Research On Fault Diagnosis Method Of Three-level Inverter Based On EEMD Sample Entropy

In nowadays society the electronic information technology is developing rapidly,the incidence of automation equipment failure is gradually increasing.In high voltage,high power places,the three level inverter is widely used as one of the important components,but its structure is relatively complex,the reliability is low,so we have to attach importance to the problem.The three level inverter fault handling is still not accurate enough and efficient.In this paper,the EEMD sample entropy algorithm is proposed to study the fault condition of the three-level inverter.In this dissertation,three-level inverter fault diagnosis for the research topic,the object is a diode-clamped three-level inverter.First of all,the dissertation analyzes the three level inverter power device failure of the various situations,from the topological structure and working principle of classifying the power switch tube open circuit fault,fault model is established through the MATLAB platform,the potential voltage waveform of the midpoint of the bridge is obtained under various fault conditions.Secondly,we use the EEMD algorithm to decompose the fault voltage signal into several IMF(Intrinsic Mode Function),select the IMF component to calculate the sample entropy,and get the fault feature vector;Then,the Least Squares Support Vector Machine(LSSVM)algorithm is used to diagnose the fault.The improved Quantum Particle Swarm Optimization(QPSO)algorithm is used to optimize the kernel function and penalty parameters,and the final diagnosis result is obtained.The validity of the algorithm is verified.Finally has carried on the fault diagnosis system based on ARM of overall scheme design.On the hardware,the designed system uses S3C2440 microprocessor chips as the main controller,the peripheral hardware circuit is designed.On the software described in detail to build the various steps of embedded software platform.Confirmed this topic research the feasibility of the algorithm.In this dissertation,the fault diagnosis of three-level inverter is studied.An EEMD sample entropy algorithm is proposed and the final result is obtained.The accuracy of the algorithm is verified by the final result,and tdesign the system.