The development trend of photovoltaic inverter industry

As the types of power stations become more and more complex, the product spectrum of inverters will become more diversified to meet the needs of different application scenarios. Specifically, it is mainly manifested in the following six aspects.

1. The rapid development of inverter hardware

The application of various new devices such as SiC, CAN, and high-performance DSP and new topologies have promoted the continuous improvement of the efficiency of inverters. At present, the maximum efficiency of inverters has reached 99%, and the next target is 99.5%; China’s efficiency has been To reach A level, the next goal is A+, A++.

2. The power of the centralized inverter is increased, the efficiency is increased, and the voltage level is increased

Inverters of higher power levels such as 2.5MW will be widely used. Compared with the 1MW square array, the 2.5MW solution can reduce the cost by about 0.1 yuan/W, that is, a 100MW power station can reduce the initial investment by 10 million. In addition, after the cable is matched, the loss of the DC part is guaranteed to be consistent.

It is worth mentioning that the 1500V system will be the development trend of large power stations. Compared with a 1000V system, it can save 0.2 yuan/W of investment in addition to components, which is equivalent to saving 20 million yuan in investment for a 100MW power station. At the same time, the system loss can be reduced by about 0.27%.

3. Stand-alone power of string inverters continues to increase, and power density increases

The power of string inverters continues to increase, and the current maximum power has reached 80KW, the power density is also continuously increasing, and the weight is constantly decreasing to adapt to the complex application environment where installation and maintenance are difficult. Sungrow's 40KW string inverter has achieved 39kg, which is currently the lightest 40KW product in the industry. In terms of heat dissipation, Sungrow has always adhered to the way of smart fan heat dissipation to further reduce the temperature rise of internal components and improve the overload capacity of the inverter in high temperature environments. The used fan has an IP65 protection level, and its life span can reach 70,000 hours. At the same time, the fan can provide a 20-year warranty.

4. Component-level products are becoming more and more abundant

Component-level products are becoming more and more diverse, such as micro-inverters represented by Enphase, and power optimizers represented by SolarEdge. According to industry research organization GTM, shipments of component-level power electronic equipment will increase from 1.1GW in 2013 to more than 5GW in 2017.

5. The adaptability of the power grid has been continuously enhanced, and various protections have been improved to ensure safety and reliability

Leakage current protection, SVG function, LVRT, DC component protection, insulation resistance detection protection, PID protection, lightning protection, PV positive and negative reverse connection protection and other continuous improvement functions, the inverter's ability to adapt to the grid has been further enhanced and continuously improved The protection function makes the system safer and more reliable.

6. The environmental adaptability of inverters continues to improve

With the increase in the application of photovoltaic power plants in various harsh environments such as coastal, desert, plateau and other harsh environments, the environmental adaptability of inverters such as corrosion resistance and wind and sand resistance has been continuously improved to ensure high reliability in harsh environments.