Research On Maximum Power Point Trackink Control Of Six-phase Synchronous Wind Turbine

The excessive consumption of non-renewable energy sources cause serious pollution and destruction of the natural environment,people began to turn their attention to clean and renewable energy.Wind energy is generally considered to be inexhaustible green energy in all of renewable energy.The short development cycle and low environmental requirement make the wind power developing rapidly in the world.With the continuous development of wind power technology,one of the wind power structure with multi-phase generator has become an important research direction.The main research of this paper is the maximum power point tracking control method based on a six-phase synchronous wind power system with distributed converter structure.Firstly,this paper introduces the structure of the six-phase synchronous wind power generation system,including wind turbine,six-phase synchronous generator and two parallel-connected back to back converters.The wind turbine model and related concepts are described,including wind energy utilization factor and tip speed ratio.The winding structure of six-phase synchronous generator is analyzed in detail.At the same time,the mathematic model of six-phase synchronous generator in dq rotating coordinate is established by using space vector decoupling coordinate transformation.For the back to back converters,the main study is the generator-side converter associated with generator control.Secondly,we can get the maximum power point tracking control method in the study of wind turbine maximum wind energy capture.This paper introduces several vector control principle of synchronous motor,then,analyses the maximum power point tracking control method based on optimal torque and vector control method of zero d-axis current in detail.A double closed loop decoupling PI controller is designed for realizing maximum power point tracking of six-phase synchronous wind power generation systems.Finally,the paper introduces the principle of space vector pulse width modulation(SVPWM)for two-level voltage source converter in detail.According to the previous analysis of the wind turbine,six-phase synchronous generator mathematical model and its maximum power point tracking control program,the simulation model of six-phase synchronous wind power generation system is established in Simulink.According to analysis of the simulation results includes wind energy utilization factor,mechanical power,dq-axis current and stator current of six-phase synchronous generation,electric power under different conditions,we can verify the effective of zero d-axis current control and maximum power point tracking control.