Wuxijiang Huangtankou Hydropower Station consists of Level-II station built for the development of Wuxijiang River Basin, equipped with two sets of 26 MW Francis turbine units (Units 5# and 6#). The water diversion system includes dam-type water inlet and water diversion pressure pipeline, and the power-generation inlet is formed by the renovation of the east two overflow orifices. The water diversion pipe adopts φ5.8m steel pipe poured with reinforced concrete of 60cm in thickness, and is about 152m long. Water is diverted in the form of single unit and single pipe. Two water-diversion pipes are 139.74m and 143.26m in length.
The designed value of rated output for single unit of Turbine Generators 5# and 6# in Huangtankou Hydropower Station reaches 26 MW. Since operation in 1995, they could operate in a relatively stable way, but the problem of insufficient output always existed. According to the statistical analysis of the actual operation for many years, the single output could only reach 24.5 MW, 5.8% less than the rated output (12.5% less than the max. output value at the same water head), when both Unit 5# and Unit 6# operate at the same time. Lack of output caused not only the decrease of economic profits of station, but also the increase of the water waste in the flood period.
Inner Scene of the Power Station
In October 2016, Getai Hydropower submitted application and relevant information for the Upgrading and Renovation of Francis Runner of Unit 6# for Huangtankou Hydropower Station, and in April 2017, Getai submitted the application report for commencement of this project. In July that year, Getai received reply for project commencement from Huadian Group, ref. No.: Z.S. (2017) No.79.
New Francis Runner Manufactured By Getai Hydropower
After renovation made by Getai Hydropower, the optimal output of unit is 26.80MW under the testing condition of 30.01m gross head, with the turbine efficiency of 95.07%.
Shaft Seal Assembly
The whole project is implemented in a standard manner, with strict quality control, tracking, inspections and complete data. The final test shows that: the maximum output of the unit is 30.11mw (according to the contract, the turbine unit output shall not be less than 26MW at the rated water head of 28mm and in the upstream water level of at least 115m, and in the downstream water level of at most 86m, and the max. output mat be determined comprehensively based on the technical advantages of Getai Hydropower, when the safe and stable operation of all original components and the whole unit could be guaranteed); the max. efficiency of unit reaches 95.07% (94.5% required by contract); weighted average efficiency is 92.48% (92.02% required by contract); such key indexes as stability and noise, etc., are all better than those required by the contract. Therefore, the renovation of the project has achieved the expected purpose.
Tests By Independent Authority
After this upgrading, the capacity of this Plant has been improved significantly, the max. output of single unit reaching 30MW (only 25.5MW in the original). The units operate well in the most optimized area of rated load.