水电能源科学

针对现有水轮机真机效率试验方法需安装大量测试设备、工程量大、现场适用性受限，难以便捷、精准完成真机效率测试的问题，提出一种基于导叶接力器行程与流量关系辨识的真机效率试验方法。首先通过真机测试与模型换算，建立导叶接力器行程与模型水轮机导叶开度的关系曲线；再结合水轮机模型综合特性曲线计算流量，同步采用水力测试仪器采集水轮机各部位压力与发电机有功功率数据，实现水轮机真机效率试验。同一电站的对比验证表明，该方法测得的水轮机真机流量与超声波测流结果的误差在3%以内。将该方法应用于重庆回龙寨电站机组改造后的效率测试中，发现~#1机组改造后，在20.08 m水头下的水轮机最高效率达93.95%。由此可见，所提试验方法可实现水轮机真机效率的精准测试，兼具可操作性强、成本低的优势，为水电机组能效特性的精准获取与水电站高效运行提供了新的技术路径。

Existing efficiency testing methods for prototype hydro-turbines(PHTs) require the installation of extensive testing equipment, involve heavy engineering workload, and suffer from limited on-site applicability, making it difficult to conveniently and accurately complete prototype efficiency tests. To address these problems, a PHT efficiency testing method based on the identification of the relationship between guide vane servomotor stroke(GVSS) and flow rate is proposed. Firstly, through prototype testing and model conversion, the relationship curve between the GVSS and the guide vane opening(GVO) of the model turbine was established. Then, the flow rate was calculated by combining the model comprehensive characteristic curve(MCCC) of the turbine, while hydraulic testing instruments were simultaneously used to collect the pressure data at various locations of the turbine and the active power data of the generator, thereby realizing the efficiency test of the PHT. Comparative verification at the same hydropower station(HPS) shows that the error between the PHT flow rate measured by this method and the results of ultrasonic flow measurement is within 3%. The proposed method was applied to the efficiency testing of the units at Chongqing Huilongzhai HPS after their retrofit. The results show that after the retrofit of unit ~#1, the maximum efficiency of the turbine reaches 93.95% under a head of 20.08 m. It can be seen that the proposed testing method can achieve accurate efficiency testing of PHTs, with the advantages of strong operability and low cost, providing a new technical pathway for the accurate acquisition of energy efficiency characteristics of hydropower units and the efficient operation of HPSs.