Structure and Production Process of Large-Scale Photovoltaic Inverters

Large-scale photovoltaic inverters consist of key components such as power modules, control units, input/output filters, cooling systems, and user interfaces. Their production involves component processing, assembly, and comprehensive testing, including performance, environmental adaptability, and safety tests. The assembly and testing production line integrates manual and automated operations, with automated conveyance, robotic assistance, and advanced testing equipment to ensure high efficiency, accuracy, and reliability. The entire process is strictly monitored to maintain product quality and meet industry standards.

The Structure of Large-Scale Photovoltaic Inverters

• Power Module: This is the core part of the inverter, responsible for converting direct current (DC) into alternating current (AC). It typically includes power semiconductor devices, such as IGBTs (Insulated Gate Bipolar Transistors) or other types of MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors).
• Control Unit: It manages the operation of the inverter, including the implementation of Maximum Power Point Tracking (MPPT) algorithms, as well as the start, stop, and protection functions of the inverter.
• Input/Output Filters: These are used to reduce electromagnetic interference (EMI) and ensure that the current waveform output by the inverter is smooth and meets grid requirements.
• Cooling System: Since inverters generate heat during operation, an effective cooling system is needed to maintain the normal working temperature of the inverter.
• User Interface: This provides an interface for users to operate and monitor the inverter, usually including a display screen and control buttons.

The Production Process of Photovoltaic Inverters

• Component Processing:
  • Circuit Board Manufacturing: Solder electronic components onto circuit boards to form control circuits and power conversion circuits. Ensure that solder joints are secure and free of cold soldering during the soldering process.
  • Heat Sink Processing: Process and treat heat sinks, such as surface treatment, drilling, etc., to enhance their cooling performance.
  • Enclosure Fabrication: Fabricate the enclosure of the photovoltaic inverter according to design requirements, including cutting, bending, welding, and other processes.
• Assembly:
  • Internal Assembly: Install the processed circuit boards, heat sinks, and other components inside the enclosure, and wire and connect them according to the design requirements.
  • External Interface Installation: Install external components such as input/output interfaces, display screens, and control buttons.
  • Preliminary Debugging: Conduct preliminary functional testing and debugging during the assembly process to ensure that all parts can work normally.
• Testing:
  • Performance Testing: Conduct comprehensive performance testing on photovoltaic inverters, including tests on conversion efficiency, output voltage stability, harmonic content, and other indicators.
  • Environmental Adaptability Testing: Simulate various harsh environmental conditions, such as high temperature, low temperature, and high humidity, to test the performance and reliability of photovoltaic inverters under these conditions.
  • Safety Testing: Conduct safety tests such as insulation resistance testing, leakage current testing, and ground resistance testing.

The Assembly and Testing Production Line of Photovoltaic Inverters

• Assembly Area:
  • Manual and Automated Combination: The assembly area typically includes multiple workstations, combining automated equipment for high-precision and repetitive operations (such as welding and screw tightening) with manual assembly stations for tasks that require flexibility.
  • Automated Conveyance: Use automated conveyance systems, such as power and free conveyors, to transport the components or assemblies between different workstations.
  • Robot Application: Utilize robots equipped with vision systems for automatic handling, transportation, and assembly operations to improve production efficiency and assembly accuracy.
• Testing Area:
  • Functional Testing: Conduct functional testing on the assembled inverters, including the stability of input and output voltage and current, as well as the efficiency and power curve of the inverter, to ensure that the product meets design specifications.
  • Safety Testing: Test the safety functions of the inverter, such as overload protection, short-circuit protection, and over-temperature protection.
  • Environmental Simulation Testing: Simulate environmental conditions that the inverter may encounter in actual use, such as temperature, humidity, and vibration, to ensure stable operation under various conditions.
  • Aging Testing: Conduct long-term operation tests to assess the durability and reliability of the product, identifying potential faults and defects in a timely manner.
  • Automated Testing Equipment: Equip with automated testing devices, such as automatic safety testing, forward voltage drop testing, grid-connected automatic testing, and aging automatic testing, to improve testing efficiency and accuracy.
• Packaging and Palletizing Area:
  • Automated Packaging: Use automated equipment for product packaging, such as automatic boxing, automatic wrapping, and automatic strapping.
  • Palletizing and Handling: Utilize robots or automated palletizing equipment to stack the packaged products, improving storage and logistics efficiency.
• Quality Control:
  • Full-Process Monitoring: Implement strict quality control throughout the assembly and testing process, with real-time monitoring and inspection at each step to ensure that each inverter meets the factory standards.
  • Error-Proofing Mechanism: In the assembly process, adopt error-proofing mechanisms and real-time monitoring systems to prevent assembly errors that could lead to rework and waste.