A MATLAB Program for Conversion of Relative Index Test Data into Absolute Flow and Efficiency Data

摘要

This paper describes a computational method developed for conversion of relative index test data into absolute index test data; providing an inexpensive way to obtain absolute efficiency data as well as significantly simplifying the process of traditional index test data reduction. The program iteratively solves for the coefficient values of a new, more accurate form of the Winter- Kennedy piezometer differential calibration equation, by matching the shape of the curve of power to relative flow from index test data to the same curve from a model hill curve stepped up to prototype dimensions. The solution is obtained nearly instantaneously, eliminating tedious hand calculations and reducing the time necessary to produce both turbine-generator relative and absolute efficiency profiles and a CAM curve, or blade angle to wicket gate relation, in order to program the governor for turbine control. Comparing the results of this process with a set of prototype data, for which direct absolute flow measurements were also available, resulted in calculated absolute flow values within 2.5% of both the scintillation and acoustic time of flight measurements. The ability to obtain absolute flow data without expensive measurement techniques will encourage both Type 1 and 2 optimizations of multi-unit hydroelectric power plants for increased power output.