Research On Energy Efficiency Evaluation And Diagnosis Of Wind Turbine

As a kind of large rotating mechanical and electrical equipment, there is strong association coupling between the subsystems of wind turbines. The severe environment of wind farm determines the complexity and variety of the operating conditions. Thus, it is the key and difficult issue to judge the comprehensive running state accuratly in the field of condition monitoring.This paper focus on the wind turbine operation function and takes the function realization degree as the main indexes of running state evaluation.Wind turbine is used to convert the wind energy into electrical energy and has been in a state including multiple forms of energy. In this paper, wind turbine is divided into the wind energy capture system, the mechanical energy transfer system and the electric energy conversion system from the viewpoint of energy flow. Through the research on energy flow mechanism of each system, wind energy utilization coefficient, transmission chain efficiency and generator efficiency are determined as efficiency indexes of the three energy systems, and the related parameters and the influence factors are also extracted.In evaluation section, efficiency distribution of the three systems is determined by engineering experience formula and shafting inverse modeling firstly. Then, the reference ranges of efficiency indexes and related parameters in good operating condition are determined by the method of condition identification and probability statistics. The deviation degree of efficiency indexs and related parameters from the reference ranges are used as the quantitative representation of the energy efficiency rank. And the D-S evidence reasoning model is used to realize the preliminary verification of the three system efficiency indexes and the comprehensive evaluation of the wind turbine.In diagnosis section, the energy efficiency diagnosis tree, library of deterioration reason and optimization measures for the wind turbine are established according to Fault Tree Analysis (FTA).The Principal Component Analysis (PCA) model is used to realize the accurate diagnosis of energy efficiency condition. Then the degradation reasons and optimized adjustment measures are given to provide effective suggestions for the safe and economical operation of wind turbine. The optimization benefit factor and the contribution factor are extracted for the optimization level test of the energy efficiency, and realize the improvement of wind turbine energy efficiency performance.In case anlysis, a Sinovel SL1500 is used to verifiy the feasibility of energy efficiency evaluation and diagnosis research. Finally, a system program of wind turbine energy efficiency is desired based on research ideas in this paper, in order to realize the engineering application of wind turbines energy efficiency research.