Research On Inverter Control Strategy Of Wind Power Grid-connected System

At present,the issue of environmental pollution has become a hot topic in the world,which has drawn great attention from countries all over the world.So the new energy also as a hot topic,has become the focus of research.Wind energy is a relatively mature energy source of new energy,and it has become an important goal to expand the application scope of wind power generation to realize the friendly integration of wind farms into the large power grid.Power generation devices generally rely on renewable energy to generate electricity through motor energy conversion.The operation characteristics of the micro grid are that it can still maintain independent operation in the isolated state.Therefore,how to apply micro grid to large power grid and realize smooth and friendly access is a hot research topic in power system nowadays.In this paper,the permanent magnet direct drive fan is used as the power generation device,the output power control is carried out on the side of the inverter to achieve seamless butt joint,and the virtual synchronous generator is introduced.The specific research contents of this paper are as follows:First of all,the introduction part describes the present situation of wind power grid,analyzes the research trend of the use of wind power grid,the grid side of wind motor control strategy is analyzed the research status,fan inverter side control study is divided into two aspects: control research status quo of energy storage device output value and the research status of VSG control applied in the blower interconnection.After that,the structural part of the wind motor is analyzed and introduced.This paper takes the permanent magnet direct drive fan as the power unit,and describes the power generation principle of the fan.The fan structure consists of: permanent magnet direct drive fan,rectifier,energy storage battery device and inverter.The virtual synchronous machine control strategy is applied to the permanent magnet direct drive fan,and the auxiliary function of turning inertia and kinetic energy into electric energy is utilized to set the control mode of the inverter side as a double closed loop control system,and the output value is controlled through the detection of the output quantity,so as to achieve the stability and quality of grid-connected electric energy.The wind motor structure model is built,which lays a foundation for the research of the control system below.Secondly,the control unit simulates the characteristics of traditional thermal power units and establishes the active frequency control link and the reactive voltage control link,which are used to adjust the rotating speed,excitation current and terminal potential,and to optimize the output power quality and the stable continuous output of current.In Matlab/Simulink to build the structure and control part of the simulation system,the virtual synchronous generator technology introduced in the paper is applied to the verification link in the wind power grid-connected system,including the maximum power tracking model of the permanent magnet direct-drive fan,the virtual synchronous generator model and based on The virtual grid-connected wind power generation model controlled by the virtualsynchronous generator simulates the effectiveness of the control scheme proposed in this paper.Under the condition of load and wind speed change,the performance of the model is verified under different operating conditions.Effectively buffering the impact of external environmental changes and improving the output power quality.Under the condition of load fluctuation and wind speed swing,the control method is still effective.The wind power grid-connected system can run normally for normal output and continuous operation.