PV cable The characteristics of the, Cable material Its molecular structure will change, thus providing its various properties. Mechanical load resistance In fact, during installation and maintenance, the cable can be routed on the sharp edge of the roof structure, and the cable must withstand pressure, bending, tension, cross tensile load and strong impact. If the strength of the cable sheath is not enough, the cable insulation layer will be seriously damaged, which will affect the service life of the entire cable, or lead to short circuit, fire, personal injury and other problems.
The selection of photovoltaic power generation cables shall follow the general requirements of cable selection, that is, the selection shall be based on the voltage level, the allowable current for continuous operation, the short circuit thermal stability, the allowable voltage drop, the economic current density and the laying environmental conditions. At the same time, photovoltaic power generation has its own characteristics. Solar energy systems are often used in harsh environmental conditions, such as high temperature, cold and ultraviolet radiation. Therefore, the following factors shall be considered in the selection of cables in photovoltaic system: (1) insulation performance of cables; (2) Heat resistance and flame retardancy of cable; (3) Damp proof and light proof (radiation resistant) (4) cable laying method; (5) Material of cable conductor (copper core, aluminum alloy core); (6) Specification of cable section.
The cables used in the low-voltage DC transmission part of the solar photovoltaic power generation system have different requirements for the connection of different components due to different use environments and technical requirements. The factors to be considered generally include: the insulation performance, heat resistance and flame retardancy, aging performance, wire diameter specifications, etc. The specific requirements are as follows: the connecting cable between the solar cell module and the module is generally connected directly with the connecting cable attached to the module junction box. If the length is not enough, special extension cable can also be used. According to the different power of components, the sectional area of this type of connecting cable is 2.5m. The connecting cable between the storage battery and the inverter is required to use multi strand flexible cable passing UL test, and try to connect as close as possible. Selecting short and thick cables can reduce the loss of the system, improve efficiency and enhance reliability.
The characteristics of photovoltaic cable are determined by its special insulation material and sheath material, which we call cross-linked PE. After irradiation by the irradiation accelerator, the molecular structure of the cable material will change, thus providing its performance in all aspects. Mechanical load resistance In fact, during installation and maintenance, the cable can be routed on the sharp edge of the roof structure, and the cable must withstand pressure, bending, tension, cross tensile load and strong impact. If the strength of the cable sheath is not enough, the cable insulation layer will be seriously damaged, which will affect the service life of the entire cable, or lead to short circuit, fire, personal injury and other problems.
A large number of DC cables in the photovoltaic power generation system need to be laid outdoors, and the environmental conditions are harsh. The cable materials should be determined according to the resistance to ultraviolet radiation, ozone, severe temperature changes and chemical erosion. Long term use of ordinary cables in this environment will cause the cable sheath to be fragile, and even break down the cable insulation layer. These conditions will directly damage the cable system and increase the risk of cable short circuit. In the medium and long term, the possibility of fire or personal injury is also higher, greatly affecting the service life of the system.
