Research On FOC Driver Of Auto-guided Wheel Hub Motor

With the deep integration of the new generation of information technology and manufacturing industry,new production methods and industrial forms are emerging.Intelligent factory is leading the change of manufacturing methods.AGV plays an important role in the field of traditional factory transportation,which can greatly reduce labor costs and improve production capacity.As the driving part of AGV,the research of hub motor driver has been widely concerned.By studying the selection of motor and the control method of driver at home and abroad,the design scheme and research content of this paper are determined,and a GaN high frequency drive control system for AGV(automatic guided vehicle)BLDCM is designed.The main contents of this paper are as follows:The reason of the torque ripple of BLDCM is analyzed.The relationship between the switching frequency and the torque ripple of the inverter is inversely derived by mathematics.The performance of Gan device at high frequency is far superior to that of ordinary silicon power device.Therefore,this paper focuses on the design of GaN high frequency driver.According to the structure of BLDCM,the mathematical model is established,and foc(field oriented control)is used as the control algorithm of motor drive.The system adopts modular design scheme,mainly including coordinate transformation module,space vector PWM module and position sensor free control module.The coordinate transformation module decomposes the stator current into two DC components,which are orthogonal and have no influence on each other,so as to control the motor speed accurately.The SVPWM module is mainly for the control of the inverter.The PWM wave generated by the module controls six Ga N switches,so that the three-phase full bridge inverter produces sinusoidal alternating current.The sensorless control module mainly determines the rotor position.Based on the analysis of the traditional sliding mode observer to obtain the rotor position through the arctangent function,this paper proposes an adaptive sliding mode observer based on the phase-locked loop.After estimating the back EMF of the BLDCM,this method can accurately obtain the rotor position information.Based on the design of GaN high frequency driver,the driver circuit module,power module,phase current detection module,over temperature detection module and filter module are designed.Simulink simulation verified that the FOC control system has good control performance.Finally,the driver was tested on the experimental platform based on the main control chip TMS320F28069,which further verified the feasibility of the FOC algorithm for controlling the GaN high-frequency driver of the automatic guided vehicle.