Independent research and development of solar energy grid-connected inverter devices in China

Fudan University, South China University of Technology, and Shanghai Communications University have jointly researched and developed three series of 10 products, including megawatt-level grid-connected inverters, after three years of joint research, and recently passed the National Energy Board’s organization. The expert appraisal, and won the "double A" award in the open test of the international authoritative organization PHOTON in 2011, the core technology index ranks first in Asia. Relevant experts believe that this important achievement is of great significance for breaking the monopoly of foreign enterprises, improving the independent supporting capabilities of the core devices in China's photovoltaic industry chain, and realizing the large-scale industrialization of large-capacity photovoltaic grid-connected power stations.

According to the research group leader Dr. Sun Yaojie of Fudan University, “Double A” refers to the two core indicators of the conversion efficiency of the inverter device and the maximum power point tracking efficiency. Solar panels convert radiant energy into DC energy, and the conversion rate is generally between 15% and 17%. The inverter device converts DC power into AC power. The same efficiency loss needs to be overcome. The current highest level of global technology conversion efficiency is 97.7%. The device developed by our scientists is 97%.

At present, the product has passed the grid access licenses of seven countries including Germany, the United Kingdom, and Spain, as well as the certification testing of international authoritative organizations such as PHOTON, VED, and BV, and has obtained the “Golden Sun” certification from the China Quality Certification Center as the only one in China. The selected products were selected together with the products of internationally renowned company Emerson to be selected as a large-scale photovoltaic power station for demonstration application of 3,887 meters above sea level in the southernmost region of Tibet, China.

The grid-connected inverter device is the most important technology product in the solar photovoltaic industry. The developed countries in the world have attached great importance to it. Currently, many large-scale grid-connected inverters have been established in Europe and America. Due to the lack of original high-end technology in China, most of the inverter devices in China's solar photovoltaic industry rely on imports, which has become a major deterrent to the development of the photovoltaic industry. In the planning, China will add 20,000 megawatts of installed capacity of photovoltaic power stations in 2020. The integration of high-efficiency, high-performance, long-life, and integrated megawatt-class high-power inverter devices that meet the grid's high penetration rate will become the key.

Through the transformation of industry, universities and research institutes, Fudan University and several universities have achieved breakthrough results in the areas of “megawatt high-precision real-time control and circuit optimization” and “smart grid access and new energy coordinated control technologies”, and solved high-performance photovoltaics. The core technical issues of the power generation network.

It is reported that the cumulative installed capacity of the photovoltaic demonstration power station at home and abroad for the past three years has exceeded 600 megawatts, and the economic benefits have reached 900 million yuan. With the close proximity of core technical indicators, the price of the product is only 1/3 of that of German products. It is understood that the research group has successfully applied for 6 patents, and on this basis, the new R & D and exploration of inverter equipment corrosion resistance, withstand bad weather conditions.