Detection and real-time feedback system for welding defects of energy storage system

Abstract

The invention belongs to the technical field of energy storage systems, and relates to a welding defect detection method and system for dense welding spots in an energy storage system. Comprising a data acquisition module, a data processing module and a data alarm module. After welding is completed, through a pulse current impact mode, changes of current and temperature are detected in real time, and a comprehensive judgment index is constructed so as to judge whether welding defects such as resistance abnormity exist in a welding spot or not. Compared with a traditional detection mode, in the scheme, the resistance value of the welding point and the possible change range of the resistance are obtained by directly detecting the mutual influence quantity of the current and the temperature, and therefore whether the welding point affects normal operation of a follow-up energy storage system or not is accurately judged.

Description

Technical Field

[0001] This paper deals with the detection and real-time feedback system of welding defects in energy storage systems. Background Art

[0002] Energy storage systems, especially large and medium-sized ones, have densely distributed welds. Traditional weld defect detection methods, such as visual inspection, ultrasonic testing, and X-ray testing, are not very convenient for quality inspection of these densely distributed welds in energy storage systems.

[0003] Furthermore, the greatest potential risk to energy storage systems in the later stages of solder joint quality lies in the possibility of abnormal resistance at the solder joint, which could affect the safety of the overall energy storage system circuit. While structural strength requirements are generally low, existing testing methods rarely assess solder joint quality from the perspective of current. Even those that do exist typically monitor current during operation to assess overall energy storage system safety. However, there is limited research on the targeted detection of solder joint locations using current. Summary of the Invention

[0004] The purpose of this invention is to provide a system for detecting and providing real-time feedback on welding defects in energy storage systems. When a welding point is completed, a high current shock is immediately applied to the weld site to monitor the weld location. By monitoring the local resistance and temperature in real time, the location of the weld defect and its severity can be determined and feedback can be provided in a timely manner. The following is a specific solution:

[0005] A detection and real-time feedback system for welding defects in an energy storage system, comprising a data acquisition module, a data processing module, and a data alarm module;

[0006] The data acquisition module includes temperature sensors distributed at the welding point positions, a pulse current impact module, and a current detection module;

[0007] The data processing module receives the real-time data collected by the data acquisition module, calculates the original data, and obtains the comprehensive judgment index J', which is the final comprehensive judgment index. Its value sets the safety range (J' min , J' max ), if it exceeds the range, it is determined that there is a safety hazard at the welding point.

[0008] The data alarm module determines whether to issue an audible and visual alarm or an information alarm based on the value of the comprehensive judgment index J'.

[0009] The detection steps are as follows:

[0010] S1. After welding is completed, a temperature sensor is installed at the welding point to detect the temperature of the welding point. When the temperature of the welding point reaches room temperature, a pulse current is passed through the circuit where the welding point is located, and real-time current and temperature signals are collected;

[0011] S2. The data processing module receives the real-time data collected by the data acquisition module, calculates the comprehensive judgment index J', turns off the pulse current, stores the processed data information, and determines whether an alarm is needed.

[0012] Among them, the calculation formula of the comprehensive judgment index J' is as follows:

[0013]

[0014] α represents the temperature rise rate, which is calculated as

[0015] Where α represents the temperature rise rate, and α is calculated as

[0016] I is the initial current intensity, ω I To adjust the parameters, ΔI is the change in current, c represents the specific heat capacity of the material corresponding to the welding point (non-weld material), σ is the electrical conductivity of the welding point material, A is the cross-sectional area of the welding point, T is the final temperature at the end, K is the thermal conductivity of the welding point material, l is the length of the welding point, μ kl is the heat conduction related constant.

[0017] At the same time, the welding parameters are introduced, welding speed u, welding pressure P, welding time t w If the welding process is completed by personnel, enter the corresponding value according to the corresponding welding conditions.

[0018] For welding speed u, set the heat correction factor To consider the effect of welding speed on heat dissipation at the weld, γ u The value range is (0, 1).

[0019] For welding pressure P, set the influence constant ε P With reference value P0, where ε P The value of is (0, 1), and the reference value P0 is the guiding value in the national standard or industry or enterprise standard.

[0020] For the welding time t w , set the influence constant A constant used to adjust the heat dissipation at the weld during welding time, with a value between (0, 1).

[0021] In order to facilitate current personnel and related personnel to obtain data information in a timely manner, the data alarm module is provided with a wireless communication unit, which sends real-time information on welding defects to the mobile terminal or fixed terminal of the production manager or operator.

[0022] To protect the energy storage module from damage, the current detection module is equipped with a filter inductor and a current stabilizing capacitor. The filter inductor is used to control current fluctuations, and the current stabilizing capacitor is used to prevent large current shocks from damaging the energy storage module.

[0023] To further amplify defects and prevent them from going undetected, the current is increased as regional resistance increases during the inspection process. This amplifies the impact of the defect. Specific judgment parameters include current and temperature.

[0024] When the ΔI value at a certain location changes significantly, further amplification detection is performed:

[0025] S51. If the current value rises faster than the normal rate, it is determined that the resistance is too small, and the pulse current is reduced to protect the circuit.

[0026] S52. If the current value rises at a slower rate than the normal rate, it is determined that the resistance here is too large. In this case, the pulse current is increased to amplify the impact of the defect here.

[0027] When the α value at a certain location changes significantly, further zoom detection is performed:

[0028] S61. If the temperature rise rate exceeds the normal rate, it is determined that the resistance at this location is too large. In this case, the pulse current is increased to amplify the impact of the defect at this location.

[0029] S62. If the temperature rise rate is lower than the normal rate, it is determined that the resistance here is too small. At this time, the pulse current is reduced to save detection time.

[0030] To facilitate data storage and automated control of subsequent production processes to improve yield, the system includes a data exchange interface with external devices. This data exchange interface is connected to the production equipment control system of the energy storage system. When a welding defect is detected, control instructions are automatically sent to the production equipment to adjust the welding process parameters.

[0031] In addition, this solution can also be integrated into a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the steps of the energy storage system welding defect detection and real-time feedback system described above.

[0032] Beneficial effects:

[0033] Compared with traditional detection methods, this solution directly detects the mutual influence of current and temperature to obtain the resistance value at the solder joint and the possible range of resistance variation, thereby accurately determining whether the solder joint will affect the normal operation of the subsequent energy storage system.

[0034] After the welding process is complete, problems can be promptly identified and reported, significantly shortening the inspection cycle. This allows for real-time adjustments to subsequent welding parameters, avoiding extensive rework later in the process, improving production efficiency, and ensuring the production schedule for the energy storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The present invention is a flow chart of a detection and real-time feedback system for welding defects of an energy storage system. DETAILED DESCRIPTION

[0036] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to embodiments and drawings. The embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0037] Example 1:

[0038] Application scenario: During a large-scale photovoltaic energy storage power station construction project, the quality of the welds at the internal connections of the energy storage equipment needs to be inspected. After welding is completed, the current intensity passing through the welds is monitored in real time.

[0039] When the welding point of the equipment is completed, the data acquisition module obtains the relevant parameters of the welding position through pulse current impact. The data processing module receives the real-time data collected in the data acquisition module, calculates the original data, and obtains the comprehensive judgment index J'.

[0040] The calculation formula of the comprehensive judgment index J' is as follows:

[0041]

[0042] Initial temperature T0 = 20 °C, final temperature T = 126 °C, time variation Δt = 5s, temperature rise rate α = 21.3 °C / s, initial current intensity 2A, adjustment parameter ω I =0.1, the change in current ΔI=2A, the specific heat capacity of the material corresponding to the welding point c=460J / (Kg·℃), the electrical conductivity of the welding point material σ=5.96*10 7 S / m, the thermal conductivity of the solder joint material is K = 401W / (m·K), and the cross-sectional area of the solder joint is A = 1*10 -6 m 2 , the length of the solder joint is l = 0.01m, the heat conduction related constant μ kl =0.01, welding speed u=2mm / s, welding pressure P=50MPa, reference value P0 is 50MPa, welding time t w is 3s, where γ u , ε P 、 The values are 0.2, 0.05, and 0.1 respectively. The final J' index value is 132190.99. Generally, in this scenario, the safety range is designed to be between (98000, 150000), which meets the safety requirements.

[0043] Example 2:

[0044] Application scenario: Inspecting the quality of welds in a certain automotive energy storage battery. After welding is completed, the current intensity passing through the weld is monitored in real time.

[0045] When the welding point of the equipment is completed, the data acquisition module obtains the relevant parameters of the welding position through pulse current impact. The data processing module receives the real-time data collected in the data acquisition module, calculates the original data, and obtains the comprehensive judgment index J'.

[0046] The calculation formula of the comprehensive judgment index J' is as follows:

[0047]

[0048] Initial temperature T0 = 25°C, final temperature T = 55°C, time variation Δt = 3s, temperature rise rate α = 10°C / s, initial current intensity 1A, adjustment parameter ω I =0.1, the change in current ΔI=0.5A, the specific heat capacity of the material corresponding to the welding point position c=385J / (Kg·℃), the conductivity of the welding point material σ=3.5*10 7 S / m, the thermal conductivity of the solder joint material is K = 250W / (mK), and the cross-sectional area of the solder joint is A = 0.5*10 -6 m 2 , the length of the solder joint is l = 0.005m, the heat conduction related constant μ kl =0.005, welding speed u=1.5mm / s, welding pressure P=30MPa, reference value P0 is 50MPa, welding time t w is 2s, where γ u , ε P 、 The values are 0.15, 0.03, and 0.08 respectively. The final J' index value is 12729.01. Generally, in this scenario, the safety range is designed to be between (10000, 15000), which meets the safety requirements.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. Energy storage system welding defect detection and real-time feedback system, characterized by: Including data acquisition module, data processing module and data alarm module; The data acquisition module includes temperature sensors distributed at the welding point positions, a pulse current impact module, and a current detection module; The data processing module receives the real-time data collected by the data acquisition module, calculates the original data, and obtains the comprehensive judgment index J'; The data alarm module determines whether to issue an audible and visual alarm or an information alarm based on the value of the comprehensive judgment index J'; The detection steps are as follows: S1. After welding is completed, a temperature sensor is installed at the welding point to detect the temperature of the welding point. When the temperature of the welding point reaches room temperature, a pulse current is passed through the circuit where the welding point is located, and real-time current and temperature signals are collected; S2. The data processing module receives the real-time data collected by the data acquisition module, calculates the comprehensive judgment index J', turns off the pulse current, stores the processed data information, and determines whether an alarm is needed.

2. The energy storage system welding defect detection and real-time feedback system according to claim 1 is characterized in that: The calculation formula of the comprehensive judgment index J' is as follows: α represents the temperature rise rate, which is calculated as I is the initial current intensity, ω I To adjust the parameters, ΔI is the change in current, c represents the specific heat capacity of the material at the welding point, σ is the electrical conductivity of the welding point material, A is the cross-sectional area of the welding point, T is the final temperature at the end, K is the thermal conductivity of the welding point material, l is the length of the welding point, μ kl is the heat conduction related constant, u is the welding speed, P is the welding pressure, t w is the welding time; γ u , ε P 、 are the influencing constants of welding speed, welding pressure and welding time, respectively, and their value ranges are (0, 1). P0 is the guiding value.

3. The energy storage system welding defect detection and real-time feedback system according to claim 2, characterized in that: The data alarm module is provided with a wireless communication unit, which sends real-time information of welding defects to the mobile terminal or fixed terminal of the production manager or operator.

4. The energy storage system welding defect detection and real-time feedback system according to claim 2 or 3, characterized in that: The current detection module is provided with a filter inductor and a current stabilizing capacitor.

5. The energy storage system welding defect detection and real-time feedback system according to claim 4, characterized in that: When the ΔI value at a certain location changes significantly, further amplification detection is performed: S51. If the current value rises faster than the normal rate, it is determined that the resistance is too small, and the pulse current is reduced to protect the circuit. S52. If the current value rises at a slower rate than the normal rate, it is determined that the resistance here is too large. In this case, the pulse current is increased to amplify the impact of the defect here.

6. The energy storage system welding defect detection and real-time feedback system according to claim 2, characterized in that: When the α value at a certain location changes significantly, further zoom detection is performed: S61. If the temperature rise rate exceeds the normal rate, it is determined that the resistance at this location is too large. In this case, the pulse current is increased to amplify the impact of the defect at this location. S62. If the temperature rise rate is lower than the normal rate, it is determined that the resistance here is too small. At this time, the pulse current is reduced to save detection time.

7. The energy storage system welding defect detection and real-time feedback system according to claim 2, characterized in that: It includes a data interaction interface with external equipment, which is connected to the production equipment control system of the energy storage system. When a welding defect is detected, a control instruction is automatically sent to the production equipment to adjust the welding process parameters.

8. A computer-readable storage medium having a computer program stored therein, characterized in that: When the computer program is executed by a processor, the steps of the energy storage system welding defect detection and real-time feedback system as claimed in any one of claims 1 to 7 are implemented.

Images