At 14:27 on May 26, the first phase of pure new energy black start test of the "source grid load storage" micro grid demonstration project in Ejina area of Inner Mongolia Power Group was successfully put into operation, which broke the dependence of traditional power system operation on conventional rotating units, opened up a new application scenario for the development of grid energy storage, and provided an important reference for the construction of the national new energy system.

As the first pure new energy black start test in China, Inner Mongolia Electric Power Company attaches great importance to, coordinates and compiles 15 test plans and calculation reports of high quality, ensuring the safe and smooth implementation of the test from all aspects of organizational measures, safety measures, and technical measures.

This experiment uses a grid type energy storage device as the starting power source, and spans three voltage levels (110 kV, 35 kV, and 10 kV) while the microgrid is completely off the grid. It spans a wide grid area of 262 kilometers and 110000 square kilometers from east to west in Ejina Banner, supporting two new energy stations for grid connected power generation, forming a pure new energy microgrid of three (grid type energy storage stations, photovoltaic power stations, and decentralized wind farms), four stations, and seven lines. It will effectively alleviate the problem of a single power supply in the Ejina region.

It is reported that the grid type energy storage system not only has the characteristics of peak to valley shift, smooth new energy, black start, power backup and other conventional energy storage functions, but also achieves power self - synchronizationchronization control by controlling the amplitude and phase angle of the internal potential, presenting voltage source characteristics. It can effectively improve the inertia and short-circuit capacity of the system, improve the damping characteristics of the power grid, and provide fast dynamic reactive power compensation, enhancing voltage support for the power grid, It is the cornerstone of stable operation of weak regional power grids. The application of grid type energy storage in the Ejina project has solved the problem of system stability in the promotion of "source network load storage" in the region in recent years. It supports the frequency, voltage, and short-circuit current of the system, improves its resilience, and ensures stable operation of the system.

At 14:34 on May 26th, the pure new energy black start system achieved load power supply. By 15:32, the photovoltaic power plant and wind farm were connected to the grid for normal power generation, and after continuous and stable operation for 22 minutes, they were successfully integrated into the Mengxi power grid. This fully verified the power self synchronization control ability and voltage source support characteristics of the grid type energy storage device, accumulating valuable experience for the second phase of the Ejina Banner full area grid medium and long-term operation test.

It is reported that this test is the third power supply emergency recovery method of Mengxi Power Grid after the black start test of Wanjiazhai hydropower units and the black start test of Hohhot pumped storage power station, greatly improving the power supply guarantee and emergency capacity of Mengxi Power Grid in remote areas.