Research On Direct Torque Control Strategy Of Open Winding Brushless Doubly Fed Wind Power Generator

In order to achieve the purpose of sustainable and steady growth of the national economy,the demand for energy is increasing,but excessive use of traditional fossil energy will aggravate environmental pollution.Among the many clean and zero-carbon renewable energy sources,wind energy can follow the development trend of green energy development and utilization.With my country’s "carbon peak,carbon neutral" emission reduction target,the use of wind energy to generate electricity continues to receive attention.The brushless doubly-fed generator can realize variable speed and constant frequency,and has the advantages of small inverter capacity,simple structure,adjustable power factor,low cost,and durability.unit.In this paper,for the open-winding brushless doubly-fed wind turbine,the strategy of direct torque control is selected to achieve power tracking,and the research work is mainly carried out in the following aspects:Firstly,the operating principle of the open-winding brushless doubly-fed wind generator is analyzed,and the energy conversion relationship of the generator in different operating states is discussed.The open-winding brushless doubly-fed wind turbine derives the mathematical model in the d-q rotating coordinate system from the three-phase static coordinate system.Based on this,a simulation model is built in Matlab/Simulink,and the open-winding brushless doubly-fed wind power generation is carried out.The characteristics of the machine in different operating states are simulated and analyzed.Secondly,based on the principle of direct torque control,a direct torque control scheme suitable for open-winding brushless doubly-fed wind turbines is designed.The scheme is based on twelve sectors.The simulation model of the control system is established in the Matlab/Simulink environment,and its operating characteristics are simulated and studied.At the same time,it is compared with the non-open-winding brushless doubly-fed wind turbine.The simulation results show that the brushless doubly-fed wind turbine with open-winding structure The control effect of the wind turbine direct torque control system is better.Finally,comparing the control effects of open-winding brushless doubly-fed generators under different operating conditions,the simulation results show that the torque control effect is affected by the change of the generator speed.