Research And Design Of Square Waveform Brushless DC Motor Wind Power Generation Control System

Wind power has been greatly developed by countries because it plays an irreplaceable role in adjusting energy structure and mitigating environmental pollution.Most of the small wind power generation systems are located in relatively remote mountainous areas or offshore areas.The traffic is inconvenient and the system failure rate is getting higher and higher.Therefore,for small wind farms,fault detection and fault-tolerant operation are particularly important.In addition,large-scale wind power generation technology is mature,but small wind turbines cannot directly transplant the control technology of wind turbines directly.Especially for different types of generators,the control methods are different.Therefore,researchers need to develop a set suitable for small wind turbines.Control system.In this thesis,the control of the brushless DC motor wind turbine,the compensation of the position sensorless commutation error and the fault-tolerant control of the rectifier fault are studied.The main work is as follows:Firstly,this thesis introduces the background and research direction of small wind power generation system,and analyzes the research status of brushless DC motor as generator,and establishes the mathematical model and simulation model of wind turbine and brushless DC motor.Based on the analysis of the principle of maximum power tracking control of wind power generation system,this thesis proposes an improved variable step size mountain climbing search method,which makes the system more convenient and fast tracking to the maximum power point.In this thesis,the performance of the brushless DC wind power generation system based on uncontrollable rectification and controllable rectification is analyzed and compared,and the theoretical and simulation basis of the hardware circuit of the project is provided.Secondly,based on the brushless DC motor wind power generation control project,this thesis studies the reason of the commutation error caused by the position sensorless brushless DC motor because of the wind speed change,and proposes the corresponding commutation compensation strategy.In addition,this thesis analyzes the cause of the failure of the rectifier in the brushless DC motor wind power generation system,and proposes a rectifier fault diagnosis method.By analyzing the modulation mode of the brushless DC generator,the fault-tolerant control strategy of the faultless brushless DC motor rectifier is proposed.Finally,this thesis introduces the hardware circuit of the brushless DC wind power generation control system and the operation platform of the wind tunnel test,and analyzes the experimental waveform.The thesis summarizes the work of the full text and looks forward to the follow-up work.