In recent years, under the support and guidance of relevant national policies, the solar photovoltaic power generation industry has developed rapidly, and the installed capacity of photovoltaic power plants has increased year by year. However, due to the relative lag in the research and development of domestic photovoltaic cables and their marketing efforts, in the construction and operation of photovoltaic power plants, the conventional cable is still used for connecting cables of photovoltaic power plants. Because the conventional cable does not consider the complicated and variable photovoltaic power station use and laying environment in the design and manufacturing process, it can not meet the requirements of use, resulting in frequent quality problems of photovoltaic power plants. In particular, the quality problems caused by the performance of the conventional cable itself cannot meet the requirements of the power station environment. The dedicated photovoltaic cable is designed according to the complex and variable use environment of the photovoltaic power station, which can meet the laying and operation requirements of the photovoltaic power station. The use of dedicated photovoltaic cables in photovoltaic power plants, especially on the DC side, can effectively reduce the occurrence of quality problems.
Photovoltaic power plants are built in all parts of China, which requires a wide range of temperature resistance of cables. For example, in the western and northern parts of China, cables are required to withstand lower temperatures. In some areas, extreme low temperatures can reach minus -40 °C. Even lower temperatures. In the eastern and southern parts of China, the surface temperature can easily reach above +70 °C. Considering that the working temperature of the conductor is higher than the ambient temperature and generating heat, it is possible to consider the extreme temperature in the area where the roof is not ventilated and the heat dissipation effect of the bridge is not good. Above +90 ° C, this requires the material temperature of the cable to meet the requirements of the station to work in extreme temperatures.
Frequent changes in temperature and humidity have a direct impact on the insulation of the material and the aging of the sheath, especially in areas with large daily temperature differences and large annual temperature differences and wet and rainy areas, which have a greater impact on the insulation and aging properties of the materials. Many of the power plants in China's fish-light complementary projects are directly built on fish ponds or water surfaces, requiring cables to work normally in humid environments for a long time. The performance of conventional cables does not take into account the influence of damp heat changes on the aging properties of materials. The design of photovoltaic special cables takes into account the factors affecting the aging properties of insulation and sheath materials. Therefore, qualified photovoltaic cables can meet the requirements of photovoltaic power plants. Temperature and humidity changes are required.
Photovoltaic power plants have long sunshine hours, and they are more resistant to sunlight. The sunlight contains a variety of rays, especially ultraviolet rays, which can accelerate the insulation of the cable and the aging of the sheath. Most of the cables of photovoltaic power plants are barely laid. The solar modules to the combiner box and even the cables to the inverter are mostly barely laid. This requires the cable to withstand the sunlight and ultraviolet radiation, and it can be guaranteed in daylight and UV rays are normally operated for a long time under vertical radiation. Therefore, qualified photovoltaic cables can work normally for a long time under the conditions of sunlight and ultraviolet radiation. However, under the conditions of daylight and ultraviolet radiation, the insulation and sheath of the conventional cable will accelerate aging, resulting in reduced or failed insulation performance. The problem of reduced protection.
Some PV power plants are built in special areas such as the sea and beaches. These areas have high levels of air salt spray. Some photovoltaic power plants are located in the former salt field, where the soil has a high salt content. Cables used under the above environmental conditions must have strong salt spray resistance and acid and alkali properties. Therefore, qualified photovoltaic cables are more resistant to salt spray and acid and alkali. The ozone content of some photovoltaic power stations is high, and ozone has a certain corrosive effect on the cable sheath, which accelerates the aging of the sheath and affects the use of the cable. Conventional cables do not take into account the effects of ozone on the cable sheath, which is considered in the design of photovoltaic cables. Therefore, even in areas with high ozone content, photovoltaic cables can work normally for a long time.
The above characteristics of photovoltaic cable can be applied to photovoltaic power plants under different environmental conditions to ensure long-term safe operation, while conventional cables are difficult to achieve this purpose. Therefore, in the construction of photovoltaic power stations, especially for some special photovoltaic power plant construction projects, the use of photovoltaic cables instead of conventional cables can effectively ensure long-term and stable operation of the power station, thus ensuring good long-term operational benefits of the power station.