Indirect Calculation Method Of Water Turbine Flow And Its LabVIEW Application

The Hydroturbine is the core component of the hydroelectric generating unit,and the flow of turbine is an important parameter for the economic operation of the hydropower station.By analyzing the principle and characteristics of the commonly used flow measurement method of hydropower station,and based on the turbine power steady state model,the indirect calculation model of turbine flow is obtained.The turbine flow is calculated indirectly by detecting parameters that are easily and accurately measured by the turbine.Through analysis,it is found that selecting the appropriate hydraulic power steady state model is the key.The commonly used turbine power model in China is six transfer coefficient models,but the unknown parameters that need to be determined are more difficult to use.By comparing the power models of various turbines,it is found that the indirect calculation of the turbine power algebra model recommended by IEEE Working Group is relatively simple and low cost.Therefore,an indirect calculation model of turbine flow is constructed based on the model recommended by IEEE.Since on-site flow measurement is usually performed only under a specific head,there is a large error in applying the measurement results to the analysis of the operating efficiency of the other heads of the unit.Affect the economic operation of the unit.In order to solve this problem,the model has been further improved,and the indirect calculation method of turbine flow is extended to any head,and the efficiency of the unit under different heads is obtained.In order to verify the validity of the traffic model,an example calculation is carried out first.The calculation results show that the proposed method has higher precision.Secondly,the actual application of the method and the accurate measurement method of each parameter are analyzed.Combined with the key laboratory of fluid-solid coupling Kunming University of Science and Technology,the corresponding verification platform was constructed and compared with the flow value measured by ultrasonic method.The relevant data show that the flow rate measured by this method is less than the value measured by ultrasonic method,which further validates the effectiveness of the method.In terms of application,combined with the principle of the volute differential pressure flowmeter and the characteristics of the influence of the head change,the calculation model of the differential pressure coefficient of the volute is obtained.In order to facilitate the actual test application,according to the field test specifications of each parameter of the turbine,the corresponding test system was developed by integrating LabVIEW and NI virtual signal acquisition instrument system,and the flow indirect calculation,turbine efficiency calculation and turbine volute pressure were completed in LabVIEW software.The difference coefficient system displays the development of the interface.The development and integration of the internal algorithm module of the corresponding test system is completed,and the developed test software is installed into the NI virtual instrument system for practical application,and the corresponding parameters can be measured and calculated in real time through the test platform.