Photovoltaic string welding machine and photovoltaic welding ribbon processing method

Abstract

The present invention discloses a photovoltaic string welding machine and a photovoltaic welding strip processing method, wherein the photovoltaic string welding machine comprises a first clamping component for pulling the welding strip from the welding strip reel, a second clamping component for cooperating with the first clamping component to stretch the welding strip, a cutting component for cutting the welding strip, and a first electrode and a second electrode for supplying power to the welding strip. The photovoltaic string welding machine provided by the present invention adds a first electrode and a second electrode to the photovoltaic string welding machine, and performs an annealing process on the cut welding strip, that is, before welding the battery cell, the welding strip is annealed. The current annealing time is short and the efficiency is high. It is also relatively simple to add an energizing measure before the welding strip is transported, and no other time cost and labor cost are incurred.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic welding tapes, and in particular to a photovoltaic string welding machine and a photovoltaic welding tape processing method. Background Art

[0002] At present, dense grid modules (represented by 9 grids) have gradually become the mainstream photovoltaic module products. Major companies have launched corresponding dense grid products, and many photovoltaic module manufacturers have the ability to mass produce. In the current material matching, dense grid modules basically use round wire welding ribbons as interconnecting strips. In the process of using automatic welding, part of the action of the stringer is pulling the welding ribbon-clamping the welding ribbon-stretching the welding ribbon-cutting the welding ribbon-carrying the welding ribbon. In this continuous process, the purpose of the stretching action of the welding ribbon is to make the welding ribbon pulled out from the reel change from a bent state to a state with a certain degree of straightness, which is convenient for the subsequent welding process.

[0003] The stretching process of the welding strip will increase the yield strength of the copper base material of the welding strip. The yield strength of the finished round wire welding strip is about 60-70n / m. After the welding strip is stretched, the yield strength can reach more than 100n / m, which is much greater than the standard upper limit of 90n / m. In the prior art, in order to reduce the yield strength of the welding strip, one method is to pass a large current through the copper wire processing link when the wire passes through the annealing wheel and other structures to complete the annealing treatment. This link is the treatment of the copper wire during the raw material processing; the other method is to pass current through the tin-coated copper strip when it passes through the electrified guide wheel in the welding strip processing, thereby completing the annealing treatment.

[0004] However, the method used in the prior art can only be used in the copper wire processing link and after the solder strip is coated with a tin layer, and the yield strength control accuracy of the solder strip after being stretched is poor.

[0005] Therefore, how to effectively improve the connection reliability of photovoltaic welding ribbons to the solar cells in photovoltaic modules and improve the product qualification rate is a technical problem that technical personnel in this field currently need to solve. Summary of the invention

[0006] The object of the present invention is to provide a photovoltaic string welding machine and a photovoltaic welding tape processing method, which are used to improve the connection reliability of the photovoltaic welding tape to the battery cells in the photovoltaic module.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A photovoltaic string welding machine comprises a first clamping component for pulling a welding ribbon from a welding ribbon reel, a second clamping component for cooperating with the first clamping component to stretch the welding ribbon, a cutting component for cutting the welding ribbon, and a first electrode and a second electrode for supplying power to the welding ribbon.

[0009] Preferably, it further comprises a fixing component for installing the cutting component and fixing the end of the welding strip, the second electrode is installed on the fixing component, and the first electrode is installed on the first clamping component.

[0010] Preferably, it also includes a monitoring component for obtaining real-time parameters of the welding strip, and a controller for controlling the magnitude of the annealing current input into the welding strip according to the information obtained by the monitoring component, and the first electrode, the second electrode, the controller and the monitoring component are all connected in an annealing circuit.

[0011] Preferably, it also includes a transformer for adjusting voltage and a rectifier for converting AC current into DC current, wherein the transformer is electrically connected to the welding strip, and the transformer is communicatively connected to the controller.

[0012] Preferably, the first clamping component is a clamping cylinder, and the second clamping component is a clamp.

[0013] A photovoltaic welding ribbon processing method comprises the following steps:

[0014] Step S1: Obtain a solder ribbon reel and pull the solder ribbon;

[0015] Step S2: After stretching the welding ribbon, cutting it;

[0016] Step S3: annealing the cut solder strip.

[0017] Preferably, after step S3, the method further includes:

[0018] Step S4: transporting the annealed soldering ribbon for use in soldering solar cells in photovoltaic modules.

[0019] Preferably, the step of passing the annealing current through the welding strip is as follows:

[0020] A string welding machine is used to pass a direct current through the welding strip.

[0021] or,

[0022] The annealing current is passed through the welding strip, specifically:

[0023] A rectifier is used to convert the annealing current from AC current to DC current;

[0024] A direct current is passed through the welding ribbon.

[0025] Preferably, step S3 comprises:

[0026] Fixing the two ends of the cut welding strip;

[0027] Connecting the two ends of the welding ribbon to an annealing circuit;

[0028] Power off after the preset power-on time;

[0029] The solder ribbon is cooled.

[0030] Preferably, the step S3 further comprises:

[0031] Obtaining the real-time current and / or real-time voltage, real-time temperature and power-on time of the welding strip after power is turned on;

[0032] The magnitude of the annealing current is adjusted according to the real-time current and / or real-time voltage, real-time temperature and power-on time.

[0033] Preferably, the step S3 further comprises:

[0034] When the real-time current is greater than the set current threshold, the annealing current is reduced;

[0035] When the real-time voltage is greater than a set voltage threshold, the annealing current is reduced;

[0036] When the real-time temperature is greater than a set temperature threshold, the annealing current is reduced.

[0037] The photovoltaic string welding machine provided by the present invention comprises a first clamping component for pulling the welding ribbon from the welding ribbon reel, a second clamping component for cooperating with the first clamping component to stretch the welding ribbon, a cutting component for cutting the welding ribbon, and a first electrode and a second electrode for supplying power to the welding ribbon. The photovoltaic string welding machine provided by the present invention adds a first electrode and a second electrode to the photovoltaic string welding machine, and performs an annealing process on the cut welding ribbon, that is, before welding the battery cell, the welding ribbon is annealed. The current annealing time is short and the efficiency is high. It is also relatively simple to add an energizing measure before the welding ribbon is transported, and no other time cost and labor cost are incurred.

[0038] The photovoltaic welding tape processing method provided by the present invention comprises the following steps: step S1: obtaining a welding tape reel and pulling the welding tape; step S2: cutting the welding tape after stretching; step S3: annealing the cut welding tape. The photovoltaic welding tape processing method provided by the present invention anneals the welding tape after pulling, stretching and cutting the welding tape. The method can more accurately set the annealing process parameters of the welding tape, and can more fully consider the effect of stretching on the yield strength of the welding tape, thereby further improving the effectiveness of the annealing process, improving the firmness of the connection between the welding tape and the battery cell, and reducing the defective rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 A schematic structural diagram of a specific implementation of the photovoltaic string welding machine provided by the present invention;

[0041] Figure 2 This is a schematic diagram of the structure of the annealing circuit in the photovoltaic string welding machine provided by the present invention;

[0042] Figure 3 A flow chart of the photovoltaic ribbon processing method provided by the present invention;

[0043] Among them: the first clamping component-1; the second clamping component-2; the welding strip-3; the transformer-4; the controller-5; the monitoring component-6; the welding strip reel-7; the guide wheel-8; the cutting component-9; the second electrode-10; the first electrode-11; the battery cell-12; the fixing component-13. DETAILED DESCRIPTION

[0044] The core of the present invention is to provide a photovoltaic string welding machine and a photovoltaic welding tape processing method, which are used to improve the connection reliability of the photovoltaic welding tape to the battery cells in the photovoltaic module.

[0045] In order to enable those skilled in the art to better understand the solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0046] Please refer to Figures 1 to 3 , Figure 1 A schematic structural diagram of a specific implementation of the photovoltaic string welding machine provided by the present invention; Figure 2 This is a schematic diagram of the structure of the annealing circuit in the photovoltaic string welding machine provided by the present invention; Figure 3 The present invention provides a flow chart of the photovoltaic ribbon processing method.

[0047] In this embodiment, the photovoltaic string welding machine includes a first clamping component 1 , a second clamping component, a cutting component 9 , a first electrode 11 , and a second electrode 10 .

[0048] Among them, the first clamping component 1 is used to pull the welding ribbon 3 from the welding ribbon reel 7, the second clamping component 2 is used to cooperate with the first clamping component 1 to stretch the welding ribbon 3, the cutting component 9 is used to cut the welding ribbon 3, the first electrode 11 and the second electrode 10 are used to supply power to the welding ribbon 3, complete the power-on circuit, so as to realize the heating of the welding ribbon 3, and then complete the annealing process of the welding ribbon 3.

[0049] The photovoltaic string welding machine provided by the present invention adds a first electrode 11 and a second electrode 10 to the photovoltaic string welding machine, and anneals the cut welding strip 3, that is, before welding the battery cell 12, the welding strip 3 is annealed. The current annealing time is short and the efficiency is high. It is also relatively simple to add a power-on measure before transporting the welding strip 3, and no other time cost and labor cost will be incurred.

[0050] Furthermore, the photovoltaic string welding machine also includes a fixing component 13 for installing the cutting component 9 and fixing the end of the welding strip 3. Before the cutting component 9 cuts the welding strip 3, the end of the welding strip 3 is pulled by the first clamping component 1. When the welding strip 3 needs to be stretched, the second clamping component 2 is actuated, and the welding strip 3 is stretched between the first clamping component 1 and the second clamping component 2. After the stretching is completed, the cutting component 9 cuts the welding strip 3. After the cut welding strip 3, one end is fixed by the fixing component 13, and the other end is still clamped by the first clamping component 1.

[0051] Furthermore, the second electrode 10 is mounted on the fixing component 13 , and the first electrode 11 is mounted on the first clamping component 1 . The first electrode 11 and the second electrode 10 are respectively located at two ends of the cut solder strip 3 .

[0052] On the basis of the above embodiments, a guide wheel 8 is further included, and the guide wheel 8 can change the extension direction of the welding strip 3 to facilitate the subsequent stretching and cutting operations.

[0053] On the basis of the above-mentioned embodiments, a controller 5 and a monitoring component 6 are also included. Among them, the solder strip 3 is regarded as a load in the annealing circuit, and heat is generated when it is powered on to complete the annealing; the monitoring component 6 is used to obtain the real-time parameters of the solder strip 3. Specifically, the monitoring component 6 monitors the real-time current and / or real-time voltage, real-time temperature and power-on time passing through the solder strip 3 in real time to prevent overheating or insufficient annealing due to excessive temperature; the controller 5 is used to control the magnitude of the annealing current input to the solder strip 3 according to the information obtained by the monitoring component 6. Specifically, it controls the magnitude of the annealing current by the real-time current and / or real-time voltage, real-time temperature and power-on time fed back by the monitoring component 6, and outputs the magnitude of the annealing current, thereby controlling the magnitude and shutoff of the annealing current; the first electrode 11, the second electrode 10, the controller 5 and the monitoring component 6 are all connected in the annealing circuit.

[0054] On the basis of the above embodiments, a transformer 4 for adjusting the voltage is further included. The transformer 4 is electrically connected to the welding strip 3 , and the transformer 4 is communicatively connected to the controller 5 .

[0055] Based on the above embodiments, a rectifier for converting AC current into DC current is further included. The rectifier converts AC current into DC current, and the DC current is more stable and can be controlled more accurately.

[0056] Specifically, the circuit can be powered by an external power supply, for example, the power grid provides AC current, which is converted into DC current through a rectifier, or the DC current is directly provided by a string welder, and the voltage is increased to a required fixed value through a transformer 4. The monitoring component 6 monitors the real-time current and / or real-time voltage, real-time temperature and power-on time of the welding strip 3 and feeds back to the controller 5. The controller 5 controls the shutdown and current size of the output part of the circuit according to the feedback information and the set power-on time, and after adjusting the input current to the required annealing current, the welding strip 3 is energized.

[0057] On the basis of the above embodiments, the first clamping component 11 is a clamping cylinder, and the second clamping component 2 is a clamp. Specifically, when pulling the welding strip, the clamping cylinder is loosened, and when stretching, cutting, annealing and transporting the welding strip, the clamping cylinder clamps the welding strip 3; the clamp can realize the stretching and transportation of the welding strip 3.

[0058] In addition to the above-mentioned photovoltaic string welding machine, the present invention also provides a photovoltaic welding ribbon processing method.

[0059] The photovoltaic welding ribbon processing method comprises the following steps:

[0060] Step S1: Obtain the soldering ribbon reel 7 and pull the soldering ribbon 3, which can be achieved by the first clamping component 1;

[0061] Step S2: After the welding strip 3 is stretched, cutting is performed, which can be achieved by a cutting component 9;

[0062] Step S3 : performing annealing treatment on the cut solder strip 3 , which can be achieved by connecting the first electrode 11 and the second electrode 10 .

[0063] Further, after step S3, the method further includes:

[0064] Step S4: transporting the annealed soldering ribbon 3 for soldering the solar cells 12 in the photovoltaic module.

[0065] On the basis of the above embodiments, an annealing current is applied to the welding strip 3, specifically:

[0066] A direct current is passed through the welding strip 3 using a string welding machine.

[0067] or,

[0068] The annealing current is applied to the welding strip 3, specifically:

[0069] A rectifier is used to convert the annealing current from AC current to DC current;

[0070] A direct current is passed through the welding strip 3 .

[0071] Based on the above embodiments, step S3 includes:

[0072] Fixing the two ends of the cut welding ribbon 3 can be achieved by using a first clamping component 1 and a second clamping component 2;

[0073] Connect both ends of the welding strip 3 to the annealing circuit;

[0074] Power off after the preset power-on time;

[0075] The solder strip 3 is cooled, preferably at room temperature.

[0076] Based on the above embodiments, step S3 further includes:

[0077] Obtaining the real-time current and / or real-time voltage, real-time temperature and power-on time of the welding strip 3 after power-on;

[0078] The annealing current is adjusted according to the real-time current and / or real-time voltage, real-time temperature and power-on time. In the above steps, a feedback mechanism is added to effectively prevent overheating or insufficient annealing due to excessive temperature, thereby improving the product qualification rate.

[0079] Based on the above embodiments, step S3 further includes:

[0080] When the real-time current is greater than the set current threshold, the annealing current is reduced;

[0081] When the real-time voltage is greater than the set voltage threshold, the annealing current is reduced;

[0082] When the real-time temperature is greater than the set temperature threshold, the annealing current is reduced.

[0083] In a specific embodiment, since the photovoltaic welding strip 3 is composed of a copper substrate + a solder coating layer, the copper base layer is the main body, and during the traction and tensile cold deformation process, the internal stress of the copper material accumulates, the dislocation increases, and the yield strength and hardness increase. When a large current I≥80A is passed through the copper substrate, due to the thermal effect of the resistor, a large amount of heat is generated, causing the temperature of the copper material to rise rapidly to about 650°C, and fine grains grow inside the copper, eliminating deformation hardening, restoring the plasticity and deformation capacity of the copper substrate, and recrystallizing, so as to achieve the purpose of reducing the yield strength. Specifically, in the process of the welding strip 3 being transformed from the welding strip reel 7 into a weldable welding strip 3, it is processed section by section on the string welding machine, and the annealing process of the welding strip 3 is set after cutting the welding strip 3, and the welding strip 3 is energized by the first electrode 11 and the second electrode 10. Under the action of the large current, the annealing process of the welding strip 3 can be completed in a very short time, and the welding strip 3 is subsequently transported.

[0084] The photovoltaic welding tape processing method provided by the present invention solves the problem of increased yield strength of the welding tape 3 during the use stage by passing a large current through the welding tape 3. After the welding tape 3 is pulled, stretched, and cut, the welding tape 3 is annealed. This method can more accurately set the annealing process parameters of the welding tape 3, and can more fully consider the effect of stretching on the yield strength of the welding tape 3, thereby further improving the effectiveness of the annealing process, improving the firmness of the connection between the welding tape 3 and the battery cell 12, and reducing the defective rate.

[0085] The photovoltaic string welding machine and photovoltaic welding tape processing method provided by the present invention are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A photovoltaic string welding machine, characterized in that: The invention comprises a first clamping component (1) for pulling a soldering strip (3) from a soldering strip reel (7), a second clamping component (2) for cooperating with the first clamping component (1) to stretch the soldering strip (3), a cutting component (9) for cutting the soldering strip (3), and a first electrode (11) and a second electrode (10) for supplying power to the soldering strip (3); and also comprises a fixing component (13) for installing the cutting component (9) and fixing the end of the soldering strip (3), the second electrode (10) being installed on the fixing component (13), and the first electrode (11) being installed on the first clamping component (1).

2. The photovoltaic string welding machine according to claim 1, characterized in that: It also includes a monitoring component (6) for obtaining real-time parameters of the welding strip (3), and a controller (5) for controlling the magnitude of an annealing current input into the welding strip (3) according to information obtained by the monitoring component (6); the first electrode (11), the second electrode (10), the controller (5) and the monitoring component (6) are all connected in an annealing circuit.

3. The photovoltaic string welding machine according to claim 2, characterized in that: It also includes a transformer (4) for adjusting voltage and a rectifier for converting alternating current into direct current, wherein the transformer (4) is electrically connected to the welding strip (3), and the transformer (4) is communicatively connected to the controller (5).

4. The photovoltaic string welding machine according to any one of claims 1 to 3, characterized in that: The first clamping component (1) is a clamping cylinder, and the second clamping component (2) is a clamp.

5. A photovoltaic welding ribbon processing method, characterized in that: The following steps are involved: Step S1: obtaining a soldering ribbon reel (7) and pulling the soldering ribbon (3); Step S2: After stretching the welding strip (3), cutting it; Step S3: performing annealing treatment on the cut solder strip (3); After step S3, the method further includes: Step S4: transporting the annealed welding ribbon (3) for welding the battery cells (12) in the photovoltaic module; The step of passing an annealing current through the welding strip (3) is specifically as follows: Using a string welding machine to pass a direct current through the welding strip (3); or, The step of passing an annealing current through the welding strip (3) is specifically as follows: A rectifier is used to convert the annealing current from AC current to DC current; Passing a direct current through the welding strip (3); The step S3 comprises: Fixing the two ends of the cut welding strip (3); Connecting the two ends of the welding strip (3) to an annealing circuit; Power off after the preset power-on time; The solder strip (3) is cooled.

6. The photovoltaic ribbon processing method according to claim 5, characterized in that: The step S3 further comprises: Acquiring the real-time current and / or real-time voltage, real-time temperature and power-on time of the welding strip (3) after power is turned on; The magnitude of the annealing current is adjusted according to the real-time current and / or real-time voltage, real-time temperature and power-on time.

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