A method for adaptive adjustment of electroplating conductive power based on rotation of an electroplating hanger

Abstract

The application discloses a kind of based on electroplating hanger rotation electroplating conduction power self-adapting regulation method, comprising: in the real-time acquisition rotation phase signal when hanger continuous rotation, and the physical parameter signal of contact state between hanger and conduction seat is synchronously collected;Extract the contact state change feature associated with rotation phase, calculate the real-time conduction ability evaluation value of each phase point in current rotation period;The evaluation value is compared with the preset conduction ability reference value, if lower than reference value, it is judged as contact weak interval, generates the first instruction of reducing rectifier output current, otherwise, generate the second instruction of improving rectifier output current;According to the above instruction, real-time adjustment rectifier output current makes it follow the contact state periodic change of hanger rotation phase.The application actively reduces current in contact weak interval to avoid spark erosion and save electric energy, actively increases current in close interval to speed up deposition rate, to improve plating layer quality uniformity and prolong hanger life.

Description

Technical Field

[0001] This invention relates to the field of adaptive adjustment technology in electroplating, and in particular to an adaptive adjustment method for electroplating conductivity power based on the rotation of electroplating fixtures. Background Technology

[0002] In existing electroplating operations, a common method is to use a rack to support the workpiece and rotate it continuously within the plating tank to achieve a uniform plating layer distribution. However, under the actual condition of dynamic rack rotation, the mechanical contact state between the rack and the fixed conductive base is not constant but fluctuates periodically with the alternation of rotation phases. Specifically, when the rack rotates to a specific angle, its contact area with the conductive base reaches its maximum and the contact is tight, resulting in optimal conductivity. Conversely, when the rack rotates to the transition region, the contact area decreases, the contact becomes looser, and the conductivity significantly declines. This periodic fluctuation in the mechanical contact state directly leads to a regular alternation of strong and weak conductivity with the rotation phase. To address this issue, some existing technologies attempt to optimize contact stability through structural improvements, such as adding elastic clamping devices, using multi-point contact conductive structures, or using wear-resistant conductive materials, in order to reduce the amplitude of contact fluctuations at the mechanical level. Other solutions focus on improving the rectifier output mode, employing constant current control or a strategy of periodically outputting electrical energy according to a fixed time sequence, attempting to compensate for the instability of mechanical contact through stable electrical output.

[0003] However, the aforementioned existing technical solutions still have significant drawbacks in practical applications. On the one hand, simply relying on mechanical structure improvements cannot completely eliminate the dynamic fluctuations in the contact state, and elastic elements suffer from fatigue relaxation after long-term use, with their stability and reliability gradually deteriorating over time. On the other hand, constant current control or fixed-time output strategies completely ignore the direct interference of real-time changes in the contact state during mechanical rotation on power transmission efficiency. Specifically, in areas with weak contact, the conductive area decreases and the contact becomes loose. If the rectifier blindly outputs a large current at a constant value or fixed time, the excess electrical energy cannot be effectively used for electrochemical reactions but is converted into Joule heat that accumulates at the contact points, causing a sharp increase in local temperature. This can accelerate oxidation and corrosion of the contact surface, or even cause arcing and burning of the mounting bracket and conductive base, resulting in serious energy waste and plating scorching defects. Conversely, in the close contact area, the contact resistance is the lowest and the conductivity is the best, which should be a favorable time to input a large current to accelerate the deposition rate. However, the existing solution fails to identify and utilize the high conductivity in this area, and still maintains a low current level, which makes it impossible to increase the deposition rate, significantly slows down the overall production efficiency, and fails to give full play to the production capacity advantage of the equipment. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the mismatch between the periodic fluctuation of mechanical contact state caused by the rotation of the electroplating rack and the blind constant output of the rectifier in the prior art, which leads to heat generation and erosion and energy waste when the contact is weak, and low deposition efficiency when the contact is tight. The present invention provides an adaptive adjustment method for electroplating conductive power based on the rotation of the electroplating rack, so that the output power of the rectifier can be dynamically adjusted in real time according to the contact state change of the rack rotation phase. It can actively reduce the current in the weak contact area to avoid arcing and erosion and save energy, and actively increase the current in the tight contact area to make full use of the conductivity advantage to accelerate the deposition speed, thereby improving the uniformity of electroplating quality, extending the service life of the rack and improving the overall production efficiency.

[0005] To address the aforementioned technical problems, this invention provides a method for adaptive adjustment of electroplating conductivity power based on the rotation of an electroplating fixture, comprising the following steps: During the continuous rotation of the electroplating rack, the rotation phase signal of the rack is acquired in real time, and physical parameter signals characterizing the contact state between the rack and the conductive base are collected simultaneously. Based on the rotation phase signal and physical parameter signal, the contact state change characteristics associated with the rotation phase are extracted, and based on the contact state change characteristics, the real-time conductivity assessment value corresponding to each phase point in the current rotation cycle is calculated. The real-time conductivity assessment value is compared with the preset conductivity benchmark value; If the real-time conductivity assessment value is lower than the conductivity benchmark value, the current phase is determined to be in the weak contact range, and a first power regulation command is generated to reduce the rectifier output current. If the real-time conductivity assessment value is not lower than the conductivity benchmark value, then the current phase is determined to be in the close contact range, and a second power regulation command is generated to increase the rectifier output current. According to the first power adjustment command or the second power adjustment command, the output current value of the rectifier is adjusted in real time so that the output power of the rectifier changes with the periodic contact state change of the rotation phase of the hanger.

[0006] In one embodiment of the present invention, the physical parameter signal characterizing the contact state between the hanger and the conductive base is the dynamic contact resistance value between the hanger and the conductive base; the specific method for synchronously acquiring the physical parameter signal characterizing the contact state between the hanger and the conductive base is as follows: A voltage sampling terminal is set on the rotating shaft of the hanger, and a current sampling terminal is set on the conductive base. The real-time voltage drop and real-time conduction current between the hanger and the conductive base are collected synchronously at a preset sampling frequency, and the dynamic contact resistance value is calculated.

[0007] In one embodiment of the present invention, based on the contact state change characteristics, the real-time conductivity assessment value corresponding to each phase point within the current rotation cycle is calculated, specifically including: Using a complete rotation cycle as the calculation window, the dynamic contact resistance value corresponding to each sampling moment within the rotation cycle is extracted to form a resistance-phase sequence of contact resistance as a function of phase angle. Determine the cycle time of one rotation of the hanger based on its rotation speed; The arithmetic mean of all dynamic contact resistance values ​​collected within the period is used as the reference resistance value of the period. The dynamic contact resistance value at each sampling moment is divided by the reference resistance value to obtain the normalized resistance ratio. Taking the reciprocal of the normalized resistance ratio yields the normalized contact conductivity. The real-time conductivity assessment value is the normalized contact conductivity value of each phase point. The larger the normalized contact conductivity value, the stronger the conductivity of the phase point.

[0008] In one embodiment of the present invention, the preset conductivity reference value is determined in advance by the following method: The fixture is rotated at the same speed as during actual electroplating under no-load conditions without any electroplated workpieces loaded, and the dynamic contact resistance values ​​of each phase point are collected within a complete rotation cycle. The instantaneous contact conductance at each phase point is obtained by taking the reciprocal of the dynamic contact resistance value at each phase point. The arithmetic mean of the instantaneous contact conductance values ​​at each phase point is used as the baseline mean. The instantaneous contact conductance values ​​at each phase point are then divided by the baseline mean to obtain the no-load normalized contact conductance values ​​at each phase point. The no-load normalized contact conductivity value of each phase point is used as the preset conductivity benchmark value of the phase point.

[0009] In one embodiment of the present invention, the real-time conductivity assessment value is compared with a preset conductivity benchmark value, specifically as follows: The real-time conductivity assessment value at the current sampling time is compared with the no-load normalized contact conductivity value corresponding to the phase angle at the current sampling time. The real-time conductivity assessment value is the normalized contact conductivity value. If the real-time conductivity assessment value at the current sampling time is less than the no-load normalized contact conductivity value corresponding to the phase angle, it is determined that the current contact is in a weak range, and a first power regulation command is generated to reduce the rectifier output current. If the real-time conductivity assessment value at the current sampling time is greater than or equal to the no-load normalized contact conductivity value corresponding to the phase angle, it is determined that the current contact is in the tight contact range, and a second power regulation command for increasing the rectifier output current is generated.

[0010] In one embodiment of the present invention, generating a first power regulation command for reducing the rectifier output current specifically includes: When the real-time conductivity assessment value is less than the no-load normalized contact conductance value corresponding to the phase angle, but greater than or equal to 90% of the no-load normalized contact conductance value corresponding to the phase angle, a first power regulation command is generated to reduce the current output current value of the rectifier to 95% of the current output current value. When the real-time conductivity assessment value is less than 90% of the no-load normalized contact conductivity value corresponding to the phase angle, a first power regulation command is generated to reduce the current output current value of the rectifier to 85% of the current output current value.

[0011] In one embodiment of the present invention, generating a second power regulation command for increasing the rectifier output current specifically includes: When the real-time conductivity assessment value is greater than or equal to the no-load normalized contact conductivity value corresponding to the phase angle, the ratio of the real-time conductivity assessment value to the no-load normalized contact conductivity value is calculated to obtain the contact conductivity margin ratio. Based on the contact conductivity margin, the target output current value of the rectifier is determined as follows: I t =I c ·(1+α·(R c -1)); Among them, I t For the target output current value, I c R is the current output current value. c The contact conductivity margin is α, which is a preset current compensation coefficient with a value range of 0.3 to 0.7. The value of α is negatively correlated with the temperature of the current electroplating solution. Generate a second power regulation command to increase the rectifier's output current to the target output current value.

[0012] In one embodiment of the present invention, the output current value of the rectifier is adjusted in real time so that the output power of the rectifier changes with the periodic contact state change of the rotation phase of the hanger, specifically including: A table is pre-established to correspond to each phase point of the fixture and the output current value of the rectifier within a complete rotation cycle. Each phase angle in the table corresponds to a preset output current value. Once the rotation phase angle at the current sampling moment is obtained, the preset output current value that matches the rotation phase angle is queried in the corresponding relationship table, and the current output current value of the rectifier is adjusted to the preset output current value. Each time the hanger completes a full cycle of rotation, the preset output current value corresponding to each phase angle in the corresponding relationship table is updated based on the contact state change characteristics collected in the current cycle, so as to improve the matching degree between the output current of the next cycle and the contact state change characteristics.

[0013] In one embodiment of the present invention, the method further includes: continuously monitoring the thickness of the deposited metal layer during the process of adjusting the output current, and outputting a control signal to stop electroplating when the thickness of the deposited metal layer reaches a preset target thickness.

[0014] The technical solution of the present invention has the following advantages compared with the prior art: The electroplating conductivity power adaptive adjustment method based on electroplating rack rotation described in this invention effectively avoids local overheating, ablation, energy waste, and plating defects caused by blindly outputting large current in areas of weak contact by real-time monitoring of the contact state between the rack and the conductive base and adaptively adjusting the rectifier output current according to its periodic changes. At the same time, in areas of tight contact, the system can increase the current in a timely manner to make full use of the high conductivity, thereby improving the metal deposition rate, optimizing the electroplating quality, and significantly improving the overall production efficiency. Attached Figure Description

[0015] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein: Figure 1 This is a flowchart of the steps of the electroplating conductivity power adaptive adjustment method based on electroplating rack rotation of the present invention. Figure 2 This is a flowchart of the steps of the present invention to collect physical parameter signals characterizing the contact state between the hanger and the conductive base; Figure 3 This is a flowchart of the steps for calculating the real-time conductivity assessment value according to the present invention; Figure 4 This is a flowchart of the steps for determining a preset conductivity benchmark value according to the present invention; Figure 5 This is a flowchart of the steps of comparing real-time conductivity assessment values ​​with preset conductivity benchmark values ​​according to the present invention. Figure 6 This is a flowchart of the steps for generating the first power regulation command according to the present invention; Figure 7 This is a flowchart of the steps for generating the second power regulation command according to the present invention; Figure 8 This is a flowchart illustrating the steps of adjusting the output current value of the rectifier in real time according to the present invention. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0017] Reference Figure 1 As shown, in order to address the mismatch between the periodic fluctuations in the contact state caused by mechanical rotation and the blind output of the rectifier in the prior art, this invention provides an adaptive adjustment method for electroplating conductive power based on the rotation of the electroplating fixture. The core technical concept of this method is to establish a dynamic linkage relationship between the real-time rotation phase of the fixture and the power output timing of the rectifier, so that the output power can actively follow the changes in the contact state and adaptively adjust, thereby achieving coordinated matching between the mechanical motion state and the electrical control strategy.

[0018] Specifically, this invention first acquires the rotation phase signal in real time during the continuous rotation of the hanger, which reflects the current spatial angular position of the hanger; simultaneously, it also acquires physical parameter signals that characterize the contact state between the hanger and the conductive base, which directly or indirectly reflect the conductivity under the current contact conditions. By correlating the rotation phase at the same moment with the physical parameters of the contact state, the periodic change characteristics of the contact state with the rotation phase can be extracted, that is, a phase-contact state mapping relationship can be established.

[0019] Based on this mapping relationship, a real-time conductivity assessment value is calculated for each phase point within the current rotation cycle. This assessment value quantifies the actual conductivity level of the hanger at different rotation angles. Furthermore, this invention introduces a preset conductivity benchmark value as a judgment threshold, representing a reference boundary for judging the quality of contact. The real-time calculated conductivity assessment value is compared phase-by-phase with this benchmark value: when the assessment value is lower than the benchmark value, it indicates that the current phase is in a weak range with small contact area and loose contact. Continuing to input a large current at this point will lead to the aforementioned problems of heating, erosion, and energy waste. Therefore, a first power adjustment command is generated to reduce the rectifier output current. When the assessment value is not lower than the benchmark value, it indicates that the current phase is in the optimal conductivity range with large contact area and tight contact. At this point, this favorable condition should be fully utilized, and a second power adjustment command is generated to increase the rectifier output current, thereby accelerating the electroplating deposition speed.

[0020] Ultimately, the rectifier's output current value is adjusted in real time according to the aforementioned power regulation command. Throughout the entire rotation cycle, the rectifier's output power dynamically increases or decreases in accordance with the contact state changes corresponding to the rotation phase of the fixture, achieving adaptive and coordinated control by reducing the current when the contact is weak to avoid ablation and save energy, and increasing the current when the contact is tight to improve deposition efficiency.

[0021] Through the above technical solution, the present invention can achieve the following beneficial effects: First, by actively reducing the current output in the weak contact area, the phenomenon of local heating and arcing caused by poor contact due to large current is avoided from the source of electrical control, which significantly improves the service life of the hanger and the conductive base, while reducing the consumption of ineffective power and reducing the energy consumption cost of the process. Secondly, by actively increasing the current output in the close contact area, the electrochemical deposition efficiency under optimal conductivity conditions is fully utilized, effectively shortening the overall electroplating time and significantly improving production efficiency and equipment utilization. Third, due to the real-time matching of the rectifier output power and the rotation phase of the hanger, the current density distribution in the entire electroplating process is more uniform and reasonable, avoiding the problem of local scorching or uneven thickness of the plating layer caused by sudden current changes or contact fluctuations. This is conducive to obtaining a high-quality plating layer with dense structure and consistent thickness, providing reliable process assurance for high-end electroplated workpieces, including key components of cranes.

[0022] This invention fundamentally overcomes the drawbacks of the separation between mechanical motion and electrical control in traditional solutions, integrating the mechanical behavior of the rack rotation and the electrical behavior of the rectifier output into a unified collaborative control system, thereby realizing intelligent adaptive adjustment of the electroplating process.

[0023] In this embodiment, the physical parameter signal characterizing the contact state between the rack and the conductive base is determined to be the dynamic contact resistance value between the rack and the conductive base. The dynamic contact resistance value is a key physical quantity for measuring the quality of contact between two conductors. During the electroplating process, the contact between the rack and the conductive base is not ideal; factors such as oxide film, dirt, and uneven contact pressure may exist, causing the contact resistance to change dynamically as the rack rotates. Using the dynamic contact resistance value as a physical parameter signal characterizing the contact state can directly reflect the conductivity of the contact interface. The smaller the value, the tighter the contact and the stronger the conductivity; conversely, the larger the value, the weaker the contact and the poorer the conductivity.

[0024] Reference Figure 2As shown, to synchronously acquire physical parameter signals characterizing the contact state between the hanger and the conductive base, this application employs the following method: a voltage sampling terminal is set on the rotation axis of the hanger, and a current sampling terminal is set on the conductive base. Real-time voltage drop and real-time conduction current between the hanger and the conductive base are synchronously acquired at a preset sampling frequency, and the dynamic contact resistance value is calculated. The rotation axis of the hanger is the hub connecting the hanger to the external power supply. Setting a voltage sampling terminal here allows for effective measurement of the potential difference between the hanger and the conductive base. The voltage sampling terminal can be implemented using non-contact or contact slip ring brushes, ensuring stable voltage signal acquisition during hanger rotation. The conductive base is the input terminal for the electroplating current. Setting a current sampling terminal here, such as a Hall sensor or shunt, allows for accurate measurement of the actual current flowing through the conductive base and into the hanger. This layout ensures the accuracy of voltage and current measurements, providing reliable raw data for calculating the dynamic contact resistance. The dynamic contact resistance value can be obtained using Ohm's law (R=U / I). To capture the dynamic changes during the rack's rotation, voltage drop and conduction current need to be synchronously acquired at a preset sampling frequency. This sampling frequency should be high enough to ensure that the subtle changes in contact resistance during one rotation of the rack are fully captured; for example, it can be determined based on the rack's rotation speed and the required phase resolution. The dynamic contact resistance value at the current moment can be calculated by dividing the synchronously acquired real-time voltage drop by the real-time conduction current.

[0025] Reference Figure 3 As shown, after using the dynamic contact resistance value as a physical parameter signal of the contact state between the rack and the conductive base, this application further proposes a specific method for calculating the real-time conductivity assessment value corresponding to each phase point within the current rotation cycle based on the contact state change characteristics. This method includes: during the continuous rotation of the electroplating rack, a complete rotation cycle is first used as the calculation window. This means that the data acquisition and processing range is limited to the time period within which the rack completes one 360-degree rotation. Within this calculation window, the system continuously extracts the dynamic contact resistance values ​​corresponding to each sampling moment. These dynamic contact resistance values ​​are calculated based on the real-time voltage drop and real-time conduction current between the rack and the conductive base, reflecting the instantaneous contact state of the rack at different rotation phases. By correlating these resistance values ​​with the corresponding rotation phase angle, a resistance-phase sequence of contact resistance changing with the phase angle is formed. This sequence intuitively demonstrates the periodic change law of the contact resistance of the rack throughout the entire rotation cycle.

[0026] Based on this, in order to effectively evaluate and compare these dynamic contact resistance values, it is necessary to accurately determine the cycle time of one rotation of the hanger according to its rotation speed. This can be achieved by monitoring the rotation speed in real time using sensors or encoders on the hanger's rotating shaft, and calculating the precise time required to complete one full rotation. For example, if the hanger rotates at a constant speed, the cycle time is 60 seconds divided by the number of revolutions per minute.

[0027] Subsequently, the arithmetic mean of all dynamic contact resistance values ​​collected within that cycle is used as the reference resistance value for that cycle. This reference resistance value represents the overall average level of contact resistance between the fixture and the conductive base within the current rotation cycle. By dividing the dynamic contact resistance value at each sampling moment by this reference resistance value, a normalized resistance ratio can be obtained. This normalization process eliminates potential overall resistance differences between different cycles or different fixtures, making the resistance values ​​at different phase points comparable and reflecting their relative level to the average level of that cycle.

[0028] To more intuitively reflect conductivity, the reciprocal of the normalized resistance ratio obtained above is taken to obtain the normalized contact conductivity value. Conductivity is the reciprocal of resistance; a larger value indicates stronger conductivity, which better aligns with people's intuitive understanding of conductivity.

[0029] Ultimately, the normalized contact conductivity value at each phase point is defined as the real-time conductivity assessment value. A higher normalized contact conductivity value clearly indicates stronger conductivity at that phase point.

[0030] After calculating the real-time conductivity assessment value, it needs to be compared with a preset conductivity benchmark value to achieve adaptive adjustment of the rectifier output power. In practical applications, accurately and reliably determining this preset conductivity benchmark value to ensure precise judgment of the contact state between the hanger and the conductive base is key to achieving efficient adaptive adjustment. An improperly set benchmark value may lead to misjudgment of the contact state, thus affecting electroplating quality and efficiency.

[0031] Reference Figure 4 As shown, this application further proposes that the preset conductivity benchmark value be predetermined in the following manner: First, the rack is rotated at the same speed as during actual electroplating, under no-load conditions without any workpiece loaded, and the dynamic contact resistance values ​​at each phase point are collected within one complete rotation cycle. Rotating the rack under no-load conditions without any workpiece loaded, when pre-determining the conductivity benchmark value, aims to eliminate the influence of the workpiece itself on the contact state between the rack and the conductive base, thereby obtaining optimal contact conductivity performance data determined purely by the rack structure and conductive base design. Rotating at the same speed as during actual electroplating ensures that the collected dynamic contact resistance values ​​accurately reflect the mechanical contact characteristics of the rack at the actual operating speed, avoiding data distortion caused by speed differences. By setting voltage sampling terminals on the rack's rotation axis and current sampling terminals on the conductive base, the real-time voltage drop and real-time conduction current between the rack and the conductive base can be simultaneously collected, and the dynamic contact resistance value at each phase point can then be calculated.

[0032] Secondly, the reciprocal of the dynamic contact resistance value at each phase point is taken to obtain the instantaneous contact conductance value at each phase point. The contact resistance value directly reflects the degree of obstruction to current passing through the contact interface, while its reciprocal, the contact conductance value, more intuitively characterizes the ease with which current passes through the contact interface or its conductivity. By taking the reciprocal of the dynamic contact resistance value collected at each phase point, the instantaneous contact conductance value of that phase point under no-load conditions can be obtained, which provides a more physically meaningful conductivity index for subsequent evaluation and normalization processing.

[0033] Next, the arithmetic mean of the instantaneous contact conductance values ​​at each phase point is used as the baseline mean. Then, the instantaneous contact conductance value at each phase point is divided by the baseline mean to obtain the no-load normalized contact conductance value for each phase point. To eliminate potential absolute numerical differences between different fixtures or under different testing environments, and to highlight the fluctuation characteristics of relative conductivity between phase points, this application employs normalization processing. The arithmetic mean of the instantaneous contact conductance values ​​at all phase points within a complete rotation cycle is used as the baseline mean for that cycle. Then, the instantaneous contact conductance value at each phase point is divided by this baseline mean to obtain the no-load normalized contact conductance value. This normalization processing makes the conductivity data of different fixtures or different batches of fixtures comparable and more clearly reveals the relative strength of conductivity at each phase point during the rotation of the fixture.

[0034] Finally, the no-load normalized contact conductivity value of each phase point is used as the preset conductivity benchmark value for that phase point. Ultimately, the no-load normalized contact conductivity value calculated above for each phase point is directly used as the preset conductivity benchmark value for that phase point. This benchmark value represents the optimal relative conductivity that the fixture can achieve at each specific rotational phase point under ideal no-load conditions. During the actual electroplating process, the real-time collected conductivity assessment value will be compared with these preset benchmark values ​​to accurately determine whether the contact state of the current phase point is in a weak or tight range, providing a reliable basis for subsequent power adjustment.

[0035] Reference Figure 5 As shown, this application further proposes a specific method for comparing the real-time conductivity assessment value with a preset conductivity benchmark value, including: comparing the real-time conductivity assessment value at the current sampling time with the no-load normalized contact conductivity value corresponding to the phase angle at the current sampling time, wherein the real-time conductivity assessment value is the normalized contact conductivity value; if the real-time conductivity assessment value at the current sampling time is less than the no-load normalized contact conductivity value corresponding to the phase angle, it is determined that the current contact is in a weak contact range, and a first power regulation command for reducing the rectifier output current is generated; if the real-time conductivity assessment value at the current sampling time is greater than or equal to the no-load normalized contact conductivity value corresponding to the phase angle, it is determined that the current contact is in a tight contact range, and a second power regulation command for increasing the rectifier output current is generated.

[0036] The step of comparing the real-time conductivity assessment value at the current sampling moment with the no-load normalized contact conductivity value corresponding to the phase angle at the current sampling moment aims to achieve a refined, phase angle-dependent conductivity assessment. During the rotation of the electroplating rack, the contact state between the rack and the conductive base changes dynamically, and the contact quality may differ significantly at different phase angles. Using only a global, phase-insensitive conductivity benchmark value for comparison may not accurately reflect the actual conductivity at a specific phase point. By comparing the real-time conductivity assessment value at the current sampling moment with the no-load normalized contact conductivity value corresponding to the specific phase angle of the rack at that moment, accurate determination of the conductivity at each phase point can be achieved. Specifically, after acquiring the rotation phase signal at the current sampling moment, the system retrieves the no-load normalized contact conductivity value corresponding to that phase angle based on a pre-established correspondence between phase angles and no-load normalized contact conductivity values ​​(e.g., stored in a lookup table or function). Subsequently, the real-time calculated normalized contact conductivity value is numerically compared with the retrieved no-load normalized contact conductivity value. This comparison can be a direct comparison of numerical values, or a comparison based on a certain tolerance range.

[0037] If the real-time conductivity assessment value at the current sampling moment is less than the no-load normalized contact conductivity value corresponding to the phase angle, it is determined that the current contact is in a weak range. The logic for generating a first power adjustment command to reduce the rectifier output current is crucial for adaptive power regulation. When the real-time conductivity assessment value (i.e., the conductivity under actual load) is lower than the ideal conductivity under no-load conditions (represented by the no-load normalized contact conductivity value), it indicates that the contact state at the current phase point is poor, posing a risk of weak contact. In this case, maintaining the original power output may lead to localized overheating, ablation, or a decrease in plating quality. Therefore, generating a command to reduce the rectifier output current aims to protect the fixture and workpiece, avoiding negative impacts caused by poor contact. Specifically, when the comparison result is "less than," the system triggers a preset logic branch, generating a first power adjustment command. This command can be a simple signal instructing the rectifier to execute a preset current reduction strategy (e.g., reducing to a fixed percentage, or dynamically adjusting based on the difference), or a command containing a specific target current value.

[0038] If the real-time conductivity assessment value at the current sampling moment is greater than or equal to the no-load normalized contact conductivity value corresponding to the phase angle, then it is determined that the current contact is in the tight contact range, and a second power regulation command to increase the rectifier output current is generated. This judgment logic is the opposite of the above situation. When the real-time conductivity assessment value reaches or exceeds the ideal conductivity under no-load conditions, it indicates that the contact state at the current phase point is good and the conductivity is sufficient. In this case, the output current of the rectifier can be appropriately increased to make full use of the good conductivity conditions, improve electroplating efficiency, or improve electroplating quality. This reflects the "increase" capability of adaptive regulation, rather than just "decrease" protection. Specifically, when the comparison result is "greater than or equal to", the system will trigger another preset logic branch to generate a second power regulation command. This command can instruct the rectifier to execute a preset current increase strategy (e.g., increase to a certain fixed ratio, or dynamically adjust according to the difference), or it can be a command containing a specific target current value.

[0039] Based on the above comparison results, referring to Figure 6 As shown, this application further proposes a specific method for generating a first power regulation command to reduce the rectifier output current, which includes: when the real-time conductivity assessment value is less than the no-load normalized contact conductance value corresponding to the phase angle, but greater than or equal to 90% of the no-load normalized contact conductance value corresponding to the phase angle, generating a first power regulation command to reduce the current output current value of the rectifier to 95% of the current output current value; when the real-time conductivity assessment value is less than 90% of the no-load normalized contact conductance value corresponding to the phase angle, generating a first power regulation command to reduce the current output current value of the rectifier to 85% of the current output current value.

[0040] To address weak contact issues more precisely, this application further subdivides the weak contact range into different degrees. The first case is where the real-time conductivity assessment value is less than the no-load normalized contact conductivity value corresponding to the phase angle, but still greater than or equal to 90% of it. This indicates a slight decrease in contact condition, classifying it as mild weakness. The second case is where the real-time conductivity assessment value is less than 90% of the no-load normalized contact conductivity value corresponding to the phase angle, indicating a more significant decrease in contact condition, classifying it as severe weakness. This tiered judgment mechanism allows the system to identify contact problems of different degrees. For different degrees of weak contact, the system generates different first power adjustment commands. For mild weakness, the command requires reducing the rectifier's current output current value to 95% of its current output current value. This moderate reduction aims to avoid excessive intervention while ensuring plating quality. For severe weakness, the command requires reducing the rectifier's current output current value to 85% of its current output current value. This more significant reduction is to effectively avoid excessively high local current density caused by poor contact, thereby preventing workpiece scorching or a decline in plating quality.

[0041] Based on the above comparison results, referring to Figure 7 As shown, this application further proposes generating a second power regulation command for increasing the rectifier output current, specifically including: when the real-time conductivity assessment value is greater than or equal to the no-load normalized contact conductance value corresponding to the phase angle, calculating the ratio of the real-time conductivity assessment value to the no-load normalized contact conductance value to obtain the contact conductance margin ratio; and determining the target output current value of the rectifier according to the contact conductance margin ratio in the following manner: I t =I c ·(1+α·(R c -1)); where I t For the target output current value, I c R is the current output current value. c The contact conductivity margin is α, which is a preset current compensation coefficient with a value range of 0.3 to 0.7. The value of α is negatively correlated with the temperature of the current electroplating solution. A second power regulation command is generated to increase the output current of the rectifier to the target output current value.

[0042] When the real-time conductivity assessment value is not lower than the no-load normalized contact conductivity value, it indicates that the current contact between the hanger and the conductive base is good and the conductivity is sufficient. At this point, by calculating the ratio between the real-time conductivity assessment value and the no-load normalized contact conductivity value, the degree of surplus conductivity relative to the benchmark can be quantified, thus obtaining the contact conductivity surplus ratio R. c The ratio R c A value greater than or equal to 1 is a quantitative indicator that directly reflects the current degree of contact.

[0043] Formula I above t =I c ·(1+α·(R c -1)) is used based on the quantified contact conductivity surplus ratio R c The target output current value I that the rectifier should be adjusted to is dynamically calculated. t Among them, I c This represents the actual output current value of the rectifier at the current moment. R c -1 indicates the relative amount by which the current conductivity exceeds the baseline. The preset current compensation coefficient α is a key adjustment parameter that determines the sensitivity or aggressiveness of the current increase. The value of α is set between 0.3 and 0.7, allowing the system to be flexibly configured according to the actual electroplating process requirements to balance electroplating efficiency and coating quality. For example, a larger α value results in a more significant current increase; a smaller α value results in a more conservative current increase. Furthermore, the value of α is negatively correlated with the temperature of the current electroplating solution. This means that when the temperature of the electroplating solution increases, the value of α should be appropriately reduced, and vice versa. This is because an increase in the temperature of the electroplating solution usually leads to increased conductivity. If a high current compensation coefficient is still used at this time, it may lead to excessive current, causing problems such as scorching or roughness of the coating. Through this negative correlation, the system can further refine the current compensation strategy to ensure stable electroplating results under different temperature conditions. After accurately calculating the target output current value I... t The system will then generate a specific second power regulation command. This command includes the target current value I. t The command is then sent to the rectifier control unit. Upon receiving the command, the rectifier control unit adjusts its output accordingly, changing the current value from the current I... c Upgraded to I t This process is real-time, ensuring that the rectifier's output power closely follows the periodic contact state changes of the hanger's rotation phase, thereby achieving adaptive power adjustment.

[0044] During the continuous rotation of the electroplating rack, although the rotation phase signal of the rack can be acquired in real time and the physical parameter signals characterizing the contact state between the rack and the conductive base can be collected simultaneously, and power adjustment commands can be generated based on these signals to adjust the output current value of the rectifier in real time, this instantaneous response adjustment method may lead to frequent current fluctuations, making it difficult to achieve a stable and efficient electroplating process. Especially when the periodic contact state changes of the rack rotation are complex, it may not be able to fully utilize historical data and periodic patterns to optimize the current output.

[0045] Reference Figure 8As shown, this application proposes a method for real-time adjustment of the rectifier's output current value, so that the rectifier's output power changes with the periodic contact state of the rack's rotation phase. Specifically, it includes: pre-establishing a correspondence table between each phase point of the rack and the rectifier's output current value within a complete rotation cycle. Each phase angle in the table corresponds to a preset output current value. This means that before the electroplating process begins, the system constructs a mapping relationship storing the current values ​​that the rack should output at different rotation phase angles based on empirical data, historical operation records, or through a calibration run. This correspondence table can be a lookup table, an array, or a function, where each entry associates a specific rotation phase angle (e.g., 0 to 360 degrees, or a discrete phase range) with a corresponding preset output current value. These preset values ​​represent the initial or reference current that the rectifier should provide at that phase point, considering the expected contact state between the rack and the conductive base.

[0046] Once the rotation phase angle at the current sampling moment is obtained, the system queries the corresponding table for a preset output current value that matches the rotation phase angle. The rectifier's current output current value is then adjusted to this preset value. This means that during the actual rotation of the fixture, the control system continuously monitors the fixture's rotation phase signal. Once the current rotation phase angle is obtained, the system immediately searches the pre-established table for the preset output current value that best matches that phase angle. Subsequently, the control system sends a command to the rectifier to adjust its output current value to the found preset value. This mechanism ensures that current adjustment is no longer merely a passive response based on instantaneous contact states, but incorporates the prediction of periodic changes, thus achieving smoother and more proactive current control.

[0047] Each time the hanger completes a full rotation cycle, the preset output current values ​​corresponding to each phase angle in the correspondence table are updated based on the contact state change characteristics collected in the current cycle. This improves the matching degree between the output current and the contact state change characteristics in the next cycle. Specifically, after the hanger completes a full rotation cycle, the system reviews and analyzes all contact state change characteristics collected during that cycle (e.g., real-time conductivity assessment values, dynamic contact resistance values, etc.). Based on this actually collected data, the system evaluates the matching degree between the preset output current values ​​in the current correspondence table and the actual contact state. If the preset current value for a certain phase point fails to effectively address the actual contact condition at that phase point (e.g., weak contact but current not adjusted in time), the system will correct and update the preset output current value for that phase point in the correspondence table. This update process can employ various algorithms, such as iterative optimization based on error feedback and adaptive control algorithms, aiming to ensure that the updated preset current value more accurately matches the actual contact state of the hanger in the next rotation cycle, thereby achieving continuous adaptive optimization.

[0048] In this embodiment, during the process of adjusting the output current, the thickness of the deposited metal layer is continuously monitored, and when the thickness of the deposited metal layer reaches the preset target thickness, a control signal to stop electroplating is output.

[0049] Specifically, continuous monitoring of the deposited metal layer thickness refers to acquiring the actual thickness information of the metal layer on the workpiece surface in real time during the electroplating process using various sensors or calculation methods. For example, non-contact measuring devices such as online eddy current sensors, ultrasonic sensors, or X-ray fluorescence spectrometers can be used to scan and measure the workpiece surface within the electroplating tank or as the workpiece passes through a specific detection area. These sensors can output electrical signals or spectral data related to the metal layer thickness in real time. Another approach is based on Faraday's law of electrolysis. By accurately measuring and accumulating the total amount of electricity flowing through the electroplating tank, combined with the current efficiency of the electroplating solution, the electrochemical equivalent of the metal, and the effective plating area of ​​the workpiece, the average thickness of the deposited metal can be estimated. Alternatively, the workpiece can be periodically weighed, and the deposition thickness can be calculated based on the weight gain, but this is typically used as a calibration method for offline detection or online methods. Regardless of the method used, the monitoring system needs sufficient accuracy and response speed to ensure the real-time nature and accuracy of the thickness data.

[0050] The preset target thickness refers to the ideal thickness value that the electroplated layer should achieve, as set in advance according to product design requirements and process specifications. This value is usually entered by the operator or loaded from the process database during the electroplating process parameter configuration stage, and it represents the minimum or optimal metal layer thickness required for the product's function, performance, or appearance.

[0051] When the deposited metal layer reaches the preset target thickness, the system outputs a control signal to stop electroplating. This control signal can be an electrical signal, a network command, or a mechanical command, used to trigger the termination action of the electroplating equipment. For example, the signal can be sent directly to the electroplating rectifier to immediately cut off the output current, thereby stopping metal deposition; or the signal can control a robotic arm or lifting device to lift the electroplating rack out of the electroplating solution; or the signal can control the electroplating solution circulation pump to stop working or open the drain valve to terminate the electroplating reaction. In this way, it is ensured that the electroplating process can be stopped quickly and accurately when the target thickness is reached.

[0052] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for adaptive adjustment of electroplating conductivity power based on the rotation of electroplating racks, characterized in that, Includes the following steps: During the continuous rotation of the electroplating rack, the rotation phase signal of the rack is acquired in real time, and physical parameter signals characterizing the contact state between the rack and the conductive base are collected simultaneously. Based on the rotation phase signal and physical parameter signal, the contact state change characteristics associated with the rotation phase are extracted, and based on the contact state change characteristics, the real-time conductivity assessment value corresponding to each phase point in the current rotation cycle is calculated. The real-time conductivity assessment value is compared with the preset conductivity benchmark value; If the real-time conductivity assessment value is lower than the conductivity benchmark value, the current phase is determined to be in the weak contact range, and a first power regulation command is generated to reduce the rectifier output current. If the real-time conductivity assessment value is not lower than the conductivity benchmark value, then the current phase is determined to be in the close contact range, and a second power regulation command is generated to increase the rectifier output current. According to the first power adjustment command or the second power adjustment command, the output current value of the rectifier is adjusted in real time so that the output power of the rectifier changes with the periodic contact state change of the rotation phase of the hanger.

2. The adaptive adjustment method for electroplating conductivity power based on electroplating fixture rotation according to claim 1, characterized in that: The physical parameter signal characterizing the contact state between the hanger and the conductive base is the dynamic contact resistance value between the hanger and the conductive base; the specific method for synchronously acquiring the physical parameter signal characterizing the contact state between the hanger and the conductive base is as follows: A voltage sampling terminal is set on the rotating shaft of the hanger, and a current sampling terminal is set on the conductive base. The real-time voltage drop and real-time conduction current between the hanger and the conductive base are collected synchronously at a preset sampling frequency, and the dynamic contact resistance value is calculated.

3. The adaptive adjustment method for electroplating conductivity power based on electroplating fixture rotation according to claim 2, characterized in that: Based on the characteristics of contact state changes, the real-time conductivity assessment value corresponding to each phase point within the current rotation cycle is calculated, specifically including: Using a complete rotation cycle as the calculation window, the dynamic contact resistance value corresponding to each sampling moment within the rotation cycle is extracted to form a resistance-phase sequence of contact resistance as a function of phase angle. Determine the cycle time of one rotation of the hanger based on its rotation speed; The arithmetic mean of all dynamic contact resistance values ​​collected within the period is used as the reference resistance value of the period. The dynamic contact resistance value at each sampling moment is divided by the reference resistance value to obtain the normalized resistance ratio. Taking the reciprocal of the normalized resistance ratio yields the normalized contact conductivity. The real-time conductivity assessment value is the normalized contact conductivity value of each phase point. The larger the normalized contact conductivity value, the stronger the conductivity of the phase point.

4. The adaptive adjustment method for electroplating conductivity power based on electroplating fixture rotation according to claim 3, characterized in that: The preset conductivity benchmark value is determined in advance in the following manner: The fixture is rotated at the same speed as during actual electroplating under no-load conditions without any electroplated workpieces loaded, and the dynamic contact resistance values ​​of each phase point are collected within a complete rotation cycle. The instantaneous contact conductance at each phase point is obtained by taking the reciprocal of the dynamic contact resistance value at each phase point. The arithmetic mean of the instantaneous contact conductance values ​​at each phase point is used as the baseline mean. The instantaneous contact conductance values ​​at each phase point are then divided by the baseline mean to obtain the no-load normalized contact conductance values ​​at each phase point. The no-load normalized contact conductivity value of each phase point is used as the preset conductivity benchmark value of the phase point.

5. The adaptive adjustment method for electroplating conductivity power based on electroplating fixture rotation according to claim 4, characterized in that: The real-time conductivity assessment value is compared with the preset conductivity benchmark value, specifically: The real-time conductivity assessment value at the current sampling time is compared with the no-load normalized contact conductivity value corresponding to the phase angle at the current sampling time. The real-time conductivity assessment value is the normalized contact conductivity value. If the real-time conductivity assessment value at the current sampling time is less than the no-load normalized contact conductivity value corresponding to the phase angle, it is determined that the current contact is in a weak range, and a first power regulation command is generated to reduce the rectifier output current. If the real-time conductivity assessment value at the current sampling time is greater than or equal to the no-load normalized contact conductivity value corresponding to the phase angle, it is determined that the current contact is in the tight contact range, and a second power regulation command for increasing the rectifier output current is generated.

6. The adaptive adjustment method for electroplating conductivity power based on electroplating fixture rotation according to claim 5, characterized in that: Generate a first power regulation command to reduce the rectifier output current, specifically including: When the real-time conductivity assessment value is less than the no-load normalized contact conductance value corresponding to the phase angle, but greater than or equal to 90% of the no-load normalized contact conductance value corresponding to the phase angle, a first power regulation command is generated to reduce the current output current value of the rectifier to 95% of the current output current value. When the real-time conductivity assessment value is less than 90% of the no-load normalized contact conductivity value corresponding to the phase angle, a first power regulation command is generated to reduce the current output current value of the rectifier to 85% of the current output current value.

7. The adaptive adjustment method for electroplating conductivity power based on electroplating fixture rotation according to claim 5, characterized in that: Generate a second power regulation command to increase the rectifier output current, specifically including: When the real-time conductivity assessment value is greater than or equal to the no-load normalized contact conductivity value corresponding to the phase angle, the ratio of the real-time conductivity assessment value to the no-load normalized contact conductivity value is calculated to obtain the contact conductivity margin ratio. Based on the contact conductivity margin, the target output current value of the rectifier is determined as follows: I t =I c ·(1+α·(R c -1)); Among them, I t For the target output current value, I c R is the current output current value. c The contact conductivity margin is α, which is a preset current compensation coefficient with a value range of 0.3 to 0.

7. The value of α is negatively correlated with the temperature of the current electroplating solution. Generate a second power regulation command to increase the rectifier's output current to the target output current value.

8. The adaptive adjustment method for electroplating conductivity power based on the rotation of the electroplating fixture according to claim 1, characterized in that: The rectifier's output current value is adjusted in real time so that the rectifier's output power changes in accordance with the periodic contact state changes of the fixture's rotation phase. Specifically, this includes: A table is pre-established to correspond to each phase point of the fixture and the output current value of the rectifier within a complete rotation cycle. Each phase angle in the table corresponds to a preset output current value. Once the rotation phase angle at the current sampling moment is obtained, the preset output current value that matches the rotation phase angle is queried in the corresponding relationship table, and the current output current value of the rectifier is adjusted to the preset output current value. Each time the hanger completes a full cycle of rotation, the preset output current value corresponding to each phase angle in the corresponding relationship table is updated based on the contact state change characteristics collected in the current cycle, so as to improve the matching degree between the output current of the next cycle and the contact state change characteristics.

9. The adaptive adjustment method for electroplating conductivity power based on the rotation of the electroplating fixture according to claim 1, characterized in that: Also includes: During the adjustment of the output current, the thickness of the deposited metal layer is continuously monitored. When the thickness of the deposited metal layer reaches the preset target thickness, a control signal to stop electroplating is output.

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