In order to support the clean transition of the energy structure and the energy consumption revolution, the national key R&D program initiated the implementation of the 'Smart Grid Technology and Equipment' key special project. To improve the full consumption and utilization efficiency of distributed energy, a multi-energy complementary distributed supply system was set up. With the direction of micro-grid technology, as an important practice of this technology, in early 2016, State Grid Jiangsu Power and the Lianyungang Border Detachment team worked together to build an “AC-DC hybrid” island smart microgrid on the Cheoniushan Island in Lianyungang. It was put into trial operation in December 2017 and officially put into operation on April 25, 2018. The project was equipped with the first domestic AC/DC hybrid, three-port converter, which provided effective power for high-quality electricity in offshore islands. solution.
Up to now, Che Niangshan Microgrid has produced 57,600 kWh of electricity, purified 61 tons of fresh water, and has become self-sufficient in power supply and water supply. It has changed the history of relying on supplying ships to deliver diesel power on a regular basis. The project is based on the AC-DC hybrid of power electronic transformers. The successful research of distributed renewable energy technology research is also a substantial advancement of the national key R&D project implementation projects, and it has continued reliable electricity use in all areas of China's 'high seaside, no' (high altitude, island, border defense, and no-man's) areas. It is of great significance.
At present, there are 6536 islands with an area of more than 500 square meters in China, of which more than 400 are inhabited. Most are small and medium-sized islands far from the land. For these islands, continuous and stable electricity supply has always been a luxury.
'The island where we stationed is far from the mainland. The normal support guarantees all rely on land transportation. It is very inconvenient to use water for electricity. To solve this problem, our detachment installed wind and photovoltaic generator sets on the island. Now that we have a smart microgrid. , Power supply, water supply are no longer a problem, when the weather is good, can send more than 400 kWh a day, like air conditioners, electric water heaters, these high-power appliances are completely useless, can enjoy the same life as the land. On the improvement of life, Sun Quan, head of the Lianyungang Che Niushan Island Border Guard Station in Lianyungang, said with emotion that Sun Quan’s Che Niushan Island is located in the northeast of Lianyungang, 47.5 kilometers from the land, with a total area of 0.06 square kilometers. The mobile communication base station on the island, Marine signal stations and border defense units have long depended on diesel engines, photovoltaics, etc. to supply electricity. Like other islands far from the mainland, there are problems such as insufficient power supply stability, low automation level, and shortage of drinking water.
“The Che Niangshan microgrid project makes full use of AC/DC hybrid distributed renewable energy technology based on power electronic transformers. The 'three-port converter' is the biggest highlight of this project. With its microgrid on the island, it has The 'brains' that can be thought of can intelligently schedule the island's wind power, photovoltaic, and battery power, making the island's electricity as stable and reliable as the land. 'Yuan Xiaodong of the State Grid Jiangsu Institute of Electrical Science and Technology said.
'In the past, electricity supply was unstable. In the winter, an average of only 3 hours of electricity was used per day. Water was mainly supplied by regular supplies and rainwater. It barely met the basic domestic water demand. Now that the electricity supply is stable and sufficient, a desalination system is also installed. , Every day, I can wash my hot bath. 'Recruits Chen Hu didn't quite adapt to the life of the defending island, but every day he was able to wash his hot bath to make him feel at home, and 'the amount of photovoltaic and wind power In big weather, it is also convenient to store excess water for desalination of seawater.
After the smart microgrid of Che Niangshan Island was completed, various power points and electrical equipment on the island were interconnected. Under different weather conditions, electrical energy between different users can be mutually complementary, and a 50 kW fan on the island was realized. Comprehensive utilization of island energy of 30 kW photovoltaic, 100 kW diesel engine and 450 kWh energy storage.
It is understood that the AC-DC hybrid smart microgrid of Cheniuyama Island is based on photovoltaics, wind power and other green energy sources, and is based on the 'three-port converter'. It is constructed of an AC-DC hybrid consisting of border defense, mobile, and maritime. The microgrid uses energy management systems to precisely coordinate power generation, energy storage, and power usage, and flexibly deploys the connection methods of each user to achieve coordinated control and economic operation of 'source-network-load-storage'.
As the core of the AC/DC hybrid intelligent microgrid, the 'three-port converter' also enables the remote control of the island's power grid with a 'remote control', and the power grid professional operation and maintenance personnel in tens of kilometers away are not leaving home. It can carry out real-time monitoring and remote diagnosis on the island's power grid and electricity equipment, and effectively solve the problem that the island lacks professional grid operation and maintenance personnel far from the mainland, and island grid cannot be monitored, operated and maintained in a timely manner.
It is understood that the State Grid Jiangsu Electric Power is developing the first domestic four-port microgrid router. This technology is currently at the world's leading level and will be piloted in the new energy town of Tongli, Suzhou. It will be built in the direction of cleanliness and electricity as the center. Taking the power grid as a platform and taking electrical energy as the key, the modern energy system with a variety of energy sources complements each other and leads the direction of energy development in modern cities.