| With the aggravation of the energy crisis in the 21st century,the energy industry has heavily favored wind energy,which attracted the whole world’s attention.Our country is promoting structural energy reform and vigorously advocating the R&D and construction of clean energy such as wind power.Wind farms are often located in remote areas with harsh environments,and most wind turbines have been in service for more than five years,with a potential for frequent accidents.The fault diagnosis technology of wind turbines can reduce the failure rate and improve the efficiency of the wind farm.Still,the traditional acquisition method of fault signal has many problems,such as high operation cost,low accuracy and reliability,poor adaptability,and complex equipment transformation.This paper uses a convenient voltage signal to detect wind turbine fault,which has the advantages of nondestructive sampling and fewer measuring points.However,it is not practical to use a real megawatt wind turbine to conduct various fault experiments.Therefore,it is of great significance to build a test platform under laboratory conditions for wind turbines’ fault diagnosis and control research.In this paper,an ideal simulation test platform for wind turbine fault diagnosis is built,which uses voltage signal and retains the core part of the wind turbine.The working principle,hardware structure,and design method of the platform are described.According to the actual fault analysis,different mechanical fault simulation is designed through experiments to simulate and reproduce various wind turbines on site.The shaft misalignment fault,gearbox broken tooth fault,and impeller system fault are designed to simulate single and multiple faults.The purpose of the simulation is to use effective identification methods to identify the corresponding fault characteristics of the collected voltage signal.In this paper,the fast Fourier transform(FFT)and Hilbert-Huang transform(HHT)are used to analyze the changes of fault signals,and the fault types are identified by comparison and theoretical analysis.The experimental results show that this method using the fault frequency in the voltage signal to diagnose has high feasibility and research value.It verifies the feasibility of voltage signal in the case of single fault and multiple faults,the advantages of voltage signal compared with vibration signal,and the research on voltage signal identification method,which provides more data support for the fault diagnosis platform.At the same time,the electric signal collector is equipped with two channels to collect different voltage signals,realizing two different voltage detection requirements of 960v and 24V.It also carries out data acquisition and fault simulation on a 20kW small wind turbine generator.It realizes the process of the electric signal collector from the platform to the minitype aerogenerator.Furthermore,it improves the fault diagnosis technology of electrical signals and lays a foundation for the automatic detection and control of mechanical and electrical faults in the future. |
