The Need To Replace Conventional Cables with Photovoltaic Cables in Old Solar Power Plants

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 solar power stations has increased year by year. However, due to the relatively lagging development and marketing of domestic photovoltaic cables, in the construction and operation of solar power plants, the connecting cables of solar power plants still use conventional cables. Since the design and manufacture of conventional cables do not consider the complexity and changeability of the use and laying environment of photovoltaic power plants, they cannot meet the requirements of use, resulting in frequent quality problems in photovoltaic power plants. In particular, the quality problems caused by the performance of conventional cables cannot meet the requirements of the power station environment. Photovoltaic cables are designed according to the complex and changeable use environment of photovoltaic power stations, which can meet the requirements of laying and operation of photovoltaic power stations. The use of photovoltaic cables in photovoltaic power plants, especially on the DC side, can effectively reduce the occurrence of quality problems.

There are photovoltaic power plants built all over China, which requires cables to have a wide range of temperature resistance. For example, in western and northern China, cables need to withstand lower temperatures. In some regions, extreme low temperatures can reach -40°C. even lower temperatures. In eastern and southern China, surface temperatures can easily reach above +70°C. Considering that the operating temperature of the conductor is higher than the ambient temperature and generates heat, it can be considered that the temperature in the unventilated area of the roof is extreme, and the heat dissipation effect of the bridge is not good. Above +90°C, which requires the material temperature of the cable to meet the requirements of the station working at extreme temperatures.

Frequent changes in temperature and humidity have a direct impact on the insulation of materials and the aging of sheaths, especially in areas with large daily and annual temperature differences and humid and rainy areas, which have a greater impact on insulation and aging properties of materials. Many power stations in my country's fish-light complementary projects are built directly on fish ponds or water surfaces, and cables need to work normally in humid environments for a long time. The performance of traditional cables does not consider the influence of humidity and heat changes on the aging performance of materials. The design of photovoltaic cables takes into account the factors that affect the aging performance of insulation and sheath materials. Therefore, qualified photovoltaic cables can meet the requirements of photovoltaic power plants. Changes in temperature and humidity are required.

Photovoltaic power plants have a long sunshine time and are more resistant to sunlight. Sunlight contains a variety of rays, especially ultraviolet rays, which will accelerate the aging of cable insulation and sheaths. Most of the cables for photovoltaic power plants are barely laid. The cables connecting the solar modules to the combiner boxes and even the inverters are mostly barely laid. This requires the cable to withstand sunlight and ultraviolet radiation, and to ensure that it can work normally for a long time under sunlight and vertical radiation. Therefore, qualified photovoltaic cables can work normally for a long time under the conditions of sunlight and ultraviolet rays. However, under the conditions of sunlight and ultraviolet radiation, the insulation and sheath of conventional cables will accelerate aging, resulting in reduced insulation performance or failure. The problem of reduced protection.

Some photovoltaic power plants are built in special areas such as seasides and beaches. Air salt mist levels in these areas are high. Some photovoltaic power plants are located in former salt fields, and the soil has a high salt content. Cables used under the above environmental conditions must have strong salt spray and acid and alkali resistance. Therefore, qualified photovoltaic cables are more resistant to salt spray and acid and alkali. Some photovoltaic power stations have high ozone content, 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 consider the effect of ozone on the cable sheath, which is considered in the design of photovoltaic cables. Therefore, even in areas with high ozone content.

The above characteristics of photovoltaic cables 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 some special photovoltaic power station construction projects, the use of photovoltaic cables instead of conventional cables can effectively ensure the long-term stable operation of the power station, thereby ensuring the benefits of good long-term operation of the power station.