without being separated from the system. Figure 6 As shown, the signal passing through a normal battery is asymmetrical and includes both odd harmonic components and even harmonic components, but the distortion of the signal passing through an aged battery is symmetrical and mainly shows odd harmonic components. Compared with the prior art, full discharge is not required, and the cost required to design a system for applying a signal is more economical than EIS, and the diagnosis time is also shorter, so it is easy to apply it to algorithms and diagnostic techniques for diagnosing multiple battery cells.

[0057] Next, we will refer to Figure 7 A battery aging status detection method based on harmonic signals according to a preferred embodiment of the present invention is described.

[0058] Figure 7 is a flow chart showing a battery aging state detection method based on harmonic signals according to a preferred embodiment of the present invention.

[0059] Reference Figure 7 , the battery aging state detection device 100 applies a detection signal to the battery (S110).

[0060] That is, the battery aging state detection device 100 may apply a detection signal formed of a sinusoidal signal to the battery.

[0061] Then, the battery aging state detection apparatus 100 acquires a passing signal obtained by the detection signal applied to the battery passing through the battery ( S120 ).

[0062] Then, the battery aging state detection apparatus 100 detects the aging state of the battery based on the harmonic signal of the pass signal ( S130 ).

[0063] That is, the battery aging state detection device 100 can detect the aging state of the battery based on the harmonic signal pattern of the passing signal. For example, the battery aging state detection device 100 can detect the aging state of the battery based on at least one of the odd-order harmonic signal pattern of the passing signal and the even-order harmonic signal pattern of the passing signal.

[0064] In addition, the battery aging state detection device 100 can detect the aging state of the battery based on the harmonic signal ratio of the passing signal. For example, the battery aging state detection device 100 can detect the aging state of the battery based on at least one of the odd-order harmonic signal ratio of the passing signal and the even-order harmonic signal ratio of the passing signal.

[0065] Above, although it is explained that all the constituent elements forming the embodiments of the present invention are combined into one or combined with each other to work, the present invention is not limited to these embodiments. That is, as long as it is within the scope of the purpose of the present invention, all its constituent elements can also be selectively combined with at least one to work. In addition, although all the constituent elements can be implemented by an independent hardware, it is also possible to selectively combine a part or all of the constituent elements to be implemented by a computer program having a program module that performs a part or all of the functions of the combination in one or more hardware. In addition, the computer program as described above is stored in a computer readable medium (Computer Readable Media) such as a USB memory, a CD disk, a flash memory, etc., and is read and executed by a computer, thereby, an embodiment of the present invention can be implemented. The recording medium of the computer program may include a magnetic recording medium, an optical recording medium, etc.

[0066] The above description is merely an illustrative description of the technical idea of ​​the present invention. As long as one is a person of ordinary skill in the technical field to which the present invention belongs, various modifications, deformations and substitutions can be made without departing from the essential characteristics of the present invention. Therefore, the embodiments and drawings disclosed in the present invention are not used to limit the technical idea of ​​the present invention, but to illustrate the present invention, and the scope of the technical idea of ​​the present invention is not limited to such embodiments. The protection scope of the present invention should be interpreted according to the claims, and should be interpreted as all technical ideas within the same scope as the claims are included in the scope of rights of the present invention.

Claims

1. A battery aging state detection device based on harmonic signals, which is a battery aging state detection device for detecting the aging state of a battery, wherein: include: A detection signal providing unit, used for applying a detection signal to the battery; a through signal acquisition unit for acquiring a through signal which is a result of the detection signal applied to the battery by the detection signal providing unit passing through the battery; as well as an aging state detecting unit for detecting the aging state of the battery based on at least one of an odd-order harmonic signal pattern and ratio of the through signal and an even-order harmonic signal pattern and ratio of the through signal obtained by the through signal acquiring unit, The aging state of the battery is detected during a rest period in a charge and discharge cycle of the battery, during which the voltage is kept constant.

2. The battery aging status detection device based on harmonic signals according to claim 1, wherein: The battery is located inside the vehicle and serves as a power source for the vehicle. The battery aging state detection device is installed inside the vehicle and detects the aging state of the battery in preset time units.

3. The battery aging status detection device based on harmonic signals according to claim 2, wherein: The detection signal supply section applies the detection signal formed of a sinusoidal signal to the battery.

4. A battery aging state detection method based on harmonic signals, which is a battery aging state detection method performed in a battery aging state detection device for detecting the aging state of a battery, wherein: include: The step of applying a detection signal to the battery; The step of acquiring a passing signal which is generated when the detection signal applied to the battery passes through the battery; as well as a step of detecting the aging state of the battery based on at least one of an odd-order harmonic signal pattern and ratio of the through signal and an even-order harmonic signal pattern and ratio of the through signal, The aging state of the battery is detected during a rest period in the charge and discharge cycle of the battery, during which the voltage is kept constant.

5. The battery aging status detection method based on harmonic signals according to claim 4, wherein: The battery is located inside the vehicle and serves as a power source for the vehicle. The battery aging state detection device is installed inside the vehicle and executes the battery aging state detection method in preset time units to detect the aging state of the battery.

6. A computer program, wherein: The computer program is stored in a computer-readable recording medium, so that the battery aging state detection method based on harmonic signals as claimed in claim 4 is executed on a computer.

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