Foreign research on microgrids started early, and some breakthroughs have been made in key technologies, which have been verified in small-scale microgrids. Among them, the United States, Europe, Japan and Canada have built a number of demonstration projects, providing some experience and reference for the development of microgrids, and have become leading countries in the field of microgrids. Foreign countries are promoting the development of microgrids to higher voltage levels and larger capacities.
Domestic microgrid research is in its initial exploration stage, and the State Grid Corporation of China is the main institution for microgrid technology research. In August 2011, the microgrid technology system research project of the State Grid Electric Power Research Institute passed the acceptance inspection. This project proposed for the first time China's microgrid technology system, covering the core technology framework of microgrids, the power grid's strategies for dealing with microgrids, technical standards and policies, etc., and formulated the development route and technology roadmap of my country's microgrids, and analyzed the different development stages of my country's microgrids. Provided positive comments and suggestions.
Hebei, Tianjin, Henan, Zhejiang, Zhuhai and other places are already conducting research and construction of microgrid demonstration projects. Among them, the completion of the Zhuhai Dong'ao Island microgrid project has solved the long-term power shortage on the island, making maximum use of the island's abundant sunlight and wind resources, and minimizing the use of diesel power generation to provide green power. With the operation of the entire microgrid system, the proportion of renewable energy power generation in Dongao Island has increased from 30% to 70%.
In August 2015, the Yantai Changdao distributed power generation and microgrid access control project passed the acceptance inspection by the National Development and Reform Commission and was officially completed and put into operation. This is the first island microgrid project in northern my country. It can realize isolated grid operation to ensure continuous power supply to important users when the external large power grid collapses, greatly improving the power supply capacity and reliability of the Changdao Power Grid.
The analysis of the microgrid industry research group believes that microgrids are a powerful supplement to large power grids and an important part of the smart grid field. They have broad application prospects in industrial and commercial areas, urban areas and remote areas. As the research and development progress of key microgrid technologies accelerates, microgrids are expected to enter a period of rapid development.
Domestic research on microgrids has made some progress. However, compared with the huge research teams composed of research institutions, manufacturers and power companies in Europe, the United States and Japan, our country’s research strength and achievements are limited. There is still a big gap.
1. There is a lack of unified and standardized technical standards and specifications for microgrid systems.
At present, there are no unified and standardized technical standards and specifications for microgrid systems in China, which has greatly affected the research on microgrid technology and the construction of demonstration projects.
2. The application level of power electronics technology in microgrids is not high.
The development of microgrid technology is closely related to advanced power electronics technology, computer control technology, and communication technology. According to the special needs of microgrids, it is necessary to study the power electronics technology used and develop some new power electronic equipment.
3. The protection and control technology of microgrid is not yet mature.
4. High investment and operation and maintenance costs.
The isolated operation of microgrid requires the configuration of an energy storage system with a certain capacity, and the investment cost of energy storage system construction is relatively high. The larger the capacity configuration of the energy storage system, the better the effect, but the higher the cost. It is necessary to find a better balance point, which is closely related to the operation requirements of the microgrid, peak and valley electricity price policies, etc. Microgrid monitoring platforms and energy management systems have high investment costs. The operation and maintenance costs are also higher than those of ordinary power grids.
On July 22, 2015, the National Energy Administration issued guidance on promoting the construction of new energy microgrid demonstration projects. New energy microgrid projects can rely on the construction of existing distribution networks, or they can be combined with new ones. Distribution network construction; it can be a single new energy microgrid or a microgrid group composed of multiple new energy microgrids in a certain area.
The National Energy Administration encourages the use of advanced Internet and information technology in the construction of new energy microgrids in accordance with the concept of Energy Internet to achieve intelligent matching and coordinated operation of energy production and use, and in the form of new business formats Participate in the electricity market and form a new carrier of efficient and clean energy utilization. According to estimates based on the number of microgrid demonstration projects and global market capacity share, the incremental market for microgrids during China’s “13th Five-Year Plan” period is approximately 20 billion to 30 billion yuan, which does not include the original photovoltaic and distribution networks. , electric vehicles and energy storage needs.
Learned from the "Photovoltaic Micro Lecture Hall Huangpu Phase I" Microgrid Key Technology and Development Trend Forum held on August 30, 2015. Experts involved in the 13th Five-Year Plan believe that the arrival of renewable energy is an inevitable trend and microgrids have broad market prospects. At present, microgrid technology, economics, and business models still need to be demonstrated. The focus is to promote and demonstrate renewable energy micro-energy networks and explore the most technically and economically feasible new business models.
“Microgrid is mainly about the integration of power energy production and consumption within the same power user or local area, including the intelligent control of power consumption by small power operation management systems. The first is the specific implementation of smart grid at the user end. ization, followed by an upgraded version of distributed energy, which combines the free use of renewable energy with the efficient use of conventional energy, and is an important carrier to promote the transformation of energy development and operation and management methods,” National Energy Administration New Energy and Renewable Energy. Liang Zhipeng, deputy director of the department, explained at the forum.
At the same time, microgrids are also a new business format after the new round of power system reform, and are a specific way to open up the power grid distribution side to social entities. In Liang Zhipeng's view, microgrid operations should be conducted by entities other than power grid companies, and it is easier to diversify investment entities than on the distribution network side.
It is understood that compared with the United States, Japan and Europe, my country's microgrid research started relatively late, and is generally in the research and demonstration stage of technology, economy, and business models. Recently, the construction of microgrid projects has been officially elevated to the national level. On July 21, the National Energy Administration announced the "Guiding Opinions on Promoting the Construction of New Energy Microgrid Demonstration Projects", requiring that in remote areas and islands not covered by the power grid, Prioritize the new energy microgrid method and explore independent power supply technology and new management models.
Liang Zhipeng said that from now on, many projects are called microgrids, but they are difficult to serve as demonstrations. New energy microgrid refers more to the efficient utilization of distributed conventional energy sources such as distributed renewable energy and natural gas. Among the current demonstration project applications, there are many in eastern regions such as Zhejiang and Jiangsu.