Detection method, system, probe mechanism and equipment for power battery

Abstract

The invention belongs to the technical field of detection, and particularly relates to a detection method, system, probe mechanism and equipment for a power battery, and the detection method for the power battery comprises the steps that a control module controls the probe mechanism to detect a welding position according to the shape of the welding position; a plurality of layers of detection coils are sequentially arranged from top to bottom to form a probe mechanism, one layer of detection coils is independently arranged, the number of the other layers of detection coils is two, the circle center projections of all the detection coils are on the same straight line, and the detection ranges of the two detection coils on the same layer are internally tangent to the detection ranges of the independently arranged detection coils. The projections of the circle centers of the two detection coils on the same layer are located on the two sides of the projection of the circle center of the independently-arranged detection coil, so that the detection coils are arranged in a layered mode, the positions of the detection coils are reasonably arranged, the overlapping area of the detection ranges of the detection coils is minimum, and defect detection on the welding position at different depths is achieved; and the defect detection range of the area around the welding position is also reduced.

Description

Technical Field

[0001] The present invention belongs to the field of detection technology, specifically relates to the field of on-line non-destructive testing instruments, and particularly relates to a detection method, system, probe mechanism and device for power batteries. Background Art

[0002] In workpiece production, welding treatment needs to be performed on the workpiece, and after welding, the welding position needs to be detected. However, when electromagnetic scanning is used to detect defects at the welding position, the detection range of the detection coil varies at different frequencies, resulting in the inability to effectively distinguish the defect signals between the welding area and the non-welding area, and the false detection rate is ≥20%.

[0003] Therefore, since the detection of defects at the welding position is affected by the defects in the surrounding area, it is necessary to design a detection method, system, probe mechanism and device for power batteries.

[0004] It should be noted that the above information disclosed in this background art section is only used to understand the background art of the concept of this application. Therefore, the above description is not considered as information of the prior art. Summary of the Invention

[0005] The embodiments of the present disclosure at least provide a detection method, system, probe mechanism and device for power batteries.

[0006] In a first aspect, the embodiments of the present disclosure provide a detection method for power batteries, including: Obtaining the detection ranges of the detection coils at different frequencies through a control module, and arranging the detection coils according to the detection ranges to form a probe mechanism; Controlling the probe mechanism to detect the welding position according to the shape of the welding position through the control module to determine the situation of the welding position; where The method of arranging the detection coils according to the detection ranges to form a probe mechanism includes: At least two layers of detection coils are arranged one above the other to form a probe mechanism. One layer of detection coil is arranged alone, and the number of detection coils in the remaining layers is two. The frequencies of the detection coils in each layer are different, and the center projections of all the detection coils are on the same straight line. The detection ranges of the two detection coils in the same layer are respectively internally tangent to the detection range of the detection coil arranged alone, and the projections of the centers of the two detection coils in the same layer are located on both sides of the projection of the center of the detection coil arranged alone.

[0007] In an optional implementation manner, the method of obtaining the detection ranges of the detection coils at different frequencies through the control module includes: Obtain a standard part, set a defect positioning point and an initial point on the top surface of the standard part, and set corresponding defect marks at different depths below the defect positioning point, where the defect marks correspond to the detection depths of the detection coil at different frequencies; The control module controls the first moving mechanism to drive the detection coil to move from the initial point to the defect positioning point, and controls the detection coil to operate at one of the frequencies. After the detection coil detects the defect mark, the distance between the center of the detection coil and the defect positioning point at this time is the detection range corresponding to the detection coil at this frequency. Then, obtain the detection ranges corresponding to other frequencies to obtain the detection ranges of the detection coil at different frequencies.

[0008] In an optional implementation manner, the method for the control module to control the probe mechanism to detect the welding position according to the shape of the welding position includes: The control module determines the corresponding detection strategy according to the shape of the welding position. That is, when the shape of the welding position is point-like, the detection strategy is static detection of the probe. When the shape of the welding position is linear, the detection strategy is dynamic detection of the probe.

[0009] In an optional implementation manner, the static detection of the probe includes: The control module controls each detection coil to work in turn. The detection range of the separately set detection coil covers the welding position, and the detection values of two detection coils on the same layer are obtained respectively; If the detection value of one detection coil among the two detection coils on the same layer is slightly abnormal and the detection value of the other detection coil is normal, then there is no defect in the welding position, and the control module determines that the welding position is qualified and the workpiece is qualified at the frequency corresponding to the detection coil of this layer; If only one detection coil among the two detection coils on the same layer has a severely abnormal detection value, the control module determines that the workpiece is unqualified at the frequency corresponding to the detection coil of this layer; When the detection values of both detection coils among the two detection coils on the same layer are slightly abnormal, the control module controls the rotating mechanism to drive the probe mechanism to rotate one circle, and obtains the detection curves corresponding to the two detection coils on the same layer respectively. If the detection values in both detection curves are always slightly abnormal, the control module determines that the welding position is unqualified but the workpiece is qualified at the corresponding frequency. If the detection value is normal in any of the detection curves, it is determined that the welding position is qualified and the workpiece is qualified; If the detection values of both detection coils among the two detection coils on the same layer are severely abnormal, the control module controls the rotating mechanism to drive the probe mechanism to rotate one circle, and obtains the detection curves corresponding to the two detection coils on the same layer respectively. If the detection values in both detection curves are always severely abnormal, the control module determines that the welding position is unqualified but the workpiece is qualified at the corresponding frequency. If the detection value is normal or slightly abnormal in any of the detection curves, it is determined that the workpiece is unqualified; When the detected value is within the first preset threshold, the detected value is normal; when the detected value is within the second preset threshold, the detected value is mildly abnormal; when the detected value is within the third preset threshold, the detected value is severely abnormal. The first preset threshold, the second preset threshold, and the third preset threshold are consecutive thresholds set in ascending order. Regarding the welding position situation, after all the detection coils are working, if the control module determines that the workpiece is abnormal, then the workpiece corresponding to the currently detected welding position is abnormal. If the workpiece is normal but the welding position is unqualified, it is determined that the currently detected welding position is unqualified. Otherwise, it is determined that the welding position is qualified.

[0010] In an alternative embodiment, the dynamic detection of the probe includes: The control module controls each detection coil to work in sequence. The detection range of the individually set detection coil covers the width range of the welding position. The probe mechanism is driven by the second moving mechanism to move repeatedly along the welding position. In one reciprocating process, the two detection coils in the same layer work at the same frequency respectively, constructing a detection curve corresponding to each position point on the welding position and the detected value. The two detection curves are compared. If the position points corresponding to the mildly abnormal detected values in the two detection curves do not coincide, the control module determines that the welding position is qualified. If the position points corresponding to the mildly abnormal detected values in the two detection curves coincide and the detected values are the same, it is determined that the welding position is unqualified. If the detected values are different, the workpiece is picked out, and the position point corresponding to the mildly abnormal detected value is located according to the detection curve, and static detection of the probe is performed on this position point to determine the detection result corresponding to this position point. Regarding the welding position situation, after all the detection coils are working, if the control module determines that the workpiece is abnormal, then the workpiece corresponding to the currently detected welding position is abnormal. If the workpiece is normal but the welding position is unqualified, it is determined that the currently detected welding position is unqualified. Otherwise, it is determined that the welding position is qualified.

[0011] In a second aspect, an embodiment of the present disclosure provides a detection system for a power battery, including: A detection range determination module configured to obtain the detection ranges of the detection coils at different frequencies and arrange the detection coils according to the detection ranges to form a probe mechanism. A detection module configured to control the probe mechanism to detect the welding position according to the shape of the welding position to determine the welding position situation.

[0012] In a third aspect, an embodiment of the present disclosure provides a computer-readable storage medium, on which a computer program / instructions are stored. When the computer program / instructions are executed by a processor, the steps of the above-mentioned method for detecting a power battery are implemented.

[0013] Fourthly, an embodiment of the present disclosure provides a program product including instructions. When the instructions are run on a device, the device is caused to execute the steps of the above-described detection method for a power battery.

[0014] Fifthly, an embodiment of the present disclosure provides a probe mechanism for a power battery, which is provided with at least two layers of detection coils arranged one above the other. One layer of the detection coils is arranged separately, and the number of detection coils in the remaining layers is two each. The frequencies of the detection coils in each layer are different, and the centers of projection of all the detection coils are on the same straight line. The detection ranges of the two detection coils in the same layer are respectively internally tangent to the detection range of the separately arranged detection coil, and the projections of the centers of the two detection coils in the same layer are located on both sides of the projection of the center of the separately arranged detection coil. A switch module is connected to each of the detection coils to control the corresponding detection coil to be turned on or off through the switch module.

[0015] Sixthly, an embodiment of the present disclosure provides a detection device for a power battery, including: a control module, and a probe mechanism electrically connected to the control module. The control module is configured to control the probe mechanism to detect the welding position by using the above-described detection method for a power battery to judge the situation of the welding position.

[0016] The beneficial effects of the present invention are as follows. The detection method for a power battery of the present invention includes: obtaining the detection ranges of the detection coils at different frequencies through a control module, and arranging the detection coils according to the detection ranges to form a probe mechanism; controlling the probe mechanism to detect the welding position according to the shape of the welding position through the control module to judge the situation of the welding position. The method of arranging the detection coils according to the detection ranges to form a probe mechanism includes: arranging at least two layers of detection coils one above the other to form a probe mechanism, where one layer of the detection coils is arranged separately, and the number of detection coils in the remaining layers is two each. The frequencies of the detection coils in each layer are different, and the centers of projection of all the detection coils are on the same straight line. The detection ranges of the two detection coils in the same layer are respectively internally tangent to the detection range of the separately arranged detection coil, and the projections of the centers of the two detection coils in the same layer are located on both sides of the projection of the center of the separately arranged detection coil. Thus, the detection coils are arranged in layers, and the positions of the detection coils are reasonably set, so that the overlapping area of the detection ranges of the detection coils is minimized, realizing defect detection of the welding position at different depths, and also reducing the range of defect detection of the area around the welding position, avoiding the influence of the area around the welding position on the detection of the welding position, and ensuring accurate detection of the welding position.

[0017] Other features and advantages of the present invention will be described in the following specification, and some of them will become obvious from the specification, or be understood by implementing the present invention. The objectives and other advantages of the present invention are achieved and obtained by the structures specifically pointed out in the specification and the drawings.

[0018] To make the above objects, features, and advantages of the present invention more obvious and understandable, preferred embodiments are specifically exemplified herein and described in detail below in conjunction with the accompanying drawings. Description of the Drawings

[0019] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings required for use in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0020] Figure 1 A flowchart of a detection method for a power battery provided by an embodiment of the present disclosure; Figure 2 A schematic diagram of the position of a detection coil provided by an embodiment of the present disclosure; Figure 3 A schematic diagram of a detection range provided by an embodiment of the present disclosure; Figure 4 A schematic diagram of a defect location point and an initial point provided by an embodiment of the present disclosure; Figure 5 A schematic diagram of a detection coil circuit provided by an embodiment of the present disclosure; Figure 6 A schematic diagram of the structure of a probe mechanism and a rotating mechanism provided by an embodiment of the present disclosure.

[0021] In the figure: 1 detection coil, 2 standard part, 3 probe mechanism, 4 rotating mechanism. Specific Embodiments

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0023] As used herein, phrases such as "in one embodiment", "according to one embodiment", "in some embodiments", etc. generally refer to the fact that the specific feature, structure, or characteristic after the phrase can be included in at least one embodiment of the present disclosure. Thus, a specific feature, structure, or characteristic can be included in more than one embodiment of the present disclosure, such that these phrases do not necessarily refer to the same embodiment. As used herein, the terms "example", "exemplary", etc. are used "as an example, instance, or illustration. Any embodiment, aspect, or design described herein as "example" or "exemplary" is not necessarily to be construed as preferred or superior to other embodiments, aspects, or designs. Instead, the use of the terms "example", "exemplary", etc. is intended to present concepts in a concrete manner.

[0024] The sensitivity of the detection coil to detecting defects at different depths is different at different frequencies. Defects refer to impurities, particles, cracks, delaminations, voids, bubbles, pores, etc. Therefore, it is necessary for the detection coil to detect defects at different depths at different frequencies. However, different frequencies will bring about changes in the detection range. When the detection coil operates at a high frequency, the detection range is small and the detection depth is shallow. As the frequency of the detection coil decreases, the detection range becomes larger and the detection depth becomes deeper, resulting in defects outside the detection range being misjudged as defects at the welding position. However, some defects are within the acceptable range for the workpiece but outside the acceptable range for the welding position. For example, impurities, particles, bubbles, etc. can appear in the workpiece but affect the welding effect if they appear at the welding position. Although simulating the probe movement path can reduce this problem to a certain extent, the inventors also found that the size of the welding position will change. Every time the welding position changes, the probe path needs to be recalculated, which is very complicated. At the same time, it is very difficult to achieve fine movement of the probe at the millimeter level. Even if different specifications of probes make the detection ranges of each probe consistent by changing the diameter of the detection coil, changing the specifications will in turn affect the detection depth, and there will be a problem of missing detection depth in a certain section.

[0025] Regarding the defects existing in the above solutions, they are all the results obtained by the inventors through practice and careful research. Therefore, the process of discovering the above problems and the solutions proposed in the present disclosure by the present disclosure for the above problems should be the contributions made by the inventors to the present disclosure during the process of the present disclosure.

[0026] It should be noted that: Similar reference numerals and letters denote similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] The following will describe in detail some embodiments of the present invention with reference to the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0028] AsFigure 1 As shown, at least one disclosed embodiment provides a detection method for a power battery, including: obtaining the detection range of the detection coil 1 at different frequencies through a control module, and arranging the detection coil 1 according to the detection range to form a probe mechanism 3; controlling the probe mechanism 3 to detect the welding position according to the shape of the welding position through the control module to judge the situation of the welding position; wherein the method of arranging the detection coil 1 according to the detection range to form the probe mechanism 3 includes: As Figure 2 and Figure 3 As shown, at least two layers of detection coils 1 are arranged one above the other to form a probe mechanism 3. One layer of the detection coils 1 is arranged separately, and the number of detection coils 1 in the remaining layers is two. The frequency of each layer of detection coils 1 is different, and the center projections of all the detection coils 1 are on the same straight line. The detection ranges of the two detection coils 1 in the same layer are respectively internally tangent to the detection range of the separately arranged detection coil 1, and the projections of the centers of the two detection coils 1 in the same layer are located on both sides of the projection of the center of the separately arranged detection coil 1. Thus, the detection coils 1 are arranged in layers, and the positions of the detection coils 1 are reasonably set so that the overlapping area of the detection ranges of the detection coils 1 is minimized. This not only realizes defect detection of the welding position at different depths but also reduces the range of defect detection of the area around the welding position, avoiding the influence of the area around the welding position on the detection of the welding position and ensuring accurate detection of the welding position.

[0029] As Figure 2 and Figure 3 As shown, the range of the circle with the smallest line width corresponds to the detection range of the lowermost detection coil 1, the range corresponding to the middle line width is the detection range corresponding to the second-layer detection coil 2, and the range corresponding to the outermost line width is the detection range corresponding to the uppermost detection coil 2.

[0030] In this embodiment, the distance between the projections of the centers of the two detection coils 1 in the same layer and the projection of the center of the separately arranged detection coil 1 is the same.

[0031] As Figure 2 and Figure 6 As shown, in this embodiment, the number of layers of the detection coils 1 can be three. The lowermost detection coil 1 is one, and the number of detection coils 1 in the remaining two layers is two. Specifically, the detection coils 1 can be arranged in the probe mechanism 3.

[0032] As Figure 4As shown, in an alternative embodiment, the method for the control module to obtain the detection range of the detection coil 1 at different frequencies includes: obtaining a standard part 2, setting a defect positioning point and an initial point on the top surface of the standard part 2, and setting corresponding defect marks at different depth positions below the defect positioning point, where the defect marks correspond to the detection depths of the detection coil 1 at different frequencies; controlling, by the control module, the first moving mechanism to drive the detection coil 1 to move from the initial point to the defect positioning point, and controlling the detection coil 1 to operate at one of the frequencies. After the detection coil 1 detects the defect mark, the distance between the center of the detection coil 1 and the defect positioning point at this time is the detection range of the detection coil 1 at this frequency. Then, the detection ranges corresponding to other frequencies are obtained to obtain the detection ranges of the detection coil 1 at different frequencies.

[0033] In this embodiment, the standard part 2 is used to determine the detection range of the detection coil 1 at each frequency, and the standard part 2 can be manufactured according to the shape, material, etc. of the workpiece to be detected currently.

[0034] In this embodiment, the first moving mechanism can be a linear motion pair or the like to drive the detection coil 1 to move from the initial point to the defect positioning point.

[0035] In this embodiment, the initial point is A, the defect positioning point is a1, and the corresponding defect marks set at different depth positions below the defect positioning point are a2, a3, and a4 respectively. Each defect mark can correspond to a different frequency. When the detection frequency is the highest, the defect mark a2 can be detected. When the detection frequency is the lowest, the defect mark a4 can be detected. Each detection frequency is more sensitive to the defect mark at the corresponding depth and is not sensitive to the defect marks at other depths, and the defect marks at other depths cannot be detected.

[0036] In this embodiment, r1 is the radius of the detection range when the detection coil 1 operates at the maximum power corresponding to the three defect marks a2, a3, and a4, r3 is the radius of the detection range when the detection coil 1 operates at the minimum power corresponding to the three defect marks a2, a3, and a4, and r2 is the radius of the detection range when the detection coil 1 operates at the intermediate power corresponding to the three defect marks a2, a3, and a4.

[0037] In an alternative embodiment, the method for the control module to control the probe mechanism 3 to detect the welding position according to the shape of the welding position includes: the control module determines the corresponding detection strategy according to the shape of the welding position, that is, when the shape of the welding position is dot-shaped, the detection strategy is static detection of the probe, and when the shape of the welding position is linear, the detection strategy is dynamic detection of the probe.

[0038] In this embodiment, according to the shape of different welding positions, that is, the shape of the solder joints, an appropriate detection strategy is selected, so that the welding positions can be detected more precisely, and a more accurate detection situation of the welding positions can be obtained; for example, when the shape of the welding position is a circle with a diameter ≤ 3 mm, it is determined as a dot shape, and when it is a continuous weld seam with a length ≥ 5 mm and a width ≤ 2 mm, it is determined as a linear shape.

[0039] In this embodiment, the defect judgment criterion for the welding position, combined with the static detection of the probe and the dynamic detection of the probe, can realize the defect judgment of the welding position and the defect judgment around the welding position, and then screen out qualified workpieces, unqualified workpieces, and whether the welding position is qualified.

[0040] In an optional implementation manner, the static detection of the probe includes: the control module controls each detection coil 1 to work in turn, the detection range of the separately provided detection coil 1 covers the welding position, and the detection values of two detection coils 1 in the same layer are respectively obtained; If the detection value of one detection coil 1 in two detection coils 1 in the same layer is slightly abnormal and the detection value of the other detection coil 1 is normal, then there is no defect in the welding position, and the control module determines that the welding position is qualified and the workpiece is qualified at the frequency corresponding to the detection coil 1 of this layer; If only the detection value of one detection coil 1 in two detection coils 1 in the same layer is severely abnormal, the control module determines that the workpiece is unqualified at the frequency corresponding to the detection coil 1 of this layer; When the detection values of both detection coils 1 in two detection coils 1 in the same layer are slightly abnormal, the control module controls the rotating mechanism 4 to drive the probe mechanism 3 to rotate one circle, and obtains the detection curves corresponding to the two detection coils 1 in the same layer respectively. If the detection values in both detection curves are always slightly abnormal, the control module determines that the welding position is unqualified but the workpiece is qualified at the corresponding frequency. If the detection value is normal in any detection curve, it is determined that the welding position is qualified and the workpiece is qualified; If the detection values of both detection coils 1 in two detection coils 1 in the same layer are severely abnormal, the control module controls the rotating mechanism 4 to drive the probe mechanism 3 to rotate one circle, and obtains the detection curves corresponding to the two detection coils 1 in the same layer respectively. If the detection values in both detection curves are always severely abnormal, the control module determines that the welding position is unqualified but the workpiece is qualified at the corresponding frequency. If the detection value is normal or slightly abnormal in any detection curve, it is determined that the workpiece is unqualified; When the detection value is within the first preset threshold, the detection value is normal. When the detection value is within the second preset threshold, the detection value is slightly abnormal. When the detection value is within the third preset threshold, the detection value is severely abnormal. The first preset threshold, the second preset threshold, and the third preset threshold are consecutive thresholds set in ascending order; The welding position situation is as follows. After all the detection coils 1 are working, if the control module determines that the workpiece is abnormal, then the workpiece corresponding to the currently detected welding position is abnormal. If the workpiece is normal but the welding position is unqualified, it is determined that the currently detected welding position is unqualified. Otherwise, it is determined that the welding position is qualified.

[0041] In this embodiment, the detected value is the amplitude of the feedback magnetic field signal, which can determine whether there are defects, and different thresholds correspond to different defects.

[0042] In this embodiment, the rotating mechanism 4 can be a rotating motor, etc., such as a high-precision rotating motor (repeated positioning accuracy ±0.01 mm, model such as Harmonic Drive CSF-17-100), and the acquisition frequency during rotation detection is ≥1000 Hz.

[0043] In this embodiment, the end of the first threshold is connected to the start of the second threshold, and the end of the second threshold is connected to the start of the third threshold. The first threshold range includes the values at both ends, the third threshold range includes the values at both ends, and the second threshold range does not include the values at both ends.

[0044] In this embodiment, the first preset threshold is -5% to 5% of the detected value in the defect-free state of the standard part, the second preset threshold is -10% to -5% and 5% to 10% of the detected value in the slightly defective state of the standard part, and the third preset threshold is below -10% and above 10% of the detected value in the severely defective state of the standard part; the specific range can be adjusted according to the specific situation.

[0045] In this embodiment, the defects corresponding to a slight abnormality can be impurities, particles, and bubbles. These defective workpieces can be accepted, but the welding cannot be accepted. The defects corresponding to a slight abnormality can be cracks, delamination, cavities, and pores. Neither the workpiece nor the welding can be accepted.

[0046] In an optional implementation manner, the dynamic detection of the probe includes: the control module controls each detection coil 1 to work in sequence. The detection range of the separately provided detection coil 1 covers the width range of the welding position. The probe mechanism 3 is driven by the second moving mechanism to move back and forth along the welding position. In one reciprocating process, the two detection coils 1 in the same layer work at the same frequency respectively, constructing a detection curve corresponding to each position point on the welding position and the detected value. The two detection curves are compared. If the position points corresponding to the slightly abnormal detected values in the two detection curves do not coincide, the control module determines that the welding position is qualified. If the position points corresponding to the slightly abnormal detected values in the two detection curves coincide and the detected values are the same, it is determined that the welding position is unqualified. If the detected values are different, the workpiece is picked out, and the position points corresponding to the slightly abnormal detected values are located according to the detection curve, and the probe is statically detected at this position point to determine the detection result corresponding to this position point; The welding position situation is as follows. After all the detection coils 1 are working, if the control module determines that the workpiece is abnormal, then the workpiece corresponding to the currently detected welding position is abnormal. If the workpiece is normal but the welding position is unqualified, it is determined that the currently detected welding position is unqualified. Otherwise, the welding position is determined to be qualified.

[0047] In this embodiment, the second moving mechanism can but is not limited to adopting a three-axis moving pair, etc.

[0048] In this embodiment, the detected value is affected by the specific circuit, so each threshold value can be flexibly adjusted according to the specific situation.

[0049] As Figure 5 shown, in this embodiment, the traditional probe controls the operation of one detection coil 1 or multiple detection coils 1 in a non-physical switching manner. If there is residual eddy current in the detection coil 1, it will affect the detection result. Therefore, each detection coil 1 adopts a physical contact (switch module SW1) switching method, that is, each detection coil 1 is connected with a separate switch module SW1 to overcome the residual eddy current in the detection coil 1. ECC1 is the detection coil 1. A power resistor R1 is connected between the detection coil 1 and the physical contact, which can quickly absorb the residual eddy current. At the same time, SW1 is a physical contact to realize the physical cut-off of the circuit on and off. The J1 end is connected to the detector and the peripheral circuit, and the corresponding detected value is obtained by receiving the electromagnetic signal emitted by the detection coil 1 through the detector. R2 is a detection resistor, which is connected between the power resistor R1 and the detection coil 1 to detect whether there is residual eddy current in the detection circuit. J2 is connected to the peripheral detection circuit and the control module, etc. The detector can also be connected to the control module, etc.

[0050] At least one other publicly disclosed embodiment. A detection system for a power battery includes: a detection range determination module configured to obtain the detection ranges of the detection coils 1 at different frequencies and arrange the detection coils 1 according to the detection ranges to form a probe mechanism 3; a detection module configured to control the probe mechanism 3 to detect the welding position according to the shape of the welding position to determine the welding position situation.

[0051] In this embodiment, the above modules can be virtual modules, and their functional steps are integrated in the control module.

[0052] At least one other publicly disclosed embodiment. A computer-readable storage medium stores computer programs / instructions, and when the computer programs / instructions are executed by a processor, the steps of the above detection method for a power battery are implemented.

[0053] At least one other publicly disclosed embodiment. A program product containing instructions, when the instructions are run on a device, causes the device to execute the steps of the above detection method for a power battery.

[0054] At least one other publicly disclosed embodiment: A probe mechanism 3 for a power battery is provided with at least two layers of detection coils 1 arranged one above the other; one layer of the detection coils 1 is arranged separately, and the number of detection coils 1 in the remaining layers is two. The frequency of each layer of detection coils 1 is different, and the center projections of all the detection coils 1 are on the same straight line. The detection ranges of the two detection coils 1 in the same layer are respectively internally tangent to the detection range of the separately arranged detection coil 1, and the projections of the centers of the two detection coils 1 in the same layer are located on both sides of the projection of the center of the separately arranged detection coil 1; a switch module is connected to each of the detection coils 1 to control the corresponding detection coil 1 to be turned on or off through the switch module.

[0055] At least one other publicly disclosed embodiment: A detection device for a power battery includes: a control module, and a probe mechanism 3 electrically connected to the control module; the control module is configured to control the probe mechanism 3 to detect a welding position by using the above-mentioned detection method for a power battery to judge the situation of the welding position.

[0056] In summary, the detection method for a power battery includes: obtaining the detection ranges of the detection coils 1 at different frequencies through the control module, and arranging the detection coils 1 according to the detection ranges to form the probe mechanism 3; controlling the probe mechanism 3 to detect the welding position according to the shape of the welding position through the control module to judge the situation of the welding position; wherein the method of arranging the detection coils 1 according to the detection ranges to form the probe mechanism 3 includes: arranging at least two layers of detection coils 1 one above the other to form the probe mechanism 3, one layer of the detection coils 1 is arranged separately, and the number of detection coils 1 in the remaining layers is two. The frequency of each layer of detection coils 1 is different, and the center projections of all the detection coils 1 are on the same straight line. The detection ranges of the two detection coils 1 in the same layer are respectively internally tangent to the detection range of the separately arranged detection coil 1, and the projections of the centers of the two detection coils 1 in the same layer are located on both sides of the projection of the center of the separately arranged detection coil 1. Thus, the layered arrangement of each detection coil 1 is realized, and the positions of each detection coil 1 are reasonably set, so that the overlapping area of the detection ranges of each detection coil 1 is minimized, realizing the defect detection of the welding position at different depths, and also reducing the detection range of the defects in the area around the welding position, avoiding the influence of the area around the welding position on the detection of the welding position, and ensuring the accurate detection of the welding position.

[0057] The disclosures and other solutions, examples, embodiments, modules, and functional operations described in this document may be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this document and their structural equivalents, or in a combination of one or more of them. The disclosed content and other embodiments may be implemented as one or more computer program products, i.e., modules of one or more computer program instructions encoded on a tangible and non-transitory computer-readable medium for execution by, or to control the operation of, a data processing apparatus. The computer-readable medium may be a machine-readable storage device, a machine-readable storage substrate, a memory device, a composition of matter affecting a machine-readable propagated signal, or a combination of one or more of them. In addition to hardware, the apparatus may also include code that creates an execution environment for the computer program, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them. A propagated signal is an artificially generated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal, which is generated to encode information for transmission to a suitable receiver device.

[0058] A computer program (also called a program, software, software application, script, or code) may be written in any form of programming language (including a compiled or interpreted language), and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. The program may be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program, or in multiple coordinated files (e.g., files that store one or more modules, subroutines, or portions of code). A computer program may be deployed to be executed on one or more computers that are located at one site or distributed across multiple sites and interconnected by a communication network.

[0059] The processing and logical flows described in this document may be executed by one or more programmable processors that execute one or more computer programs to perform functions by operating on input data and generating output. The processing and logical flows may also be executed by special-purpose logic circuitry, and the apparatus may also be implemented as special-purpose logic circuitry, e.g., an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

[0060] For example, a processor suitable for executing a computer program includes general and special-purpose microprocessors, and any one or more of any type of digital computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The basic components of a computer are a processor that executes instructions and one or more storage devices that store instructions and data. Generally, a computer will also include one or more mass storage devices for storing data, such as, for example, magnetic disks, magneto-optical disks, or optical disks, or is operatively coupled to receive data from a mass storage device or to transfer data to a mass storage device, or both. However, a computer does not necessarily have such devices. Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, including, for example, semiconductor memory devices such as erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and compact disc read-only memory (CD ROM) and digital versatile disc read-only memory (DVD-ROM) discs. The processor and memory may be supplemented by, or incorporated in, special purpose logic circuitry.

[0061] Although several embodiments are provided in the present disclosure, it should be understood that the disclosed systems and methods may be embodied in many other specific forms without departing from the spirit or scope of the present disclosure. The current examples are considered illustrative and not restrictive, and are not limited to the details given. For example, various elements or components may be combined or integrated in another system, or some features may be omitted or not implemented.

[0062] In several embodiments provided herein, it should be understood that the disclosed apparatus and methods may also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the figures show the possible architectures, functions, and operations of apparatuses, methods, and computer program products according to multiple embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than marked in the figures. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and the combinations of blocks in the block diagram and / or flowchart, may be implemented by a dedicated hardware-based system for performing the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

[0063] Inspired by the above ideal embodiments of the present invention, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A detection method for a power battery, characterized in that: include: The detection range of the detection coil (1) at different frequencies is obtained through a control module, and the detection coil (1) is arranged according to the detection range to form a probe mechanism (3); The control module controls the probe mechanism (3) to detect the welding position according to the shape of the welding position, so as to determine the welding position condition; in The method of arranging the detection coil (1) according to the detection range to form a probe mechanism (3) comprises: At least two layers of detection coils (1) are arranged in sequence from top to bottom to form a probe mechanism (3), wherein the detection coils (1) of one layer are arranged individually, and the number of detection coils (1) of the remaining layers are two each, the frequency of each layer of detection coils (1) is different, the projections of the centers of all detection coils (1) are on the same straight line, the detection ranges of the two detection coils (1) of the same layer are arranged to be tangent to the detection range of the individually arranged detection coils (1), and the projections of the centers of the two detection coils (1) of the same layer are located on both sides of the projection of the center of the individually arranged detection coils (1).

2. The power battery detection method according to claim 1, characterized in that: The method for obtaining the detection range of the detection coil (1) at different frequencies by means of a control module comprises: Obtain a standard component (2), set a defect location point and an initial point on the top surface of the standard component (2), and set corresponding defect marks at different depths below the defect location point, wherein the defect marks correspond to the detection depths corresponding to the detection coil (1) at different frequencies; The control module controls the first moving mechanism to drive the detection coil (1) to move from the initial point to the defect location point, and controls the detection coil (1) to operate at one of the frequencies. After the detection coil (1) detects the defect mark, the distance between the center of the detection coil (1) and the defect location point is the detection range corresponding to the detection coil (1) at the frequency. Then, the detection ranges corresponding to other frequencies are obtained to obtain the detection ranges of the detection coil (1) at different frequencies.

3. The power battery detection method according to claim 1, characterized in that: The method of controlling the probe mechanism (3) to detect the welding position by the control module according to the shape of the welding position comprises: The control module determines the corresponding detection strategy according to the shape of the welding position, that is, when the shape of the welding position is point-shaped, its detection strategy is static detection of the probe, and when the shape of the welding position is linear, its detection strategy is dynamic detection of the probe.

4. The power battery detection method according to claim 3, characterized in that: The probe static detection includes: The control module controls each detection coil (1) to work in sequence, the detection range of the individually set detection coil (1) covers the welding position, and the detection values ​​of the two detection coils (1) on the same layer are respectively obtained; If the detection value of one detection coil (1) of the two detection coils (1) on the same layer is slightly abnormal, and the detection value of the other detection coil (1) is normal, then there is no defect at the welding position, and the control module determines that the welding position is qualified and the workpiece is qualified at the frequency corresponding to the detection coil (1) on the layer; If the detection value of only one detection coil (1) among the two detection coils (1) on the same layer is severely abnormal, the control module determines that the workpiece is unqualified at the frequency corresponding to the detection coil (1) on the layer; If the detection values ​​of the two detection coils (1) in the same layer are both slightly abnormal, the control module controls the rotating mechanism (4) to drive the probe mechanism (3) to rotate one circle, and obtains the detection curves corresponding to the two detection coils (1) in the same layer. If the detection values ​​in the two detection curves are always slightly abnormal, the control module determines that the welding position is unqualified but the workpiece is qualified at the corresponding frequency. If the detection value in any detection curve is normal, the control module determines that the welding position is qualified and the workpiece is qualified. If the detection values ​​of the two detection coils (1) in the same layer are both severely abnormal, the control module controls the rotating mechanism (4) to drive the probe mechanism (3) to rotate one circle, and obtains the detection curves corresponding to the two detection coils (1) in the same layer. If the detection values ​​in the two detection curves are always severely abnormal, the control module determines that the welding position is unqualified but the workpiece is qualified at the corresponding frequency. If the detection value in any detection curve is normal or slightly abnormal, the workpiece is determined to be unqualified. When the detection value is within the first preset threshold, the detection value is normal; when the detection value is within the second preset threshold, the detection value is slightly abnormal; when the detection value is within the third preset threshold, the detection value is severely abnormal, and the first preset threshold, the second preset threshold and the third preset threshold are continuous thresholds set in order from small to large; The welding position situation is that, after all the detection coils (1) are working, if the control module determines that the workpiece is abnormal, then the workpiece corresponding to the welding position currently being detected is abnormal; if the workpiece is normal but the welding position is unqualified, it is determined that the welding position currently being detected is unqualified; otherwise, it is determined that the welding position is qualified.

5. The power battery detection method according to claim 4, characterized in that: The probe dynamic detection includes: The control module controls each detection coil (1) to work in sequence, and the detection range of the independently set detection coil (1) covers the width range of the welding position. The second moving mechanism drives the probe mechanism (3) to move repeatedly along the welding position. In one reciprocating process, the two detection coils (1) on the same layer work at the same frequency respectively, and construct a detection curve corresponding to each position point on the welding position and the detection value. The two detection curves are compared. If the position points corresponding to the slightly abnormal detection values ​​in the two detection curves do not overlap, the control module determines that the welding position is qualified. If the position points corresponding to the slightly abnormal detection values ​​in the two detection curves overlap and the detection values ​​are consistent, the welding position is determined to be unqualified. If the detection values ​​are inconsistent, the workpiece is picked out, and the position point corresponding to the slightly abnormal detection value is located according to the detection curve, and the probe static detection is performed on the position point to determine the detection result corresponding to the position point. The welding position situation is that, after all the detection coils (1) are working, if the control module determines that the workpiece is abnormal, then the workpiece corresponding to the welding position currently being detected is abnormal; if the workpiece is normal but the welding position is unqualified, it is determined that the welding position currently being detected is unqualified; otherwise, it is determined that the welding position is qualified.

6. A power battery detection system, characterized in that: include: A detection range determination module, configured to obtain the detection range of the detection coil (1) at different frequencies, and to arrange the detection coil (1) according to the detection range to form a probe mechanism (3); The detection module is configured to control the probe mechanism (3) to detect the welding position according to the shape of the welding position, so as to determine the condition of the welding position.

7. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the steps of the power battery detection method according to any one of claims 1 to 5 are implemented.

8. A program product comprising instructions, characterized in that When the instruction is executed by the device, the device executes the steps of the power battery detection method according to any one of claims 1 to 5.

9. A probe mechanism (3) for a power battery, characterized in that: At least two layers of detection coils (1) are arranged in sequence from top to bottom; The detection coils (1) of one layer are individually arranged, and the number of detection coils (1) of the remaining layers are two each. The frequencies of the detection coils (1) of each layer are different. The center projections of all the detection coils (1) are on the same straight line. The detection ranges of the two detection coils (1) of the same layer are respectively arranged to be tangent to the detection range of the individually arranged detection coil (1), and the projections of the center of the two detection coils (1) of the same layer are located on both sides of the projection of the center of the individually arranged detection coil (1). The detection coils (1) are all connected to a switch module, so as to control the corresponding detection coil (1) to be turned on or off through the switch module.

10. A power battery testing device, characterized in that: include: A control module, and a probe mechanism (3) electrically connected to the control module; The control module is configured to control the probe mechanism (3) to detect the welding position using the power battery detection method according to any one of claims 1 to 5, so as to determine the welding position condition.

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