指数法评定水轮机效率的改进方法

Improved method of index test to determine the turbine efficiency

摘要

首先介绍了指数法评定水轮机效率的基本原理，然后分析了原型水轮机的现场流量测量及效率评定中现有研究手段难以得到准确的蜗壳压差流量系数的原因，进而提出了改进的指数法，即利用多个水头下指数法实测结果得出原型水轮机的相对效率，根据相对效率实测值与水轮机制造商预测值的比较，来评定原型水轮机实测效率性能，最终应用于国内一大型水电站的混流式水轮机效率评定中。应用结果表明，改进的指数法得出的水轮机实测效率与预测值较为接近，得到了工程建设各方的认可，是指数法在水轮机效率评定中的一大改进，值得行业借鉴采用，但由于缺少准确的流量数据，该方法不能用于合同保证值的考核及罚款，若各方同意后才可进行实测值与保证值的比较。

Abstract

The basic principle of index test is introduced firstly in this paper, then the difficulties to determine the correct flow differential coefficients on site test to measure and evaluate the discharge and efficiency of prototype turbine by the previous research are concluded. An improved method of index test is proposed to evaluate the prototype turbine efficiency with the measured relative efficiency determined by index test result at different net heads. The turbine efficiency is evaluated by the comparison between the measured result and the predicted values as the relative efficiency. Finally, this improved method is applied to a Francis turbine of a large hydropower station in China. Test result show that the relative efficiency of the improved index method is close to the predicted values from the turbine manufacturer and accepted by the all parties of the project. This improved method is an available solution and helpful reference to proceed index test for prototype turbine. However, due to the lack of accurate discharge, this improved method may be applied to evaluate the guaranteed values and penalties in the contract only when an agreement is made by all parties of the project.

关键词

原型水轮机 / 水轮机效率 / 指数法 / 相对效率 / 加权效率

Key words

prototype turbine / turbine efficiency / index test / relative efficiency / weighted efficiency

Author summay

王 涛(1990—), 男, 高级工程师, 学士, 主要从事水电站水轮发电机组及辅助设备检修维护。E-mail: [e-mail]

基金资助

三峡金沙江云川水电开发有限公司禄劝乌东德电厂科研项目(Z522302058)