On December 23, 2020, the world's first black start project of 9F heavy-duty gas turbine through energy storage was successfully launched in Zhuhai Hengqin Thermal Power Co., Ltd., and officially put into commercial operation.
Typhoon disasters occur frequently in China's coastal areas, which requires a high capacity of power disaster prevention and mitigation in Guangdong, Hong Kong and Macao area. Effectively improve the power supply capacity of Macao and the ability of the main power supply to resist typhoon disasters, and actively strengthen the construction of local supporting power supply to enable it to have the ability to operate in isolated grids and "black start" function. “Black start" refers to that when there is a major power system failure or the whole system blackout, the generator units without self-starting ability can be restarted without the support of power grid, gradually expanding the scope of recovery, and finally restoring the power supply of the whole system. Hengqin thermal power is responsible for the cold and hot power supply of Zhuhai Hengqin free trade zone and the supply to Macau Electricity Company. It is an ideal black start power point.
Hengqin thermal power black start system is equipped with 22MW / 20MWh lithium battery energy storage system, which is matched with two 390MW 9F gas steam combined cycle units. When the power supply is normal, the system assists gas turbine frequency regulation, participates in power spot market transactions, and improves frequency, voltage support capacity and unit operation stability; when the power grid encounters major disasters and large-scale power failure, the system realizes the black start of gas turbine through the energy storage system, and quickly restore the power supply.
The project is the first energy storage auxiliary gas turbine frequency regulation project in China and the first 9F heavy-duty gas turbine energy storage black start project in the world. As a well-known energy storage system solution provider, NR has industry-leading energy storage converter control technology and system integration capability. This time, NR has provided a complete set of key equipment such as Power Conversion System (PCS), Power Management System (PMS), SCADA and Power Measurement Unit (PMU). With deep understanding of power system and static frequency converter (LCI) and excitation control technology, NR developed black start control, simulation, implementation and testing scheme to ensure the smooth implementation of the project.
The core challenge of black start is the control of energy storage system. In order to solve the problems of voltage source mode operation stability and synchronization control of dozens of energy storage units in the process of black start. NR adopts the system impedance independent matching technology to realize the off grid parallel operation of 44 energy storage converters for the first time. The power balance deviation is less than 0.5%, which greatly improves the system load. The core technologies such as frequency and voltage multi-level stability control and active real-time synchronization control are adopted to achieve accurate synchronization, with synchronous angle difference < 2 °, frequency difference < 0.01Hz and amplitude difference < 1%, greatly reducing synchronous closing impact.
In the implementation stage, facing the urgent problems of short unit outage time and black start commissioning, the project team carried out the work against the clock on the basis of full research and preparation in the early stage, and successfully completed more than 200 steps of black start testing in just 12 hours. After the project is put into operation, the black start of the unit can be realized within 30 minutes. NR’s excellent technology, high-quality products and professional services have won the high recognition of all parties!
The smooth operation of the project will greatly improve the power supply and guarantee capacity of Hengqin thermal power. It is an innovative application of battery energy storage technology combined with traditional power supply, which is of milestone significance. As an international leading power automation and energy storage system solution supplier, NR will continue to research and explore more innovative power technology application to improve the reliability for power system.