The world's largest Three Gorges Project and the world's largest hydroelectric generating unit attracts and gathers a group of domestic manufacturers of large-scale hydro-generator units. With its unique advantages, it strives to win the competition. On the left bank of the Three Gorges Project, 14 sets of 700MW hydroelectric generating units are invited for international bidding, requiring bidders to take full responsibility for the technical and economic aspects of providing equipment. They are required to jointly design and manufacture with Chinese qualified manufacturing enterprises, and transfer technology to Chinese manufacturing enterprises. The proportion of subcontracted shares of Chinese manufacturing companies is not less than 25% of the total price. The latter two units are mainly Chinese manufacturing enterprises. Foreign large-scale hydropower equipment manufacturers form five joint venture bids to form a competitive situation. In the project construction, Harbin Electric and Dongdian participated. Hadian and Dongdian have decades of experience in designing and manufacturing large-scale hydro-generator units. In the past 20 years, under the support of the relevant state departments, the Three Gorges unit has been engaged in scientific and technological research, digestion and absorption of imported technology has been effective, and hydraulic turbine design has been mastered. With the model test, generator electromagnetic design, calculation of large component strength and stiffness, calculation and testing of thrust bearing, calculation of shafting stability, calculation of generator ventilation and cooling, and special key technologies, we can independently develop and design large-scale hydro-generator units. And with foreign companies to overcome a number of technical problems.
First, hydraulic turbine design and model runner research problems. Turbine hydraulic design and model runner study is the key to determine the turbine performance. The International Electrotechnical Commission IEC provides that a model runner acceptance test is performed on a turbine test stand that meets the requirements as a basis for checking whether the turbine performance satisfies the terms of the contract. Domestic and foreign hydro turbine manufacturers have been conducting research on energy, cavitation and stability at the hydraulic test bench. The tendering of the left bank of the Three Gorges has resulted in fierce competition. The energy and cavitation performances of the two selected model rotors of VGS (GE Canada) and Alstom (Kvaemer, Norway) fully meet the requirements of the contract. There is no cavitation within the operating range, which represents the most important performance of turbines in the world today. Good level. In only 3 years, the efficiency of the Francis turbine in Zhongshui has increased by 1 to 1.5 percentage points, which is a big improvement.
In recent years, the development of large-capacity hydro-generating units at home and abroad has increased the size of components, resulting in weakening of structural rigidity and widespread vibration problems. The capacity and component size of the Three Gorges unit are the largest in the world, and this has caused the company's great attention. Harbin Electric and Dongdian applied the hydraulic design of the imported technology and retested the Three Gorges turbine runner on a hydraulic test bench conforming to international standards. Several optional wheels were calculated and tested on the optional parameters. The experimental results showed that The same level of introduction of technology. At present, this technology is applied to the research and development of 700MW hydroelectric generating sets in Yunnan Xiaowan and Longtan in Guangxi, and the effect is also good.
Second, ensure the safe operation of the hydro-generator thrust bearing. The Three Gorges thrust bearing load is currently the largest in the world. Each manufacturing company has its own traditional structure and operating experience. VGS (GE Canada) uses an oil-impregnated outer circulation structure of a babbitt alloy tile material supported by a small coil spring cluster. The diameter of the mirror plate is 5.4m. Alstom (ABB) uses different diameters of the cylindrical column to support the double-layered tile of the Babba alloy. Material immersion oil outer circulation structure, mirror plate diameter 5.2m, thrust bearing parameters are within the conventional range. ABB cooperated with Harbin Institute of Electrical Engineering and Technology Co., Ltd. to complete a full-load test on a 3000-ton thrust bearing test bench with half a real machine thrust shroud to determine the actual operation data of each unit and ensure the reliable operation of the unit. In technology exchanges with foreign countries, domestic enterprises have further learned about the operating experience of Russian power plants in the use of flexible metal plastic tile facing materials. At present, many domestic hydropower stations have been adopted and are generally welcomed by users. Based on years of experience in designing, manufacturing, and operating in China, combined with the introduction technology of the Three Gorges unit, domestic manufacturing companies have mastered the design and manufacturing technology of large-scale thrust bearings, which can give full play to the favorable conditions for thrust bearing testing in China and continue to support thrust bearings. The research work on the structure and elastic metal plastic tile is applied to the Three Gorges right bank unit.
Third, improve the reliability of generator stator bar insulation and generator life. Since the thermal insulation grade of stator stator bar insulation has been increased to Grade B and Grade F, there are two major technological schools in the world: One is a manufacturing company represented by Westinghouse (including ABB, Siemens, etc.), using a small tape VPI. After the process, that is, after being encapsulated with a low mica tape, the vacuum in the can is used to heat and insulate the resin to heat and cure the insulation. The production efficiency is high. Secondly, the company is represented by GE (including the Russian power plant, the French company Alstom, etc.) Enterprises, the use of multi-tape hydraulic process, that is, with a polyacryl adhesive tape containing curing agent, a number of wire rods into the tank hydraulic process, using asphalt as a medium heating and pressure to make the insulation curing. Through technological improvements and the inspection of the Three Gorges Project, the quality of the stator bars produced by Harbin Electric and Dongda Electric was generally favored by people in the industry. Foreign businessmen agreed that Harbin Electric and East Electric were manufactured using multi-tape molding technology and approved by China Three Gorges Corporation. Each of the two stator bars in the subcontract was provided by domestic companies. It is indeed a major step forward for domestic manufacturers to use generators for generators that are responsible for foreign technology. This will lay the foundation for the development of this technology in China.
First, hydraulic turbine design and model runner research problems. Turbine hydraulic design and model runner study is the key to determine the turbine performance. The International Electrotechnical Commission IEC provides that a model runner acceptance test is performed on a turbine test stand that meets the requirements as a basis for checking whether the turbine performance satisfies the terms of the contract. Domestic and foreign hydro turbine manufacturers have been conducting research on energy, cavitation and stability at the hydraulic test bench. The tendering of the left bank of the Three Gorges has resulted in fierce competition. The energy and cavitation performances of the two selected model rotors of VGS (GE Canada) and Alstom (Kvaemer, Norway) fully meet the requirements of the contract. There is no cavitation within the operating range, which represents the most important performance of turbines in the world today. Good level. In only 3 years, the efficiency of the Francis turbine in Zhongshui has increased by 1 to 1.5 percentage points, which is a big improvement.
In recent years, the development of large-capacity hydro-generating units at home and abroad has increased the size of components, resulting in weakening of structural rigidity and widespread vibration problems. The capacity and component size of the Three Gorges unit are the largest in the world, and this has caused the company's great attention. Harbin Electric and Dongdian applied the hydraulic design of the imported technology and retested the Three Gorges turbine runner on a hydraulic test bench conforming to international standards. Several optional wheels were calculated and tested on the optional parameters. The experimental results showed that The same level of introduction of technology. At present, this technology is applied to the research and development of 700MW hydroelectric generating sets in Yunnan Xiaowan and Longtan in Guangxi, and the effect is also good.
Second, ensure the safe operation of the hydro-generator thrust bearing. The Three Gorges thrust bearing load is currently the largest in the world. Each manufacturing company has its own traditional structure and operating experience. VGS (GE Canada) uses an oil-impregnated outer circulation structure of a babbitt alloy tile material supported by a small coil spring cluster. The diameter of the mirror plate is 5.4m. Alstom (ABB) uses different diameters of the cylindrical column to support the double-layered tile of the Babba alloy. Material immersion oil outer circulation structure, mirror plate diameter 5.2m, thrust bearing parameters are within the conventional range. ABB cooperated with Harbin Institute of Electrical Engineering and Technology Co., Ltd. to complete a full-load test on a 3000-ton thrust bearing test bench with half a real machine thrust shroud to determine the actual operation data of each unit and ensure the reliable operation of the unit. In technology exchanges with foreign countries, domestic enterprises have further learned about the operating experience of Russian power plants in the use of flexible metal plastic tile facing materials. At present, many domestic hydropower stations have been adopted and are generally welcomed by users. Based on years of experience in designing, manufacturing, and operating in China, combined with the introduction technology of the Three Gorges unit, domestic manufacturing companies have mastered the design and manufacturing technology of large-scale thrust bearings, which can give full play to the favorable conditions for thrust bearing testing in China and continue to support thrust bearings. The research work on the structure and elastic metal plastic tile is applied to the Three Gorges right bank unit.
Third, improve the reliability of generator stator bar insulation and generator life. Since the thermal insulation grade of stator stator bar insulation has been increased to Grade B and Grade F, there are two major technological schools in the world: One is a manufacturing company represented by Westinghouse (including ABB, Siemens, etc.), using a small tape VPI. After the process, that is, after being encapsulated with a low mica tape, the vacuum in the can is used to heat and insulate the resin to heat and cure the insulation. The production efficiency is high. Secondly, the company is represented by GE (including the Russian power plant, the French company Alstom, etc.) Enterprises, the use of multi-tape hydraulic process, that is, with a polyacryl adhesive tape containing curing agent, a number of wire rods into the tank hydraulic process, using asphalt as a medium heating and pressure to make the insulation curing. Through technological improvements and the inspection of the Three Gorges Project, the quality of the stator bars produced by Harbin Electric and Dongda Electric was generally favored by people in the industry. Foreign businessmen agreed that Harbin Electric and East Electric were manufactured using multi-tape molding technology and approved by China Three Gorges Corporation. Each of the two stator bars in the subcontract was provided by domestic companies. It is indeed a major step forward for domestic manufacturers to use generators for generators that are responsible for foreign technology. This will lay the foundation for the development of this technology in China.
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