Study On Low Frequency Characteristic Of Direct Torque Control About Double Fed Generation

Wind power as a green power has arose people's attention,therefore wind electricity technology gain the quick development too.Moreover wind generator is the main device of wind generator system,it directly affects capability,efficiency and electricity power quality,meantimes affects the operation mode,efficiency and structure.Therefore,it is the core of research and exploiture about wind generator technology.Double fed Generation has become the main machine of wind power generator because of unique technique advantage now.In the control of excitation on double fed generator,the technique of direct torque control become the main method.Whereas DTC exist the problems of low frequency excitation current aberrance and output torque ripple..Aiming at the problem of existent low frequency,the paper put forward the method of improvement on space voltage vector subdivision,which is demonstrate by contrast from simulation study and experiment study.First,the paper detailed discusses the basis structure and operation principle of double fed Generation,some maths model are analysed.Meantimes,the operation characteristic and power balance relation of Double fed Generation are analysed also,which establishes the theory foundation for father rechearch.Second,the paper debates the existent problem of low frequency about DTC.the paper put forward the method of improvement on space voltage vector subdivision.The simulation study is used for the improvement in MATLAB/simulink.The result of research indicates that the method is feasible.In addition,the control systerm of Double Fed Ggenerator about DSP is designed,the main circuits and control circuits is also designed.The systerm can not only work in Generator but also in electromotor.Some control software are compileed and some experiments are done aim at the relative theory.The experiment research indicate that the DTC technology about voltage vector subdivision on DSP controller can improve the dynamic capability of Generator and achieve the expectant control function,which provide the important reference value for the further research of Double fed Generator control technology.