Excellence in Quality: Product Applications of Photovoltaic DC Power Supply SPD

Photovoltaic equipment is often exposed to outdoor environments over the long term, while the electronic components of inverters are highly sensitive to environmental conditions. Particularly on the DC side of photovoltaic systems, lightning conditions can be severe, often subjecting DC lines to overvoltage from lightning. To ensure durability, it is standard to install DC power supply SPD at critical points such as the outlet of the solar panels, combiner boxes, distribution cabinets, and inverters to limit lightning surge overvoltage.

Selection of DC Power Supply SPD in Photovoltaic Systems

In photovoltaic systems, the selection of DC side power surge protection devices must comply with IEC 61643-31 standards. Besides conventional parameters like voltage and current, attention should be paid to two key parameters:

UCPV (Maximum Continuous Operating Voltage)

In all protection modes (positive/negative, positive/ground, and negative/ground), Ucpv must be greater than or equal to the maximum open-circuit voltage Uoc max of the photovoltaic array under the worst conditions.

ISCPV (Rated Discharge Current)

The protector should be able to effectively handle the discharge current that may occur in the photovoltaic system.

Product Features of DC Power Supply SPD for Photovoltaic Systems

For the unique geographical environment and installation conditions of photovoltaic power stations, Techwin's DC power supply SPD have undergone rigorous testing and validation, and possess the following features:

High-quality materials and craftsmanship

Using PBT flame-retardant fireproof casing and built-in high-quality surge protection chips, they can withstand high-temperature environments up to 75°C.

High-performance protection

With high discharge capacity, low residual voltage, fast response, and no follow current, they are particularly suitable for DC side protection in solar power generation systems.

Modular design

Standard 35mm rail mounting, compact structure, easy installation, and maintenance.

Safety protection function

Built-in thermal trip device, visual alarm window indicates operating status, facilitating real-time monitoring and remote alarm control for users.

Installation Requirements for DC Power Supply SPD in Photovoltaic Systems

Depending on the layout and safety requirements of the photovoltaic system, the installation of DC power supply SPD needs to consider the following points:

For systems without external lightning protection devices (LPS) or systems that meet the safety spacing (s) requirements, SPD should be installed at key positions such as the output end of the solar modules, the combiner box, the distribution cabinet, and the inverter end.

When the distance between the photovoltaic modules and the inverter is greater than or equal to 10 meters, it is recommended to install two sets of SPD to provide adequate protection. If the distance is less than 10 meters, one set of SPD is sufficient to meet the protection requirements.

The total length of the connection cables (L1+L2) should be as short as possible, not exceeding 0.5 meters, to ensure compliance with relevant installation standards and electrical specifications.

Lightning protection design for photovoltaic power generation systems is crucial as it directly affects the long-term stable operation of the system and the lifespan of the equipment. As the solar market continues to expand, Techwin is committed to providing the most reliable DC power SPD solutions for photovoltaic systems, ensuring the security of customers’ investments and the continuous performance of the systems. For more information about our products and services, please feel free to contact our sales team.