Graphene heating device and automobile seat

Abstract

The invention relates to the technical field of automobile seats, in particular to a graphene heating device and an automobile seat, and the graphene heating device comprises a graphene heating film, a positive electrode plate, a negative electrode plate, a redundancy protection wire and an open circuit control assembly; the positive electrode plate is electrically connected with a positive electrode of an external power supply, and the negative electrode plate is electrically connected with a negative electrode of the external power supply to form a power supply loop; the length of the redundant protection wire is larger than that of the positive electrode plate or the negative electrode plate, the two ends of the redundant protection wire are electrically connected with the two ends of the positive electrode plate respectively, and / or the two ends of the redundant protection wire are electrically connected with the two ends of the negative electrode plate respectively; and the circuit break control assembly is connected in series to the power supply loop and is used for disconnecting the power supply loop when abnormal fluctuation of the current is detected. Dual protection is formed by the redundant protection wires and the circuit break control assembly, and abnormal heating, heating function failure or ablation at the damaged or broken positions of the electrode plates are prevented.

Description

Technical Field

[0001] The invention relates to the technical field of automobile seats, and in particular to a graphene heating device and an automobile seat. Background Art

[0002] The seat heating function can improve the comfort of vehicle riding and is gradually becoming popular with the development of technology in the field of vehicle transportation. Traditional car seats used in the market mostly use the heating method of built-in resistance wire. This heating method has the problem of uneven heating area, and the comfort felt by the human body is poor. In addition, the resistance wire has a large resistance value, slow heating, high energy consumption, and easy breakage. There are disadvantages such as heating function failure and easy surface ablation, and the safety factor is low. The existing graphene heating technology solves the above problems. It usually adheres two electrode sheets to the opposite sides of the graphene membrane through conductive slurry. The wiring terminals of the two electrode sheets are connected to an external power supply to form a uniform electric field between the two electrode sheets, so that the graphene membrane heats up evenly and quickly, meeting the comfort requirements of car seats.

[0003] However, the electrode sheets of this electrode sheet group have relatively poor deformation ability, especially when the electrode sheets are longitudinally arranged on a soft seat and are repeatedly sat on and pressed, the electrode sheets will be damaged in the middle position of the seat or even directly break into two sections, causing abnormal heating, electrical function failure and even sparking and burning at the break. After the electrode sheet is completely broken, the section of the electrode sheet far away from the terminal will also cause unstable voltage due to poor contact, affecting the heating effect of the seat. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a graphene heating device and a car seat, which solve the technical problem that the existing graphene heating device generates abnormal heat, fails in electrical function or even ignites and burns after the electrode sheet is damaged or broken, thereby affecting the heating effect of the seat.

[0006] (II) Technical solution

[0007] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0008] In a first aspect, an embodiment of the present invention provides a graphene heating device, comprising: a graphene heating film, a positive electrode sheet, a negative electrode sheet, a redundant protection wire and a circuit breaker control component;

[0009] The positive electrode sheet and the negative electrode sheet are electrically connected to two opposite edges of the graphene heating film, respectively, and the positive electrode sheet is electrically connected to the positive electrode of an external power source, and the negative electrode sheet is electrically connected to the negative electrode of the external power source to form a power supply circuit;

[0010] The length of the redundant protection wire is greater than the length of the positive electrode sheet or the negative electrode sheet, and the two ends of the redundant protection wire are electrically connected to the two ends of the positive electrode sheet, and / or the two ends of the redundant protection wire are electrically connected to the two ends of the negative electrode sheet;

[0011] The circuit breaker control component is connected in series to the power supply circuit, and is used to disconnect the power supply circuit when abnormal current fluctuation is detected.

[0012] Optionally, the redundant protection conductor is a curved strip-shaped thin sheet, and an insulating layer is provided on the outer side of the strip-shaped thin sheet.

[0013] Optionally, the redundant protection wire is a metal wire, and an insulating layer is provided on the outer side of the wire.

[0014] Optionally, a seamless gasket is provided on a side of the positive electrode sheet or the negative electrode sheet facing away from the graphene heating film, and the metal wire is bent and arranged in the seamless gasket.

[0015] Optionally, the circuit breaker control assembly includes: a current detection circuit, a controller and an electric control switch;

[0016] The current detection circuit is connected in series in the power supply circuit and is used to detect the real-time current value of the power supply circuit;

[0017] The controller is connected to the current control circuit for monitoring the real-time current value and sending a power-off instruction to the electric control switch when the real-time current value fluctuates abnormally.

[0018] The electric control switch is connected in series in the power supply circuit and is in communication connection with the controller, and is used for disconnecting the power supply circuit when receiving the power-off instruction.

[0019] Optionally, the controller comprises:

[0020] A sampling module, based on a preset sampling frequency, obtains a current value sequence of the power supply circuit through the current detection circuit; and based on a preset window width, slides on the current value sequence to obtain a real-time target sequence;

[0021] A wavelet decomposition module performs wavelet decomposition on the real-time target sequence based on a wavelet basis function to obtain approximate wavelet coefficients and detail wavelet coefficients at N scales to form a wavelet coefficient sequence; N is a positive integer greater than or equal to 2;

[0022] The judgment module is used to match and query the wavelet coefficient sequence of the real-time target sequence with the abnormal feature sequence in the preset abnormal feature library. If a matching abnormal feature sequence is found, it is determined that the current real-time target sequence has abnormal current fluctuations and a power-off instruction is generated.

[0023] Optionally, in the wavelet decomposition module, performing wavelet decomposition on the real-time target sequence based on the wavelet basis function includes: performing wavelet decomposition using a corresponding preset wavelet basis function according to the heating stage of the current real-time target sequence;

[0024] The judging module comprises:

[0025] A preliminary selection unit, used to determine the heating stage of the current real-time target sequence, and according to the heating stage of the current real-time target sequence, query the abnormal feature sequence with the same heating stage in the abnormal feature library as the preliminary selection sequence;

[0026] A candidate unit is used to traverse the preliminary selection sequence, calculate the Euclidean distance between the current wavelet coefficient sequence and each preliminary selection sequence, and take the preliminary selection sequence whose Euclidean distance is less than a first preset value as a candidate sequence;

[0027] A wavelet entropy unit, used to calculate the current wavelet entropy vector of the current real-time target sequence;

[0028] A generating unit, used for calculating the similarity between the current wavelet entropy vector and the historical wavelet entropy vector contained in the candidate sequence, and when the similarity between the historical wavelet entropy vector of any candidate sequence and the current wavelet entropy vector is greater than a second preset value, it is determined that the current real-time target sequence has abnormal current fluctuations, and a power-off instruction is generated;

[0029] Among them, the abnormal feature library includes multiple abnormal feature sequences, each abnormal feature sequence includes: a historical current value sequence formed by a damaged or broken electrode sheet in a certain heating stage, based on the preset wavelet basis function corresponding to the heating stage, the historical current value sequence is subjected to wavelet decomposition to obtain historical approximate wavelet coefficients, historical detail wavelet coefficients and historical wavelet entropy vectors; and the heating stage corresponding to the historical current value sequence.

[0030] Optionally, the temperature rise stage includes a cold start period, a temperature rise period and a stabilization period arranged in chronological order from the start of the graphene heating device;

[0031] The wavelet decomposition is performed using a preset wavelet basis function according to the temperature rise stage of the current current value sequence, including:

[0032] In the startup phase, Haar wavelet is used as the wavelet basis function;

[0033] During the warming period, Coiflet wavelet was used as the wavelet basis function;

[0034] In the stable period, Biorthogonal wavelet is used as the wavelet basis function.

[0035] Optionally, in the wavelet entropy unit, calculating the current wavelet entropy vector of the current real-time target sequence includes:

[0036] Extract the detail wavelet coefficient sequence W from the wavelet coefficient sequence x (j,k), j is a positive integer less than or equal to N, and k represents the position number of the detail wavelet coefficient at the jth scale;

[0037] For the detail wavelet coefficients at each scale, based on formula (1), the relative distribution probability of each detail wavelet coefficient is determined to obtain the probability distribution function of the detail wavelet coefficients at this scale;

[0038]

[0039] p j,k Represents the distribution probability of the kth detail wavelet coefficient at the jth scale;

[0040] Based on the probability distribution function of the detail wavelet coefficients at each scale, the wavelet entropy H at each scale is calculated according to formula (2): j , get the current wavelet entropy vector [H 1 ,H 2 ,…,H j ,…,H N ];

[0041] H j =-∑ k p j,k logp j,k (2);

[0042] H j represents the wavelet entropy at the jth scale.

[0043] In a second aspect, an embodiment of the present invention provides a car seat, comprising the graphene heating device described in the first aspect.

[0044] (III) Beneficial effects

[0045] The graphene heating device proposed in the present invention includes: a graphene heating film, a positive electrode sheet, a negative electrode sheet, a redundant protection wire and a circuit breaking control component; the positive electrode sheet and the negative electrode sheet are electrically connected to two opposite edges of the graphene heating film, respectively, and the positive electrode sheet is electrically connected to the positive pole of an external power supply, and the negative electrode sheet is electrically connected to the negative pole of the external power supply to form a power supply circuit; the two ends of the redundant protection wire are electrically connected to the two ends of the positive electrode sheet, respectively, and / or the two ends of the redundant protection wire are electrically connected to the two ends of the negative electrode sheet, respectively; the circuit breaking control component is connected in series to the power supply circuit, and is used to disconnect the power supply circuit when an abnormal current fluctuation is detected.

[0046] The redundant protection wire and the circuit breaker control assembly form a double protection. When the positive electrode sheet and the negative electrode sheet are intact, the redundant protection wire will not affect the positive electrode sheet or the negative electrode sheet; when the positive electrode sheet or the negative electrode sheet is damaged or broken in the middle, the redundant protection wire can be used as a wire to maintain the electrical connection between the two ends of the electrode sheet, so that the voltage value on the electrode sheet broken into two sections remains the same, thereby preventing abnormal heating at the damaged or broken part from causing sparks and ablation. Moreover, the section of the broken electrode sheet away from the wiring terminal can still be connected to the power supply circuit to obtain an equal voltage to meet the current carrying requirements due to the redundant protection wire, thereby ensuring the overall heating effect of the graphene heating device. Furthermore, when the redundant protection wire also fails due to special reasons, the circuit breaker control assembly can disconnect the power supply circuit between the electrode sheet and the power supply when abnormal current fluctuations are detected, thereby preventing abnormal heating at the damaged or broken part from causing sparks and ablation. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A schematic diagram of the structure of a graphene heating device provided in an embodiment;

[0048] Figure 2 A schematic diagram of the architecture of a controller provided in an embodiment. DETAILED DESCRIPTION

[0049] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0050] Embodiment 1

[0051] like Figure 1 As shown, this embodiment provides a graphene heating device, including: a graphene heating film 1, a positive electrode sheet 2, a negative electrode sheet 3, a redundant protection wire 4 and a circuit breaker control component 5.

[0052] The positive electrode sheet 2 and the negative electrode sheet 3 are electrically connected to two opposite edges of the graphene heating film 1 respectively, and the positive electrode sheet 2 is electrically connected to the positive pole of the external power supply 6, and the negative electrode sheet 3 is electrically connected to the negative pole of the external power supply 6 to form a power supply circuit.

[0053] The length of the redundant protection wire 4 is greater than the length of the positive electrode sheet 2 or the negative electrode sheet 3, and the two ends of the redundant protection wire 4 are electrically connected to the two ends of the positive electrode sheet 2, and / or the two ends of the redundant protection wire 4 are electrically connected to the two ends of the negative electrode sheet 3.

[0054] The circuit breaker control component 5 is connected in series to the power supply circuit, and is used to disconnect the power supply circuit when abnormal current fluctuation is detected.

[0055] The redundant protection wire 4 and the circuit breaker control component 5 form a double protection. When the positive electrode sheet 2 and the negative electrode sheet 3 are intact, the redundant protection wire 4 will not affect the positive electrode sheet 2 or the negative electrode sheet 3; when the positive electrode sheet 2 or the negative electrode sheet 3 is damaged or broken from the middle, the redundant protection wire 4 can be used as a wire to maintain the electrical connection between the two ends of the electrode sheet, so that the voltage value on the electrode sheet broken into two sections is still the same, thereby preventing abnormal heating and ablation at the damaged or broken part. Moreover, the second section 202 of the broken electrode sheet away from the terminal can still be connected to the power supply circuit to obtain an equal voltage to meet the current carrying requirements because of the redundant protection wire 4, thereby ensuring the overall heating effect of the graphene heating device. Further, when the redundant protection wire 4 also fails due to special reasons, the circuit breaker control component 5 can disconnect the power supply circuit between the electrode sheet and the power supply 6 when detecting abnormal current fluctuations caused by damage or breakage of the electrode sheet, thereby preventing abnormal heating and ablation at the damaged or broken part.

[0056] In actual application scenarios, the two ends of the redundant protection wire 4 can be respectively arranged on both sides of any easily broken position of the positive electrode sheet 2 or the negative electrode sheet 3, and the half-section of the electrode sheet that cannot obtain a stable voltage supply after breaking can be electrically connected to the terminal or the power supply wire. It should be noted that the resistance of both the electrode sheet itself and the redundant protection wire 4 itself is low enough to be ignored, so after the electrode sheet breaks, when the second section 202 of the electrode sheet away from the terminal is connected to the terminal through the redundant protection wire 4, the voltage obtained is the same as the voltage obtained by the first section 201 of the electrode sheet close to the terminal.

[0057] In a specific implementation of this embodiment, in order to facilitate mass production on an assembly line, the redundant protection wire may be a curved strip-shaped thin sheet or a metal wire.

[0058] Specifically, the redundant protection conductor is a curved thin strip, and an insulating layer is provided on the outside of the thin strip. The thin strip has the ability to deform to prevent it from breaking when subjected to external force. Preferably, the thin strip is Figure 1 The C-shaped sheet shown, or a continuous S-shaped sheet or a continuous V-shaped sheet. The redundant protection wire is arranged as a strip sheet with a fixed shape, which is more convenient for placement and assembly. Moreover, the continuous S-shaped or continuous V-shaped strip sheet is arranged on the seat cushion of the car seat, and can have a certain longitudinal deformation ability after being pressed. The C-shaped strip sheet can bypass the main deformation area of ​​the seat cushion to a certain extent, thereby reducing the probability of fracture, so that it can still play an effective role after the electrode sheet is fractured.

[0059] Specifically, the redundant protection wire is a metal wire, and an insulating layer is provided on the outside of the wire. The length of the metal wire is greater than the distance between the wiring terminal and the non-wiring terminal of the electrode sheet, and the metal wire is coated with an insulating layer. More preferably, a traceless gasket is provided on the side of the positive electrode sheet or the negative electrode sheet facing away from the graphene heating film, and the metal wire is bent and arranged in the traceless gasket to have a deformation redundancy when subjected to external force to prevent breakage. The traceless gasket can reduce the foreign body sensation of the metal wire and make the car seat more comfortable.

[0060] Preferably, in order to balance the cost and redundant deformation capacity of the metal wire, the ratio of the distance from the connection terminal to the non-connection terminal of the electrode sheet to the length of the metal wire is [0.67, 0.83], that is, the length of the metal wire is 20% to 50% more than the distance from the connection terminal to the non-connection terminal of the electrode sheet, so as to adapt to the deformation caused by the seat while better controlling the production cost.

[0061] In addition, this embodiment also provides a car seat, including the above-mentioned graphene heating device.

[0062] Embodiment 2

[0063] This embodiment specifically describes the structure of the circuit breaker control component.

[0064] like Figure 1 As shown, this embodiment provides a graphene heating device, including: a graphene heating film 1, a positive electrode sheet 2, a negative electrode sheet 3, a redundant protection wire 4 and a circuit breaker control component 5.

[0065] The positive electrode sheet 2 and the negative electrode sheet 3 are electrically connected to two opposite edges of the graphene heating film 1 respectively, and the positive electrode sheet 2 is electrically connected to the positive pole of the external power supply 6, and the negative electrode sheet 3 is electrically connected to the negative pole of the external power supply 6 to form a power supply circuit.

[0066] The length of the redundant protection wire 4 is greater than the length of the positive electrode sheet 2 or the negative electrode sheet 3, and the two ends of the redundant protection wire 4 are electrically connected to the two ends of the positive electrode sheet 2, and / or the two ends of the redundant protection wire 4 are electrically connected to the two ends of the negative electrode sheet 3.

[0067] The circuit breaker control component 5 is connected in series to the power supply circuit, and is used to disconnect the power supply circuit when abnormal current fluctuation is detected.

[0068] Specifically, the circuit breaker control component 5 includes: a current detection circuit 501 , a controller 502 and an electric control switch 503 .

[0069] The current detection circuit 501 is connected in series in the power supply circuit and is used to detect the real-time current value of the power supply circuit.

[0070] The controller 502 is in communication with the current control circuit 501 and is used to monitor the real-time current value and send a power-off instruction to the electronically controlled switch when the real-time current value fluctuates abnormally.

[0071] The electric control switch 503 is connected in series in the power supply circuit and is in communication with the controller 502, and is used to disconnect the power supply circuit when receiving the power-off instruction.

[0072] In actual applications, damage or breakage of the electrode sheet will cause the circuit in the power supply circuit to produce abnormal fluctuations without obvious patterns. When the fluctuation range of the current is detected to be greater than the preset threshold, such as ±15%, it can be determined that the electrode sheet is damaged or broken. However, a variety of electrical devices are usually integrated in the car cabin, so there may be environmental interference or electromagnetic interference to the current detection circuit. Mobile phones, tablets and other electronic devices used by users in the car cabin sometimes interfere with the current detection circuit. This interference usually has no certain pattern to follow and cannot be simply filtered out using a bandpass filter.

[0073] In view of the above problems, in a preferred implementation of this embodiment, as Figure 2 As shown, the controller includes: a sampling module, a wavelet decomposition module and a judgment module.

[0074] The sampling module obtains the current value sequence of the power supply circuit through the current detection circuit based on a preset sampling frequency, and obtains the real-time target sequence by sliding on the current value sequence based on a preset window width. Preferably, the sampling frequency is [200HZ, 2000HZ].

[0075] The wavelet decomposition module performs wavelet decomposition on the real-time target sequence based on the wavelet basis function to obtain approximate wavelet coefficients and detail wavelet coefficients at N scales to form a wavelet coefficient sequence; N is a positive integer greater than or equal to 2. Preferably, the value range of N is [4,8].

[0076] The judgment module is used to match and query the wavelet coefficient sequence of the real-time target sequence with the abnormal feature sequence in the preset abnormal feature library. If a matching abnormal feature sequence is found, it is determined that the current real-time target sequence has abnormal current fluctuations and a power-off instruction is generated.

[0077] Wavelet decomposition is a multi-resolution analysis process. Its core idea is to decompose the signal at different scales and gradually separate the low-frequency and high-frequency components of the signal. In each level of decomposition, the original signal or the approximate signal obtained by the previous level of decomposition will pass through a pair of complementary filters: low-pass filter and high-pass filter. The low-pass filter is used to extract the low-frequency part of the signal, and the high-pass filter is used to extract the high-frequency part of the signal.

[0078] The real-time target sequence is defined as x[n], n=0,1,2,…,R-1. In the wavelet decomposition at the jth scale, the low-pass filter coefficient used is h[k], and the high-pass filter coefficient is g[k], k=0,1,…,L-1 (L is the filter length).

[0079] The approximate wavelet coefficients are obtained by downsampling the signal after passing through a low-pass filter. The j+1 level approximate wavelet coefficients c j+1 The calculation formula for [m] is:

[0080] c j+1 [m] = ∑ n h[n-2m]c j [n] (3);

[0081] where c j [n] is the approximate wavelet coefficient at the jth scale. When j = 0, c 0 [n] = x[n]. Downsampling means retaining only the signal values ​​at even positions, which reduces the length of the signal by half. The approximate wavelet coefficients represent the low-frequency information of the signal at the current scale and reflect the overall trend and profile of the current signal. As the decomposition level increases, the length of the approximate wavelet coefficients gradually decreases, but the frequency range of the signal it represents also becomes lower and lower.

[0082] The detail wavelet coefficient is obtained by downsampling the signal after passing through a high-pass filter. The j+1th level detail wavelet coefficient d j+1 The calculation formula for [m] is:

[0083] d j+1 [m] = ∑ n g[n-2m]c j [n] (4);

[0084] The detail wavelet coefficients represent the high-frequency information of the signal at the current scale, reflecting the local changes and detail characteristics of the signal. For example, information such as mutations, noise, and rapid changes in the signal is mainly contained in the detail wavelet coefficients. Similarly, as the decomposition level increases, the length of the detail wavelet coefficients gradually decreases, but the signal frequency range they represent will gradually focus on higher frequency bands.

[0085] Based on the above-mentioned wavelet decomposition module, the controller provided in this embodiment can decompose the current signal into approximate signals and detail signals at different scales to achieve multi-resolution analysis. By analyzing the signals at different scales, the characteristics of the current signal can be observed from multiple levels, both macroscopic and microscopic. In the process of detecting the gradual breakage of the electrode sheet, the low-frequency approximate signal may show a slow change in the overall trend of the current, while the high-frequency detail signal can capture the high-frequency noise and mutations generated at the moment of breakage, thereby grasping the abnormal characteristics more comprehensively. Moreover, the coefficients corresponding to the higher-frequency stages corresponding to the interference or noise can be ignored, thereby effectively distinguishing between faults and noise, reducing the impact of noise, and improving the accuracy and reliability of the characteristics, thereby avoiding misjudgment caused by environmental noise or electromagnetic interference.

[0086] More preferably, in the wavelet decomposition module, performing wavelet decomposition on the real-time target sequence based on the wavelet basis function includes: performing wavelet decomposition using a corresponding preset wavelet basis function according to the heating stage of the current real-time target sequence.

[0087] Specifically, the heating stage includes a cold start period, a heating period and a stabilization period arranged in chronological order from the start of the graphene heating device;

[0088] The wavelet decomposition is performed using a preset wavelet basis function according to the temperature rise stage of the current current value sequence, including:

[0089] During the cold start period, for example, from 0 to 30 seconds after the graphene heating device is started, Haar wavelet is used as the wavelet basis function. The current signal changes relatively drastically during the cold start period, and there may be some sudden rising edges. Haar wavelet has tight support, can quickly capture the mutation of the signal, and is simple to calculate. It is more suitable for the cold start period, which requires rapid detection of the start and initial changes of the signal. It can preliminarily extract the general outline and main changes of the signal in a short time, providing a basis for further analysis.

[0090] During the heating period, for example, from the 31st second to the 180th second after the graphene heating device is started, Coiflet wavelet is used as the wavelet basis function. Coiflet wavelet has a higher vanishing moment and better frequency characteristics. During the heating period, it can effectively separate the low-frequency trend components and high-frequency detail components in the signal. For some periodic or non-periodic current fluctuations that may exist during the seat heating process, it can accurately capture their frequency characteristics and changing laws, which is helpful to discover abnormal current fluctuation patterns. Moreover, its higher vanishing moment can make the decomposed coefficients more sparse, which is more conducive to highlighting the main features of the signal.

[0091] During the stable period (for example, 180 seconds and beyond after the graphene heating device is started), the Biorthogonal wavelet is used as the wavelet basis function. The current signal during the stable period is relatively stable, with mainly some small fluctuations around a stable value. The Biorthogonal wavelet has biorthogonality and can better restore the characteristics of the original signal when reconstructing the signal. It is very helpful for situations such as the stable period where accurate restoration of signal details is required. It can analyze the small fluctuations in the current signal during the stable period while minimizing distortion, detect possible abnormal small changes, and its calculation is relatively simple, which is suitable for processing long-term stable signals.

[0092] Based on the wavelet basis functions corresponding to the above-mentioned heating stages, the abnormal feature library includes multiple abnormal feature sequences, each abnormal feature sequence includes: a historical current value sequence formed by a damaged or broken electrode sheet in a certain heating stage, based on the preset wavelet basis function corresponding to the heating stage, the historical current value sequence is subjected to wavelet decomposition to obtain historical approximate wavelet coefficients, historical detail wavelet coefficients and historical wavelet entropy vectors; and the heating stage corresponding to the historical current value sequence.

[0093] Based on the above-mentioned current value change characteristics in different heating stages, this embodiment respectively sets up wavelet basis functions adapted thereto to perform wavelet decomposition, so as to more finely obtain the change characteristics of the current current value sequence, and combine with the abnormal feature library to improve the accuracy of the controller's judgment on abnormal current fluctuations.

[0094] Corresponding to the above wavelet decomposition module and abnormal feature library, such as Figure 2 As shown, the judgment module includes: a preliminary selection unit, a candidate unit, a wavelet entropy unit, and a generation unit.

[0095] The preliminary selection unit is used to determine the heating stage of the current real-time target sequence, and according to the heating stage of the current real-time target sequence, search the abnormal feature library for an abnormal feature sequence with the same heating stage as the preliminary selection sequence.

[0096] The candidate unit is used to traverse the preliminary selection sequence, calculate the Euclidean distance between the current wavelet coefficient sequence and each preliminary selection sequence, and take the preliminary selection sequence whose Euclidean distance is less than a first preset value as a candidate sequence.

[0097] The wavelet entropy unit is used to calculate the second current wavelet entropy vector of the current real-time target sequence.

[0098] The generation unit is used to calculate the similarity between the current wavelet entropy vector and the historical wavelet entropy vector contained in the candidate sequence. When the similarity between the historical wavelet entropy vector of any candidate sequence and the current wavelet entropy vector is greater than a preset value, it is determined that the current real-time target sequence has abnormal current fluctuations and a power-off instruction is generated.

[0099] Specifically, in the wavelet entropy unit, the current wavelet entropy vector of the current real-time target sequence is calculated, including:

[0100] Extract the detail wavelet coefficient sequence W from the wavelet coefficient sequence x (j, k), j is a positive integer less than or equal to N, k represents the position number of the detail wavelet coefficient at the jth scale; W x The subscript x in (j,k) represents the real-time target sequence x[n].

[0101] For the detail wavelet coefficients at each scale, based on formula (1), the relative distribution probability of each detail wavelet coefficient is determined to obtain the probability distribution function of the detail wavelet coefficients at this scale;

[0102]

[0103] p j,k Represents the distribution probability of the kth detail wavelet coefficient at the jth scale;

[0104] Based on the probability distribution function of the detail wavelet coefficients at each scale, the wavelet entropy H at each scale is calculated according to formula (2): j , get the current wavelet entropy vector [H 1 ,H 2 ,…,H j ,…,H N ];

[0105] H j =-∑ k p j,k logp j,k (2);

[0106] H j represents the wavelet entropy at the jth scale.

[0107] Information entropy is a measure of uncertainty. In wavelet entropy, the uncertainty of the signal at the corresponding scale is quantified by calculating the information entropy of the wavelet coefficients. The higher the complexity of the signal, the more dispersed the distribution of its wavelet coefficients, and the larger the corresponding wavelet entropy value. In the above calculation unit, different degrees of fracture may cause changes in the energy distribution and complexity of the current signal at different scales. By calculating the wavelet entropy, these changing characteristics can be captured. For example, when the electrode sheet is slightly fractured, the wavelet entropy value at some smaller scales may increase, which means that the detailed information of the signal at these scales becomes more complex; and when the degree of fracture increases, the wavelet entropy value at multiple scales may change significantly. By comparing the wavelet entropy features in the current value sequence and the abnormal feature sequence pre-saved in the abnormal feature library, the corresponding relationship between the wavelet entropy feature and the degree of fracture of the electrode sheet can be established, thereby realizing the accurate identification and evaluation of the abnormal current caused by damage or fracture of the electrode sheet.

[0108] The present invention is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present invention. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions.

[0109] It should be noted that in the claims, any reference numerals placed between brackets shall not be construed as limiting the claims. The word "comprising" does not exclude the presence of components or steps not listed in the claims. The word "a" or "an" preceding a component does not exclude the presence of a plurality of such components. The invention may be implemented by means of hardware comprising several different components and by means of a suitably programmed computer. In the claims enumerating several means, several of these means may be embodied by the same hardware. The use of the words first, second, third, etc., is for convenience of expression only and does not indicate any order. These words may be understood as part of the component name.

[0110] In addition, it should be noted that, in the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0111] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments after knowing the basic creative concept. Therefore, the claims should be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0112] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention should also include these modifications and variations.

Claims

1. A graphene heating device, characterized in that: include: Graphene heating film, positive electrode sheet, negative electrode sheet, redundant protection wire and circuit breaker control assembly; The positive electrode sheet and the negative electrode sheet are electrically connected to two opposite edges of the graphene heating film, respectively, and the positive electrode sheet is electrically connected to the positive electrode of an external power source, and the negative electrode sheet is electrically connected to the negative electrode of the external power source to form a power supply circuit; The length of the redundant protection wire is greater than the length of the positive electrode sheet or the negative electrode sheet, and the two ends of the redundant protection wire are electrically connected to the two ends of the positive electrode sheet, and / or the two ends of the redundant protection wire are electrically connected to the two ends of the negative electrode sheet; The circuit breaker control component is connected in series to the power supply circuit, and is used to disconnect the power supply circuit when abnormal current fluctuation is detected.

2. The graphene heating device according to claim 1, characterized in that: The redundant protection conductor is a curved strip-shaped thin sheet, and an insulating layer is arranged on the outer side of the strip-shaped thin sheet.

3. The graphene heating component according to claim 1, characterized in that: The redundant protection wire is a metal wire, and an insulating layer is arranged on the outer side of the wire.

4. The graphene heating component according to claim 3, characterized in that: A traceless gasket is provided on a side of the positive electrode sheet or the negative electrode sheet facing away from the graphene heating film, and the metal wire is arranged in a curved manner inside the traceless gasket.

5. The graphene heating device according to claim 1, characterized in that: The circuit breaker control assembly includes: a current detection circuit, a controller and an electric control switch; The current detection circuit is connected in series in the power supply circuit and is used to detect the real-time current value of the power supply circuit; The controller is connected to the current control circuit for monitoring the real-time current value and sending a power-off instruction to the electric control switch when the real-time current value fluctuates abnormally. The electric control switch is connected in series in the power supply circuit and is in communication connection with the controller, and is used for disconnecting the power supply circuit when receiving the power-off instruction.

6. The graphene heating device according to claim 5, characterized in that: The controller comprises: A sampling module, based on a preset sampling frequency, obtains a current value sequence of the power supply circuit through the current detection circuit; and based on a preset window width, slides on the current value sequence to obtain a real-time target sequence; A wavelet decomposition module performs wavelet decomposition on the real-time target sequence based on a wavelet basis function to obtain approximate wavelet coefficients and detail wavelet coefficients at N scales to form a wavelet coefficient sequence; N is a positive integer greater than or equal to 2; The judgment module is used to match and query the wavelet coefficient sequence of the real-time target sequence with the abnormal feature sequence in the preset abnormal feature library. If a matching abnormal feature sequence is found, it is determined that the current real-time target sequence has abnormal current fluctuations and a power-off instruction is generated.

7. The graphene heating device according to claim 6, characterized in that: In the wavelet decomposition module, the wavelet decomposition of the real-time target sequence based on the wavelet basis function includes: performing wavelet decomposition using a corresponding preset wavelet basis function according to the heating stage of the current real-time target sequence; The judging module comprises: A preliminary selection unit, used to determine the heating stage of the current real-time target sequence, and according to the heating stage of the current real-time target sequence, query the abnormal feature sequence with the same heating stage in the abnormal feature library as the preliminary selection sequence; A candidate unit is used to traverse the preliminary selection sequence, calculate the Euclidean distance between the current wavelet coefficient sequence and each preliminary selection sequence, and take the preliminary selection sequence whose Euclidean distance is less than a first preset value as a candidate sequence; A wavelet entropy unit, used to calculate the current wavelet entropy vector of the current real-time target sequence; A generating unit, used for calculating the similarity between the current wavelet entropy vector and the historical wavelet entropy vector contained in the candidate sequence, and when the similarity between the historical wavelet entropy vector of any candidate sequence and the current wavelet entropy vector is greater than a second preset value, it is determined that the current real-time target sequence has abnormal current fluctuations, and a power-off instruction is generated; Among them, the abnormal feature library includes multiple abnormal feature sequences, each abnormal feature sequence includes: a historical current value sequence formed by a damaged or broken electrode sheet in a certain heating stage, based on the preset wavelet basis function corresponding to the heating stage, the historical current value sequence is subjected to wavelet decomposition to obtain historical approximate wavelet coefficients, historical detail wavelet coefficients and historical wavelet entropy vectors; and the heating stage corresponding to the historical current value sequence.

8. The graphene heating device according to claim 7, characterized in that: The heating stage includes a cold start period, a heating period and a stabilization period arranged in chronological order from the start of the graphene heating device; The wavelet decomposition is performed using a preset wavelet basis function according to the temperature rise stage of the current current value sequence, including: During the cold start period, Haar wavelet is used as the wavelet basis function; During the warming period, Coiflet wavelet was used as the wavelet basis function; In the stable period, Biorthogonal wavelet is used as the wavelet basis function.

9. The graphene heating device according to claim 7, characterized in that: In the wavelet entropy unit, the current wavelet entropy vector of the current real-time target sequence is calculated, including: Extract the detail wavelet coefficient sequence W from the wavelet coefficient sequence x (j,k), j is a positive integer less than or equal to N, and k represents the position number of the detail wavelet coefficient at the jth scale; For the detail wavelet coefficients at each scale, based on formula (1), the relative distribution probability of each detail wavelet coefficient is determined to obtain the probability distribution function of the detail wavelet coefficients at this scale; p j,k Represents the distribution probability of the kth detail wavelet coefficient at the jth scale; Based on the probability distribution function of the detail wavelet coefficients at each scale, the wavelet entropy H at each scale is calculated according to formula (2): j , get the current wavelet entropy vector [H1,H2,…,H j ,…,H N ]; H j =-∑ k p j,k logp j,k (2); H j represents the wavelet entropy at the jth scale.

10. A car seat, characterized in that: A graphene heating device comprising the graphene heating device according to any one of claims 1 to 9.

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