On June 7th, Dongfang Electric Group completed the localization transformation of the domestically developed largest single unit capacity impact hydroelectric unit, which was successfully connected to the grid for power generation at the Jinwo Hydropower Station of Sichuan Investment Group. This marked the successful application of Dongfang Electric Group's first domestically produced 150 MW large impact turbine with fully independent intellectual property rights throughout the entire industrial chain, and opened a new chapter in the high-quality development of China's hydropower industry.
The runner is the core component of a hydroelectric unit and is known as the "heart" of the unit. The first domestically produced 150 megawatt large impact turbine was applied to the impact turbine unit of Jinwo Hydropower Station of Sichuan Chuantou Tianwanhe Development Co., Ltd. The wheel weighs about 20 tons and has a maximum diameter of about 4 meters. It was successfully taken off the production line at Dongfang Electric Group on May 16th.
Relying on the localization project of a 150 megawatt large-scale impact runner, Dongfang Electric Group has achieved complete autonomy in the hydraulic development, shape design, software development, and model device development of the impact runner, filling multiple domestic technological gaps. Breakthrough has been made in key core manufacturing technologies such as runner structure design, material application, and processing technology, We have achieved a historic breakthrough in the key core technology of China's high head and large capacity impulse hydroelectric units, which has emerged from scratch.
It is understood that in response to the major strategic demand of the country's "accelerating the construction of the Southwest Hydroelectric base", Dongfang Electric Group has formulated a "three step" climbing plan for the development of a 150 megawatt large impact turbine, a 500 megawatt giant impact turbine, and a 700-1000 megawatt high head and large capacity giant impact turbine. Since 2019, Dongfang Electric Group has made every effort to organize research on key core technologies of high head and large capacity impulse hydropower units. It has collaborated with research institutes and upstream and downstream enterprises to carry out technological breakthroughs, focusing on, systematically, and comprehensively breaking through the "bottleneck" problem of impulse hydropower unit development. It has established a high-quality and efficient development model that integrates multiple disciplines, innovates, and cooperates internally and externally for win-win results, forming a large-scale impulse runner research and development, design Technical system for the entire manufacturing and inspection process.
In terms of hydraulic development, innovative 3D modeling design ideas have been developed, and a fully intellectual property owned 3D modeling design software for bucket leaves has been independently developed, solving the problems of autonomous design and fast and accurate geometric modeling. Mastered the advanced semi open and semi closed full flow field multiphase CFD simulation analysis method, effectively improving the efficiency of hydraulic development and optimization design. We have built an intelligent, high-precision, and internationally leading DF300 impulse turbine model test bench, achieving all testing functions with one click.
In terms of structural design, more than 100 schemes were validated and analyzed, and the three-dimensional high-order complex surface shape of the runner was optimized. The stress distribution was optimized to ensure that the cyclic fatigue life of the runner was not less than 1.5 billion times, and it could withstand 1.5 billion impacts of 110 to 220 tons of force. Taking into account the differences in vibration form, excitation frequency, and natural frequency of the runner in different media, the system has mastered the stiffness and strength, dynamic characteristics, dynamic stress analysis, and testing methods of the runner. From scratch, it has solved the problems in the design of large impact type runner structures, ensuring excellent performance and safe and reliable structure of the runner.
In terms of process manufacturing, a stress distribution based segmented method and manufacturing methods are adopted, and high-precision CNC machining processes are applied to ensure the reliability of the runner operation. The center body adopts a combination of forgings and composite additives to effectively compress the specifications of forgings and release the manufacturing risks of large forgings. The external water bucket adopts three methods: die forging, electroslag casting, and additive manufacturing, effectively verifying the applicability of different manufacturing methods. The use of laser cladding and surface nano manufacturing technology has effectively improved the anti sediment erosion performance of the runner, accumulating valuable experience for the development of higher water head and larger capacity impact type runners.
It is reported that Dongfang Electric Group will take the application of the 150 megawatt large impact turbine project as an opportunity, and according to the established "three step" plan, further strengthen joint innovation, work with domestic energy enterprises, and jointly promote the demonstration application of the 500 megawatt impact hydroelectric unit project with world influence, and continue to develop the 700 to 1000 megawatt high head and large capacity impact hydroelectric unit, Continuously promote the high-quality development of China's hydropower industry.
