PV Cell String Layout Machine: High Precision and High Efficiency

In photovoltaic module manufacturing, cell string layout is a critical process that directly determines module consistency and long-term reliability. Even minimal layout deviations may lead to power loss, hot spot risks, and other performance issues during lamination and field operation. With the accelerated adoption of high-efficiency cell technologies such as N-type TOPCon and HJT, solar cells are becoming larger in size, thinner in structure, and more sensitive to process variation. As a result, the industry is placing unprecedented demands on layout equipment in terms of precision, stability, and takt time. Photovoltaic cell string layout machines are therefore transitioning from traditional millimeter-level control to a new stage of micrometer-level precision manufacturing driven by machine vision and intelligent algorithms.

I. The “Four-Dimensional Working Principle” of Intelligent Layout Machines

Designed to achieve high precision and consistency, photovoltaic cell string layout machines operate through the coordinated interaction of four core systems: visual positioning, algorithm-based planning, mechanical execution, and closed-loop quality control. Taking advanced industry equipment as an example, the working principles are outlined below:

1. Visual Positioning System: Utilizing a 12-megapixel industrial camera, it captures the edges and busbar positions of solar cells at a rate of 0.01 seconds per frame. Combined with deep learning algorithms, it identifies defects such as microcracks and color variations, achieving positioning accuracy of ±0.05mm.

2. Smart Planning Engine: After inputting cell dimensions and electrical performance parameters, the system automatically generates the optimal layout plan. For example, for 210mm large-size cells, it dynamically adjusts inter-string spacing to 1.8mm, improving space utilization by 15% compared to traditional equipment.

3. Multi-axis Coordinated Execution: A six-axis robotic arm equipped with a vacuum suction cup grasps thin-film solar cells with 0.1mm step precision. Coupled with force feedback sensors, it dynamically adjusts gripping force in real time to prevent damage to ultra-thin cells (≤130μm thickness).

4. Quality Closed-Loop Control: Real-time monitoring of cell stacking height via laser displacement sensors, combined with PID algorithm-based automatic correction of glass substrate flatness errors, ensures a gap between the solar cell and substrate ≤0.02mm.

II. Industry Standard “Three-Tier Precision Control”

According to the 2025 industry white paper and mainstream module manufacturing requirements, photovoltaic cell string layout machines are generally classified into three precision levels to meet different cell technologies and production capacities:

1. Basic Level (±0.3mm): Suitable for standard PERC cell modules, achieved through mechanical positioning + pneumatic clamping. A company's equipment employs a dual-rail slider structure with repeat positioning accuracy of ±0.25mm, meeting the basic production capacity requirement of 60 cells per minute.

2. Advanced Class (±0.2mm): For N-type solar cells, vision servo control must be implemented. For example, a certain device achieves 1ms synchronization between the robotic arm and vision system via EtherCAT bus, maintaining dynamic accuracy of ±0.18mm even during high-speed motion.

3. Flagship Grade (±0.1mm): Used in ultra-thin modules such as heterojunction (HJT) cells, requiring laser interferometer calibration + nanometer-level servo drive. A company's FV5 series rotary servo drive employs a 23-bit multi-turn absolute encoder to achieve repeat positioning accuracy of ±0.08mm, overcoming an industry-wide technical bottleneck.

III. The Five-Step Implementation Method for Efficient Operations

To ensure both layout precision and production efficiency, intelligent cell string layout machines typically follow a standardized operational workflow:

1. Parameter Preset: Input cell dimensions (length × width × thickness), busbar count, and inter-series spacing into the HMI interface. The system automatically generates a 3D simulated layout diagram.

2. Incoming Inspection: EL testers screen out cells with microcracks or cold solder joints, preventing defective cells from entering the layout process.

3. First-Piece Verification: Manually place the first cell; the system automatically calibrates the robotic arm coordinate system to ensure zero deviation in subsequent layouts.

4. Batch Operation: After activating automatic mode, the equipment operates continuously at a cycle time of 5.5 seconds per string. Meanwhile, real-time production capacity and yield data are uploaded to the cloud through an industrial IoT interface.

5. Anomaly Handling: Upon detecting cell misalignment or robotic arm jamming, the system immediately triggers an alarm and pauses operation. Operators can remotely reset via a mobile app.

IV. Conclusion

As the photovoltaic industry continues to advance toward cost reduction, efficiency improvement, and quality enhancement, the evolution of cell string layout equipment is shifting from isolated precision improvements to fully integrated solutions combining vision systems, intelligent algorithms, motion control, and data connectivity. With the continued integration of artificial intelligence, precision servo technology, and digital manufacturing systems, photovoltaic layout machines will deliver higher consistency, improved stability, and superior yield performance—providing robust support for the large-scale production of high-efficiency modules.

ChinTiyan remains committed to the development of intelligent photovoltaic equipment. Driven by continuous technological innovation, the company provides high-precision and high-efficiency cell string layout solutions to photovoltaic manufacturers worldwide, supporting the high-quality development of the global renewable energy industry.